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lib/pkp/controllers/grid/users/author/AuthorGridHandler.php

@@ -0,0 +1,476 @@
+<?php
+
+/**
+ * @file controllers/grid/users/author/AuthorGridHandler.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AuthorGridHandler
+ *
+ * @ingroup controllers_grid_users_author
+ *
+ * @deprecated 3.4
+ *
+ * @brief base PKP class to handle author grid requests.
+ */
+
+namespace PKP\controllers\grid\users\author;
+
+use APP\controllers\grid\users\author\form\AuthorForm;
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use PKP\controllers\grid\feature\OrderGridItemsFeature;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\GridHandler;
+use PKP\controllers\grid\settings\user\form\UserDetailsForm;
+use PKP\core\JSONMessage;
+use PKP\core\PKPRequest;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+use PKP\notification\PKPNotification;
+use PKP\security\authorization\PublicationAccessPolicy;
+use PKP\security\Role;
+use PKP\submission\PKPSubmission;
+use PKP\user\User;
+
+class AuthorGridHandler extends GridHandler
+{
+    /** @var bool */
+    public $_readOnly;
+
+    /** @var int */
+    public $_version;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+        $this->addRoleAssignment(
+            [Role::ROLE_ID_MANAGER, Role::ROLE_ID_SUB_EDITOR, Role::ROLE_ID_ASSISTANT, Role::ROLE_ID_AUTHOR],
+            ['fetchGrid', 'fetchRow', 'addAuthor', 'editAuthor',
+                'updateAuthor', 'deleteAuthor', 'saveSequence']
+        );
+        $this->addRoleAssignment(Role::ROLE_ID_REVIEWER, ['fetchGrid', 'fetchRow']);
+        $this->addRoleAssignment([Role::ROLE_ID_MANAGER, Role::ROLE_ID_SUB_EDITOR, Role::ROLE_ID_ASSISTANT], ['addUser']);
+    }
+
+
+    //
+    // Getters/Setters
+    //
+    /**
+     * Get the submission associated with this author grid.
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->getAuthorizedContextObject(Application::ASSOC_TYPE_SUBMISSION);
+    }
+
+    /**
+     * Get the publication associated with this author grid.
+     *
+     * @return Submission
+     */
+    public function getPublication()
+    {
+        return $this->getAuthorizedContextObject(Application::ASSOC_TYPE_PUBLICATION);
+    }
+
+    /**
+     * Get whether or not this grid should be 'read only'
+     *
+     * @return bool
+     */
+    public function getReadOnly()
+    {
+        return $this->_readOnly;
+    }
+
+    /**
+     * Set the boolean for 'read only' status
+     *
+     * @param bool $readOnly
+     */
+    public function setReadOnly($readOnly)
+    {
+        $this->_readOnly = $readOnly;
+    }
+
+    //
+    // Overridden methods from PKPHandler.
+    //
+    /**
+     * @copydoc PKPHandler::authorize()
+     */
+    public function authorize($request, &$args, $roleAssignments)
+    {
+        $this->addPolicy(new PublicationAccessPolicy($request, $args, $roleAssignments));
+        return parent::authorize($request, $args, $roleAssignments);
+    }
+
+    /**
+     * @copydoc GridHandler::initialize()
+     *
+     * @param null|mixed $args
+     */
+    public function initialize($request, $args = null)
+    {
+        parent::initialize($request, $args);
+
+        $this->setTitle('submission.contributors');
+
+        if ($this->getSubmission()->getData('submissionProgress') || $this->canAdminister($request->getUser())) {
+            $this->setReadOnly(false);
+            // Grid actions
+            $router = $request->getRouter();
+            $actionArgs = $this->getRequestArgs();
+
+            $this->addAction(
+                new LinkAction(
+                    'addAuthor',
+                    new AjaxModal(
+                        $router->url($request, null, null, 'addAuthor', null, $actionArgs),
+                        __('grid.action.addContributor'),
+                        'modal_add_user'
+                    ),
+                    __('grid.action.addContributor'),
+                    'add_user'
+                )
+            );
+        } else {
+            $this->setReadOnly(true);
+        }
+
+        // Columns
+        $cellProvider = new PKPAuthorGridCellProvider($this->getPublication());
+        $this->addColumn(
+            new GridColumn(
+                'name',
+                'author.users.contributor.name',
+                null,
+                null,
+                $cellProvider,
+                ['width' => 40, 'alignment' => GridColumn::COLUMN_ALIGNMENT_LEFT]
+            )
+        );
+        $this->addColumn(
+            new GridColumn(
+                'email',
+                'author.users.contributor.email',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+        $this->addColumn(
+            new GridColumn(
+                'role',
+                'author.users.contributor.role',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+        $this->addColumn(
+            new GridColumn(
+                'principalContact',
+                'author.users.contributor.principalContact',
+                null,
+                'controllers/grid/users/author/primaryContact.tpl',
+                $cellProvider
+            )
+        );
+        $this->addColumn(
+            new GridColumn(
+                'includeInBrowse',
+                'author.users.contributor.includeInBrowse',
+                null,
+                'controllers/grid/users/author/includeInBrowse.tpl',
+                $cellProvider
+            )
+        );
+    }
+
+
+    //
+    // Overridden methods from GridHandler
+    //
+    /**
+     * @see GridHandler::initFeatures()
+     */
+    public function initFeatures($request, $args)
+    {
+        $features = parent::initFeatures($request, $args);
+        if ($this->canAdminister($request->getUser())) {
+            $features[] = new OrderGridItemsFeature();
+        }
+        return $features;
+    }
+
+    /**
+     * @copydoc GridHandler::getDataElementSequence()
+     */
+    public function getDataElementSequence($gridDataElement)
+    {
+        return $gridDataElement->getSequence();
+    }
+
+    /**
+     * @copydoc GridHandler::setDataElementSequence()
+     */
+    public function setDataElementSequence($request, $rowId, $gridDataElement, $newSequence)
+    {
+        if (!$this->canAdminister($request->getUser())) {
+            return;
+        }
+
+        $author = Repo::author()->get((int) $rowId, $this->getPublication()->getId());
+
+        Repo::author()->edit($author, ['seq' => $newSequence]);
+    }
+
+    /**
+     * @copydoc GridHandler::getRowInstance()
+     *
+     * @return AuthorGridRow
+     */
+    protected function getRowInstance()
+    {
+        return new AuthorGridRow($this->getSubmission(), $this->getPublication(), $this->getReadOnly());
+    }
+
+    /**
+     * Get the arguments that will identify the data in the grid.
+     * Overridden by child grids.
+     *
+     * @return array
+     */
+    public function getRequestArgs()
+    {
+        $submission = $this->getSubmission();
+        $publication = $this->getPublication();
+        return [
+            'submissionId' => $submission->getId(),
+            'publicationId' => $publication->getId()
+        ];
+    }
+
+    /**
+     * Determines if there should be add/edit actions on this grid.
+     *
+     * @param User $user
+     *
+     * @return bool
+     */
+    public function canAdminister($user)
+    {
+        $publication = $this->getPublication();
+        $submission = $this->getSubmission();
+        $userRoles = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_USER_ROLES);
+
+        if ($publication->getData('status') === PKPSubmission::STATUS_PUBLISHED) {
+            return false;
+        }
+
+        if (in_array(Role::ROLE_ID_SITE_ADMIN, $userRoles)) {
+            return true;
+        }
+
+        // Incomplete submissions can be edited. (Presumably author.)
+        if ($submission->getDateSubmitted() == null) {
+            return true;
+        }
+
+        // The user may not be allowed to edit the metadata
+        if (Repo::submission()->canEditPublication($submission->getId(), $user->getId())) {
+            return true;
+        }
+
+        // Default: Read-only.
+        return false;
+    }
+
+    /**
+     * @copydoc GridHandler::loadData()
+     *
+     * @param null|mixed $filter
+     */
+    protected function loadData($request, $filter = null)
+    {
+        return Repo::author()
+            ->getCollector()
+            ->filterByPublicationIds([$this->getPublication()->getId()])
+            ->orderBy(Repo::author()->getCollector()::ORDERBY_SEQUENCE)
+            ->getMany();
+    }
+
+    //
+    // Public Author Grid Actions
+    //
+    /**
+     * An action to manually add a new author
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     */
+    public function addAuthor($args, $request)
+    {
+        if (!$this->canAdminister($request->getUser())) {
+            return new JSONMessage(false);
+        }
+        // Calling editAuthor() with an empty row id will add
+        // a new author.
+        return $this->editAuthor($args, $request);
+    }
+
+    /**
+     * Edit an author
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function editAuthor($args, $request)
+    {
+        if (!$this->canAdminister($request->getUser())) {
+            return new JSONMessage(false);
+        }
+        // Identify the author to be updated
+        $authorId = (int) $request->getUserVar('authorId');
+
+        $author = Repo::author()->get($authorId, $this->getPublication()->getId());
+
+        // Form handling
+        $authorForm = new AuthorForm($this->getPublication(), $author);
+        $authorForm->initData();
+
+        return new JSONMessage(true, $authorForm->fetch($request));
+    }
+
+    /**
+     * Update an author
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function updateAuthor($args, $request)
+    {
+        if (!$this->canAdminister($request->getUser())) {
+            return new JSONMessage(false);
+        }
+        // Identify the author to be updated
+        $authorId = (int) $request->getUserVar('authorId');
+        $publication = $this->getPublication();
+
+        $author = Repo::author()->get($authorId, $publication->getId());
+
+        // Form handling
+        $authorForm = new AuthorForm($publication, $author);
+        $authorForm->readInputData();
+        if ($authorForm->validate()) {
+            $authorId = $authorForm->execute();
+
+            if (!isset($author)) {
+                // This is a new contributor
+                $author = Repo::author()->get($authorId, $publication->getId());
+                // New added author action notification content.
+                $notificationContent = __('notification.addedAuthor');
+            } else {
+                // Author edition action notification content.
+                $notificationContent = __('notification.editedAuthor');
+            }
+
+            // Create trivial notification.
+            $currentUser = $request->getUser();
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification($currentUser->getId(), PKPNotification::NOTIFICATION_TYPE_SUCCESS, ['contents' => $notificationContent]);
+
+            // Prepare the grid row data
+            $row = $this->getRowInstance();
+            $row->setGridId($this->getId());
+            $row->setId($authorId);
+            $row->setData($author);
+            $row->initialize($request);
+
+            // Render the row into a JSON response
+            if ($author->getPrimaryContact()) {
+                // If this is the primary contact, redraw the whole grid
+                // so that it takes the checkbox off other rows.
+                $json = \PKP\db\DAO::getDataChangedEvent();
+            } else {
+                $json = \PKP\db\DAO::getDataChangedEvent($authorId);
+            }
+            $json->setGlobalEvent('authorsUpdated');
+            return $json;
+        } else {
+            return new JSONMessage(true, $authorForm->fetch($request));
+        }
+    }
+
+    /**
+     * Delete a author
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function deleteAuthor($args, $request)
+    {
+        if (!$request->checkCSRF()) {
+            return new JSONMessage(false);
+        }
+        if (!$this->canAdminister($request->getUser())) {
+            return new JSONMessage(false);
+        }
+
+        $authorId = (int) $request->getUserVar('authorId');
+        $author = Repo::author()->get($authorId, $this->getPublication()->getId());
+        if (!$author) {
+            return new JSONMessage(false);
+        }
+
+        Repo::author()->delete($author);
+
+        $json = \PKP\db\DAO::getDataChangedEvent($authorId);
+        $json->setGlobalEvent('authorsUpdated');
+        return $json;
+    }
+
+    /**
+     * Add a user with data initialized from an existing author.
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function addUser($args, $request)
+    {
+        // Identify the author Id.
+        $authorId = (int) $request->getUserVar('authorId');
+
+        $author = Repo::author()->get($authorId, $this->getPublication()->getId());
+
+        if ($author !== null && Repo::user()->getByEmail($author->getEmail(), true)) {
+            // We don't have administrative rights over this user.
+            return new JSONMessage(false, __('grid.user.cannotAdminister'));
+        }
+
+        // Form handling.
+        $userForm = new UserDetailsForm($request, null, $author);
+        $userForm->attachValidationChecks($request)->initData();
+
+        return new JSONMessage(true, $userForm->display($request));
+    }
+}

lib/pkp/controllers/grid/users/author/AuthorGridRow.php

@@ -0,0 +1,185 @@
+<?php
+
+/**
+ * @file controllers/grid/users/author/AuthorGridRow.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AuthorGridRow
+ *
+ * @ingroup controllers_grid_users_author
+ *
+ * @deprecated 3.4
+ *
+ * @brief Base class for author grid row definition
+ */
+
+namespace PKP\controllers\grid\users\author;
+
+use APP\facades\Repo;
+use APP\publication\Publication;
+use APP\submission\Submission;
+use PKP\controllers\grid\GridRow;
+use PKP\core\PKPRequest;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+use PKP\linkAction\request\RemoteActionConfirmationModal;
+
+class AuthorGridRow extends GridRow
+{
+    /** @var Submission */
+    public $_submission;
+
+    /** @var Publication */
+    public $_publication;
+
+    /** @var bool */
+    public $_readOnly;
+
+    /** @var int */
+    public $_version;
+
+    /**
+     * Constructor
+     */
+    public function __construct($submission, $publication, $readOnly = false)
+    {
+        $this->_submission = $submission;
+        $this->_publication = $publication;
+        $this->_readOnly = $readOnly;
+        parent::__construct();
+    }
+
+    //
+    // Overridden methods from GridRow
+    //
+    /**
+     * @copydoc GridRow::initialize()
+     *
+     * @param null|mixed $template
+     */
+    public function initialize($request, $template = null)
+    {
+        // Do the default initialization
+        parent::initialize($request, $template);
+
+        // Is this a new row or an existing row?
+        $rowId = $this->getId();
+        if (!empty($rowId) && is_numeric($rowId)) {
+            // Only add row actions if this is an existing row
+            $router = $request->getRouter();
+            $actionArgs = $this->getRequestArgs();
+            $actionArgs['authorId'] = $rowId;
+
+            if (!$this->isReadOnly()) {
+                // Add row-level actions
+                $this->addAction(
+                    new LinkAction(
+                        'editAuthor',
+                        new AjaxModal(
+                            $router->url($request, null, null, 'editAuthor', null, $actionArgs),
+                            __('grid.action.editContributor'),
+                            'modal_edit'
+                        ),
+                        __('grid.action.edit'),
+                        'edit'
+                    )
+                );
+
+                $this->addAction(
+                    new LinkAction(
+                        'deleteAuthor',
+                        new RemoteActionConfirmationModal(
+                            $request->getSession(),
+                            __('common.confirmDelete'),
+                            __('common.delete'),
+                            $router->url($request, null, null, 'deleteAuthor', null, $actionArgs),
+                            'modal_delete'
+                        ),
+                        __('grid.action.delete'),
+                        'delete'
+                    )
+                );
+
+                $author = Repo::author()->get((int) $rowId, $this->getPublication()->getId());
+
+                if ($author && !Repo::user()->getByEmail($author->getEmail(), true)) {
+                    $this->addAction(
+                        new LinkAction(
+                            'addUser',
+                            new AjaxModal(
+                                $router->url($request, null, null, 'addUser', null, $actionArgs),
+                                __('grid.user.add'),
+                                'modal_add_user',
+                                true
+                            ),
+                            __('grid.user.add'),
+                            'add_user'
+                        )
+                    );
+                }
+            }
+        }
+    }
+
+    /**
+     * Get the submission for this row (already authorized)
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->_submission;
+    }
+
+    /**
+     * Get the publication for this row (already authorized)
+     *
+     * @return Publication
+     */
+    public function getPublication()
+    {
+        return $this->_publication;
+    }
+
+    /**
+     * Get the base arguments that will identify the data in the grid.
+     *
+     * @return array
+     */
+    public function getRequestArgs()
+    {
+        $submission = $this->getSubmission();
+        $publication = $this->getPublication();
+        return [
+            'submissionId' => $submission->getId(),
+            'publicationId' => $publication->getId()
+        ];
+    }
+
+    /**
+     * Determines whether the current user can create user accounts from authors present
+     * in the grid.
+     * Overridden by child grid rows.
+     *
+     * @param PKPRequest $request
+     *
+     * @return bool
+     */
+    public function allowedToCreateUser($request)
+    {
+        return false;
+    }
+
+    /**
+     * Determine if this grid row should be read only.
+     *
+     * @return bool
+     */
+    public function isReadOnly()
+    {
+        return $this->_readOnly;
+    }
+}

lib/pkp/controllers/grid/users/author/PKPAuthorGridCellProvider.php

@@ -0,0 +1,72 @@
+<?php
+
+/**
+ * @file controllers/grid/users/author/PKPAuthorGridCellProvider.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class PKPAuthorGridCellProvider
+ *
+ * @ingroup controllers_grid_users_author
+ *
+ * @deprecated 3.4
+ *
+ * @brief Base class for a cell provider that can retrieve labels for submission contributors
+ */
+
+namespace PKP\controllers\grid\users\author;
+
+use APP\author\Author;
+use APP\publication\Publication;
+use PKP\controllers\grid\DataObjectGridCellProvider;
+use PKP\controllers\grid\GridColumn;
+
+class PKPAuthorGridCellProvider extends DataObjectGridCellProvider
+{
+    /** @var Publication The publication this author is related to */
+    private $_publication;
+
+    /**
+     * Constructor
+     *
+     * @param Publication $publication
+     */
+    public function __construct($publication)
+    {
+        $this->_publication = $publication;
+    }
+
+    //
+    // Template methods from GridCellProvider
+    //
+    /**
+     * Extracts variables for a given column from a data element
+     * so that they may be assigned to template before rendering.
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return array
+     */
+    public function getTemplateVarsFromRowColumn($row, $column)
+    {
+        $element = $row->getData();
+        $columnId = $column->getId();
+        assert($element instanceof \PKP\core\DataObject && !empty($columnId));
+        /** @var Author $element */
+        switch ($columnId) {
+            case 'name':
+                return ['label' => $element->getFullName()];
+            case 'role':
+                return ['label' => $element->getLocalizedUserGroupName()];
+            case 'email':
+                return parent::getTemplateVarsFromRowColumn($row, $column);
+            case 'principalContact':
+                return ['isPrincipalContact' => $this->_publication->getData('primaryContactId') === $element->getId()];
+            case 'includeInBrowse':
+                return ['includeInBrowse' => $element->getIncludeInBrowse()];
+        }
+    }
+}

lib/pkp/controllers/grid/users/author/form/PKPAuthorForm.php

@@ -0,0 +1,271 @@
+<?php
+
+/**
+ * @file controllers/grid/users/author/form/PKPAuthorForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class PKPAuthorForm
+ *
+ * @ingroup controllers_grid_users_author_form
+ *
+ * @deprecated 3.4
+ *
+ * @brief Form for adding/editing a author
+ */
+
+namespace PKP\controllers\grid\users\author\form;
+
+use APP\author\Author;
+use APP\core\Services;
+use APP\facades\Repo;
+use APP\publication\Publication;
+use APP\template\TemplateManager;
+use Exception;
+use PKP\facades\Locale;
+use PKP\form\Form;
+use PKP\security\Role;
+
+class PKPAuthorForm extends Form
+{
+    /** @var Publication publication associated with the contributor being edited */
+    public $_publication;
+
+    /** @var Author the author being edited */
+    public $_author;
+
+    /**
+     * Constructor.
+     *
+     * @param Publication $publication
+     */
+    public function __construct($publication, $author)
+    {
+        parent::__construct('controllers/grid/users/author/form/authorForm.tpl');
+        $this->setPublication($publication);
+        $this->setAuthor($author);
+
+        // the publication locale should be the default/required locale
+        $this->setDefaultFormLocale($publication->getData('locale'));
+
+        // Validation checks for this form
+        $form = $this;
+        $this->addCheck(new \PKP\form\validation\FormValidatorLocale($this, 'givenName', 'required', 'user.profile.form.givenNameRequired', $this->defaultLocale));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCustom($this, 'familyName', 'optional', 'user.profile.form.givenNameRequired.locale', function ($familyName) use ($form) {
+            $givenNames = $form->getData('givenName');
+            foreach ($familyName as $locale => $value) {
+                if (!empty($value) && empty($givenNames[$locale])) {
+                    return false;
+                }
+            }
+            return true;
+        }));
+        $this->addCheck(new \PKP\form\validation\FormValidatorEmail($this, 'email', 'required', 'form.emailRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorUrl($this, 'userUrl', 'optional', 'user.profile.form.urlInvalid'));
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'userGroupId', 'required', 'submission.submit.form.contributorRoleRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorORCID($this, 'orcid', 'optional', 'user.orcid.orcidInvalid'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    //
+    // Getters and Setters
+    //
+    /**
+     * Get the author
+     *
+     * @return Author
+     */
+    public function getAuthor(): ?Author
+    {
+        return $this->_author;
+    }
+
+    /**
+     * Set the author
+     *
+     * @param Author $author
+     */
+    public function setAuthor($author)
+    {
+        $this->_author = $author;
+    }
+
+    /**
+     * Get the Publication
+     *
+     * @return Publication
+     */
+    public function getPublication()
+    {
+        return $this->_publication;
+    }
+
+    /**
+     * Set the Publication
+     *
+     * @param Publication $publication
+     */
+    public function setPublication($publication)
+    {
+        $this->_publication = $publication;
+    }
+
+
+    //
+    // Overridden template methods
+    //
+    /**
+     * Initialize form data from the associated author.
+     */
+    public function initData()
+    {
+        $author = $this->getAuthor();
+
+        if ($author) {
+            $this->_data = [
+                'authorId' => $author->getId(),
+                'givenName' => $author->getGivenName(null),
+                'familyName' => $author->getFamilyName(null),
+                'preferredPublicName' => $author->getPreferredPublicName(null),
+                'affiliation' => $author->getAffiliation(null),
+                'country' => $author->getCountry(),
+                'email' => $author->getEmail(),
+                'userUrl' => $author->getUrl(),
+                'orcid' => $author->getOrcid(),
+                'competingInterests' => $author->getCompetingInterests(null),
+                'userGroupId' => $author->getUserGroupId(),
+                'biography' => $author->getBiography(null),
+                'primaryContact' => $this->getPublication()->getData('primaryContactId') === $author->getId(),
+                'includeInBrowse' => $author->getIncludeInBrowse(),
+            ];
+        } else {
+            // assume authors should be listed unless otherwise specified.
+            $this->_data = ['includeInBrowse' => true];
+        }
+        // in order to be able to use the hook
+        return parent::initData();
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $context = $request->getContext();
+        $authorUserGroups = Repo::userGroup()->getByRoleIds([Role::ROLE_ID_AUTHOR], $context->getId());
+        $publication = $this->getPublication();
+        $countries = [];
+        foreach (Locale::getCountries() as $country) {
+            $countries[$country->getAlpha2()] = $country->getLocalName();
+        }
+        asort($countries);
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign([
+            'submissionId' => $publication->getData('submissionId'),
+            'publicationId' => $publication->getId(),
+            'countries' => $countries,
+            'authorUserGroups' => $authorUserGroups,
+            'requireAuthorCompetingInterests' => $context->getData('requireAuthorCompetingInterests'),
+        ]);
+
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'authorId',
+            'givenName',
+            'familyName',
+            'preferredPublicName',
+            'affiliation',
+            'country',
+            'email',
+            'userUrl',
+            'orcid',
+            'competingInterests',
+            'userGroupId',
+            'biography',
+            'primaryContact',
+            'includeInBrowse',
+        ]);
+    }
+
+    /**
+     * Save author
+     *
+     * @see Form::execute()
+     */
+    public function execute(...$functionParams)
+    {
+        $publication = $this->getPublication(); /** @var Publication $publication */
+        $submission = Repo::submission()->get($publication->getData('submissionId'));
+        $context = Services::get('context')->get($submission->getData('contextId'));
+
+        $author = $this->getAuthor();
+        if (!$author) {
+            // this is a new submission contributor
+            $this->_author = Repo::author()->newDataObject();
+            $author = $this->getAuthor();
+            $author->setData('publicationId', $publication->getId());
+            $author->setData('seq', count($publication->getData('authors')));
+            $existingAuthor = false;
+        } else {
+            $existingAuthor = true;
+            if ($publication->getId() !== $author->getData('publicationId')) {
+                fatalError('Invalid author!');
+            }
+        }
+
+        $author->setGivenName(array_map('trim', $this->getData('givenName')), null);
+        $author->setFamilyName($this->getData('familyName'), null);
+        $author->setPreferredPublicName($this->getData('preferredPublicName'), null);
+        $author->setAffiliation($this->getData('affiliation'), null); // localized
+        $author->setCountry($this->getData('country'));
+        $author->setEmail($this->getData('email'));
+        $author->setUrl($this->getData('userUrl'));
+        $author->setOrcid($this->getData('orcid'));
+        if ($context->getData('requireAuthorCompetingInterests')) {
+            $author->setCompetingInterests($this->getData('competingInterests'), null);
+        }
+        $author->setUserGroupId($this->getData('userGroupId'));
+        $author->setBiography($this->getData('biography'), null); // localized
+        $author->setIncludeInBrowse(($this->getData('includeInBrowse') ? true : false));
+
+        // in order to be able to use the hook
+        parent::execute(...$functionParams);
+
+        if ($existingAuthor) {
+            Repo::author()->edit($author, []);
+            $authorId = $author->getId();
+        } else {
+            $authorId = Repo::author()->add($author);
+        }
+
+        if ($this->getData('primaryContact')) {
+            $params = ['primaryContactId' => $authorId];
+            $errors = Repo::publication()->validate(
+                $publication,
+                $params,
+                $submission,
+                $context
+            );
+            if (!empty($errors)) {
+                throw new Exception('Invalid primary contact ID. This author can not be a primary contact.');
+            }
+            Repo::publication()->edit($publication, $params);
+        }
+
+        return $authorId;
+    }
+}

lib/pkp/controllers/grid/users/exportableUsers/ExportableUsersGridHandler.php

@@ -0,0 +1,289 @@
+<?php
+
+/**
+ * @file controllers/grid/users/exportableUsers/ExportableUsersGridHandler.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ExportableUsersGridHandler
+ *
+ * @ingroup controllers_grid_users_exportableUsers
+ *
+ * @brief Handle exportable user grid requests.
+ */
+
+namespace PKP\controllers\grid\users\exportableUsers;
+
+use APP\facades\Repo;
+use PKP\controllers\grid\DataObjectGridCellProvider;
+use PKP\controllers\grid\feature\PagingFeature;
+use PKP\controllers\grid\feature\selectableItems\SelectableItemsFeature;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\GridHandler;
+use PKP\core\PKPApplication;
+use PKP\identity\Identity;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\RedirectConfirmationModal;
+use PKP\security\authorization\ContextAccessPolicy;
+use PKP\security\Role;
+
+class ExportableUsersGridHandler extends GridHandler
+{
+    public $_pluginName;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+        $this->addRoleAssignment(
+            [Role::ROLE_ID_MANAGER, Role::ROLE_ID_SITE_ADMIN],
+            ['fetchGrid', 'fetchRow']
+        );
+    }
+
+
+    //
+    // Implement template methods from PKPHandler.
+    //
+    /**
+     * @copydoc PKPHandler::authorize()
+     */
+    public function authorize($request, &$args, $roleAssignments)
+    {
+        $this->addPolicy(new ContextAccessPolicy($request, $roleAssignments));
+        return parent::authorize($request, $args, $roleAssignments);
+    }
+
+    /**
+     * @copydoc GridHandler::initialize()
+     *
+     * @param null|mixed $args
+     */
+    public function initialize($request, $args = null)
+    {
+        parent::initialize($request, $args);
+
+        // Basic grid configuration.
+        $this->setTitle('grid.user.currentUsers');
+
+        // Grid actions.
+        $router = $request->getRouter();
+        $pluginName = $request->getUserVar('pluginName');
+        assert(!empty($pluginName));
+        $this->_pluginName = $pluginName;
+
+        $dispatcher = $request->getDispatcher();
+        $url = $dispatcher->url($request, PKPApplication::ROUTE_PAGE, null, 'management', 'importexport', ['plugin', $pluginName, 'exportAllUsers']);
+
+        $this->addAction(
+            new LinkAction(
+                'exportAllUsers',
+                new RedirectConfirmationModal(
+                    __('grid.users.confirmExportAllUsers'),
+                    null,
+                    $url
+                ),
+                __('grid.action.exportAllUsers'),
+                'export_users'
+            )
+        );
+
+        //
+        // Grid columns.
+        //
+
+        // First Name.
+        $cellProvider = new DataObjectGridCellProvider();
+        $this->addColumn(
+            new GridColumn(
+                'givenName',
+                'user.givenName',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+
+        // Last Name.
+        $cellProvider = new DataObjectGridCellProvider();
+        $this->addColumn(
+            new GridColumn(
+                'familyName',
+                'user.familyName',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+
+        // User name.
+        $cellProvider = new DataObjectGridCellProvider();
+        $this->addColumn(
+            new GridColumn(
+                'username',
+                'user.username',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+
+        // Email.
+        $cellProvider = new DataObjectGridCellProvider();
+        $this->addColumn(
+            new GridColumn(
+                'email',
+                'user.email',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+    }
+
+
+    //
+    // Implement methods from GridHandler.
+    //
+    /**
+     * @copydoc GridHandler::initFeatures()
+     */
+    public function initFeatures($request, $args)
+    {
+        return [new SelectableItemsFeature(), new PagingFeature()];
+    }
+
+    /**
+     * @copydoc GridHandler::getSelectName()
+     */
+    public function getSelectName()
+    {
+        return 'selectedUsers';
+    }
+
+    //
+    // Implemented methods from GridHandler.
+    //
+    /**
+     * @copydoc GridHandler::isDataElementSelected()
+     */
+    public function isDataElementSelected($gridDataElement)
+    {
+        return false; // Nothing is selected by default
+    }
+
+    /**
+     * @copydoc GridHandler::loadData()
+     */
+    protected function loadData($request, $filter)
+    {
+        // Get the context.
+        $context = $request->getContext();
+
+        // The user interface uses filter['userGroup'] and $filter['search']
+        $userGroupSearchTerm = $filter['userGroup'] ? [$filter['userGroup']] : null;
+
+        $userCollector = Repo::user()->getCollector()
+            ->filterByContextIds([$context->getId()])
+            ->searchPhrase($filter['search'])
+            ->filterByUserGroupIds($userGroupSearchTerm);
+
+        // Get all users for this context that match search criteria.
+        $rangeInfo = $this->getGridRangeInfo($request, $this->getId());
+        $totalCount = $userCollector->getCount();
+        $userCollector->limit($rangeInfo->getCount());
+        $userCollector->offset($rangeInfo->getOffset() + max(0, $rangeInfo->getPage() - 1) * $rangeInfo->getCount());
+        $iterator = $userCollector->getMany();
+        return new \PKP\core\VirtualArrayIterator(iterator_to_array($iterator, true), $totalCount, $rangeInfo->getPage(), $rangeInfo->getCount());
+    }
+
+    /**
+     * @copydoc GridHandler::renderFilter()
+     */
+    public function renderFilter($request, $filterData = [])
+    {
+        $context = $request->getContext();
+
+        $userGroups = Repo::userGroup()->getCollector()
+            ->filterByContextIds([$context->getId()])
+            ->getMany();
+
+        $userGroupOptions = ['' => __('grid.user.allRoles')];
+        foreach ($userGroups as $userGroup) {
+            $userGroupOptions[$userGroup->getId()] = $userGroup->getLocalizedName();
+        }
+        $userDao = Repo::user()->dao;
+        $fieldOptions = [
+            Identity::IDENTITY_SETTING_GIVENNAME => 'user.givenName',
+            Identity::IDENTITY_SETTING_FAMILYNAME => 'user.familyName',
+            $userDao::USER_FIELD_USERNAME => 'user.username',
+            $userDao::USER_FIELD_EMAIL => 'user.email'
+        ];
+
+        $matchOptions = [
+            'contains' => 'form.contains',
+            'is' => 'form.is'
+        ];
+
+        $filterData = [
+            'userGroupOptions' => $userGroupOptions,
+            'fieldOptions' => $fieldOptions,
+            'matchOptions' => $matchOptions
+        ];
+
+        return parent::renderFilter($request, $filterData);
+    }
+
+    /**
+     * @copydoc GridHandler::getFilterSelectionData()
+     *
+     * @return array Filter selection data.
+     */
+    public function getFilterSelectionData($request)
+    {
+        // Get the search terms.
+        $userGroup = $request->getUserVar('userGroup') ? (int)$request->getUserVar('userGroup') : null;
+        $searchField = $request->getUserVar('searchField');
+        $searchMatch = $request->getUserVar('searchMatch');
+        $search = $request->getUserVar('search');
+
+        return $filterSelectionData = [
+            'userGroup' => $userGroup,
+            'searchField' => $searchField,
+            'searchMatch' => $searchMatch,
+            'search' => $search ? $search : ''
+        ];
+    }
+
+    /**
+     * @copydoc GridHandler::getFilterForm()
+     *
+     * @return string Filter template.
+     */
+    protected function getFilterForm()
+    {
+        return 'controllers/grid/users/exportableUsers/userGridFilter.tpl';
+    }
+
+    /**
+     * @see GridHandler::getRequestArgs()
+     */
+    public function getRequestArgs()
+    {
+        return array_merge(parent::getRequestArgs(), ['pluginName' => $this->_getPluginName()]);
+    }
+
+    /**
+     * Fetch the name of the plugin for this grid's calling context.
+     *
+     * @return string
+     */
+    public function _getPluginName()
+    {
+        return $this->_pluginName;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/AuthorReviewerGridCellProvider.php

@@ -0,0 +1,181 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/AuthorReviewerGridCellProvider.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AuthorReviewerGridCellProvider
+ *
+ * @ingroup controllers_grid_users_reviewer
+ *
+ * @brief Base class for a cell provider that can retrieve labels for reviewer grid rows in author workflow
+ */
+
+namespace PKP\controllers\grid\users\reviewer;
+
+use APP\facades\Repo;
+use PKP\controllers\grid\DataObjectGridCellProvider;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\GridHandler;
+use PKP\controllers\review\linkAction\ReviewNotesLinkAction;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+
+class AuthorReviewerGridCellProvider extends DataObjectGridCellProvider
+{
+    //
+    // Template methods from GridCellProvider
+    //
+    /**
+     * Gathers the state of a given cell given a $row/$column combination
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return string
+     */
+    public function getCellState($row, $column)
+    {
+        $reviewAssignment = $row->getData();
+        $columnId = $column->getId();
+        assert($reviewAssignment instanceof \PKP\core\DataObject && !empty($columnId));
+        /** @var ReviewAssignment $reviewAssignment */
+        switch ($columnId) {
+            case 'name':
+            case 'method':
+                return '';
+            case 'considered':
+            case 'actions':
+                return $reviewAssignment->getStatus();
+        }
+    }
+
+    /**
+     * Extracts variables for a given column from a data element
+     * so that they may be assigned to template before rendering.
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return array
+     */
+    public function getTemplateVarsFromRowColumn($row, $column)
+    {
+        $element = $row->getData();
+        $columnId = $column->getId();
+        assert($element instanceof \PKP\core\DataObject && !empty($columnId));
+        /** @var ReviewAssignment $element */
+        switch ($columnId) {
+            case 'name':
+                return ['label' => $element->getReviewerFullName()];
+
+            case 'method':
+                return ['label' => __($element->getReviewMethodKey())];
+
+            case 'considered':
+                $statusText = $this->_getStatusText($this->getCellState($row, $column), $row);
+                $reviewAssignment = $row->getData();
+                $competingInterests = $reviewAssignment->getCompetingInterests();
+                if ($competingInterests) {
+                    $statusText .= '<span class="details">' . __('reviewer.competingInterests') . '</span>';
+                }
+                return ['label' => $statusText];
+
+            case 'actions':
+                // Only attach actions to this column. See self::getCellActions()
+                return ['label' => ''];
+        }
+
+        return parent::getTemplateVarsFromRowColumn($row, $column);
+    }
+
+    /**
+     * Get cell actions associated with this row/column combination
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return ?array an array of LinkAction instances
+     */
+    public function getCellActions($request, $row, $column, $position = GridHandler::GRID_ACTION_POSITION_DEFAULT)
+    {
+        $reviewAssignment = $row->getData();
+        $actionArgs = [
+            'submissionId' => $reviewAssignment->getSubmissionId(),
+            'reviewAssignmentId' => $reviewAssignment->getId(),
+            'stageId' => $reviewAssignment->getStageId(),
+        ];
+
+        $submission = Repo::submission()->get($reviewAssignment->getSubmissionId());
+
+        // Only attach actions to the actions column. The actions and status
+        // columns share state values.
+        $columnId = $column->getId();
+        if ($columnId == 'actions') {
+            switch ($this->getCellState($row, $column)) {
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_COMPLETE:
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_THANKED:
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RECEIVED:
+                    $user = $request->getUser();
+                    return [new ReviewNotesLinkAction($request, $reviewAssignment, $submission, $user, 'grid.users.reviewer.AuthorReviewerGridHandler', true)];
+                default:
+                    return null;
+            }
+        }
+        return parent::getCellActions($request, $row, $column, $position);
+    }
+
+    /**
+     * Provide meaningful locale keys for the various grid status states.
+     *
+     * @param string $state
+     * @param \PKP\controllers\grid\GridRow $row
+     *
+     * @return string
+     */
+    public function _getStatusText($state, $row)
+    {
+        $reviewAssignment = $row->getData();
+        switch ($state) {
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_AWAITING_RESPONSE:
+                return '<span class="state">' . __('editor.review.requestSent') . '</span><span class="details">' . __('editor.review.responseDue', ['date' => substr($reviewAssignment->getDateResponseDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_ACCEPTED:
+                return '<span class="state">' . __('editor.review.requestAccepted') . '</span><span class="details">' . __('editor.review.reviewDue', ['date' => substr($reviewAssignment->getDateDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_COMPLETE:
+                return $this->_getStatusWithRecommendation('common.complete', $reviewAssignment);
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_REVIEW_OVERDUE:
+                return '<span class="state overdue">' . __('common.overdue') . '</span><span class="details">' . __('editor.review.reviewDue', ['date' => substr($reviewAssignment->getDateDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RESPONSE_OVERDUE:
+                return '<span class="state overdue">' . __('common.overdue') . '</span><span class="details">' . __('editor.review.responseDue', ['date' => substr($reviewAssignment->getDateResponseDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_DECLINED:
+                return '<span class="state declined">' . __('common.declined') . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_CANCELLED:
+                return '<span class="state cancelled">' . __('common.cancelled') . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RECEIVED:
+                return  $this->_getStatusWithRecommendation('editor.review.reviewSubmitted', $reviewAssignment);
+            default:
+                return '';
+        }
+    }
+
+    /**
+     * Retrieve a formatted HTML string that displays the state of the review
+     * with the review recommendation if one exists. Or return just the state.
+     * Only works with some states.
+     *
+     * @param string $statusKey Locale key for status text
+     * @param \PKP\submission\reviewAssignment\ReviewAssignment $reviewAssignment
+     *
+     * @return string
+     */
+    public function _getStatusWithRecommendation($statusKey, $reviewAssignment)
+    {
+        if (!$reviewAssignment->getRecommendation()) {
+            return __($statusKey);
+        }
+
+        return '<span class="state">' . __($statusKey) . '</span><span class="details">' . __('submission.recommendation', ['recommendation' => $reviewAssignment->getLocalizedRecommendation()]) . '</span>';
+    }
+}

lib/pkp/controllers/grid/users/reviewer/AuthorReviewerGridHandler.php

@@ -0,0 +1,213 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/AuthorReviewerGridHandler.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AuthorReviewerGridHandler
+ *
+ * @ingroup controllers_grid_users_reviewer
+ *
+ * @brief Handle reviewer grid requests from author workflow in open reviews
+ */
+
+namespace PKP\controllers\grid\users\reviewer;
+
+use APP\core\Application;
+use APP\template\TemplateManager;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\GridHandler;
+use PKP\core\JSONMessage;
+use PKP\core\PKPRequest;
+use PKP\db\DAORegistry;
+use PKP\reviewForm\ReviewFormDAO;
+use PKP\reviewForm\ReviewFormElementDAO;
+use PKP\reviewForm\ReviewFormResponseDAO;
+use PKP\security\authorization\internal\ReviewAssignmentRequiredPolicy;
+use PKP\security\authorization\internal\ReviewRoundRequiredPolicy;
+use PKP\security\authorization\WorkflowStageAccessPolicy;
+use PKP\security\Role;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\submission\SubmissionCommentDAO;
+
+class AuthorReviewerGridHandler extends PKPReviewerGridHandler
+{
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+
+        $this->addRoleAssignment(
+            [Role::ROLE_ID_AUTHOR],
+            ['fetchGrid', 'fetchRow', 'readReview', 'reviewRead']
+        );
+    }
+
+    //
+    // Overridden methods from PKPHandler
+    //
+    /**
+     * @see GridHandler::getRowInstance()
+     *
+     * @return AuthorReviewerGridRow
+     */
+    protected function getRowInstance()
+    {
+        return new AuthorReviewerGridRow();
+    }
+
+    /**
+     * @copydoc GridHandler::initialize()
+     *
+     * @param null|mixed $args
+     */
+    public function initialize($request, $args = null)
+    {
+        parent::initialize($request, $args);
+
+        // Reset actions
+        unset($this->_actions[GridHandler::GRID_ACTION_POSITION_ABOVE]);
+
+        // Columns
+        $cellProvider = new AuthorReviewerGridCellProvider();
+        $this->addColumn(
+            new GridColumn(
+                'name',
+                'user.name',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+
+        // Add a column for the status of the review.
+        $this->addColumn(
+            new GridColumn(
+                'considered',
+                'common.status',
+                null,
+                null,
+                $cellProvider,
+                ['anyhtml' => true]
+            )
+        );
+
+        // Add a column for the review method
+        $this->addColumn(
+            new GridColumn(
+                'method',
+                'common.type',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+
+        // Add a column for the status of the review.
+        $this->addColumn(
+            new GridColumn(
+                'actions',
+                'grid.columns.actions',
+                null,
+                null,
+                $cellProvider
+            )
+        );
+    }
+
+    /**
+     * @copydoc PKPHandler::authorize()
+     */
+    public function authorize($request, &$args, $roleAssignments)
+    {
+        // Bypass the parent authorization checks
+        $this->isAuthorGrid = true;
+
+        $stageId = $request->getUserVar('stageId'); // This is being validated in WorkflowStageAccessPolicy
+
+        // Not all actions need a stageId. Some work off the reviewAssignment which has the type and round.
+        $this->_stageId = (int)$stageId;
+
+        // Get the stage access policy
+        $workflowStageAccessPolicy = new WorkflowStageAccessPolicy($request, $args, $roleAssignments, 'submissionId', $stageId);
+
+        // Add policy to ensure there is a review round id.
+        $workflowStageAccessPolicy->addPolicy(new ReviewRoundRequiredPolicy($request, $args, 'reviewRoundId', ['fetchGrid', 'fetchRow']));
+
+        // Add policy to ensure there is a review assignment for certain operations.
+        $workflowStageAccessPolicy->addPolicy(new ReviewAssignmentRequiredPolicy($request, $args, 'reviewAssignmentId', ['readReview', 'reviewRead'], [ReviewAssignment::SUBMISSION_REVIEW_METHOD_OPEN]));
+        $this->addPolicy($workflowStageAccessPolicy);
+
+        return parent::authorize($request, $args, $roleAssignments);
+    }
+
+    //
+    // Overridden methods from GridHandler
+    //
+    /**
+     * @see GridHandler::loadData()
+     */
+    protected function loadData($request, $filter)
+    {
+        // Get the existing review assignments for this submission
+        // Only show open requests that have been accepted
+        $reviewRound = $this->getReviewRound();
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        return $reviewAssignmentDao->getOpenReviewsByReviewRoundId($reviewRound->getId());
+    }
+
+    /**
+     * Open a modal to read the reviewer's review and
+     * download any files they may have uploaded
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function readReview($args, $request)
+    {
+        $templateMgr = TemplateManager::getManager($request);
+        $reviewAssignment = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_REVIEW_ASSIGNMENT);
+
+        $templateMgr->assign([
+            'submission' => $this->getSubmission(),
+            'reviewAssignment' => $reviewAssignment,
+            'reviewerRecommendationOptions' => ReviewAssignment::getReviewerRecommendationOptions(),
+        ]);
+
+        if ($reviewAssignment->getReviewFormId()) {
+            // Retrieve review form
+            $context = $request->getContext();
+            $reviewFormElementDao = DAORegistry::getDAO('ReviewFormElementDAO'); /** @var ReviewFormElementDAO $reviewFormElementDao */
+            // Get review form elements visible for authors
+            $reviewFormElements = $reviewFormElementDao->getByReviewFormId($reviewAssignment->getReviewFormId(), null, true);
+            $reviewFormResponseDao = DAORegistry::getDAO('ReviewFormResponseDAO'); /** @var ReviewFormResponseDAO $reviewFormResponseDao */
+            $reviewFormResponses = $reviewFormResponseDao->getReviewReviewFormResponseValues($reviewAssignment->getId());
+            $reviewFormDao = DAORegistry::getDAO('ReviewFormDAO'); /** @var ReviewFormDAO $reviewFormDao */
+            $reviewformid = $reviewAssignment->getReviewFormId();
+            $reviewForm = $reviewFormDao->getById($reviewAssignment->getReviewFormId(), Application::getContextAssocType(), $context->getId());
+            $templateMgr->assign([
+                'reviewForm' => $reviewForm,
+                'reviewFormElements' => $reviewFormElements,
+                'reviewFormResponses' => $reviewFormResponses,
+                'disabled' => true,
+            ]);
+        } else {
+            // Retrieve reviewer comments. Skip private comments.
+            $submissionCommentDao = DAORegistry::getDAO('SubmissionCommentDAO'); /** @var SubmissionCommentDAO $submissionCommentDao */
+            $templateMgr->assign([
+                'comments' => $submissionCommentDao->getReviewerCommentsByReviewerId($reviewAssignment->getSubmissionId(), null, $reviewAssignment->getId(), true),
+            ]);
+        }
+
+        // Render the response.
+        return $templateMgr->fetchJson('controllers/grid/users/reviewer/authorReadReview.tpl');
+    }
+}

lib/pkp/controllers/grid/users/reviewer/AuthorReviewerGridRow.php

@@ -0,0 +1,23 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/AuthorReviewerGridRow.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AuthorReviewerGridRow
+ *
+ * @ingroup controllers_grid_users_reviewer
+ *
+ * @brief Reviewer grid row definition
+ */
+
+namespace PKP\controllers\grid\users\reviewer;
+
+use PKP\controllers\grid\GridRow;
+
+class AuthorReviewerGridRow extends GridRow
+{
+}

lib/pkp/controllers/grid/users/reviewer/ReviewerGridCellProvider.php

@@ -0,0 +1,221 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/ReviewerGridCellProvider.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReviewerGridCellProvider
+ *
+ * @ingroup controllers_grid_users_reviewer
+ *
+ * @brief Base class for a cell provider that can retrieve labels for reviewer grid rows
+ */
+
+namespace PKP\controllers\grid\users\reviewer;
+
+use APP\facades\Repo;
+use PKP\controllers\api\task\SendReminderLinkAction;
+use PKP\controllers\api\task\SendThankYouLinkAction;
+use PKP\controllers\grid\DataObjectGridCellProvider;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\GridHandler;
+use PKP\controllers\review\linkAction\ReviewNotesLinkAction;
+use PKP\controllers\review\linkAction\UnconsiderReviewLinkAction;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+
+class ReviewerGridCellProvider extends DataObjectGridCellProvider
+{
+    /** @var bool Is the current user assigned as an author to this submission */
+    public $_isCurrentUserAssignedAuthor;
+
+    /**
+     * Constructor
+     *
+     * @param bool $isCurrentUserAssignedAuthor Is the current user assigned
+     *  as an author to this submission?
+     */
+    public function __construct($isCurrentUserAssignedAuthor)
+    {
+        parent::__construct();
+        $this->_isCurrentUserAssignedAuthor = $isCurrentUserAssignedAuthor;
+    }
+
+    //
+    // Template methods from GridCellProvider
+    //
+    /**
+     * Gathers the state of a given cell given a $row/$column combination
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return string
+     */
+    public function getCellState($row, $column)
+    {
+        $reviewAssignment = $row->getData();
+        $columnId = $column->getId();
+        assert($reviewAssignment instanceof \PKP\core\DataObject && !empty($columnId));
+        /** @var ReviewAssignment $reviewAssignment */
+        switch ($columnId) {
+            case 'name':
+            case 'method':
+                return '';
+            case 'considered':
+            case 'actions':
+                return $reviewAssignment->getStatus();
+        }
+    }
+
+    /**
+     * Extracts variables for a given column from a data element
+     * so that they may be assigned to template before rendering.
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return array
+     */
+    public function getTemplateVarsFromRowColumn($row, $column)
+    {
+        $element = $row->getData();
+        $columnId = $column->getId();
+        assert($element instanceof \PKP\core\DataObject && !empty($columnId));
+        /** @var ReviewAssignment $element */
+        switch ($columnId) {
+            case 'name':
+                $isReviewAnonymous = in_array($element->getReviewMethod(), [ReviewAssignment::SUBMISSION_REVIEW_METHOD_ANONYMOUS, ReviewAssignment::SUBMISSION_REVIEW_METHOD_DOUBLEANONYMOUS]);
+                if ($this->_isCurrentUserAssignedAuthor && $isReviewAnonymous) {
+                    return ['label' => __('editor.review.anonymousReviewer')];
+                }
+                return ['label' => $element->getReviewerFullName()];
+
+            case 'method':
+                return ['label' => __($element->getReviewMethodKey())];
+
+            case 'considered':
+                $statusText = $this->_getStatusText($this->getCellState($row, $column), $row);
+                $reviewAssignment = $row->getData();
+                $competingInterests = $reviewAssignment->getCompetingInterests();
+                if ($competingInterests) {
+                    $statusText .= '<span class="details">' . __('reviewer.competingInterests') . '</span>';
+                }
+                return ['label' => $statusText];
+
+            case 'actions':
+                // Only attach actions to this column. See self::getCellActions()
+                return ['label' => ''];
+        }
+
+        return parent::getTemplateVarsFromRowColumn($row, $column);
+    }
+
+    /**
+     * Get cell actions associated with this row/column combination
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return array an array of LinkAction instances
+     */
+    public function getCellActions($request, $row, $column, $position = GridHandler::GRID_ACTION_POSITION_DEFAULT)
+    {
+        $reviewAssignment = $row->getData(); /** @var ReviewAssignment $reviewAssignment */
+
+        // Authors can't perform action on reviews
+        if ($this->_isCurrentUserAssignedAuthor) {
+            return [];
+        }
+
+        $actionArgs = [
+            'submissionId' => $reviewAssignment->getSubmissionId(),
+            'reviewAssignmentId' => $reviewAssignment->getId(),
+            'stageId' => $reviewAssignment->getStageId()
+        ];
+
+        $router = $request->getRouter();
+        $action = false;
+        $submission = Repo::submission()->get($reviewAssignment->getSubmissionId());
+
+        // Only attach actions to the actions column. The actions and status
+        // columns share state values.
+        $columnId = $column->getId();
+        if ($columnId == 'actions') {
+            switch ($this->getCellState($row, $column)) {
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RESPONSE_OVERDUE:
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_REVIEW_OVERDUE:
+                    return [new SendReminderLinkAction($request, 'editor.review.reminder', $actionArgs)];
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_COMPLETE:
+                    return [
+                        new SendThankYouLinkAction($request, 'editor.review.thankReviewer', $actionArgs),
+                        new UnconsiderReviewLinkAction($request, $reviewAssignment, $submission),
+                    ];
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_THANKED:
+                    return [new UnconsiderReviewLinkAction($request, $reviewAssignment, $submission)];
+                case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RECEIVED:
+                    $user = $request->getUser();
+                    return [new ReviewNotesLinkAction($request, $reviewAssignment, $submission, $user, 'grid.users.reviewer.ReviewerGridHandler', true)];
+            }
+        }
+        return parent::getCellActions($request, $row, $column, $position);
+    }
+
+    /**
+     * Provide meaningful locale keys for the various grid status states.
+     *
+     * @param string $state
+     * @param \PKP\controllers\grid\GridRow $row
+     *
+     * @return string
+     */
+    public function _getStatusText($state, $row)
+    {
+        $reviewAssignment = $row->getData();
+        switch ($state) {
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_AWAITING_RESPONSE:
+                return '<span class="state">' . __('editor.review.requestSent') . '</span><span class="details">' . __('editor.review.responseDue', ['date' => substr($reviewAssignment->getDateResponseDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_ACCEPTED:
+                return '<span class="state">' . __('editor.review.requestAccepted') . '</span><span class="details">' . __('editor.review.reviewDue', ['date' => substr($reviewAssignment->getDateDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_COMPLETE:
+                return $this->_getStatusWithRecommendation('common.complete', $reviewAssignment);
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_REVIEW_OVERDUE:
+                return '<span class="state overdue">' . __('common.overdue') . '</span><span class="details">' . __('editor.review.reviewDue', ['date' => substr($reviewAssignment->getDateDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RESPONSE_OVERDUE:
+                return '<span class="state overdue">' . __('common.overdue') . '</span><span class="details">' . __('editor.review.responseDue', ['date' => substr($reviewAssignment->getDateResponseDue(), 0, 10)]) . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_DECLINED:
+                return '<span class="state declined" title="' . __('editor.review.requestDeclined.tooltip') . '">' . __('editor.review.requestDeclined') . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_CANCELLED:
+                return '<span class="state declined" title="' . __('editor.review.requestCancelled.tooltip') . '">' . __('editor.review.requestCancelled') . '</span>';
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_RECEIVED:
+                return  $this->_getStatusWithRecommendation('editor.review.reviewSubmitted', $reviewAssignment);
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_THANKED:
+                return  $this->_getStatusWithRecommendation('editor.review.reviewerThanked', $reviewAssignment);
+            case ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_REQUEST_RESEND:
+                return '<span class="state reconsider">' . __('editor.review.ReviewerResendRequest') . '</span><span class="details">' . __('editor.review.responseDue', ['date' => substr($reviewAssignment->getDateDue(), 0, 10)]) . '</span>';
+            default:
+                return '';
+        }
+    }
+
+    /**
+     * Retrieve a formatted HTML string that displays the state of the review
+     * with the review recommendation if one exists. Or return just the state.
+     * Only works with some states.
+     *
+     * @param string $statusKey Locale key for status text
+     * @param \PKP\submission\reviewAssignment\ReviewAssignment $reviewAssignment
+     *
+     * @return string
+     */
+    public function _getStatusWithRecommendation($statusKey, $reviewAssignment)
+    {
+        if (!$reviewAssignment->getRecommendation()) {
+            return __($statusKey);
+        }
+
+        return '<span class="state">' . __($statusKey) . '</span><span class="details">' . __('submission.recommendation', ['recommendation' => $reviewAssignment->getLocalizedRecommendation()]) . '</span>';
+    }
+}

lib/pkp/controllers/grid/users/reviewer/ReviewerGridRow.php

@@ -0,0 +1,220 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/ReviewerGridRow.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReviewerGridRow
+ *
+ * @ingroup controllers_grid_users_reviewer
+ *
+ * @brief Reviewer grid row definition
+ */
+
+namespace PKP\controllers\grid\users\reviewer;
+
+use APP\facades\Repo;
+use PKP\controllers\grid\GridRow;
+use PKP\core\PKPApplication;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+use PKP\linkAction\request\RedirectConfirmationModal;
+use PKP\security\Validation;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+
+class ReviewerGridRow extends GridRow
+{
+    /** @var bool Is the current user assigned as an author to this submission */
+    public $_isCurrentUserAssignedAuthor;
+
+    /**
+     * Constructor
+     *
+     * @param bool $isCurrentUserAssignedAuthor Is the current user assigned as an
+     *  author to this submission?
+     */
+    public function __construct($isCurrentUserAssignedAuthor)
+    {
+        parent::__construct();
+        $this->_isCurrentUserAssignedAuthor = $isCurrentUserAssignedAuthor;
+    }
+
+    //
+    // Overridden methods from GridRow
+    //
+    /**
+     * @copydoc GridRow::initialize()
+     *
+     * @param null|mixed $template
+     */
+    public function initialize($request, $template = null)
+    {
+        parent::initialize($request, $template);
+
+        // Retrieve the submission id from the request
+        // These parameters need not be validated as we're just
+        // passing them along to another request, where they will be
+        // checked before they're used.
+        $submissionId = (int) $request->getUserVar('submissionId');
+        $stageId = (int) $request->getUserVar('stageId');
+        $round = (int) $request->getUserVar('round');
+
+        // Authors can't perform any actions on anonymous reviews
+        $reviewAssignment = $this->getData(); /** @var ReviewAssignment $reviewAssignment */
+        $isReviewAnonymous = in_array($reviewAssignment->getReviewMethod(), [ReviewAssignment::SUBMISSION_REVIEW_METHOD_ANONYMOUS, ReviewAssignment::SUBMISSION_REVIEW_METHOD_DOUBLEANONYMOUS]);
+        if ($this->_isCurrentUserAssignedAuthor && $isReviewAnonymous) {
+            return;
+        }
+
+        // Is this a new row or an existing row?
+        $rowId = $this->getId();
+        if (!empty($rowId) && is_numeric($rowId)) {
+            // Only add row actions if this is an existing row
+            $router = $request->getRouter();
+            $actionArgs = [
+                'submissionId' => $submissionId,
+                'reviewAssignmentId' => $rowId,
+                'stageId' => $stageId,
+                'round' => $round
+            ];
+
+            // read or upload a review
+            $submission = Repo::submission()->get($submissionId);
+            if (!$reviewAssignment->getCancelled()) {
+                $this->addAction(
+                    new LinkAction(
+                        'readReview',
+                        new AjaxModal(
+                            $router->url($request, null, null, 'readReview', null, $actionArgs),
+                            __('editor.review.reviewDetails') . ': ' . $submission->getCurrentPublication()->getLocalizedTitle(null, 'html'),
+                            'modal_information'
+                        ),
+                        __('editor.review.reviewDetails'),
+                        'more_info'
+                    )
+                );
+            }
+
+            $this->addAction(
+                new LinkAction(
+                    'email',
+                    new AjaxModal(
+                        $router->url($request, null, null, 'sendEmail', null, $actionArgs),
+                        __('editor.review.emailReviewer'),
+                        'modal_email'
+                    ),
+                    __('editor.review.emailReviewer'),
+                    'notify'
+                )
+            );
+
+            if (!$this->_isCurrentUserAssignedAuthor) {
+                if ($reviewAssignment->canResendReviewRequest()) {
+                    $this->addAction(
+                        new LinkAction(
+                            'resendRequestReviewer',
+                            new AjaxModal(
+                                $router->url($request, null, null, 'resendRequestReviewer', null, $actionArgs),
+                                __('editor.review.resendRequestReviewer'),
+                                'modal_add'
+                            ),
+                            __('editor.review.resendRequestReviewer'),
+                            'add'
+                        )
+                    );
+                }
+
+                if (!$reviewAssignment->getCancelled()) {
+                    $this->addAction(new LinkAction(
+                        'manageAccess',
+                        new AjaxModal(
+                            $router->url($request, null, null, 'editReview', null, $actionArgs),
+                            __('editor.submissionReview.editReview'),
+                            'modal_add_file'
+                        ),
+                        __('common.edit'),
+                        'edit'
+                    ));
+                    $this->addAction(new LinkAction(
+                        'unassignReviewer',
+                        new AjaxModal(
+                            $router->url($request, null, null, 'unassignReviewer', null, $actionArgs),
+                            $reviewAssignment->getDateConfirmed() ? __('editor.review.cancelReviewer') : __('editor.review.unassignReviewer'),
+                            'modal_delete'
+                        ),
+                        $reviewAssignment->getDateConfirmed() ? __('editor.review.cancelReviewer') : __('editor.review.unassignReviewer'),
+                        'delete'
+                    ));
+                } else {
+                    $this->addAction(
+                        new LinkAction(
+                            'reinstateReviewer',
+                            new AjaxModal(
+                                $router->url($request, null, null, 'reinstateReviewer', null, $actionArgs),
+                                __('editor.review.reinstateReviewer'),
+                                'modal_add'
+                            ),
+                            __('editor.review.reinstateReviewer'),
+                            'add'
+                        )
+                    );
+                }
+            }
+
+            $this->addAction(
+                new LinkAction(
+                    'history',
+                    new AjaxModal(
+                        $router->url($request, null, null, 'reviewHistory', null, $actionArgs),
+                        __('submission.history'),
+                        'modal_information'
+                    ),
+                    __('submission.history'),
+                    'more_info'
+                )
+            );
+
+            $user = $request->getUser();
+            if (
+                !Validation::loggedInAs() &&
+                $user->getId() != $reviewAssignment->getReviewerId() &&
+                Validation::getAdministrationLevel($reviewAssignment->getReviewerId(), $user->getId()) === Validation::ADMINISTRATION_FULL &&
+                !$reviewAssignment->getCancelled()
+            ) {
+                $dispatcher = $router->getDispatcher();
+                $this->addAction(
+                    new LinkAction(
+                        'logInAs',
+                        new RedirectConfirmationModal(
+                            __('grid.user.confirmLogInAs'),
+                            __('grid.action.logInAs'),
+                            $dispatcher->url($request, PKPApplication::ROUTE_PAGE, null, 'login', 'signInAsUser', $reviewAssignment->getReviewerId())
+                        ),
+                        __('grid.action.logInAs'),
+                        'enroll_user'
+                    )
+                );
+            }
+
+            // Add gossip action when appropriate
+            $canCurrentUserGossip = Repo::user()->canCurrentUserGossip($reviewAssignment->getReviewerId());
+            if ($canCurrentUserGossip) {
+                $this->addAction(
+                    new LinkAction(
+                        'gossip',
+                        new AjaxModal(
+                            $router->url($request, null, null, 'gossip', null, $actionArgs),
+                            __('user.gossip'),
+                            'modal_information'
+                        ),
+                        __('user.gossip'),
+                        'more_info'
+                    )
+                );
+            }
+        }
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/AdvancedSearchReviewerForm.php

@@ -0,0 +1,263 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/AdvancedSearchReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AdvancedSearchReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for an advanced search and for adding a reviewer to a submission.
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\core\Request;
+use APP\core\Services;
+use APP\facades\Repo;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\controllers\grid\users\reviewer\PKPReviewerGridHandler;
+use PKP\core\PKPApplication;
+use PKP\db\DAORegistry;
+use PKP\emailTemplate\EmailTemplate;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxAction;
+use PKP\mail\mailables\ReviewRequest;
+use PKP\mail\mailables\ReviewRequestSubsequent;
+use PKP\security\Role;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\submission\reviewRound\ReviewRound;
+use PKP\submission\reviewRound\ReviewRoundDAO;
+
+class AdvancedSearchReviewerForm extends ReviewerForm
+{
+    /**
+     * Constructor.
+     *
+     * @param Submission $submission
+     * @param ReviewRound $reviewRound
+     */
+    public function __construct($submission, $reviewRound)
+    {
+        parent::__construct($submission, $reviewRound);
+        $this->setTemplate('controllers/grid/users/reviewer/form/advancedSearchReviewerForm.tpl');
+
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'reviewerId', 'required', 'editor.review.mustSelect'));
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        parent::readInputData();
+
+        $this->readUserVars(['reviewerId']);
+    }
+
+    /**
+     * @copydoc Form::initData()
+     */
+    public function initData()
+    {
+        parent::initData();
+
+        $request = Application::get()->getRequest();
+        $context = $request->getContext();
+        $mailable = $this->getMailable();
+
+        $templates = Repo::emailTemplate()->getCollector($context->getId())
+            ->filterByKeys([ReviewRequest::getEmailTemplateKey(), ReviewRequestSubsequent::getEmailTemplateKey()])
+            ->getMany()
+            ->mapWithKeys(function (EmailTemplate $item, int $key) use ($mailable) {
+                return [$item->getData('key') => Mail::compileParams($item->getLocalizedData('body'), $mailable->viewData)];
+            });
+
+        $this->setData('personalMessage', '');
+        $this->setData('reviewerMessages', $templates->toArray());
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        // Get submission context
+        $submissionContext = Services::get('context')->get($this->getSubmission()->getContextId());
+
+        // Pass along the request vars
+        $actionArgs = $request->getUserVars();
+        $reviewRound = $this->getReviewRound();
+        $actionArgs['reviewRoundId'] = $reviewRound->getId();
+        $actionArgs['selectionType'] = PKPReviewerGridHandler::REVIEWER_SELECT_ADVANCED_SEARCH;
+        // but change the selectionType for each action
+        $advancedSearchAction = new LinkAction(
+            'advancedSearch',
+            new AjaxAction($request->url(null, null, 'reloadReviewerForm', null, $actionArgs)),
+            __('manager.reviewerSearch.change'),
+            'user_search'
+        );
+
+        $this->setReviewerFormAction($advancedSearchAction);
+
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+
+        // get reviewer IDs already assign to this submission and this round
+        $reviewAssignments = $reviewAssignmentDao->getBySubmissionId($this->getSubmissionId(), $this->getReviewRound()->getId());
+        $currentlyAssigned = [];
+        if (!empty($reviewAssignments)) {
+            foreach ($reviewAssignments as $reviewAssignment) {
+                $currentlyAssigned[] = (int) $reviewAssignment->getReviewerId();
+            }
+        }
+
+        // Get user IDs already assigned to this submission, and admins and
+        // managers who may have access to author identities and can not guarantee
+        // anonymous reviews
+        $warnOnAssignment = [];
+        $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+        $stageAssignmentResults = $stageAssignmentDao->getBySubmissionAndStageId($this->getSubmissionId());
+        while ($stageAssignment = $stageAssignmentResults->next()) {
+            $warnOnAssignment[] = $stageAssignment->getUserId();
+        }
+
+        // Get a list of users in the managerial and admin user groups
+        // Managers are assigned only to contexts; site admins are assigned only to site.
+        // Therefore filtering by both context IDs and role IDs will not cause problems.
+        $userIds = Repo::user()->getCollector()
+            ->filterByRoleIds([Role::ROLE_ID_MANAGER, Role::ROLE_ID_SITE_ADMIN])
+            ->filterByContextIds([$submissionContext->getId(), PKPApplication::CONTEXT_SITE])
+            ->getIds()
+            ->toArray();
+        $warnOnAssignment = array_merge($warnOnAssignment, $userIds);
+        $warnOnAssignment = array_values(array_unique(array_map('intval', $warnOnAssignment)));
+
+        // Get reviewers list
+        $selectReviewerListPanel = new \PKP\components\listPanels\PKPSelectReviewerListPanel(
+            'selectReviewer',
+            __('editor.submission.findAndSelectReviewer'),
+            [
+                'apiUrl' => $request->getDispatcher()->url(
+                    $request,
+                    PKPApplication::ROUTE_API,
+                    $submissionContext->getPath(),
+                    'users/reviewers'
+                ),
+                'currentlyAssigned' => $currentlyAssigned,
+                'getParams' => [
+                    'contextId' => $submissionContext->getId(),
+                    'reviewStage' => $reviewRound->getStageId(),
+                ],
+                'selectorName' => 'reviewerId',
+                'warnOnAssignment' => $warnOnAssignment,
+            ]
+        );
+
+        // Get reviewers who completed a review in the last round
+        $lastRoundReviewerIds = [];
+        if ($this->getReviewRound()->getRound() > 1) {
+            /** @var ReviewRoundDAO */
+            $reviewRoundDao = DAORegistry::getDAO('ReviewRoundDAO');
+            $previousRound = $this->getReviewRound()->getRound() - 1;
+            $lastReviewRound = $reviewRoundDao->getReviewRound($this->getSubmissionId(), $this->getReviewRound()->getStageId(), $previousRound);
+
+            if ($lastReviewRound) {
+                $lastReviewAssignments = $reviewAssignmentDao->getByReviewRoundId($lastReviewRound->getId());
+                foreach ($lastReviewAssignments as $reviewAssignment) {
+                    if (in_array($reviewAssignment->getStatus(), [ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_THANKED, ReviewAssignment::REVIEW_ASSIGNMENT_STATUS_COMPLETE])) {
+                        $lastRoundReviewerIds[] = (int) $reviewAssignment->getReviewerId();
+                    }
+                }
+
+                $lastRoundReviewers = Repo::user()->getCollector()
+                    ->filterByContextIds([$submissionContext->getId()])
+                    ->filterByRoleIds([Role::ROLE_ID_REVIEWER])
+                    ->filterByUserIds($lastRoundReviewerIds)
+                    ->includeReviewerData()
+                    ->getMany();
+
+                if (count($lastRoundReviewers)) {
+                    $selectReviewerListPanel->set([
+                        'lastRoundReviewers' => $lastRoundReviewers,
+                    ]);
+                }
+            }
+        }
+
+        $templateMgr = TemplateManager::getManager($request);
+        // Used to determine the right email template
+        $templateMgr->assign('lastRoundReviewerIds', $lastRoundReviewerIds);
+
+        $selectReviewerListPanel->set([
+            'items' => $selectReviewerListPanel->getItems($request),
+            'itemsMax' => $selectReviewerListPanel->getItemsMax(),
+        ]);
+
+        $templateMgr->assign('selectReviewerListData', [
+            'components' => [
+                'selectReviewer' => $selectReviewerListPanel->getConfig(),
+            ]
+        ]);
+
+        // Only add actions to forms where user can operate.
+        if (array_intersect($this->getUserRoles(), [Role::ROLE_ID_MANAGER, Role::ROLE_ID_SUB_EDITOR])) {
+            $actionArgs['selectionType'] = PKPReviewerGridHandler::REVIEWER_SELECT_CREATE;
+            // but change the selectionType for each action
+            $advancedSearchAction = new LinkAction(
+                'selectCreate',
+                new AjaxAction($request->url(null, null, 'reloadReviewerForm', null, $actionArgs)),
+                __('editor.review.createReviewer'),
+                'add_user'
+            );
+
+            $this->setReviewerFormAction($advancedSearchAction);
+            $actionArgs['selectionType'] = PKPReviewerGridHandler::REVIEWER_SELECT_ENROLL_EXISTING;
+            // but change the selectionType for each action
+            $advancedSearchAction = new LinkAction(
+                'enrolExisting',
+                new AjaxAction($request->url(null, null, 'reloadReviewerForm', null, $actionArgs)),
+                __('editor.review.enrollReviewer.short'),
+                'enroll_user'
+            );
+
+            $this->setReviewerFormAction($advancedSearchAction);
+        }
+
+        return parent::fetch($request, $template, $display);
+    }
+
+    protected function getEmailTemplates(): array
+    {
+        $subsequentTemplate = Repo::emailTemplate()->getByKey(
+            Application::get()->getRequest()->getContext()->getId(),
+            ReviewRequestSubsequent::getEmailTemplateKey()
+        );
+
+        $alternateTemplates = Repo::emailTemplate()->getCollector(Application::get()->getRequest()->getContext()->getId())
+            ->alternateTo([ReviewRequestSubsequent::getEmailTemplateKey()])
+            ->getMany();
+
+        $templateKeys = array_merge(
+            parent::getEmailTemplates(),
+            [ReviewRequestSubsequent::getEmailTemplateKey() => $subsequentTemplate->getLocalizedData('name')]
+        );
+
+        foreach ($alternateTemplates as $alternateTemplate) {
+            $templateKeys[$alternateTemplate->getData('key')] = $alternateTemplate->getLocalizedData('name');
+        }
+
+        return $templateKeys;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/CreateReviewerForm.php

@@ -0,0 +1,180 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/CreateReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class CreateReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for creating and subsequently adding a reviewer to a submission.
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\core\Core;
+use PKP\mail\mailables\ReviewerRegister;
+use PKP\notification\PKPNotification;
+use PKP\security\Validation;
+use PKP\submission\reviewRound\ReviewRound;
+use PKP\user\InterestManager;
+use Symfony\Component\Mailer\Exception\TransportException;
+
+class CreateReviewerForm extends ReviewerForm
+{
+    /**
+     * Constructor.
+     *
+     * @param Submission $submission
+     * @param ReviewRound $reviewRound
+     */
+    public function __construct($submission, $reviewRound)
+    {
+        parent::__construct($submission, $reviewRound);
+        $this->setTemplate('controllers/grid/users/reviewer/form/createReviewerForm.tpl');
+
+        // the users register for the site, thus
+        // the site primary locale is the required default locale
+        $site = Application::get()->getRequest()->getSite();
+        $this->addSupportedFormLocale($site->getPrimaryLocale());
+
+        $form = $this;
+        $this->addCheck(new \PKP\form\validation\FormValidatorLocale($this, 'givenName', 'required', 'user.profile.form.givenNameRequired', $site->getPrimaryLocale()));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCustom($this, 'familyName', 'optional', 'user.profile.form.givenNameRequired.locale', function ($familyName) use ($form) {
+            $givenNames = $form->getData('givenName');
+            foreach ($familyName as $locale => $value) {
+                if (!empty($value) && empty($givenNames[$locale])) {
+                    return false;
+                }
+            }
+            return true;
+        }));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCustom($this, 'username', 'required', 'user.register.form.usernameExists', [Repo::user(), 'getByUsername'], [true], true));
+        $this->addCheck(new \PKP\form\validation\FormValidatorUsername($this, 'username', 'required', 'user.register.form.usernameAlphaNumeric'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorEmail($this, 'email', 'required', 'user.profile.form.emailRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCustom($this, 'email', 'required', 'user.register.form.emailExists', function ($email) {
+            return !Repo::user()->getByEmail($email, true);
+        }));
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'userGroupId', 'required', 'user.profile.form.usergroupRequired'));
+    }
+
+    /**
+     * @copydoc Form::init()
+     */
+    public function initData()
+    {
+        parent::initData();
+
+        $mailable = $this->getMailable();
+        $context = Application::get()->getRequest()->getContext();
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+        $this->setData('personalMessage', Mail::compileParams($template->getLocalizedData('body'), $mailable->viewData));
+    }
+
+    /**
+     * @copydoc ReviewerForm::fetch
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $advancedSearchAction = $this->getAdvancedSearchAction($request);
+        $this->setReviewerFormAction($advancedSearchAction);
+        $site = $request->getSite();
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign('sitePrimaryLocale', $site->getPrimaryLocale());
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        parent::readInputData();
+
+        $this->readUserVars([
+            'givenName',
+            'familyName',
+            'affiliation',
+            'interests',
+            'username',
+            'email',
+            'skipEmail',
+            'userGroupId',
+        ]);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionArgs)
+    {
+        $user = Repo::user()->newDataObject();
+
+        $user->setGivenName($this->getData('givenName'), null);
+        $user->setFamilyName($this->getData('familyName'), null);
+        $user->setEmail($this->getData('email'));
+        $user->setAffiliation($this->getData('affiliation'), null); // Localized
+        $user->setInlineHelp(1); // default new reviewers to having inline help visible
+
+        $user->setUsername($this->getData('username'));
+        $password = Validation::generatePassword();
+
+        $user->setPassword(Validation::encryptCredentials($this->getData('username'), $password));
+        $user->setMustChangePassword(true); // Emailed P/W not safe
+
+        $user->setDateRegistered(Core::getCurrentDate());
+        $reviewerId = Repo::user()->add($user);
+
+        // Set the reviewerId in the Form for the parent class to use
+        $this->setData('reviewerId', $reviewerId);
+
+        // Insert the user interests
+        $interestManager = new InterestManager();
+        $interestManager->setInterestsForUser($user, $this->getData('interests'));
+
+        // Assign the selected user group ID to the user
+        $userGroupId = (int) $this->getData('userGroupId');
+        Repo::userGroup()->assignUserToGroup($reviewerId, $userGroupId);
+
+        if (!$this->getData('skipEmail')) {
+            // Send welcome email to user
+            $request = Application::get()->getRequest();
+            $context = $request->getContext();
+            $mailable = new ReviewerRegister($context, $password);
+            $mailable->recipients($user);
+            $mailable->sender($request->getUser());
+            $mailable->replyTo($context->getData('contactEmail'), $context->getData('contactName'));
+            $template = Repo::emailTemplate()->getByKey($context->getId(), ReviewerRegister::getEmailTemplateKey());
+            $mailable->subject($template->getLocalizedData('subject'));
+            $mailable->body($template->getLocalizedData('body'));
+
+            try {
+                Mail::send($mailable);
+            } catch (TransportException $e) {
+                $notificationMgr = new NotificationManager();
+                $notificationMgr->createTrivialNotification(
+                    $request->getUser()->getId(),
+                    PKPNotification::NOTIFICATION_TYPE_ERROR,
+                    ['contents' => __('email.compose.error')]
+                );
+                error_log($e->getMessage());
+            }
+        }
+
+        return parent::execute(...$functionArgs);
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/EditReviewForm.php

@@ -0,0 +1,235 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/EditReviewForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class EditReviewForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Allow the editor to limit the available files to an assigned
+ * reviewer after the assignment has taken place.
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\Notification;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\core\PKPApplication;
+use PKP\db\DAORegistry;
+use PKP\form\Form;
+use PKP\mail\mailables\EditReviewNotify;
+use PKP\notification\NotificationSubscriptionSettingsDAO;
+use PKP\notification\PKPNotification;
+use PKP\reviewForm\ReviewFormDAO;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\submission\ReviewFilesDAO;
+use PKP\submission\reviewRound\ReviewRound;
+use PKP\submission\reviewRound\ReviewRoundDAO;
+use PKP\submissionFile\SubmissionFile;
+
+class EditReviewForm extends Form
+{
+    /** @var ReviewAssignment */
+    public $_reviewAssignment;
+
+    /** @var ReviewRound */
+    public $_reviewRound;
+
+    protected Submission $submission;
+
+    public function __construct(ReviewAssignment $reviewAssignment, Submission $submission)
+    {
+        $this->_reviewAssignment = $reviewAssignment;
+        $this->submission = $submission;
+        assert($this->_reviewAssignment instanceof ReviewAssignment);
+
+        $reviewRoundDao = DAORegistry::getDAO('ReviewRoundDAO'); /** @var ReviewRoundDAO $reviewRoundDao */
+        $this->_reviewRound = $reviewRoundDao->getById($reviewAssignment->getReviewRoundId());
+        assert(is_a($this->_reviewRound, 'ReviewRound'));
+
+        parent::__construct('controllers/grid/users/reviewer/form/editReviewForm.tpl');
+
+        // Validation checks for this form
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'responseDueDate', 'required', 'editor.review.errorAddingReviewer'));
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'reviewDueDate', 'required', 'editor.review.errorAddingReviewer'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    //
+    // Overridden template methods
+    //
+    /**
+     * Initialize form data from the associated author.
+     */
+    public function initData()
+    {
+        $this->setData('responseDueDate', $this->_reviewAssignment->getDateResponseDue());
+        $this->setData('reviewDueDate', $this->_reviewAssignment->getDateDue());
+        return parent::initData();
+    }
+
+    /**
+     * Fetch the Edit Review Form form
+     *
+     * @see Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $templateMgr = TemplateManager::getManager($request);
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $context = $request->getContext();
+
+        if (!$this->_reviewAssignment->getDateCompleted()) {
+            $reviewFormDao = DAORegistry::getDAO('ReviewFormDAO'); /** @var ReviewFormDAO $reviewFormDao */
+            $reviewFormsIterator = $reviewFormDao->getActiveByAssocId(Application::getContextAssocType(), $context->getId());
+            $reviewForms = [];
+            while ($reviewForm = $reviewFormsIterator->next()) {
+                $reviewForms[$reviewForm->getId()] = $reviewForm->getLocalizedTitle();
+            }
+            $templateMgr->assign([
+                'reviewForms' => $reviewForms,
+                'reviewFormId' => $this->_reviewAssignment->getReviewFormId(),
+            ]);
+        }
+
+        $templateMgr->assign([
+            'stageId' => $this->_reviewAssignment->getStageId(),
+            'reviewRoundId' => $this->_reviewRound->getId(),
+            'submissionId' => $this->_reviewAssignment->getSubmissionId(),
+            'reviewAssignmentId' => $this->_reviewAssignment->getId(),
+            'reviewMethod' => $this->_reviewAssignment->getReviewMethod(),
+            'reviewMethods' => $reviewAssignmentDao->getReviewMethodsTranslationKeys(),
+        ]);
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'selectedFiles',
+            'responseDueDate',
+            'reviewDueDate',
+            'reviewMethod',
+            'reviewFormId',
+
+        ]);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionArgs)
+    {
+        $request = Application::get()->getRequest();
+        $context = $request->getContext();
+
+        // Revoke all, then grant selected.
+        $reviewFilesDao = DAORegistry::getDAO('ReviewFilesDAO'); /** @var ReviewFilesDAO $reviewFilesDao */
+        $reviewFilesDao->revokeByReviewId($this->_reviewAssignment->getId());
+
+        $fileStages = [$this->_reviewRound->getStageId() == WORKFLOW_STAGE_ID_INTERNAL_REVIEW ? SubmissionFile::SUBMISSION_FILE_INTERNAL_REVIEW_FILE : SubmissionFile::SUBMISSION_FILE_REVIEW_FILE];
+        $submissionFiles = Repo::submissionFile()
+            ->getCollector()
+            ->filterBySubmissionIds([$this->_reviewAssignment->getSubmissionId()])
+            ->filterByReviewRoundIds([$this->_reviewRound->getId()])
+            ->filterByFileStages($fileStages)
+            ->getMany();
+
+        $selectedFiles = array_map(function ($id) {
+            return (int) $id;
+        }, (array) $this->getData('selectedFiles'));
+        foreach ($submissionFiles as $submissionFile) {
+            if (in_array($submissionFile->getId(), $selectedFiles)) {
+                $reviewFilesDao->grant($this->_reviewAssignment->getId(), $submissionFile->getId());
+            }
+        }
+
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $reviewAssignment = $reviewAssignmentDao->getReviewAssignment($this->_reviewRound->getId(), $this->_reviewAssignment->getReviewerId());
+
+        // Send notification to reviewer if details have changed.
+        if (strtotime($reviewAssignment->getDateDue()) != strtotime($this->getData('reviewDueDate')) || strtotime($reviewAssignment->getDateResponseDue()) != strtotime($this->getData('responseDueDate')) || $reviewAssignment->getReviewMethod() != $this->getData('reviewMethod')) {
+            $notificationManager = new NotificationManager();
+            $request = Application::get()->getRequest();
+            $context = $request->getContext();
+
+            $notification = $notificationManager->createNotification(
+                $request,
+                $reviewAssignment->getReviewerId(),
+                PKPNotification::NOTIFICATION_TYPE_REVIEW_ASSIGNMENT_UPDATED,
+                $context->getId(),
+                PKPApplication::ASSOC_TYPE_REVIEW_ASSIGNMENT,
+                $reviewAssignment->getId(),
+                Notification::NOTIFICATION_LEVEL_TASK
+            );
+
+            // Check if user is subscribed to this type of notification emails
+            $reviewer = Repo::user()->get($reviewAssignment->getReviewerId());
+            /** @var NotificationSubscriptionSettingsDAO */
+            $notificationSubscriptionSettingsDao = DAORegistry::getDAO('NotificationSubscriptionSettingsDAO');
+            if ($notification && !in_array(
+                PKPNotification::NOTIFICATION_TYPE_REVIEW_ASSIGNMENT_UPDATED,
+                $notificationSubscriptionSettingsDao->getNotificationSubscriptionSettings(
+                    NotificationSubscriptionSettingsDAO::BLOCKED_EMAIL_NOTIFICATION_KEY,
+                    $reviewer->getId(),
+                    (int) $context->getId()
+                )
+            )
+            ) {
+                $mailable = new EditReviewNotify($context, $this->submission, $reviewAssignment);
+                $template = Repo::emailTemplate()->getByKey($context->getId(), EditReviewNotify::getEmailTemplateKey());
+
+                // The template may not exist, see pkp/pkp-lib#9109
+                if (!$template) {
+                    $template = Repo::emailTemplate()->getByKey($context->getId(), 'NOTIFICATION');
+                    $mailable->addData([
+                        'notificationContents' => $notificationManager->getNotificationContents($request, $notification),
+                        'notificationUrl' => $notificationManager->getNotificationUrl($request, $notification),
+                    ]);
+                }
+                $mailable
+                    ->sender($request->getUser())
+                    ->recipients([$reviewer])
+                    ->subject($template->getLocalizedData('subject'))
+                    ->body($template->getLocalizedData('body'))
+                    ->allowUnsubscribe($notification);
+
+                Mail::send($mailable);
+            }
+        }
+
+        $reviewAssignment->setDateDue($this->getData('reviewDueDate'));
+        $reviewAssignment->setDateResponseDue($this->getData('responseDueDate'));
+        $reviewAssignment->setReviewMethod($this->getData('reviewMethod'));
+
+        if (!$reviewAssignment->getDateCompleted()) {
+            // Ensure that the review form ID is valid, if specified
+            $reviewFormId = (int) $this->getData('reviewFormId');
+            $reviewFormDao = DAORegistry::getDAO('ReviewFormDAO'); /** @var ReviewFormDAO $reviewFormDao */
+            $reviewForm = $reviewFormDao->getById($reviewFormId, Application::getContextAssocType(), $context->getId());
+            $reviewAssignment->setReviewFormId($reviewForm ? $reviewFormId : null);
+        }
+
+        $reviewAssignmentDao->updateObject($reviewAssignment);
+        parent::execute(...$functionArgs);
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/EmailReviewerForm.php

@@ -0,0 +1,130 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/EmailReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class EmailReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for sending an email to a user
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\db\DAORegistry;
+use PKP\form\Form;
+use PKP\log\SubmissionEmailLogDAO;
+use PKP\log\SubmissionEmailLogEntry;
+use PKP\mail\Mailable;
+use PKP\notification\PKPNotification;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use Symfony\Component\Mailer\Exception\TransportException;
+
+class EmailReviewerForm extends Form
+{
+    /** @var ReviewAssignment The review assignment to use for this contact */
+    public $_reviewAssignment;
+
+    protected Submission $submission;
+
+    /**
+     * Constructor.
+     *
+     * @param ReviewAssignment $reviewAssignment The review assignment to use for this contact.
+     * @param Submission $submission
+     */
+    public function __construct($reviewAssignment, $submission)
+    {
+        parent::__construct('controllers/grid/users/reviewer/form/emailReviewerForm.tpl');
+
+        $this->_reviewAssignment = $reviewAssignment;
+        $this->submission = $submission;
+
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'subject', 'required', 'email.subjectRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'message', 'required', 'email.bodyRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'subject',
+            'message',
+        ]);
+    }
+
+    /**
+     * Display the form.
+     *
+     * @param array $requestArgs Request parameters to bounce back with the form submission.
+     * @param null|mixed $template
+     *
+     * @see Form::fetch
+     */
+    public function fetch($request, $template = null, $display = false, $requestArgs = [])
+    {
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign([
+            'userFullName' => $this->_reviewAssignment->getReviewerFullName(),
+            'requestArgs' => $requestArgs,
+            'reviewAssignmentId' => $this->_reviewAssignment->getId(),
+        ]);
+
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Send the email
+     */
+    public function execute(...$functionArgs)
+    {
+        $toUser = Repo::user()->get($this->_reviewAssignment->getReviewerId());
+        $request = Application::get()->getRequest();
+        $fromUser = $request->getUser();
+
+        $mailable = new Mailable([$request->getContext(), $this->submission]);
+        $mailable->to($toUser->getEmail(), $toUser->getFullName());
+        $mailable->from($fromUser->getEmail(), $fromUser->getFullName());
+        $mailable->replyTo($fromUser->getEmail(), $fromUser->getFullName());
+        $mailable->subject($this->getData('subject'));
+        $mailable->body($this->getData('message'));
+
+        try {
+            Mail::send($mailable);
+            $submissionEmailLogDao = DAORegistry::getDAO('SubmissionEmailLogDAO'); /** @var SubmissionEmailLogDAO $submissionEmailLogDao */
+            $submissionEmailLogDao->logMailable(
+                SubmissionEmailLogEntry::SUBMISSION_EMAIL_REVIEW_NOTIFY_REVIEWER,
+                $mailable,
+                $this->submission,
+                $fromUser,
+            );
+        } catch (TransportException $e) {
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification(
+                $fromUser->getId(),
+                PKPNotification::NOTIFICATION_TYPE_ERROR,
+                ['contents' => __('email.compose.error')]
+            );
+            trigger_error($e->getMessage(), E_USER_WARNING);
+        }
+
+        parent::execute(...$functionArgs);
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/EnrollExistingReviewerForm.php

@@ -0,0 +1,137 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/EnrollExistingReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class EnrollExistingReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for enrolling an existing reviewer and adding them to a submission.
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use Illuminate\Support\Facades\Mail;
+use PKP\db\DAORegistry;
+use PKP\security\Role;
+use PKP\security\RoleDAO;
+
+class EnrollExistingReviewerForm extends ReviewerForm
+{
+    /**
+     * Constructor.
+     */
+    public function __construct($submission, $reviewRound)
+    {
+        parent::__construct($submission, $reviewRound);
+        $this->setTemplate('controllers/grid/users/reviewer/form/enrollExistingReviewerForm.tpl');
+
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'userGroupId', 'required', 'user.profile.form.usergroupRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'userId', 'required', 'manager.people.existingUserRequired'));
+    }
+
+    /**
+     * @copydoc Form::init()
+     */
+    public function initData()
+    {
+        parent::initData();
+
+        $mailable = $this->getMailable();
+        $context = Application::get()->getRequest()->getContext();
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+        $this->setData('personalMessage', Mail::compileParams($template->getLocalizedData('body'), $mailable->viewData));
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $advancedSearchAction = $this->getAdvancedSearchAction($request);
+
+        $this->setReviewerFormAction($advancedSearchAction);
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        parent::readInputData();
+
+        $this->readUserVars(['userId', 'userGroupId']);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionArgs)
+    {
+        // Assign a reviewer user group to an existing non-reviewer
+        $userId = (int) $this->getData('userId');
+
+        $userGroupId = (int) $this->getData('userGroupId');
+
+        if (!$this->isValidUserAndGroup($userId, $userGroupId)) {
+            fatalError('invalid user or userGroup ID');
+        }
+
+        Repo::userGroup()->assignUserToGroup($userId, $userGroupId);
+
+        // Set the reviewerId in the Form for the parent class to use
+        $this->setData('reviewerId', $userId);
+
+        return parent::execute(...$functionArgs);
+    }
+
+    /**
+     * Checks if the user group is valid and the user exists and doesn't already have a reviewer role
+     */
+    protected function isValidUserAndGroup(int $userId, int $userGroupId): bool
+    {
+        $context = Application::get()->getRequest()->getContext();
+
+        // User exists
+        $user = Repo::user()->get($userId);
+        if (!$user) {
+            return false;
+        }
+
+        // Ensure user doesn't have a reviewer role
+        $roleDao = DAORegistry::getDAO('RoleDAO'); /** @var RoleDAO $roleDao */
+        if ($roleDao->userHasRole($context->getId(), $user->getId(), Role::ROLE_ID_REVIEWER)) {
+            return false;
+        }
+
+        // User Group exists
+        $userGroup = Repo::userGroup()->get($userGroupId);
+        if (!$userGroup) {
+            return false;
+        }
+
+        // User Group refers to the reviewer role
+        if ($userGroup->getData('roleId') != Role::ROLE_ID_REVIEWER) {
+            return false;
+        }
+
+        // User group refers to the right context
+        if (intval($userGroup->getData('contextId')) != $context->getId()) {
+            return false;
+        }
+
+        return true;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ReinstateReviewerForm.php

@@ -0,0 +1,112 @@
+<?php
+/**
+ * @file controllers/grid/users/reviewer/form/ReinstateReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReinstateReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Allow the editor to reinstate a cancelled review assignment
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use PKP\context\Context;
+use PKP\core\Core;
+use PKP\core\PKPApplication;
+use PKP\db\DAORegistry;
+use PKP\log\event\PKPSubmissionEventLogEntry;
+use PKP\mail\Mailable;
+use PKP\mail\mailables\ReviewerReinstate;
+use PKP\notification\PKPNotification;
+use PKP\plugins\Hook;
+use PKP\security\Validation;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\submission\reviewRound\ReviewRound;
+
+class ReinstateReviewerForm extends ReviewerNotifyActionForm
+{
+    /**
+     * Constructor
+     *
+     * @param ReviewAssignment $reviewAssignment
+     * @param ReviewRound $reviewRound
+     * @param Submission $submission
+     */
+    public function __construct($reviewAssignment, $reviewRound, $submission)
+    {
+        parent::__construct($reviewAssignment, $reviewRound, $submission, 'controllers/grid/users/reviewer/form/reinstateReviewerForm.tpl');
+    }
+
+    /**
+     * @copydoc ReviewerNotifyActionForm::getMailable()
+     */
+    protected function getMailable(Context $context, Submission $submission, ReviewAssignment $reviewAssignment): Mailable
+    {
+        return new ReviewerReinstate($context, $submission, $reviewAssignment);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     *
+     * @return bool whether or not the review assignment was deleted successfully
+     */
+    public function execute(...$functionArgs)
+    {
+        parent::execute(...$functionArgs);
+
+        $request = Application::get()->getRequest();
+        $submission = $this->getSubmission(); /** @var Submission $submission */
+        $reviewAssignment = $this->getReviewAssignment();
+
+        // Reinstate the review assignment.
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        if (isset($reviewAssignment) && $reviewAssignment->getSubmissionId() == $submission->getId() && !Hook::call('EditorAction::reinstateReview', [&$submission, $reviewAssignment])) {
+            $reviewer = Repo::user()->get($reviewAssignment->getReviewerId());
+            if (!isset($reviewer)) {
+                return false;
+            }
+
+            $reviewAssignment->setCancelled(false);
+            $reviewAssignmentDao->updateObject($reviewAssignment);
+
+            // Stamp the modification date
+            $submission->stampModified();
+            Repo::submission()->dao->update($submission);
+
+            // Insert a trivial notification to indicate the reviewer was reinstated successfully.
+            $currentUser = $request->getUser();
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification($currentUser->getId(), PKPNotification::NOTIFICATION_TYPE_SUCCESS, ['contents' => __('notification.reinstatedReviewer')]);
+
+            // Add log
+            $eventLog = Repo::eventLog()->newDataObject([
+                'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+                'assocId' => $submission->getId(),
+                'eventType' => PKPSubmissionEventLogEntry::SUBMISSION_LOG_REVIEW_REINSTATED,
+                'userId' => Validation::loggedInAs() ?? $currentUser->getId(),
+                'message' => 'log.review.reviewReinstated',
+                'isTranslated' => false,
+                'dateLogged' => Core::getCurrentDate(),
+                'reviewAssignmentId' => $reviewAssignment->getId(),
+                'reviewerName' => $reviewer->getFullName(),
+                'submissionId' => $submission->getId(),
+                'stageId' => $reviewAssignment->getStageId(),
+                'round' => $reviewAssignment->getRound()
+            ]);
+            Repo::eventLog()->add($eventLog);
+
+            return true;
+        }
+        return false;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ResendRequestReviewerForm.php

@@ -0,0 +1,125 @@
+<?php
+/**
+ * @file controllers/grid/users/reviewer/form/ResendRequestReviewerForm.php
+ *
+ * Copyright (c) 2014-2022 Simon Fraser University
+ * Copyright (c) 2003-2022 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ResendRequestReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Allow the editor to resend request to reconsider a declined review assignment invitation
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\core\Request;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use PKP\context\Context;
+use PKP\core\Core;
+use PKP\core\PKPApplication;
+use PKP\db\DAORegistry;
+use PKP\log\event\PKPSubmissionEventLogEntry;
+use PKP\mail\Mailable;
+use PKP\mail\mailables\ReviewerResendRequest;
+use PKP\notification\PKPNotification;
+use PKP\security\Validation;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\submission\reviewRound\ReviewRound;
+
+class ResendRequestReviewerForm extends ReviewerNotifyActionForm
+{
+    /**
+     * Constructor
+     *
+     */
+    public function __construct(ReviewAssignment $reviewAssignment, ReviewRound $reviewRound, Submission $submission)
+    {
+        parent::__construct(
+            $reviewAssignment,
+            $reviewRound,
+            $submission,
+            'controllers/grid/users/reviewer/form/resendRequestReviewerForm.tpl'
+        );
+    }
+
+    protected function getMailable(Context $context, Submission $submission, ReviewAssignment $reviewAssignment): Mailable
+    {
+        return new ReviewerResendRequest($context, $submission, $reviewAssignment);
+    }
+
+    /**
+     * @copydoc ReviewerNotifyActionForm::getEmailKey()
+     */
+    protected function getEmailKey()
+    {
+        return 'REVIEW_RESEND_REQUEST';
+    }
+
+    /**
+     * @copydoc Form::execute()
+     *
+     * @return bool whether or not the review assignment was deleted successfully
+     */
+    public function execute(...$functionArgs)
+    {
+        parent::execute(...$functionArgs);
+
+        $request = Application::get()->getRequest(); /** @var Request $request */
+        $submission = $this->getSubmission(); /** @var Submission $submission */
+        $reviewAssignment = $this->getReviewAssignment(); /** @var ReviewAssignment $reviewAssignment */
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+
+        if (isset($reviewAssignment) && $reviewAssignment->getSubmissionId() == $submission->getId()) {
+            $reviewer = Repo::user()->get($reviewAssignment->getReviewerId());
+            if (!isset($reviewer)) {
+                return false;
+            }
+
+            // $reviewAssignment->setCancelled(false);
+            $reviewAssignment->setDeclined(false);
+            $reviewAssignment->setRequestResent(true);
+            $reviewAssignment->setDateConfirmed(null);
+            $reviewAssignmentDao->updateObject($reviewAssignment);
+
+            // Stamp the modification date
+            $submission->stampLastActivity();
+            Repo::submission()->dao->update($submission);
+
+            // Insert a trivial notification to indicate the reviewer requested to reconsider successfully.
+            $currentUser = $request->getUser();
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification(
+                $currentUser->getId(),
+                PKPNotification::NOTIFICATION_TYPE_SUCCESS,
+                ['contents' => __('notification.reviewerResendRequest')]
+            );
+
+            // Add log
+            $eventLog = Repo::eventLog()->newDataObject([
+                'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+                'assocId' => $submission->getId(),
+                'eventType' => PKPSubmissionEventLogEntry::SUBMISSION_LOG_REVIEW_ASSIGN,
+                'userId' => Validation::loggedInAs() ?? $currentUser->getId(),
+                'message' => 'log.review.reviewerResendRequest',
+                'isTranslated' => false,
+                'dateLogged' => Core::getCurrentDate(),
+                'reviewAssignmentId' => $reviewAssignment->getId(),
+                'reviewerName' => $reviewer->getFullName(),
+                'submissionId' => $submission->getId(),
+                'stageId' => $reviewAssignment->getStageId(),
+                'round' => $reviewAssignment->getRound(),
+            ]);
+            Repo::eventLog()->add($eventLog);
+
+            return true;
+        }
+        return false;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ReviewReminderForm.php

@@ -0,0 +1,188 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/ReviewReminderForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReviewReminderForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for sending a review reminder to a reviewer
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\template\TemplateManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\core\Core;
+use PKP\core\PKPApplication;
+use PKP\db\DAORegistry;
+use PKP\facades\Locale;
+use PKP\form\Form;
+use PKP\log\event\PKPSubmissionEventLogEntry;
+use PKP\mail\mailables\ReviewRemind;
+use PKP\mail\variables\ReviewAssignmentEmailVariable;
+use PKP\notification\PKPNotification;
+use PKP\security\Validation;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use Symfony\Component\Mailer\Exception\TransportException;
+
+class ReviewReminderForm extends Form
+{
+    /** @var ReviewAssignment The review assignment associated with the reviewer */
+    public $_reviewAssignment;
+
+    /**
+     * Constructor.
+     */
+    public function __construct($reviewAssignment)
+    {
+        parent::__construct('controllers/grid/users/reviewer/form/reviewReminderForm.tpl');
+        $this->_reviewAssignment = $reviewAssignment;
+
+        // Validation checks for this form
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    //
+    // Getters and Setters
+    //
+    /**
+     * Get the review assignment
+     *
+     * @return ReviewAssignment
+     */
+    public function getReviewAssignment()
+    {
+        return $this->_reviewAssignment;
+    }
+
+
+    //
+    // Overridden template methods
+    //
+    /**
+     * @copydoc Form::initData
+     */
+    public function initData()
+    {
+        $request = Application::get()->getRequest();
+        $user = $request->getUser();
+        $context = $request->getContext();
+
+        $reviewAssignment = $this->getReviewAssignment();
+        $reviewerId = $reviewAssignment->getReviewerId();
+        $reviewer = Repo::user()->get($reviewerId);
+
+        $submission = Repo::submission()->get($reviewAssignment->getSubmissionId());
+        $mailable = new ReviewRemind($context, $submission, $reviewAssignment);
+        $mailable->sender($user)->recipients([$reviewer]);
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+        $data = $mailable->getData(Locale::getLocale());
+        // Don't expose the reviewer's one-click access URL to editors
+        $data[ReviewAssignmentEmailVariable::REVIEW_ASSIGNMENT_URL] = '{$' . ReviewAssignmentEmailVariable::REVIEW_ASSIGNMENT_URL . '}';
+        $body = Mail::compileParams($template->getLocalizedData('body'), $data);
+
+        $this->setData('stageId', $reviewAssignment->getStageId());
+        $this->setData('reviewAssignmentId', $reviewAssignment->getId());
+        $this->setData('submissionId', $submission->getId());
+        $this->setData('reviewAssignment', $reviewAssignment);
+        $this->setData('reviewerName', $reviewer->getFullName() . ' <' . $reviewer->getEmail() . '>');
+        $this->setData('message', $body);
+        $this->setData('reviewDueDate', $mailable->viewData[ReviewAssignmentEmailVariable::REVIEW_DUE_DATE]);
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign('emailVariables', [
+            'passwordResetUrl' => __('common.url'),
+        ]);
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'message',
+            'reviewDueDate',
+        ]);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionArgs)
+    {
+        $request = Application::get()->getRequest();
+        $reviewAssignment = $this->getReviewAssignment();
+        $reviewerId = $reviewAssignment->getReviewerId();
+        $reviewer = Repo::user()->get($reviewerId);
+        $submission = Repo::submission()->get($reviewAssignment->getSubmissionId());
+        $user = $request->getUser();
+        $context = $request->getContext();
+
+        // Create ReviewRemind email and populate with data
+        $mailable = new ReviewRemind($context, $submission, $reviewAssignment);
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+        $mailable
+            ->subject($template->getLocalizedData('subject'))
+            ->body($this->getData('message'))
+            ->sender($user)
+            ->recipients([$reviewer]);
+
+        // Finally, send email and handle Symfony transport exceptions
+        try {
+            Mail::send($mailable);
+
+            $eventLog = Repo::eventLog()->newDataObject([
+                'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+                'assocId' => $submission->getId(),
+                'eventType' => PKPSubmissionEventLogEntry::SUBMISSION_LOG_REVIEW_REMIND,
+                'userId' => Validation::loggedInAs() ?? $user->getId(),
+                'message' => 'submission.event.reviewer.reviewerReminded',
+                'isTranslate' => 0,
+                'dateLogged' => Core::getCurrentDate(),
+                'recipientId' => $reviewer->getId(),
+                'recipientName' => $reviewer->getFullName(),
+                'senderId' => $user->getId(),
+                'senderName' => $user->getFullName(),
+            ]);
+            Repo::eventLog()->add($eventLog);
+
+            $reviewAssignment->setDateReminded(Core::getCurrentDate());
+            $reviewAssignment->stampModified();
+            $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+            $reviewAssignmentDao->updateObject($reviewAssignment);
+        } catch (TransportException $e) {
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification(
+                $request->getUser()->getId(),
+                PKPNotification::NOTIFICATION_TYPE_ERROR,
+                ['contents' => __('email.compose.error')]
+            );
+            trigger_error($e->getMessage(), E_USER_WARNING);
+        }
+
+        parent::execute(...$functionArgs);
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ReviewerForm.php

@@ -0,0 +1,494 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/ReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Base Form for adding a reviewer to a submission.
+ * N.B. Requires a subclass to implement the "reviewerId" to be added.
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\core\Request;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use PKP\context\Context;
+use PKP\controllers\grid\users\reviewer\PKPReviewerGridHandler;
+use PKP\core\Core;
+use PKP\db\DAORegistry;
+use PKP\facades\Locale;
+use PKP\form\Form;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxAction;
+use PKP\mail\mailables\ReviewRequest;
+use PKP\mail\variables\ReviewAssignmentEmailVariable;
+use PKP\notification\PKPNotification;
+use PKP\reviewForm\ReviewFormDAO;
+use PKP\security\Role;
+use PKP\security\RoleDAO;
+use PKP\submission\action\EditorAction;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\submission\ReviewFilesDAO;
+use PKP\submission\reviewRound\ReviewRound;
+use PKP\submissionFile\SubmissionFile;
+
+class ReviewerForm extends Form
+{
+    /** @var Submission The submission associated with the review assignment */
+    public $_submission;
+
+    /** @var ReviewRound The review round associated with the review assignment */
+    public $_reviewRound;
+
+    /** @var array An array of actions for the other reviewer forms */
+    public $_reviewerFormActions;
+
+    /** @var array An array with all current user roles */
+    public $_userRoles;
+
+    /**
+     * Constructor.
+     *
+     * @param Submission $submission
+     * @param ReviewRound $reviewRound
+     */
+    public function __construct($submission, $reviewRound)
+    {
+        parent::__construct('controllers/grid/users/reviewer/form/defaultReviewerForm.tpl');
+        $this->setSubmission($submission);
+        $this->setReviewRound($reviewRound);
+
+        // Validation checks for this form
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'responseDueDate', 'required', 'editor.review.errorAddingReviewer'));
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'reviewDueDate', 'required', 'editor.review.errorAddingReviewer'));
+
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    //
+    // Getters and Setters
+    //
+    /**
+     * Get the submission Id
+     *
+     * @return int submissionId
+     */
+    public function getSubmissionId()
+    {
+        $submission = $this->getSubmission();
+        return $submission->getId();
+    }
+
+    /**
+     * Get the submission
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->_submission;
+    }
+
+    /**
+     * Get the ReviewRound
+     *
+     * @return ReviewRound
+     */
+    public function getReviewRound()
+    {
+        return $this->_reviewRound;
+    }
+
+    /**
+     * Set the submission
+     *
+     * @param Submission $submission
+     */
+    public function setSubmission($submission)
+    {
+        $this->_submission = $submission;
+    }
+
+    /**
+     * Set the ReviewRound
+     *
+     * @param ReviewRound $reviewRound
+     */
+    public function setReviewRound($reviewRound)
+    {
+        $this->_reviewRound = $reviewRound;
+    }
+
+    /**
+     * Set a reviewer form action
+     *
+     * @param LinkAction $action
+     */
+    public function setReviewerFormAction($action)
+    {
+        $this->_reviewerFormActions[$action->getId()] = $action;
+    }
+
+    /**
+     * Set current user roles.
+     *
+     * @param array $userRoles
+     */
+    public function setUserRoles($userRoles)
+    {
+        $this->_userRoles = $userRoles;
+    }
+
+    /**
+     * Get current user roles.
+     *
+     * @return array $userRoles
+     */
+    public function getUserRoles()
+    {
+        return $this->_userRoles;
+    }
+
+    /**
+     * Get all of the reviewer form actions
+     *
+     * @return array
+     */
+    public function getReviewerFormActions()
+    {
+        return $this->_reviewerFormActions;
+    }
+    //
+    // Overridden template methods
+    //
+    /**
+     * @copydoc Form::initData
+     */
+    public function initData()
+    {
+        $request = Application::get()->getRequest();
+        $context = $request->getContext();
+        $reviewRound = $this->getReviewRound();
+        $submission = $this->getSubmission();
+
+        // Set default review method.
+        $reviewMethod = $context->getData('defaultReviewMode');
+        if (!$reviewMethod) {
+            $reviewMethod = ReviewAssignment::SUBMISSION_REVIEW_METHOD_DOUBLEANONYMOUS;
+        }
+
+        // If there is a section/series and it has a default
+        // review form designated, use it.
+        $sectionId = $submission->getCurrentPublication()->getData(Application::getSectionIdPropName());
+        $section = $sectionId ? Repo::section()->get($sectionId, $context->getId()) : null;
+
+        if ($section) {
+            $reviewFormId = $section->getReviewFormId();
+        } else {
+            $reviewFormId = null;
+        }
+
+        $numWeeks = (int) $context->getData('numWeeksPerReview');
+        if ($numWeeks <= 0) {
+            $numWeeks = 4;
+        }
+        $reviewDueDate = strtotime('+' . $numWeeks . ' week');
+
+        $numWeeks = (int) $context->getData('numWeeksPerResponse');
+        if ($numWeeks <= 0) {
+            $numWeeks = 3;
+        }
+        $responseDueDate = strtotime('+' . $numWeeks . ' week');
+
+        // Get the currently selected reviewer selection type to show the correct tab if we're re-displaying the form
+        $selectionType = (int) $request->getUserVar('selectionType');
+        $stageId = $reviewRound->getStageId();
+
+        $this->setData('submissionId', $this->getSubmissionId());
+        $this->setData('stageId', $stageId);
+        $this->setData('reviewMethod', $reviewMethod);
+        $this->setData('reviewFormId', $reviewFormId);
+        $this->setData('reviewRoundId', $reviewRound->getId());
+        $this->setData('responseDueDate', $responseDueDate);
+        $this->setData('reviewDueDate', $reviewDueDate);
+        $this->setData('selectionType', $selectionType);
+        $this->setData('considered', ReviewAssignment::REVIEW_ASSIGNMENT_NEW);
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $context = $request->getContext();
+
+        // Get the review method options.
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $reviewMethods = $reviewAssignmentDao->getReviewMethodsTranslationKeys();
+
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign('reviewMethods', $reviewMethods);
+        $templateMgr->assign('reviewerActions', $this->getReviewerFormActions());
+
+        $reviewFormDao = DAORegistry::getDAO('ReviewFormDAO'); /** @var ReviewFormDAO $reviewFormDao */
+        $reviewFormsIterator = $reviewFormDao->getActiveByAssocId(Application::getContextAssocType(), $context->getId());
+        $reviewForms = [];
+        while ($reviewForm = $reviewFormsIterator->next()) {
+            $reviewForms[$reviewForm->getId()] = $reviewForm->getLocalizedTitle();
+        }
+
+        $templateMgr->assign('reviewForms', $reviewForms);
+        $templateMgr->assign('emailVariables', [
+            'recipientName' => __('user.name'),
+            'responseDueDate' => __('reviewer.submission.responseDueDate'),
+            'reviewDueDate' => __('reviewer.submission.reviewDueDate'),
+            'reviewAssignmentUrl' => __('common.url'),
+            'recipientUsername' => __('user.username'),
+        ]);
+
+        $templates = $this->getEmailTemplates();
+
+        $templateMgr->assign([
+            'hasCustomTemplates' => (count($templates) > 1),
+            'templates' => $templates,
+        ]);
+
+        // Get the reviewer user groups for the create new reviewer/enroll existing user tabs
+        $reviewRound = $this->getReviewRound();
+        $reviewerUserGroups = Repo::userGroup()->getUserGroupsByStage(
+            $context->getId(),
+            $reviewRound->getStageId(),
+            Role::ROLE_ID_REVIEWER
+        );
+
+        $userGroups = [];
+        foreach ($reviewerUserGroups as $userGroup) {
+            $userGroups[$userGroup->getId()] = $userGroup->getLocalizedName();
+        }
+
+        $this->setData('userGroups', $userGroups);
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'selectionType',
+            'submissionId',
+            'template',
+            'personalMessage',
+            'responseDueDate',
+            'reviewDueDate',
+            'reviewMethod',
+            'skipEmail',
+            'keywords',
+            'interests',
+            'reviewRoundId',
+            'stageId',
+            'selectedFiles',
+            'reviewFormId',
+        ]);
+    }
+
+    /**
+     * Save review assignment
+     */
+    public function execute(...$functionParams)
+    {
+        parent::execute(...$functionParams);
+
+        $submission = $this->getSubmission();
+        $request = Application::get()->getRequest();
+        $context = $request->getContext();
+
+        $currentReviewRound = $this->getReviewRound();
+        $stageId = $currentReviewRound->getStageId();
+        $reviewDueDate = $this->getData('reviewDueDate');
+        $responseDueDate = $this->getData('responseDueDate');
+
+        // Get reviewer id and validate it.
+        $reviewerId = (int) $this->getData('reviewerId');
+
+        if (!$this->_isValidReviewer($context, $submission, $currentReviewRound, $reviewerId)) {
+            fatalError('Invalid reviewer id.');
+        }
+
+        $reviewMethod = (int) $this->getData('reviewMethod');
+
+        $editorAction = new EditorAction();
+        $editorAction->addReviewer($request, $submission, $reviewerId, $currentReviewRound, $reviewDueDate, $responseDueDate, $reviewMethod);
+
+        // Get the reviewAssignment object now that it has been added.
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $reviewAssignment = $reviewAssignmentDao->getReviewAssignment($currentReviewRound->getId(), $reviewerId);
+        $reviewAssignment->setDateNotified(Core::getCurrentDate());
+        $reviewAssignment->stampModified();
+
+        // Ensure that the review form ID is valid, if specified
+        $reviewFormId = (int) $this->getData('reviewFormId');
+        $reviewFormDao = DAORegistry::getDAO('ReviewFormDAO'); /** @var ReviewFormDAO $reviewFormDao */
+        $reviewForm = $reviewFormDao->getById($reviewFormId, Application::getContextAssocType(), $context->getId());
+        $reviewAssignment->setReviewFormId($reviewForm ? $reviewFormId : null);
+
+        $reviewAssignmentDao->updateObject($reviewAssignment);
+
+        $fileStages = [$stageId == WORKFLOW_STAGE_ID_INTERNAL_REVIEW ? SubmissionFile::SUBMISSION_FILE_INTERNAL_REVIEW_FILE : SubmissionFile::SUBMISSION_FILE_REVIEW_FILE];
+        // Grant access for this review to all selected files.
+        $submissionFiles = Repo::submissionFile()
+            ->getCollector()
+            ->filterBySubmissionIds([$submission->getId()])
+            ->filterByReviewRoundIds([$currentReviewRound->getId()])
+            ->filterByFileStages($fileStages)
+            ->getMany();
+
+        $selectedFiles = array_map(function ($id) {
+            return (int) $id;
+        }, (array) $this->getData('selectedFiles'));
+        $reviewFilesDao = DAORegistry::getDAO('ReviewFilesDAO'); /** @var ReviewFilesDAO $reviewFilesDao */
+        foreach ($submissionFiles as $submissionFile) {
+            if (in_array($submissionFile->getId(), $selectedFiles)) {
+                $reviewFilesDao->grant($reviewAssignment->getId(), $submissionFile->getId());
+            }
+        }
+
+        // Insert a trivial notification to indicate the reviewer was added successfully.
+        $reviewer = Repo::user()->get($reviewerId);
+        $currentUser = $request->getUser();
+        $notificationMgr = new NotificationManager();
+        $msgKey = $this->getData('skipEmail') ? 'notification.addedReviewerNoEmail' : 'notification.addedReviewer';
+        $notificationMgr->createTrivialNotification(
+            $currentUser->getId(),
+            PKPNotification::NOTIFICATION_TYPE_SUCCESS,
+            ['contents' => __($msgKey, ['reviewerName' => $reviewer->getFullName()])]
+        );
+
+        return $reviewAssignment;
+    }
+
+
+    //
+    // Protected methods.
+    //
+    /**
+     * Get the link action that fetchs the advanced search form content
+     *
+     * @param Request $request
+     *
+     * @return LinkAction
+     */
+    public function getAdvancedSearchAction($request)
+    {
+        $reviewRound = $this->getReviewRound();
+        return new LinkAction(
+            'addReviewer',
+            new AjaxAction($request->url(null, null, 'reloadReviewerForm', null, [
+                'submissionId' => $this->getSubmissionId(),
+                'stageId' => $reviewRound->getStageId(),
+                'reviewRoundId' => $reviewRound->getId(),
+                'selectionType' => PKPReviewerGridHandler::REVIEWER_SELECT_ADVANCED_SEARCH,
+            ])),
+            __('editor.submission.backToSearch'),
+            'return'
+        );
+    }
+
+
+    //
+    // Private helper methods
+    //
+    /**
+     * Check if a given user id is enrolled in reviewer user group.
+     *
+     * @param Context $context
+     * @param Submission $submission
+     * @param ReviewRound $reviewRound
+     * @param int $reviewerId
+     *
+     * @return bool
+     */
+    public function _isValidReviewer($context, $submission, $reviewRound, $reviewerId)
+    {
+        // Ensure the user isn't already assigned to the current submission
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $reviewAssignments = $reviewAssignmentDao->getBySubmissionId($submission->getId(), $reviewRound->getId());
+        foreach ($reviewAssignments as $reviewAssignment) {
+            if ($reviewerId == $reviewAssignment->getReviewerId()) {
+                return false;
+            }
+        }
+
+        // Ensure that they are a reviewer
+        $roleDao = DAORegistry::getDAO('RoleDAO'); /** @var RoleDAO $roleDao */
+        return $roleDao->userHasRole($context->getId(), $reviewerId, Role::ROLE_ID_REVIEWER);
+    }
+
+    /**
+     * Get the Mailable and populate with data
+     */
+    protected function getMailable(): ReviewRequest
+    {
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $reviewAssignment = $reviewAssignmentDao->newDataObject(); /** @var ReviewAssignment $reviewAssignment */
+        $reviewAssignment->setSubmissionId($this->getSubmissionId());
+        $submission = $this->getSubmission();
+        $request = Application::get()->getRequest();
+        $mailable = new ReviewRequest($request->getContext(), $submission, $reviewAssignment);
+        $mailable->sender($request->getUser());
+        $mailable->addData([
+            'messageToReviewer' => __('reviewer.step1.requestBoilerplate'),
+            'abstractTermIfEnabled' => ($submission->getLocalizedAbstract() == '' ? '' : __('common.abstract')), // Deprecated; for OJS 2.x templates
+        ]);
+
+        // Remove template variables that haven't been set yet during form initialization
+        $mailable->setData(Locale::getLocale());
+        unset($mailable->viewData[ReviewAssignmentEmailVariable::REVIEW_DUE_DATE]);
+        unset($mailable->viewData[ReviewAssignmentEmailVariable::RESPONSE_DUE_DATE]);
+        unset($mailable->viewData[ReviewAssignmentEmailVariable::REVIEW_ASSIGNMENT_URL]);
+
+        return $mailable;
+    }
+
+    /**
+     * Get email templates associated with the form
+     *
+     * @return array [key => name]
+     */
+    protected function getEmailTemplates(): array
+    {
+        $defaultTemplate = Repo::emailTemplate()->getByKey(
+            Application::get()->getRequest()->getContext()->getId(),
+            ReviewRequest::getEmailTemplateKey()
+        );
+        $templateKeys = [ReviewRequest::getEmailTemplateKey() => $defaultTemplate->getLocalizedData('name')];
+
+        $alternateTemplates = Repo::emailTemplate()->getCollector(Application::get()->getRequest()->getContext()->getId())
+            ->alternateTo([ReviewRequest::getEmailTemplateKey()])
+            ->getMany();
+
+        foreach ($alternateTemplates as $alternateTemplate) {
+            $templateKeys[$alternateTemplate->getData('key')] = $alternateTemplate->getLocalizedData('name');
+        }
+
+        return $templateKeys;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ReviewerGossipForm.php

@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/ReviewerGossipForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReviewerGossipForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for viewing and editing gossip about a reviewer
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\facades\Repo;
+use APP\template\TemplateManager;
+use PKP\form\Form;
+use PKP\user\User;
+
+class ReviewerGossipForm extends Form
+{
+    /** @var User The user to gossip about */
+    public $_user;
+
+    /** @var array Arguments used to route the form op */
+    public $_requestArgs;
+
+    /**
+     * Constructor.
+     *
+     * @param User $user The user to gossip about
+     * @param array $requestArgs Arguments used to route the form op to the
+     *  correct submission, stage and review round
+     */
+    public function __construct($user, $requestArgs)
+    {
+        parent::__construct('controllers/grid/users/reviewer/form/reviewerGossipForm.tpl');
+        $this->_user = $user;
+        $this->_requestArgs = $requestArgs;
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    /**
+     * @copydoc Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'gossip',
+        ]);
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign([
+            'requestArgs' => $this->_requestArgs,
+            'gossip' => $this->_user->getGossip(),
+        ]);
+
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionArgs)
+    {
+        $this->_user->setGossip($this->getData('gossip'));
+        Repo::user()->edit($this->_user);
+        parent::execute(...$functionArgs);
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ReviewerNotifyActionForm.php

@@ -0,0 +1,170 @@
+<?php
+/**
+ * @file controllers/grid/users/reviewer/form/ReviewerNotifyActionForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ReviewerNotifyActionForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Perform an action on a review including a reviewer notification email.
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\submission\Submission;
+use Illuminate\Support\Facades\Mail;
+use PKP\context\Context;
+use PKP\form\Form;
+use PKP\mail\Mailable;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewRound\ReviewRound;
+
+abstract class ReviewerNotifyActionForm extends Form
+{
+    /** @var ReviewAssignment The review assignment to alter */
+    public $_reviewAssignment;
+
+    /** @var Submission The submission associated with the review assignment */
+    public $_submission;
+
+    /** @var ReviewRound The review round associated with the review assignment */
+    public $_reviewRound;
+
+    /**
+     * Constructor
+     *
+     * @param ReviewAssignment $reviewAssignment
+     * @param ReviewRound $reviewRound
+     * @param Submission $submission
+     * @param string $template
+     */
+    public function __construct($reviewAssignment, $reviewRound, $submission, $template)
+    {
+        $this->setReviewAssignment($reviewAssignment);
+        $this->setReviewRound($reviewRound);
+        $this->setSubmission($submission);
+
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+
+        parent::__construct($template);
+    }
+
+    abstract protected function getMailable(Context $context, Submission $submission, ReviewAssignment $reviewAssignment): Mailable;
+
+    //
+    // Overridden template methods
+    //
+    /**
+     * @copydoc Form::initData
+     */
+    public function initData()
+    {
+        $request = Application::get()->getRequest();
+        $submission = $this->getSubmission();
+        $reviewAssignment = $this->getReviewAssignment();
+        $reviewRound = $this->getReviewRound();
+        $reviewerId = $reviewAssignment->getReviewerId();
+
+        $this->setData([
+            'submissionId' => $submission->getId(),
+            'stageId' => $reviewRound->getStageId(),
+            'reviewRoundId' => $reviewRound->getId(),
+            'reviewAssignmentId' => $reviewAssignment->getId(),
+            'dateConfirmed' => $reviewAssignment->getDateConfirmed(),
+            'reviewerId' => $reviewerId,
+        ]);
+
+        $context = $request->getContext();
+        $mailable = $this->getMailable($context, $submission, $reviewAssignment);
+        $mailable->sender($request->getUser());
+        $mailable->recipients([Repo::user()->get($reviewerId)]);
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+
+        $this->setData('personalMessage', Mail::compileParams($template->getLocalizedData('body'), $mailable->getData()));
+    }
+
+    /**
+     * @copydoc Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'personalMessage',
+            'reviewAssignmentId',
+            'reviewRoundId',
+            'reviewerId',
+            'skipEmail',
+            'stageId',
+            'submissionId',
+        ]);
+    }
+
+    //
+    // Getters and Setters
+    //
+    /**
+     * Set the ReviewAssignment
+     *
+     * @param mixed $reviewAssignment ReviewAssignment
+     */
+    public function setReviewAssignment($reviewAssignment)
+    {
+        $this->_reviewAssignment = $reviewAssignment;
+    }
+
+    /**
+     * Get the ReviewAssignment
+     *
+     * @return ReviewAssignment
+     */
+    public function getReviewAssignment()
+    {
+        return $this->_reviewAssignment;
+    }
+
+    /**
+     * Set the ReviewRound
+     *
+     * @param mixed $reviewRound ReviewRound
+     */
+    public function setReviewRound($reviewRound)
+    {
+        $this->_reviewRound = $reviewRound;
+    }
+
+    /**
+     * Get the ReviewRound
+     *
+     * @return ReviewRound
+     */
+    public function getReviewRound()
+    {
+        return $this->_reviewRound;
+    }
+
+    /**
+     * Set the submission
+     *
+     * @param Submission $submission
+     */
+    public function setSubmission($submission)
+    {
+        $this->_submission = $submission;
+    }
+
+    /**
+     * Get the submission
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->_submission;
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/ThankReviewerForm.php

@@ -0,0 +1,164 @@
+<?php
+
+/**
+ * @file controllers/grid/users/reviewer/form/ThankReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class ThankReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Form for sending a thank you to a reviewer
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\core\Core;
+use PKP\db\DAORegistry;
+use PKP\facades\Locale;
+use PKP\form\Form;
+use PKP\log\SubmissionEmailLogDAO;
+use PKP\log\SubmissionEmailLogEntry;
+use PKP\mail\mailables\ReviewAcknowledgement;
+use PKP\notification\PKPNotification;
+use PKP\plugins\Hook;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use Symfony\Component\Mailer\Exception\TransportException;
+
+class ThankReviewerForm extends Form
+{
+    /** @var ReviewAssignment The review assignment associated with the reviewer */
+    public $_reviewAssignment;
+
+    /**
+     * Constructor.
+     */
+    public function __construct($reviewAssignment)
+    {
+        parent::__construct('controllers/grid/users/reviewer/form/thankReviewerForm.tpl');
+        $this->_reviewAssignment = $reviewAssignment;
+
+        // Validation checks for this form
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    //
+    // Getters and Setters
+    //
+    /**
+     * Get the review assignment
+     *
+     * @return ReviewAssignment
+     */
+    public function getReviewAssignment()
+    {
+        return $this->_reviewAssignment;
+    }
+
+    //
+    // Overridden template methods
+    //
+    /**
+     * @copydoc Form::initData
+     */
+    public function initData()
+    {
+        $request = Application::get()->getRequest();
+        $user = $request->getUser();
+        $reviewAssignment = $this->getReviewAssignment();
+        $reviewerId = $reviewAssignment->getReviewerId();
+        $reviewer = Repo::user()->get($reviewerId);
+        $submission = Repo::submission()->get($reviewAssignment->getSubmissionId());
+        $contextDao = Application::getContextDAO();
+        $context = $contextDao->getById($submission->getData('contextId'));
+
+        $mailable = new ReviewAcknowledgement($context, $submission, $reviewAssignment);
+        $mailable->sender($user)->recipients([$reviewer]);
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable->getEmailTemplateKey());
+
+        $this->setData('submissionId', $submission->getId());
+        $this->setData('stageId', $reviewAssignment->getStageId());
+        $this->setData('reviewAssignmentId', $reviewAssignment->getId());
+        $this->setData('reviewAssignment', $reviewAssignment);
+        $this->setData('reviewerName', $reviewer->getFullName() . ' <' . $reviewer->getEmail() . '>');
+        $this->setData('message', Mail::compileParams($template->getLocalizedData('body'), $mailable->getData(Locale::getLocale())));
+    }
+
+    /**
+     * Assign form data to user-submitted data.
+     *
+     * @see Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars(['message', 'skipEmail']);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionArgs)
+    {
+        $request = Application::get()->getRequest();
+        $reviewAssignment = $this->getReviewAssignment();
+        $reviewerId = $reviewAssignment->getReviewerId();
+        $reviewer = Repo::user()->get($reviewerId);
+        $submission = Repo::submission()->get($reviewAssignment->getSubmissionId());
+        $contextDao = Application::getContextDAO();
+        $context = $contextDao->getById($submission->getData('contextId'));
+        $user = $request->getUser();
+
+        // Create mailable and populate with data
+        $mailable = new ReviewAcknowledgement($context, $submission, $reviewAssignment);
+        $mailable->sender($user)->recipients([$reviewer]);
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable->getEmailTemplateKey());
+        $mailable->body($this->getData('message'))->subject($template->getLocalizedData('subject'));
+
+        Hook::call('ThankReviewerForm::thankReviewer', [$submission, $reviewAssignment, $mailable]);
+        if (!$this->getData('skipEmail')) {
+            $mailable->setData(Locale::getLocale());
+            try {
+                Mail::send($mailable);
+                $submissionEmailLogDao = DAORegistry::getDAO('SubmissionEmailLogDAO'); /** @var SubmissionEmailLogDAO $submissionEmailLogDao */
+                $submissionEmailLogDao->logMailable(
+                    SubmissionEmailLogEntry::SUBMISSION_EMAIL_REVIEW_THANK_REVIEWER,
+                    $mailable,
+                    $submission,
+                    $user,
+                );
+            } catch (TransportException $e) {
+                $notificationMgr = new NotificationManager();
+                $notificationMgr->createTrivialNotification(
+                    $request->getUser()->getId(),
+                    PKPNotification::NOTIFICATION_TYPE_ERROR,
+                    ['contents' => __('email.compose.error')]
+                );
+                trigger_error($e->getMessage(), E_USER_WARNING);
+            }
+        }
+
+        // update the ReviewAssignment with the acknowledged date
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+        $reviewAssignment->setDateAcknowledged(Core::getCurrentDate());
+        $reviewAssignment->stampModified();
+        if (!in_array($reviewAssignment->getConsidered(), [ReviewAssignment::REVIEW_ASSIGNMENT_CONSIDERED, ReviewAssignment::REVIEW_ASSIGNMENT_RECONSIDERED])) {
+            $reviewAssignment->setConsidered(
+                $reviewAssignment->getConsidered() === ReviewAssignment::REVIEW_ASSIGNMENT_NEW
+                    ? ReviewAssignment::REVIEW_ASSIGNMENT_CONSIDERED
+                    : ReviewAssignment::REVIEW_ASSIGNMENT_RECONSIDERED
+            );
+        }
+        $reviewAssignmentDao->updateObject($reviewAssignment);
+
+        parent::execute(...$functionArgs);
+    }
+}

lib/pkp/controllers/grid/users/reviewer/form/UnassignReviewerForm.php

@@ -0,0 +1,126 @@
+<?php
+/**
+ * @file controllers/grid/users/reviewer/form/UnassignReviewerForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class UnassignReviewerForm
+ *
+ * @ingroup controllers_grid_users_reviewer_form
+ *
+ * @brief Allow the editor to remove a review assignment
+ */
+
+namespace PKP\controllers\grid\users\reviewer\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use PKP\context\Context;
+use PKP\core\Core;
+use PKP\core\PKPApplication;
+use PKP\db\DAORegistry;
+use PKP\log\event\PKPSubmissionEventLogEntry;
+use PKP\mail\Mailable;
+use PKP\mail\mailables\ReviewerUnassign;
+use PKP\notification\NotificationDAO;
+use PKP\notification\PKPNotification;
+use PKP\plugins\Hook;
+use PKP\security\Validation;
+use PKP\submission\reviewAssignment\ReviewAssignment;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+
+class UnassignReviewerForm extends ReviewerNotifyActionForm
+{
+    /**
+     * Constructor
+     *
+     * @param mixed $reviewAssignment ReviewAssignment
+     * @param mixed $reviewRound ReviewRound
+     * @param mixed $submission Submission
+     */
+    public function __construct($reviewAssignment, $reviewRound, $submission)
+    {
+        parent::__construct($reviewAssignment, $reviewRound, $submission, 'controllers/grid/users/reviewer/form/unassignReviewerForm.tpl');
+    }
+
+    /**
+     * @copydoc ReviewerNotifyActionForm::getMailable()
+     */
+    protected function getMailable(Context $context, Submission $submission, ReviewAssignment $reviewAssignment): Mailable
+    {
+        return new ReviewerUnassign($context, $submission, $reviewAssignment);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     *
+     * @return bool whether or not the review assignment was deleted successfully
+     */
+    public function execute(...$functionArgs)
+    {
+        parent::execute(...$functionArgs);
+
+        $request = Application::get()->getRequest();
+        $submission = $this->getSubmission();
+        $reviewAssignment = $this->getReviewAssignment();
+
+        // Delete or cancel the review assignment.
+        $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+
+        if (isset($reviewAssignment) && $reviewAssignment->getSubmissionId() == $submission->getId() && !Hook::call('EditorAction::clearReview', [&$submission, $reviewAssignment])) {
+            $reviewer = Repo::user()->get($reviewAssignment->getReviewerId(), true);
+            if (!isset($reviewer)) {
+                return false;
+            }
+            if ($reviewAssignment->getDateConfirmed()) {
+                // The review has been confirmed but not completed. Flag it as cancelled.
+                $reviewAssignment->setCancelled(true);
+                $reviewAssignmentDao->updateObject($reviewAssignment);
+            } else {
+                // The review had not been confirmed yet. Delete the assignment.
+                $reviewAssignmentDao->deleteById($reviewAssignment->getId());
+            }
+
+            // Stamp the modification date
+            $submission->stampModified();
+            Repo::submission()->dao->update($submission);
+
+            $notificationDao = DAORegistry::getDAO('NotificationDAO'); /** @var NotificationDAO $notificationDao */
+            $notificationDao->deleteByAssoc(
+                Application::ASSOC_TYPE_REVIEW_ASSIGNMENT,
+                $reviewAssignment->getId(),
+                $reviewAssignment->getReviewerId(),
+                PKPNotification::NOTIFICATION_TYPE_REVIEW_ASSIGNMENT
+            );
+
+            // Insert a trivial notification to indicate the reviewer was removed successfully.
+            $currentUser = $request->getUser();
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification($currentUser->getId(), PKPNotification::NOTIFICATION_TYPE_SUCCESS, ['contents' => $reviewAssignment->getDateConfirmed() ? __('notification.cancelledReviewer') : __('notification.removedReviewer')]);
+
+            // Add log
+            $eventLog = Repo::eventLog()->newDataObject([
+                'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+                'assocId' => $submission->getId(),
+                'eventType' => PKPSubmissionEventLogEntry::SUBMISSION_LOG_REVIEW_CLEAR,
+                'userId' => Validation::loggedInAs() ?? $currentUser->getId(),
+                'message' => 'log.review.reviewCleared',
+                'isTranslated' => false,
+                'dateLogged' => Core::getCurrentDate(),
+                'reviewAssignmentId' => $reviewAssignment->getId(),
+                'reviewerName' => $reviewer->getFullName(),
+                'submissionId' => $submission->getId(),
+                'stageId' => $reviewAssignment->getStageId(),
+                'round' => $reviewAssignment->getRound()
+            ]);
+            Repo::eventLog()->add($eventLog);
+
+            return true;
+        }
+        return false;
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/StageParticipantGridCategoryRow.php

@@ -0,0 +1,76 @@
+<?php
+
+/**
+ * @file controllers/grid/users/stageParticipant/StageParticipantGridCategoryRow.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class StageParticipantGridCategoryRow
+ *
+ * @ingroup controllers_grid_users_stageParticipant
+ *
+ * @brief Stage participant grid category row definition
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant;
+
+use APP\submission\Submission;
+use PKP\controllers\grid\GridCategoryRow;
+
+// Link actions
+
+class StageParticipantGridCategoryRow extends GridCategoryRow
+{
+    /** @var Submission */
+    public $_submission;
+
+    /** @var int */
+    public $_stageId;
+
+    /**
+     * Constructor
+     */
+    public function __construct($submission, $stageId)
+    {
+        $this->_submission = $submission;
+        $this->_stageId = $stageId;
+        parent::__construct();
+    }
+
+    //
+    // Overridden methods from GridCategoryRow
+    //
+    /**
+     * @copydoc GridCategoryRow::getCategoryLabel()
+     */
+    public function getCategoryLabel()
+    {
+        $userGroup = $this->getData();
+        return $userGroup->getLocalizedName();
+    }
+
+    //
+    // Private methods
+    //
+    /**
+     * Get the submission for this row (already authorized)
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->_submission;
+    }
+
+    /**
+     * Get the stage ID for this grid.
+     *
+     * @return int
+     */
+    public function getStageId()
+    {
+        return $this->_stageId;
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/StageParticipantGridCellProvider.php

@@ -0,0 +1,49 @@
+<?php
+
+/**
+ * @file controllers/grid/users/stageParticipant/StageParticipantGridCellProvider.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class StageParticipantGridCellProvider
+ *
+ * @ingroup controllers_grid_users_submissionContributor
+ *
+ * @brief Cell provider to retrieve the user's name from the stage assignment
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant;
+
+use APP\facades\Repo;
+use PKP\controllers\grid\DataObjectGridCellProvider;
+use PKP\controllers\grid\GridColumn;
+
+class StageParticipantGridCellProvider extends DataObjectGridCellProvider
+{
+    //
+    // Template methods from GridCellProvider
+    //
+    /**
+     * Extracts variables for a given column from a data element
+     * so that they may be assigned to template before rendering.
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return array
+     */
+    public function getTemplateVarsFromRowColumn($row, $column)
+    {
+        switch ($column->getId()) {
+            case 'participants':
+                $stageAssignment = $row->getData();
+                $user = Repo::user()->get($stageAssignment->getUserId(), true);
+                assert($user);
+                return ['label' => $user ? $user->getFullName() : ''];
+            default:
+                assert(false);
+        }
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/StageParticipantGridHandler.php

@@ -0,0 +1,614 @@
+<?php
+
+/**
+ * @file controllers/grid/users/stageParticipant/StageParticipantGridHandler.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class StageParticipantGridHandler
+ *
+ * @ingroup controllers_grid_users_stageParticipant
+ *
+ * @brief Handle stageParticipant grid requests.
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant;
+
+use APP\core\Application;
+use APP\core\Request;
+use APP\facades\Repo;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use Illuminate\Support\Facades\Mail;
+use PKP\controllers\grid\CategoryGridHandler;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\queries\traits\StageMailable;
+use PKP\controllers\grid\users\stageParticipant\form\AddParticipantForm;
+use PKP\controllers\grid\users\stageParticipant\form\PKPStageParticipantNotifyForm;
+use PKP\core\Core;
+use PKP\core\JSONMessage;
+use PKP\core\PKPApplication;
+use PKP\core\PKPRequest;
+use PKP\db\DAORegistry;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+use PKP\linkAction\request\RedirectAction;
+use PKP\notification\NotificationDAO;
+use PKP\log\event\PKPSubmissionEventLogEntry;
+use PKP\notification\PKPNotification;
+use PKP\security\authorization\WorkflowStageAccessPolicy;
+use PKP\security\Role;
+use PKP\security\Validation;
+use PKP\stageAssignment\StageAssignmentDAO;
+
+class StageParticipantGridHandler extends CategoryGridHandler
+{
+    use StageMailable;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+
+        // Assistants get read-only access
+        $this->addRoleAssignment(
+            [Role::ROLE_ID_ASSISTANT],
+            $peOps = ['fetchGrid', 'fetchCategory', 'fetchRow', 'viewNotify', 'fetchTemplateBody', 'sendNotification']
+        );
+
+        // Managers and Editors additionally get administrative access
+        $this->addRoleAssignment(
+            [Role::ROLE_ID_MANAGER, Role::ROLE_ID_SITE_ADMIN, Role::ROLE_ID_SUB_EDITOR],
+            array_merge($peOps, ['addParticipant', 'deleteParticipant', 'saveParticipant', 'fetchUserList'])
+        );
+        $this->setTitle('editor.submission.stageParticipants');
+    }
+
+
+    //
+    // Getters/Setters
+    //
+    /**
+     * Get the authorized submission.
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->getAuthorizedContextObject(Application::ASSOC_TYPE_SUBMISSION);
+    }
+
+    /**
+     * Get the authorized workflow stage.
+     *
+     * @return int
+     */
+    public function getStageId()
+    {
+        return $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE);
+    }
+
+    //
+    // Overridden methods from PKPHandler
+    //
+    /**
+     * @copydoc PKPHandler::authorize()
+     */
+    public function authorize($request, &$args, $roleAssignments)
+    {
+        $stageId = (int) $request->getUserVar('stageId');
+        $this->addPolicy(new WorkflowStageAccessPolicy($request, $args, $roleAssignments, 'submissionId', $stageId));
+        return parent::authorize($request, $args, $roleAssignments);
+    }
+
+    /**
+     * Determine whether the current user has admin privileges for this
+     * grid.
+     *
+     * @return bool
+     */
+    protected function _canAdminister()
+    {
+        // If the current role set includes Manager or Editor, grant.
+        return (bool) array_intersect(
+            [Role::ROLE_ID_MANAGER, Role::ROLE_ID_SITE_ADMIN, Role::ROLE_ID_SUB_EDITOR],
+            $this->getAuthorizedContextObject(Application::ASSOC_TYPE_USER_ROLES)
+        );
+    }
+
+
+    /**
+     * @copydoc CategoryGridHandler::initialize()
+     *
+     * @param null|mixed $args
+     */
+    public function initialize($request, $args = null)
+    {
+        parent::initialize($request, $args);
+
+        // Columns
+        $cellProvider = new StageParticipantGridCellProvider();
+        $this->addColumn(new GridColumn(
+            'participants',
+            null,
+            null,
+            null,
+            $cellProvider
+        ));
+        $submission = $this->getSubmission();
+        $submissionId = $submission->getId();
+        if (Validation::loggedInAs()) {
+            $router = $request->getRouter();
+            $dispatcher = $router->getDispatcher();
+            $user = $request->getUser();
+            $redirectUrl = $dispatcher->url(
+                $request,
+                PKPApplication::ROUTE_PAGE,
+                null,
+                'workflow',
+                'access',
+                $submissionId
+            );
+            $this->addAction(
+                new LinkAction(
+                    'signOutAsUser',
+                    new RedirectAction(
+                        $dispatcher->url($request, PKPApplication::ROUTE_PAGE, null, 'login', 'signOutAsUser', null, ['redirectUrl' => $redirectUrl])
+                    ),
+                    __('user.logOutAs', ['username' => $user->getUsername()]),
+                    null,
+                    __('user.logOutAs', ['username' => $user->getUsername()])
+                )
+            );
+        }
+
+        // The "Add stage participant" grid action is available to
+        // Editors and Managers only
+        if ($this->_canAdminister()) {
+            $router = $request->getRouter();
+            $this->addAction(
+                new LinkAction(
+                    'requestAccount',
+                    new AjaxModal(
+                        $router->url($request, null, null, 'addParticipant', null, $this->getRequestArgs()),
+                        __('editor.submission.addStageParticipant'),
+                        'modal_add_user'
+                    ),
+                    __('common.assign'),
+                    'add_user'
+                )
+            );
+        }
+
+        $this->setEmptyCategoryRowText('editor.submission.noneAssigned');
+    }
+
+
+    //
+    // Overridden methods from [Category]GridHandler
+    //
+    /**
+     * @copydoc CategoryGridHandler::loadCategoryData()
+     *
+     * @param null|mixed $filter
+     */
+    public function loadCategoryData($request, &$userGroup, $filter = null)
+    {
+        // Retrieve useful objects.
+        $submission = $this->getSubmission();
+        $stageId = $this->getStageId();
+
+        $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+        $stageAssignments = $stageAssignmentDao->getBySubmissionAndStageId(
+            $submission->getId(),
+            $stageId,
+            $userGroup->getId()
+        );
+
+        return $stageAssignments->toAssociativeArray();
+    }
+
+    /**
+     * @copydoc GridHandler::isSubComponent()
+     */
+    public function getIsSubcomponent()
+    {
+        return true;
+    }
+
+    /**
+     * @copydoc GridHandler::getRowInstance()
+     */
+    protected function getRowInstance()
+    {
+        return new StageParticipantGridRow($this->getSubmission(), $this->getStageId(), $this->_canAdminister());
+    }
+
+    /**
+     * @copydoc CategoryGridHandler::getCategoryRowInstance()
+     */
+    protected function getCategoryRowInstance()
+    {
+        $submission = $this->getSubmission();
+        return new StageParticipantGridCategoryRow($submission, $this->getStageId());
+    }
+
+    /**
+     * @copydoc CategoryGridHandler::getCategoryRowIdParameterName()
+     */
+    public function getCategoryRowIdParameterName()
+    {
+        return 'userGroupId';
+    }
+
+    /**
+     * @copydoc GridHandler::getRequestArgs()
+     */
+    public function getRequestArgs()
+    {
+        $submission = $this->getSubmission();
+        return array_merge(
+            parent::getRequestArgs(),
+            [
+                'submissionId' => $submission->getId(),
+                'stageId' => $this->getStageId(),
+            ]
+        );
+    }
+
+    /**
+     * @copydoc GridHandler::loadData()
+     */
+    protected function loadData($request, $filter)
+    {
+        $submission = $this->getSubmission();
+        $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+        $stageAssignments = $stageAssignmentDao->getBySubmissionAndStageId(
+            $this->getSubmission()->getId(),
+            $this->getStageId()
+        );
+
+        // Make a list of the active (non-reviewer) user groups.
+        $userGroupIds = [];
+        while ($stageAssignment = $stageAssignments->next()) {
+            $userGroupIds[] = $stageAssignment->getUserGroupId();
+        }
+
+        // Fetch the desired user groups as objects.
+        $result = [];
+        $userGroups = Repo::userGroup()->getUserGroupsByStage(
+            $request->getContext()->getId(),
+            $this->getStageId()
+        );
+        foreach ($userGroups as $userGroup) {
+            if ($userGroup->getRoleId() == Role::ROLE_ID_REVIEWER) {
+                continue;
+            }
+            if (!in_array($userGroup->getId(), $userGroupIds)) {
+                continue;
+            }
+            $result[$userGroup->getId()] = $userGroup;
+        }
+        return $result;
+    }
+
+
+    //
+    // Public actions
+    //
+    /**
+     * Add a participant to the stages
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function addParticipant($args, $request)
+    {
+        $submission = $this->getSubmission();
+        $stageId = $this->getStageId();
+        $assignmentId = null;
+        if (array_key_exists('assignmentId', $args)) {
+            $assignmentId = $args['assignmentId'];
+        }
+        $userGroups = $this->getGridDataElements($request);
+
+        $form = new AddParticipantForm($submission, $stageId, $assignmentId);
+        $form->initData();
+
+        return new JSONMessage(true, $form->fetch($request));
+    }
+
+    /**
+     * Update the row for the current userGroup's stage participant list.
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function saveParticipant($args, $request)
+    {
+        $submission = $this->getSubmission();
+        $stageId = $this->getStageId();
+        $assignmentId = $args['assignmentId'];
+        $userGroups = $this->getGridDataElements($request);
+
+        $form = new AddParticipantForm($submission, $stageId, $assignmentId);
+        $form->readInputData();
+        if ($form->validate()) {
+            [$userGroupId, $userId, $stageAssignmentId] = $form->execute();
+
+            $notificationMgr = new NotificationManager();
+
+            // Check user group role id.
+            $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+
+            $userGroup = Repo::userGroup()->get($userGroupId);
+            if ($userGroup->getRoleId() == Role::ROLE_ID_MANAGER) {
+                $notificationMgr->updateNotification(
+                    $request,
+                    $notificationMgr->getDecisionStageNotifications(),
+                    null,
+                    Application::ASSOC_TYPE_SUBMISSION,
+                    $submission->getId()
+                );
+            }
+
+            $stages = Application::getApplicationStages();
+            foreach ($stages as $workingStageId) {
+                // remove the 'editor required' task if we now have an editor assigned
+                if ($stageAssignmentDao->editorAssignedToStage($submission->getId(), $workingStageId)) {
+                    $notificationDao = DAORegistry::getDAO('NotificationDAO'); /** @var NotificationDAO $notificationDao */
+                    $notificationDao->deleteByAssoc(Application::ASSOC_TYPE_SUBMISSION, $submission->getId(), null, PKPNotification::NOTIFICATION_TYPE_EDITOR_ASSIGNMENT_REQUIRED);
+                }
+            }
+
+            // Create trivial notification.
+            $user = $request->getUser();
+            if ($stageAssignmentId != $assignmentId) { // New assignment added
+                $notificationMgr->createTrivialNotification($user->getId(), PKPNotification::NOTIFICATION_TYPE_SUCCESS, ['contents' => __('notification.addedStageParticipant')]);
+            } else {
+                $notificationMgr->createTrivialNotification($user->getId(), PKPNotification::NOTIFICATION_TYPE_SUCCESS, ['contents' => __('notification.editStageParticipant')]);
+            }
+
+
+            // Log addition.
+            $assignedUser = Repo::user()->get($userId, true);
+            $eventLog = Repo::eventLog()->newDataObject([
+                'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+                'assocId' => $submission->getId(),
+                'eventType' => PKPSubmissionEventLogEntry::SUBMISSION_LOG_ADD_PARTICIPANT,
+                'userId' => Validation::loggedInAs() ?? $user->getId(),
+                'message' => 'submission.event.participantAdded',
+                'isTranslated' => false,
+                'dateLogged' => Core::getCurrentDate(),
+                'userFullName' => $assignedUser->getFullName(),
+                'username' => $assignedUser->getUsername(),
+                'userGroupName' => $userGroup->getData('name')
+            ]);
+            Repo::eventLog()->add($eventLog);
+
+            return \PKP\db\DAO::getDataChangedEvent($userGroupId);
+        } else {
+            return new JSONMessage(true, $form->fetch($request));
+        }
+    }
+
+    /**
+     * Delete the participant from the user groups
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function deleteParticipant($args, $request)
+    {
+        $submission = $this->getSubmission();
+        $stageId = $this->getStageId();
+        $assignmentId = (int) $request->getUserVar('assignmentId');
+
+        $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+        $stageAssignment = $stageAssignmentDao->getById($assignmentId);
+        if (!$request->checkCSRF() || !$stageAssignment || $stageAssignment->getSubmissionId() != $submission->getId()) {
+            return new JSONMessage(false);
+        }
+
+        // Delete the assignment
+        $stageAssignmentDao->deleteObject($stageAssignment);
+
+        // FIXME: perhaps we can just insert the notification on page load
+        // instead of having it there all the time?
+        $notificationMgr = new NotificationManager();
+        $notificationMgr->updateNotification(
+            $request,
+            $notificationMgr->getDecisionStageNotifications(),
+            null,
+            Application::ASSOC_TYPE_SUBMISSION,
+            $submission->getId()
+        );
+
+        if ($stageId == WORKFLOW_STAGE_ID_EDITING ||
+            $stageId == WORKFLOW_STAGE_ID_PRODUCTION) {
+            // Update submission notifications
+            $notificationMgr->updateNotification(
+                $request,
+                [
+                    PKPNotification::NOTIFICATION_TYPE_ASSIGN_COPYEDITOR,
+                    PKPNotification::NOTIFICATION_TYPE_AWAITING_COPYEDITS,
+                    PKPNotification::NOTIFICATION_TYPE_ASSIGN_PRODUCTIONUSER,
+                    PKPNotification::NOTIFICATION_TYPE_AWAITING_REPRESENTATIONS,
+                ],
+                null,
+                Application::ASSOC_TYPE_SUBMISSION,
+                $submission->getId()
+            );
+        }
+
+        // Log removal.
+        $assignedUser = Repo::user()->get($stageAssignment->getUserId(), true);
+        $userGroup = Repo::userGroup()->get($stageAssignment->getUserGroupId());
+
+        $eventLog = Repo::eventLog()->newDataObject([
+            'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+            'assocId' => $submission->getId(),
+            'eventType' => PKPSubmissionEventLogEntry::SUBMISSION_LOG_REMOVE_PARTICIPANT,
+            'userId' => Validation::loggedInAs() ?? $request->getUser()->getId(),
+            'message' => 'submission.event.participantRemoved',
+            'isTranslated' => false,
+            'dateLogged' => Core::getCurrentDate(),
+            'userFullName' => $assignedUser->getFullName(),
+            'username' => $assignedUser->getUsername(),
+            'userGroupName' => $userGroup->getData('name')
+        ]);
+        Repo::eventLog()->add($eventLog);
+
+        // Redraw the category
+        return \PKP\db\DAO::getDataChangedEvent($stageAssignment->getUserGroupId());
+    }
+
+    /**
+     * Get the list of users for the specified user group
+     *
+     * @param array $args
+     * @param Request $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function fetchUserList($args, $request)
+    {
+        $submission = $this->getSubmission();
+        $stageId = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE);
+
+        $userGroupId = (int) $request->getUserVar('userGroupId');
+
+        $collector = Repo::user()->getCollector();
+        $collector->filterExcludeSubmissionStage($submission->getId(), $stageId, $userGroupId);
+        $users = $collector->getMany();
+
+        $userGroup = Repo::userGroup()->get($userGroupId);
+        $roleId = $userGroup->getRoleId();
+
+        $sectionId = $submission->getSectionId();
+        $contextId = $submission->getContextId();
+
+        $userList = [];
+        foreach ($users as $user) {
+            $userList[$user->getId()] = $user->getFullName();
+        }
+        if (count($userList) == 0) {
+            $userList[0] = __('common.noMatches');
+        }
+
+        return new JSONMessage(true, $userList);
+    }
+
+    /**
+     * Display the notify tab.
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function viewNotify($args, $request)
+    {
+        $this->setupTemplate($request);
+
+        $notifyForm = new PKPStageParticipantNotifyForm($this->getSubmission()->getId(), Application::ASSOC_TYPE_SUBMISSION, $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE));
+        $notifyForm->initData();
+
+        return new JSONMessage(true, $notifyForm->fetch($request));
+    }
+
+    /**
+     * Send a notification from the notify tab.
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function sendNotification($args, $request)
+    {
+        $this->setupTemplate($request);
+
+        $notifyForm = new PKPStageParticipantNotifyForm($this->getSubmission()->getId(), Application::ASSOC_TYPE_SUBMISSION, $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE));
+        $notifyForm->readInputData();
+
+        if ($notifyForm->validate()) {
+            $noteId = $notifyForm->execute();
+
+            if ($this->getStageId() == WORKFLOW_STAGE_ID_EDITING ||
+                $this->getStageId() == WORKFLOW_STAGE_ID_PRODUCTION) {
+                // Update submission notifications
+                $notificationMgr = new NotificationManager();
+                $notificationMgr->updateNotification(
+                    $request,
+                    [
+                        PKPNotification::NOTIFICATION_TYPE_ASSIGN_COPYEDITOR,
+                        PKPNotification::NOTIFICATION_TYPE_AWAITING_COPYEDITS,
+                        PKPNotification::NOTIFICATION_TYPE_ASSIGN_PRODUCTIONUSER,
+                        PKPNotification::NOTIFICATION_TYPE_AWAITING_REPRESENTATIONS,
+                    ],
+                    null,
+                    Application::ASSOC_TYPE_SUBMISSION,
+                    $this->getSubmission()->getId()
+                );
+            }
+
+            $json = new JSONMessage(true);
+            $json->setGlobalEvent('stageStatusUpdated');
+            return $json;
+        } else {
+            // Return a JSON string indicating failure
+            return new JSONMessage(false);
+        }
+    }
+
+    /**
+     * Fetches an email template's message body and returns it via AJAX.
+     *
+     * @param array $args
+     * @param PKPRequest $request
+     *
+     * @return JSONMessage JSON object
+     */
+    public function fetchTemplateBody($args, $request)
+    {
+        $templateKey = $request->getUserVar('template');
+        $context = $request->getContext();
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $templateKey);
+        if ($template) {
+            $submission = $this->getSubmission();
+            $mailable = $this->getStageMailable($context, $submission);
+            $mailable->sender($request->getUser());
+            $data = $mailable->getData();
+
+            $notifyForm = new PKPStageParticipantNotifyForm($submission->getId(), Application::ASSOC_TYPE_SUBMISSION, $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE));
+            return new JSONMessage(
+                true,
+                [
+                    'body' => Mail::compileParams($template->getLocalizedData('body'), $data),
+                    'variables' => $notifyForm->getEmailVariableNames($templateKey),
+                ]
+            );
+        }
+    }
+
+    /**
+     * Get the js handler for this component.
+     *
+     * @return string
+     */
+    public function getJSHandler()
+    {
+        return '$.pkp.controllers.grid.users.stageParticipant.StageParticipantGridHandler';
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/StageParticipantGridRow.php

@@ -0,0 +1,186 @@
+<?php
+
+/**
+ * @file controllers/grid/users/stageParticipant/StageParticipantGridRow.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class StageParticipantGridRow
+ *
+ * @ingroup controllers_grid_users_stageParticipant
+ *
+ * @brief StageParticipant grid row definition
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant;
+
+use APP\facades\Repo;
+use APP\submission\Submission;
+use PKP\controllers\grid\GridRow;
+use PKP\controllers\grid\users\stageParticipant\linkAction\NotifyLinkAction;
+use PKP\core\PKPApplication;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+use PKP\linkAction\request\RedirectConfirmationModal;
+use PKP\linkAction\request\RemoteActionConfirmationModal;
+use PKP\security\Role;
+use PKP\security\Validation;
+
+class StageParticipantGridRow extends GridRow
+{
+    /** @var Submission */
+    public $_submission;
+
+    /** @var int */
+    public $_stageId;
+
+    /** @var bool Whether the user can admin this row */
+    public $_canAdminister;
+
+    /**
+     * Constructor
+     */
+    public function __construct($submission, $stageId, $canAdminister = false)
+    {
+        $this->_submission = $submission;
+        $this->_stageId = $stageId;
+        $this->_canAdminister = $canAdminister;
+
+        parent::__construct();
+    }
+
+
+    //
+    // Overridden methods from GridRow
+    //
+    /**
+     * @copydoc GridRow::initialize()
+     *
+     * @param null|mixed $template
+     */
+    public function initialize($request, $template = null)
+    {
+        // Do the default initialization
+        parent::initialize($request, $template);
+
+        // Is this a new row or an existing row?
+        $rowId = $this->getId();
+        if (!empty($rowId) && is_numeric($rowId)) {
+            // Only add row actions if this is an existing row.
+            $router = $request->getRouter();
+            if ($this->_canAdminister) {
+                $this->addAction(
+                    new LinkAction(
+                        'delete',
+                        new RemoteActionConfirmationModal(
+                            $request->getSession(),
+                            __('editor.submission.removeStageParticipant.description'),
+                            __('editor.submission.removeStageParticipant'),
+                            $router->url($request, null, null, 'deleteParticipant', null, $this->getRequestArgs()),
+                            'modal_delete'
+                        ),
+                        __('grid.action.remove'),
+                        'delete'
+                    )
+                );
+
+                $this->addAction(
+                    new LinkAction(
+                        'requestAccount',
+                        new AjaxModal(
+                            $router->url($request, null, null, 'addParticipant', null, $this->getRequestArgs()),
+                            __('editor.submission.editStageParticipant'),
+                            'modal_edit_user'
+                        ),
+                        __('common.edit'),
+                        'edit_user'
+                    )
+                );
+            }
+
+            $submission = $this->getSubmission();
+            $stageId = $this->getStageId();
+            $stageAssignment = $this->getData();
+            $userId = $stageAssignment->getUserId();
+            $userGroupId = $stageAssignment->getUserGroupId();
+            $context = $request->getContext();
+            $this->addAction(new NotifyLinkAction($request, $submission, $stageId, $userId));
+
+            $user = $request->getUser();
+            if (
+                !Validation::loggedInAs() &&
+                $user->getId() != $userId &&
+                Validation::getAdministrationLevel($userId, $user->getId()) === Validation::ADMINISTRATION_FULL
+            ) {
+                $dispatcher = $router->getDispatcher();
+                $userGroup = Repo::userGroup()->get($userGroupId);
+
+                if ($userGroup->getRoleId() == Role::ROLE_ID_AUTHOR) {
+                    $handler = 'authorDashboard';
+                    $op = 'submission';
+                } else {
+                    $handler = 'workflow';
+                    $op = 'access';
+                }
+                $redirectUrl = $dispatcher->url(
+                    $request,
+                    PKPApplication::ROUTE_PAGE,
+                    $context->getPath(),
+                    $handler,
+                    $op,
+                    $submission->getId()
+                );
+
+                $this->addAction(
+                    new LinkAction(
+                        'logInAs',
+                        new RedirectConfirmationModal(
+                            __('grid.user.confirmLogInAs'),
+                            __('grid.action.logInAs'),
+                            $dispatcher->url($request, PKPApplication::ROUTE_PAGE, null, 'login', 'signInAsUser', $userId, ['redirectUrl' => $redirectUrl])
+                        ),
+                        __('grid.action.logInAs'),
+                        'enroll_user'
+                    )
+                );
+            }
+        }
+    }
+
+    //
+    // Getters/Setters
+    //
+    /**
+     * Get the submission for this row (already authorized)
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->_submission;
+    }
+
+    /**
+     * Get the stage id for this row
+     *
+     * @return int
+     */
+    public function getStageId()
+    {
+        return $this->_stageId;
+    }
+
+    /**
+     * @copydoc GridHandler::getRequestArgs()
+     */
+    public function getRequestArgs()
+    {
+        return [
+            'submissionId' => $this->getSubmission()->getId(),
+            'stageId' => $this->_stageId,
+            'assignmentId' => $this->getId()
+        ];
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/form/AddParticipantForm.php

@@ -0,0 +1,299 @@
+<?php
+
+/**
+ * @file controllers/grid/users/stageParticipant/form/AddParticipantForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class AddParticipantForm
+ *
+ * @ingroup controllers_grid_users_stageParticipant_form
+ *
+ * @brief Form for adding a stage participant
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant\form;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use PKP\db\DAORegistry;
+use PKP\security\Role;
+use PKP\stageAssignment\StageAssignment;
+use PKP\stageAssignment\StageAssignmentDAO;
+use PKP\submission\reviewAssignment\ReviewAssignmentDAO;
+use PKP\userGroup\relationships\UserGroupStage;
+use PKP\userGroup\UserGroup;
+
+class AddParticipantForm extends PKPStageParticipantNotifyForm
+{
+    /** @var Submission The submission associated with the submission contributor being edited */
+    public $_submission;
+
+    /** @var int $_assignmentId Used for edit the assignment */
+    public $_assignmentId;
+
+    /** @var array $_managerGroupIds Contains all manager group_ids  */
+    public $_managerGroupIds;
+
+    /** @var array $_possibleRecommendOnlyUserGroupIds Contains all group_ids that can have the recommendOnly field available for change  */
+    public $_possibleRecommendOnlyUserGroupIds;
+
+    /** @var int $_contextId the current Context Id */
+    public $_contextId;
+
+    /**
+     * Constructor.
+     *
+     * @param Submission $submission
+     * @param int $stageId STAGE_ID_...
+     * @param int $assignmentId Optional - Used for edit the assignment
+     */
+    public function __construct($submission, $stageId, $assignmentId = null)
+    {
+        parent::__construct($submission->getId(), Application::ASSOC_TYPE_SUBMISSION, $stageId, 'controllers/grid/users/stageParticipant/addParticipantForm.tpl');
+        $this->_submission = $submission;
+        $this->_stageId = $stageId;
+        $this->_assignmentId = $assignmentId;
+        $this->_contextId = $submission->getContextId();
+
+        // add checks in addition to anything that the Notification form may apply.
+        // FIXME: should use a custom validator to check that the userId belongs to this group.
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'userGroupId', 'required', 'editor.submission.addStageParticipant.form.userGroupRequired'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+
+        $this->initialize();
+    }
+
+    //
+    // Getters and Setters
+    //
+    /**
+     * Get the Submission
+     *
+     * @return Submission
+     */
+    public function getSubmission()
+    {
+        return $this->_submission;
+    }
+
+    /**
+     * Initialize private attributes that need to be used through all functions.
+     */
+    public function initialize()
+    {
+        // assign all user group IDs with ROLE_ID_MANAGER or ROLE_ID_SUB_EDITOR
+        $this->_managerGroupIds = Repo::userGroup()->getArrayIdByRoleId(Role::ROLE_ID_MANAGER, $this->_contextId);
+        $subEditorGroupIds = Repo::userGroup()->getArrayIdByRoleId(Role::ROLE_ID_SUB_EDITOR, $this->_contextId);
+        $this->_possibleRecommendOnlyUserGroupIds = array_merge($this->_managerGroupIds, $subEditorGroupIds);
+    }
+
+    /**
+     * Determine whether the specified user group is potentially restricted from editing metadata.
+     *
+     * Subeditors can not change their own permissions.
+     */
+    protected function _isChangePermitMetadataAllowed(UserGroup $userGroup, int $userId): bool
+    {
+        $currentUser = Application::get()->getRequest()->getUser();
+
+        if ($currentUser->getId() === $userId && $userGroup->getRoleId() === Role::ROLE_ID_SUB_EDITOR) {
+            return false;
+        }
+
+        return $userGroup->getRoleId() !== Role::ROLE_ID_MANAGER;
+    }
+
+    /**
+     * Determine whether the specified group is potentially required to make recommendations rather than decisions.
+     *
+     * Subeditors can not change their own permissions.
+     */
+    protected function _isChangeRecommendOnlyAllowed(UserGroup $userGroup, int $userId): bool
+    {
+        $currentUser = Application::get()->getRequest()->getUser();
+
+        if ($currentUser->getId() === $userId && $userGroup->getRoleId() === Role::ROLE_ID_SUB_EDITOR) {
+            return false;
+        }
+
+        return in_array($userGroup->getRoleId(), [Role::ROLE_ID_MANAGER, Role::ROLE_ID_SUB_EDITOR]);
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $userGroups = Repo::userGroup()->getUserGroupsByStage(
+            $request->getContext()->getId(),
+            $this->getStageId()
+        );
+
+        $userGroupOptions = [];
+        foreach ($userGroups as $userGroup) {
+            // Exclude reviewers.
+            if ($userGroup->getRoleId() == Role::ROLE_ID_REVIEWER) {
+                continue;
+            }
+            $userGroupOptions[$userGroup->getId()] = $userGroup->getLocalizedName();
+        }
+
+        $templateMgr = TemplateManager::getManager($request);
+        $keys = array_keys($userGroupOptions);
+        $templateMgr->assign([
+            'userGroupOptions' => $userGroupOptions,
+            'selectedUserGroupId' => array_shift($keys), // assign the first element as selected
+            'possibleRecommendOnlyUserGroupIds' => $this->_possibleRecommendOnlyUserGroupIds,
+            'recommendOnlyUserGroupIds' => Repo::userGroup()->getCollector()
+                ->filterByContextIds([$request->getContext()->getId()])
+                ->filterByIsRecommendOnly()
+                ->getMany()
+                ->toArray(),
+            'notPossibleEditSubmissionMetadataPermissionChange' => $this->_managerGroupIds,
+            'permitMetadataEditUserGroupIds' => Repo::userGroup()->getCollector()
+                ->filterByContextIds([$request->getContext()->getId()])
+                ->filterByPermitMetadataEdit(true)
+                ->getMany()
+                ->toArray(),
+            'submissionId' => $this->getSubmission()->getId(),
+            'userGroupId' => '',
+            'userIdSelected' => '',
+        ]);
+
+        if ($this->_assignmentId) {
+            /** @var StageAssignmentDAO $stageAssignmentDao */
+            $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+
+            /** @var StageAssignment $stageAssignment */
+            $stageAssignment = $stageAssignmentDao->getById($this->_assignmentId);
+
+            $currentUser = Repo::user()->get($stageAssignment->getUserId());
+
+            /** @var UserGroup $userGroup */
+            $userGroup = Repo::userGroup()->get($stageAssignment->getUserGroupId());
+
+            $templateMgr->assign([
+                'assignmentId' => $this->_assignmentId,
+                'currentUserName' => $currentUser->getFullName(),
+                'currentUserGroup' => $userGroup->getLocalizedName(),
+                'userGroupId' => $stageAssignment->getUserGroupId(),
+                'userIdSelected' => $stageAssignment->getUserId(),
+                'currentAssignmentRecommendOnly' => $stageAssignment->getRecommendOnly(),
+                'currentAssignmentPermitMetadataEdit' => $stageAssignment->getCanChangeMetadata(),
+                'isChangePermitMetadataAllowed' => $this->_isChangePermitMetadataAllowed($userGroup, $stageAssignment->getUserId()),
+                'isChangeRecommendOnlyAllowed' => $this->_isChangeRecommendOnlyAllowed($userGroup, $stageAssignment->getUserId()),
+            ]);
+        }
+
+
+        // If submission is in review, add a list of reviewer Ids that should not be
+        // assigned as participants because they have anonymous peer reviews in progress
+        $anonymousReviewerIds = [];
+        if (in_array($this->getSubmission()->getStageId(), [WORKFLOW_STAGE_ID_INTERNAL_REVIEW, WORKFLOW_STAGE_ID_EXTERNAL_REVIEW])) {
+            $anonymousReviewMethods = [
+                \PKP\submission\reviewAssignment\ReviewAssignment::SUBMISSION_REVIEW_METHOD_ANONYMOUS,
+                \PKP\submission\reviewAssignment\ReviewAssignment::SUBMISSION_REVIEW_METHOD_DOUBLEANONYMOUS
+            ];
+            $reviewAssignmentDao = DAORegistry::getDAO('ReviewAssignmentDAO'); /** @var ReviewAssignmentDAO $reviewAssignmentDao */
+            $reviewAssignments = $reviewAssignmentDao->getBySubmissionId($this->getSubmission()->getId());
+            $anonymousReviews = array_filter($reviewAssignments, function ($reviewAssignment) use ($anonymousReviewMethods) {
+                return in_array($reviewAssignment->getReviewMethod(), $anonymousReviewMethods) && !$reviewAssignment->getDeclined();
+            });
+            $anonymousReviewerIds = array_map(function ($reviewAssignment) {
+                return $reviewAssignment->getReviewerId();
+            }, $anonymousReviews);
+        }
+        $templateMgr->assign([
+            'anonymousReviewerIds' => array_values(array_unique($anonymousReviewerIds)),
+            'anonymousReviewerWarning' => __('editor.submission.addStageParticipant.form.reviewerWarning'),
+            'anonymousReviewerWarningOk' => __('common.ok'),
+        ]);
+
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * @copydoc Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars([
+            'userGroupId',
+            'userId',
+            'message',
+            'template',
+            'recommendOnly',
+            'canChangeMetadata',
+        ]);
+    }
+
+    /**
+     * @copydoc Form::validate()
+     */
+    public function validate($callHooks = true)
+    {
+        $userGroupId = (int) $this->getData('userGroupId');
+        $userId = (int) $this->getData('userId');
+
+        return Repo::userGroup()->userInGroup($userId, $userGroupId) && Repo::userGroup()->get($userGroupId) && parent::validate($callHooks);
+    }
+
+    /**
+     * @see Form::execute()
+     *
+     * @return array ($userGroupId, $userId)
+     */
+    public function execute(...$functionParams)
+    {
+        $stageAssignmentDao = DAORegistry::getDAO('StageAssignmentDAO'); /** @var StageAssignmentDAO $stageAssignmentDao */
+
+        $submission = $this->getSubmission();
+        $userGroup = Repo::userGroup()->get((int) $this->getData('userGroupId'));
+        $userId = (int) $this->getData('userId');
+        $recommendOnly = $this->_isChangeRecommendOnlyAllowed($userGroup, $userId) ? (bool) $this->getData('recommendOnly') : false;
+        $canChangeMetadata = $this->_isChangePermitMetadataAllowed($userGroup, $userId) ? (bool) $this->getData('canChangeMetadata') : true;
+
+        // sanity check
+        if (UserGroupStage::withStageId($this->getStageId())->withUserGroupId($userGroup->getId())->get()->isNotEmpty()) {
+            $updated = false;
+
+            if ($this->_assignmentId) {
+                /** @var StageAssignment $stageAssignment */
+                $stageAssignment = $stageAssignmentDao->getById($this->_assignmentId);
+
+                if ($stageAssignment) {
+                    $stageAssignment->setRecommendOnly($recommendOnly);
+                    $stageAssignment->setCanChangeMetadata($canChangeMetadata);
+                    $stageAssignmentDao->updateObject($stageAssignment);
+                    $updated = true;
+                }
+            }
+
+            if (!$updated) {
+                // insert the assignment
+                $stageAssignment = $stageAssignmentDao->build($submission->getId(), $userGroup->getId(), $userId, $recommendOnly, $canChangeMetadata);
+            }
+        }
+
+        parent::execute(...$functionParams);
+        return [$userGroup->getId(), $userId, $stageAssignment->getId()];
+    }
+
+    /**
+     * whether or not to require a message field
+     *
+     * @return bool
+     */
+    public function isMessageRequired()
+    {
+        return false;
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/form/PKPStageParticipantNotifyForm.php

@@ -0,0 +1,406 @@
+<?php
+
+/**
+ * @file controllers/grid/users/stageParticipant/form/PKPStageParticipantNotifyForm.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class PKPStageParticipantNotifyForm
+ *
+ * @ingroup controllers_grid_users_stageParticipant_form
+ *
+ * @brief Form to notify a user regarding a file
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant\form;
+
+use APP\core\Application;
+use APP\core\Request;
+use APP\facades\Repo;
+use APP\notification\Notification;
+use APP\notification\NotificationManager;
+use APP\submission\Submission;
+use APP\template\TemplateManager;
+use Illuminate\Support\Facades\Mail;
+use PKP\controllers\grid\queries\traits\StageMailable;
+use PKP\core\Core;
+use PKP\core\PKPApplication;
+use PKP\core\PKPRequest;
+use PKP\db\DAORegistry;
+use PKP\form\Form;
+use PKP\log\event\EventLogEntry;
+use PKP\log\SubmissionEmailLogDAO;
+use PKP\log\SubmissionEmailLogEntry;
+use PKP\note\NoteDAO;
+use PKP\notification\NotificationDAO;
+use PKP\notification\PKPNotification;
+use PKP\query\QueryDAO;
+use PKP\security\Role;
+use PKP\security\Validation;
+use Symfony\Component\Mailer\Exception\TransportException;
+
+class PKPStageParticipantNotifyForm extends Form
+{
+    use StageMailable;
+
+    /** @var int The file/submission ID this form is for */
+    public $_itemId;
+
+    /** @var int The type of item the form is for (used to determine which email template to use) */
+    public $_itemType;
+
+    /** @var int The stage Id */
+    public $_stageId;
+
+    /** @var int the Submission id */
+    public $_submissionId;
+
+    /**
+     * Constructor.
+     *
+     * @param null|mixed $template
+     */
+    public function __construct($itemId, $itemType, $stageId, $template = null)
+    {
+        $template = ($template != null) ? $template : 'controllers/grid/users/stageParticipant/form/notify.tpl';
+        parent::__construct($template);
+        $this->_itemId = $itemId;
+        $this->_itemType = $itemType;
+        $this->_stageId = $stageId;
+
+        if ($itemType == Application::ASSOC_TYPE_SUBMISSION) {
+            $this->_submissionId = $itemId;
+        } else {
+            $submissionFile = Repo::submissionFile()->get($itemId);
+            $this->_submissionId = $submissionFile->getData('submissionId');
+        }
+
+        // Some other forms (e.g. the Add Participant form) subclass this form and
+        // may not enforce the sending of an email.
+        if ($this->isMessageRequired()) {
+            $this->addCheck(new \PKP\form\validation\FormValidator($this, 'message', 'required', 'stageParticipants.notify.warning'));
+        }
+        $this->addCheck(new \PKP\form\validation\FormValidator($this, 'userId', 'required', 'stageParticipants.notify.warning'));
+        $this->addCheck(new \PKP\form\validation\FormValidatorPost($this));
+        $this->addCheck(new \PKP\form\validation\FormValidatorCSRF($this));
+    }
+
+    /**
+     * @copydoc Form::fetch()
+     *
+     * @param null|mixed $template
+     */
+    public function fetch($request, $template = null, $display = false)
+    {
+        $submission = Repo::submission()->get($this->_submissionId);
+        $context = $request->getContext();
+        $user = $request->getUser();
+
+        // Add the templates that can be used for this message
+        if ($user->hasRole([Role::ROLE_ID_MANAGER, Role::ROLE_ID_SUB_EDITOR, Role::ROLE_ID_ASSISTANT], $context->getId())) {
+            $mailable = $this->getStageMailable($context, $submission);
+            $data = $mailable->getData();
+            $defaultTemplate = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+            $templates = [$mailable::getEmailTemplateKey() => $defaultTemplate->getLocalizedData('name')];
+            $alternateTemplates = Repo::emailTemplate()->getCollector($context->getId())
+                ->alternateTo([$mailable::getEmailTemplateKey()])
+                ->getMany();
+            foreach ($alternateTemplates as $alternateTemplate) {
+                $templates[$alternateTemplate->getData('key')] = Mail::compileParams(
+                    $alternateTemplate->getLocalizedData('name'),
+                    $data
+                );
+            }
+        }
+
+        $templateMgr = TemplateManager::getManager($request);
+        $templateMgr->assign([
+            'templates' => $templates,
+            'stageId' => $this->getStageId(),
+            'submissionId' => $this->_submissionId,
+            'itemId' => $this->_itemId,
+        ]);
+
+        if ($request->getUserVar('userId')) {
+            $user = Repo::user()->get($request->getUserVar('userId'));
+            if ($user) {
+                $templateMgr->assign([
+                    'userId' => $user->getId(),
+                    'userFullName' => $user->getFullName(),
+                ]);
+            }
+        }
+
+        return parent::fetch($request, $template, $display);
+    }
+
+    /**
+     * @copydoc Form::readInputData()
+     */
+    public function readInputData()
+    {
+        $this->readUserVars(['message', 'userId', 'template']);
+    }
+
+    /**
+     * @copydoc Form::execute()
+     */
+    public function execute(...$functionParams)
+    {
+        $submission = Repo::submission()->get($this->_submissionId);
+        if ($this->getData('message')) {
+            $request = Application::get()->getRequest();
+            $this->sendMessage((int) $this->getData('userId'), $submission, $request);
+            $this->_logEventAndCreateNotification($request, $submission);
+        }
+        return parent::execute(...$functionParams);
+    }
+
+    /**
+     * Send a message to a user.
+     */
+    public function sendMessage(int $userId, Submission $submission, Request $request)
+    {
+        $user = Repo::user()->get($userId);
+        if (!isset($user)) {
+            return;
+        }
+
+        $contextDao = Application::getContextDAO();
+        $context = $contextDao->getById($submission->getData('contextId'));
+        $mailable = $this->getStageMailable($context, $submission);
+        $templateKey = $this->getData('template');
+        $template = Repo::emailTemplate()->getByKey($context->getId(), $templateKey);
+        if (!$template) {
+            $template = Repo::emailTemplate()->getByKey($context->getId(), $mailable::getEmailTemplateKey());
+        }
+
+        // Create a query
+        $queryDao = DAORegistry::getDAO('QueryDAO'); /** @var QueryDAO $queryDao */
+        $query = $queryDao->newDataObject();
+        $query->setAssocType(PKPApplication::ASSOC_TYPE_SUBMISSION);
+        $query->setAssocId($submission->getId());
+        $query->setStageId($this->_stageId);
+        $query->setSequence(REALLY_BIG_NUMBER);
+        $queryDao->insertObject($query);
+        $queryDao->resequence(PKPApplication::ASSOC_TYPE_SUBMISSION, $submission->getId());
+
+        // Add the current user and message recipient as participants.
+        $queryDao->insertParticipant($query->getId(), $user->getId());
+        if ($user->getId() != $request->getUser()->getId()) {
+            $queryDao->insertParticipant($query->getId(), $request->getUser()->getId());
+        }
+
+        // Create a head note
+        $noteDao = DAORegistry::getDAO('NoteDAO'); /** @var NoteDAO $noteDao */
+        $headNote = $noteDao->newDataObject();
+        $headNote->setUserId($request->getUser()->getId());
+        $headNote->setAssocType(PKPApplication::ASSOC_TYPE_QUERY);
+        $headNote->setAssocId($query->getId());
+        $headNote->setDateCreated(Core::getCurrentDate());
+
+        // Populate mailable with data before compiling headNote title and content
+        $mailable
+            ->addData(['authorName' => $user->getFullName()]) // For compatibility with removed AUTHOR_ASSIGN and AUTHOR_NOTIFY
+            ->sender($request->getUser())
+            ->recipients([$user])
+            ->body($this->getData('message'))
+            ->subject($template->getLocalizedData('subject'));
+
+        // Compile and insert note
+        $headNote->setTitle(Mail::compileParams(
+            $template->getLocalizedData('subject'),
+            $mailable->getData()
+        ));
+        //Substitute email template variables not available before form being executed
+        $additionalVariables = $this->getEmailVariableNames($template->getData('key'));
+        $headNote->setContents(Mail::compileParams(
+            $this->getData('message'),
+            array_intersect_key($mailable->getData(), $additionalVariables)
+        ));
+        $noteDao->insertObject($headNote);
+
+        // Send the email
+        $notificationMgr = new NotificationManager();
+        $notification = $notificationMgr->createNotification(
+            $request,
+            $userId,
+            Notification::NOTIFICATION_TYPE_NEW_QUERY,
+            $request->getContext()->getId(),
+            PKPApplication::ASSOC_TYPE_QUERY,
+            $query->getId(),
+            Notification::NOTIFICATION_LEVEL_TASK
+        );
+
+        $mailable->allowUnsubscribe($notification);
+        $logDao = null;
+        try {
+            Mail::send($mailable);
+            $logDao = DAORegistry::getDAO('SubmissionEmailLogDAO'); /** @var SubmissionEmailLogDAO $logDao */
+        } catch (TransportException $e) {
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createTrivialNotification(
+                $request->getUser()->getId(),
+                PKPNotification::NOTIFICATION_TYPE_ERROR,
+                ['contents' => __('email.compose.error')]
+            );
+            error_log($e->getMessage());
+        }
+
+        // remove the INDEX_ and LAYOUT_ tasks if a user has sent the appropriate _COMPLETE email
+        switch ($templateKey) {
+            case 'EDITOR_ASSIGN':
+                $this->_addAssignmentTaskNotification($request, PKPNotification::NOTIFICATION_TYPE_EDITOR_ASSIGN, $user->getId(), $submission->getId());
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_EDITOR_ASSIGN, $mailable, $submission);
+                break;
+            case 'COPYEDIT_REQUEST':
+                $this->_addAssignmentTaskNotification($request, PKPNotification::NOTIFICATION_TYPE_COPYEDIT_ASSIGNMENT, $user->getId(), $submission->getId());
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_COPYEDIT_NOTIFY_COPYEDITOR, $mailable, $submission);
+                break;
+            case 'LAYOUT_REQUEST':
+                $this->_addAssignmentTaskNotification($request, PKPNotification::NOTIFICATION_TYPE_LAYOUT_ASSIGNMENT, $user->getId(), $submission->getId());
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_LAYOUT_NOTIFY_EDITOR, $mailable, $submission);
+                break;
+            case 'INDEX_REQUEST':
+                $this->_addAssignmentTaskNotification($request, PKPNotification::NOTIFICATION_TYPE_INDEX_ASSIGNMENT, $user->getId(), $submission->getId());
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_INDEX_NOTIFY_INDEXER, $mailable, $submission);
+                break;
+            case 'LAYOUT_COMPLETE':
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_LAYOUT_NOTIFY_COMPLETE, $mailable, $submission);
+                break;
+            case 'INDEX_COMPLETE':
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_INDEX_NOTIFY_COMPLETE, $mailable, $submission);
+                break;
+            default:
+                !$logDao ?: $logDao->logMailable(SubmissionEmailLogEntry::SUBMISSION_EMAIL_DISCUSSION_NOTIFY, $mailable, $submission);
+                break;
+        }
+
+        if ($submission->getStageId() == WORKFLOW_STAGE_ID_EDITING ||
+            $submission->getStageId() == WORKFLOW_STAGE_ID_PRODUCTION) {
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->updateNotification(
+                $request,
+                [
+                    PKPNotification::NOTIFICATION_TYPE_ASSIGN_COPYEDITOR,
+                    PKPNotification::NOTIFICATION_TYPE_AWAITING_COPYEDITS,
+                    PKPNotification::NOTIFICATION_TYPE_ASSIGN_PRODUCTIONUSER,
+                    PKPNotification::NOTIFICATION_TYPE_AWAITING_REPRESENTATIONS,
+                ],
+                null,
+                PKPApplication::ASSOC_TYPE_SUBMISSION,
+                $submission->getId()
+            );
+        }
+    }
+
+    /**
+     * Get the available email template variable names for the given template name.
+     */
+    public function getEmailVariableNames(string $emailKey): array
+    {
+        switch ($emailKey) {
+            case 'COPYEDIT_REQUEST':
+            case 'LAYOUT_REQUEST':
+            case 'INDEX_REQUEST': return [
+                'recipientName' => __('user.name'),
+                'recipientUsername' => __('user.username'),
+                'submissionUrl' => __('common.url'),
+            ];
+            case 'LAYOUT_COMPLETE':
+            case 'INDEX_COMPLETE': return [
+                'recipientName' => __('user.role.editor'),
+            ];
+            case 'EDITOR_ASSIGN_SUBMISSION':
+            case 'EDITOR_ASSIGN_REVIEW':
+            case 'EDITOR_ASSIGN_PRODUCTION':
+            case 'EDITOR_ASSIGN': return [
+                'recipientName' => __('user.name'),
+                'recipientUsername' => __('user.username'),
+                'signature' => __('user.role.editor'),
+                'submissionUrl' => __('common.url'),
+            ];
+        }
+        return [];
+    }
+
+    /**
+     * Get the stage ID
+     *
+     * @return int
+     */
+    public function getStageId()
+    {
+        return $this->_stageId;
+    }
+
+    /**
+     * Add upload task notifications.
+     *
+     * @param PKPRequest $request
+     * @param int $type NOTIFICATION_TYPE_...
+     * @param int $userId User ID
+     * @param int $submissionId Submission ID
+     */
+    private function _addAssignmentTaskNotification($request, $type, $userId, $submissionId)
+    {
+        $notificationDao = DAORegistry::getDAO('NotificationDAO'); /** @var NotificationDAO $notificationDao */
+        $notificationFactory = $notificationDao->getByAssoc(
+            Application::ASSOC_TYPE_SUBMISSION,
+            $submissionId,
+            $userId,
+            $type
+        );
+
+        if (!$notificationFactory->next()) {
+            $context = $request->getContext();
+            $notificationMgr = new NotificationManager();
+            $notificationMgr->createNotification(
+                $request,
+                $userId,
+                $type,
+                $context->getId(),
+                PKPApplication::ASSOC_TYPE_SUBMISSION,
+                $submissionId,
+                Notification::NOTIFICATION_LEVEL_TASK
+            );
+        }
+    }
+
+    /**
+     * Convenience function for logging the message sent event and creating the notification.
+     *
+     * @param PKPRequest $request
+     * @param Submission $submission
+     */
+    public function _logEventAndCreateNotification($request, $submission)
+    {
+        $currentUser = $request->getUser();
+        $eventLog = Repo::eventLog()->newDataObject([
+            'assocType' => PKPApplication::ASSOC_TYPE_SUBMISSION,
+            'assocId' => $submission->getId(),
+            'eventType' => EventLogEntry::SUBMISSION_LOG_MESSAGE_SENT,
+            'userId' => Validation::loggedInAs() ?? $currentUser->getId(),
+            'message' => 'informationCenter.history.messageSent',
+            'isTranslated' => false,
+            'dateLogged' => Core::getCurrentDate()
+        ]);
+        Repo::eventLog()->add($eventLog);
+
+        // Create trivial notification.
+        $notificationMgr = new NotificationManager();
+        $notificationMgr->createTrivialNotification($currentUser->getId(), PKPNotification::NOTIFICATION_TYPE_SUCCESS, ['contents' => __('stageParticipants.history.messageSent')]);
+    }
+
+    /**
+     * whether or not to include the Notify Users listbuilder  true, by default.
+     *
+     * @return bool
+     */
+    public function isMessageRequired()
+    {
+        return true;
+    }
+}

lib/pkp/controllers/grid/users/stageParticipant/linkAction/NotifyLinkAction.php

@@ -0,0 +1,65 @@
+<?php
+/**
+ * @file controllers/grid/users/stageParticipant/linkAction/NotifyLinkAction.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2003-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class NotifyLinkAction
+ *
+ * @ingroup controllers_grid_users_stageParticipant
+ *
+ * @brief An action to open up the notify part of the stage participants grid.
+ */
+
+namespace PKP\controllers\grid\users\stageParticipant\linkAction;
+
+use APP\core\Request;
+use APP\submission\Submission;
+use PKP\linkAction\LinkAction;
+use PKP\linkAction\request\AjaxModal;
+
+class NotifyLinkAction extends LinkAction
+{
+    /**
+     * Constructor
+     *
+     * @param Request $request
+     * @param Submission $submission The submission
+     * @param int $stageId
+     * @param int $userId optional
+     *  to show information about.
+     */
+    public function __construct($request, &$submission, $stageId, $userId = null)
+    {
+        // Prepare request arguments
+        $requestArgs['submissionId'] = $submission->getId();
+        $requestArgs['stageId'] = $stageId;
+        if ($userId) {
+            $requestArgs['userId'] = $userId;
+        }
+
+        $router = $request->getRouter();
+        $ajaxModal = new AjaxModal(
+            $router->url(
+                $request,
+                null,
+                'grid.users.stageParticipant.StageParticipantGridHandler',
+                'viewNotify',
+                null,
+                $requestArgs
+            ),
+            __('submission.stageParticipants.notify'),
+            'modal_email'
+        );
+
+        // Configure the file link action.
+        parent::__construct(
+            'notify',
+            $ajaxModal,
+            __('submission.stageParticipants.notify'),
+            'notify'
+        );
+    }
+}

lib/pkp/controllers/grid/users/userSelect/UserSelectGridCellProvider.php

@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * @file controllers/grid/users/userSelect/UserSelectGridCellProvider.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class UserSelectGridCellProvider
+ *
+ * @ingroup controllers_grid_users_userSelect
+ *
+ * @brief Base class for a cell provider that retrieves data for selecting a user
+ */
+
+namespace PKP\controllers\grid\users\userSelect;
+
+use PKP\controllers\grid\DataObjectGridCellProvider;
+use PKP\controllers\grid\GridColumn;
+
+class UserSelectGridCellProvider extends DataObjectGridCellProvider
+{
+    /** @var int User ID of already-selected user */
+    public $_userId;
+
+    /**
+     * Constructor
+     *
+     * @param int $userId ID of preselected user.
+     */
+    public function __construct($userId = null)
+    {
+        $this->_userId = $userId;
+    }
+
+    //
+    // Template methods from GridCellProvider
+    //
+    /**
+     * Extracts variables for a given column from a data element
+     * so that they may be assigned to template before rendering.
+     *
+     * @param \PKP\controllers\grid\GridRow $row
+     * @param GridColumn $column
+     *
+     * @return array
+     */
+    public function getTemplateVarsFromRowColumn($row, $column)
+    {
+        $element = $row->getData();
+        assert(is_a($element, 'User'));
+        switch ($column->getId()) {
+            case 'select': // Displays the radio option
+                return ['rowId' => $row->getId(), 'userId' => $this->_userId];
+
+            case 'name': // User's name
+                return ['label' => $element->getFullName()];
+        }
+        assert(false);
+    }
+}

lib/pkp/controllers/grid/users/userSelect/UserSelectGridHandler.php

@@ -0,0 +1,244 @@
+<?php
+
+/**
+ * @file controllers/grid/users/userSelect/UserSelectGridHandler.php
+ *
+ * Copyright (c) 2014-2021 Simon Fraser University
+ * Copyright (c) 2000-2021 John Willinsky
+ * Distributed under the GNU GPL v3. For full terms see the file docs/COPYING.
+ *
+ * @class UserSelectGridHandler
+ *
+ * @ingroup controllers_grid_users_userSelect
+ *
+ * @brief Handle user selector grid requests.
+ */
+
+namespace PKP\controllers\grid\users\userSelect;
+
+use APP\core\Application;
+use APP\facades\Repo;
+use PKP\controllers\grid\feature\CollapsibleGridFeature;
+use PKP\controllers\grid\feature\InfiniteScrollingFeature;
+use PKP\controllers\grid\GridColumn;
+use PKP\controllers\grid\GridHandler;
+use PKP\security\authorization\WorkflowStageAccessPolicy;
+use PKP\security\Role;
+
+class UserSelectGridHandler extends GridHandler
+{
+    /** @var array (user group ID => user group name) */
+    public $_userGroupOptions;
+
+    /**
+     * Constructor
+     */
+    public function __construct()
+    {
+        parent::__construct();
+        $this->addRoleAssignment(
+            [Role::ROLE_ID_SUB_EDITOR, Role::ROLE_ID_MANAGER, Role::ROLE_ID_SITE_ADMIN, Role::ROLE_ID_ASSISTANT],
+            ['fetchGrid', 'fetchRows']
+        );
+    }
+
+    //
+    // Implement template methods from PKPHandler
+    //
+    /**
+     * @copydoc PKPHandler::authorize()
+     */
+    public function authorize($request, &$args, $roleAssignments)
+    {
+        $stageId = (int)$request->getUserVar('stageId');
+
+        $this->addPolicy(new WorkflowStageAccessPolicy($request, $args, $roleAssignments, 'submissionId', $stageId));
+
+        return parent::authorize($request, $args, $roleAssignments);
+    }
+
+    /**
+     * @copydoc GridHandler::initialize()
+     *
+     * @param null|mixed $args
+     */
+    public function initialize($request, $args = null)
+    {
+        parent::initialize($request, $args);
+
+        $stageId = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE);
+
+        $userGroups = Repo::userGroup()->getUserGroupsByStage(
+            $request->getContext()->getId(),
+            $stageId
+        );
+
+        $this->_userGroupOptions = [];
+        foreach ($userGroups as $userGroup) {
+            // Exclude reviewers.
+            if ($userGroup->getRoleId() == Role::ROLE_ID_REVIEWER) {
+                continue;
+            }
+            $this->_userGroupOptions[$userGroup->getId()] = $userGroup->getLocalizedName();
+        }
+
+        $this->setTitle('editor.submission.findAndSelectUser');
+
+        // Columns
+        $cellProvider = new UserSelectGridCellProvider();
+        $this->addColumn(
+            new GridColumn(
+                'select',
+                '',
+                null,
+                'controllers/grid/users/userSelect/userSelectRadioButton.tpl',
+                $cellProvider,
+                ['width' => 5]
+            )
+        );
+        $this->addColumn(
+            new GridColumn(
+                'name',
+                'common.name',
+                null,
+                null,
+                $cellProvider,
+                ['alignment' => GridColumn::COLUMN_ALIGNMENT_LEFT,
+                    'width' => 30
+                ]
+            )
+        );
+    }
+
+
+    //
+    // Overridden methods from GridHandler
+    //
+    /**
+     * @copydoc GridHandler::initFeatures()
+     */
+    public function initFeatures($request, $args)
+    {
+        return [new InfiniteScrollingFeature('infiniteScrolling', $this->getItemsNumber()), new CollapsibleGridFeature()];
+    }
+
+    /**
+     * @copydoc GridHandler::loadData()
+     */
+    protected function loadData($request, $filter)
+    {
+        [$filterUserGroupId, $name] = $this->getFilterValues($filter);
+        $submission = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_SUBMISSION);
+        $stageId = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE);
+        $rangeInfo = $this->getGridRangeInfo($request, $this->getId());
+
+        $collector = Repo::user()->getCollector()
+            ->filterByContextIds([$submission->getContextId()])
+            ->filterExcludeSubmissionStage($submission->getId(), $stageId, $filterUserGroupId)
+            ->searchPhrase($name)
+            ->limit($rangeInfo->getCount())
+            ->offset($rangeInfo->getOffset() + max(0, $rangeInfo->getPage() - 1) * $rangeInfo->getCount());
+
+        $users = $collector->getMany()->toArray();
+        $totalCount = $collector->limit(null)->offset(null)->getCount();
+        return new \PKP\core\VirtualArrayIterator($users, $totalCount, $rangeInfo->getPage(), $rangeInfo->getCount());
+    }
+
+    /**
+     * @copydoc GridHandler::renderFilter()
+     */
+    public function renderFilter($request, $filterData = [])
+    {
+        $submission = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_SUBMISSION);
+        $stageId = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE);
+
+        $keys = array_keys($this->_userGroupOptions);
+        $allFilterData = array_merge(
+            $filterData,
+            [
+                'userGroupOptions' => $this->_userGroupOptions,
+                'selectedUserGroupId' => reset($keys),
+                'gridId' => $this->getId(),
+                'submissionId' => $submission->getId(),
+                'stageId' => $stageId,
+            ]
+        );
+        return parent::renderFilter($request, $allFilterData);
+    }
+
+    /**
+     * @copydoc GridHandler::getFilterSelectionData()
+     */
+    public function getFilterSelectionData($request)
+    {
+        $name = (string) $request->getUserVar('name');
+        $filterUserGroupId = (int) $request->getUserVar('filterUserGroupId');
+        return [
+            'name' => $name,
+            'filterUserGroupId' => $filterUserGroupId,
+        ];
+    }
+
+    /**
+     * @copydoc GridHandler::getFilterForm()
+     */
+    protected function getFilterForm()
+    {
+        return 'controllers/grid/users/userSelect/searchUserFilter.tpl';
+    }
+
+    /**
+     * @copydoc GridHandler::getRequestArgs()
+     */
+    public function getRequestArgs()
+    {
+        $submission = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_SUBMISSION);
+        $stageId = $this->getAuthorizedContextObject(Application::ASSOC_TYPE_WORKFLOW_STAGE);
+        return [
+            'submissionId' => $submission->getId(),
+            'stageId' => $stageId,
+        ];
+    }
+
+    /**
+     * Determine whether a filter form should be collapsible.
+     *
+     * @return bool
+     */
+    protected function isFilterFormCollapsible()
+    {
+        return false;
+    }
+
+    /**
+     * Define how many items this grid will start loading.
+     *
+     * @return int
+     */
+    protected function getItemsNumber()
+    {
+        return 20;
+    }
+
+    /**
+     * Process filter values, assigning default ones if
+     * none was set.
+     *
+     * @return array
+     */
+    protected function getFilterValues($filter)
+    {
+        if (isset($filter['filterUserGroupId']) && $filter['filterUserGroupId']) {
+            $filterUserGroupId = $filter['filterUserGroupId'];
+        } else {
+            $keys = array_keys($this->_userGroupOptions);
+            $filterUserGroupId = reset($keys);
+        }
+        if (isset($filter['name']) && $filter['name']) {
+            $name = $filter['name'];
+        } else {
+            $name = null;
+        }
+        return [$filterUserGroupId, $name];
+    }
+}