<?php

echo "[".date("Y-m-d H:i:s")."] GPS members_tracking_trips job is starting.\n";

require('../backend.php');

// We will not limit the SQL we will exhaust the allowed memory
// we will process data in ${hard_limit} batches and hopefully catch up
$hard_limit = 500000;
// GPS coordinate precision to assume the same location
$precision = 3;
// How many seconds is a stop?
$stop_limit = 120;

$httpAuthToken = $savvyext->cfgReadChar('system.oauth2_token');

$db_host = $savvyext->cfgReadChar('database_replica.host');
$db_name = $savvyext->cfgReadChar('database_replica.name');
$db_user = $savvyext->cfgReadChar('database_replica.user');
$db_pass = $savvyext->cfgReadChar('database_replica.pass');
$db_port = $savvyext->cfgReadLong('database_replica.port');
$readOnlyReplicaConnstr = "host=${db_host} port=${db_port} dbname=${db_name} user=${db_user} password=${db_pass}";
$readOnlyReplicaConn = pg_connect($readOnlyReplicaConnstr);

$db_host = $savvyext->cfgReadChar('gpsdatabase.host');
$db_name = $savvyext->cfgReadChar('gpsdatabase.name');
$db_user = $savvyext->cfgReadChar('gpsdatabase.user');
$db_pass = $savvyext->cfgReadChar('gpsdatabase.pass');
$db_port = $savvyext->cfgReadLong('gpsdatabase.port');
$gpsconnstr = "host=${db_host} port=${db_port} dbname=${db_name} user=${db_user} password=${db_pass}";
$gpsconn = pg_connect($gpsconnstr);

$q = "select member_id,count(*) from members_tracking ";
//$q.= "where member_id=55 "; // DEBUG 
$q.= "group by member_id";
$r = pg_query($gpsconn, $q);
if ($r && pg_num_rows($r)) {
    while ($f=pg_fetch_row($r)) {
        $member_id = $f[0];
        echo "[".date("Y-m-d H:i:s")."] Processing member_id=".$member_id." (total member records: ".$f[1].")\n";
        $p = processMemberGPSTrackingTrips($member_id);
        echo "[".date("Y-m-d H:i:s")."] Processed member_id=".$member_id." (processed records: ".$p.")\n";
    }
}

function processMemberGPSTrackingTrips($member_id) {
    global $gpsconn,$precision,$hard_limit,$stop_limit;
    echo "[".date("Y-m-d H:i:s")."] processMemberGPSDataPartition($member_id)\n";
    $id = 0;
    $q = 'select max(location_start),max(location_end) from members_tracking_trips where member_id=' . $member_id;
    $r = pg_query($gpsconn, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        $id = max((int)$f[0],(int)$f[1]);
    }
    echo "[".date("Y-m-d H:i:s")."] Last processed ID is ${id}\n";

    $q = "select a.first_id,a.last_id,a.device_id,extract(milliseconds from a.duration) as ms, ";
    $q.= "extract(epoch from a.duration) as seconds, c.speed, a.inner_duration, a.total, ";
    $q.= "ST_Distance(c.gps,b.gps) AS distance, b.gps AS gps_start, c.gps AS gps_end,";
    $q.= "EXTRACT(epoch FROM c.ttime-b.ttime) AS travel_time ";
    $q.= "from members_tracking_duration a ";
    $q.= "left join members_tracking b on (b.id=a.first_id) ";
    $q.= "left join members_tracking c on (c.id=a.last_id) ";    
    $q.= "where a.member_id=${member_id} ";
    $q.= "and a.first_id>${id} AND a.last_id>${id} "; // Limit ?
    $q.= "order by a.device_id, a.first_time limit ${hard_limit}";
    //echo "\n$q\n";
    $r = pg_query($gpsconn, $q);
    
    if ($r && pg_num_rows($r)) {
        echo "[".date("Y-m-d H:i:s")."] Records to process: ".pg_num_rows($r)."\n";
    } else {
        echo "[".date("Y-m-d H:i:s")."] No new records to process. Stop.\n";
        return 0;
    }
    
    echo "[".date("Y-m-d H:i:s")."] Processing";

    $trip = [];
    $trips = [];
    $trip_data = ['distance'=>0,'duration'=>0,'total'=>0,'speed'=>0];
    $trips_data = []; 
    $processed = 0;
    $last_device_id = -1;
    $r = pg_query($gpsconn, $q);
    while ($f=pg_fetch_assoc($r)) {
        //$res[] = $f;
        //if ($f["seconds"]>=$stop_limit || ($last_device_id!=$f["device_id"] && count($trip)>0)) {
        if ($f["inner_duration"]>=$stop_limit || ($last_device_id!=$f["device_id"] && count($trip)>0)) {
            $trips[] = $trip;
            $trips_data[] = $trip_data;
            $n = count($trip)-1;
            list ($res, $err) = processMemberGPSTrackingTripsSave(
                $member_id,
                $trip[0],
                array_pop($trip),
                $trip_data);
            if ($res && $res["id"]>0) {
                echo "[".date("Y-m-d H:i:s")."] New trip processed: ".$res["id"]." (member_id=${member_id})\n";
            } else {
                echo "[".date("Y-m-d H:i:s")."] Failed to process trip: ${err} (member_id=${member_id})\n";
                var_dump($trip_data); // DEBUG
            }
            unset($trip);
            unset($trip_data);
            $trip = [];
            $trip_data = ['distance'=>0,'duration'=>0,'total'=>0,'speed'=>0];
        } else {
            $trip[] = $f;
            $trip_data['distance'] += $f["distance"];
            $trip_data['duration'] += $f["ms"];
            $trip_data['speed'] += $f["ms"]>0 ? (3600 * $f["distance"] / $f["ms"]) : 0; // km/h
            $trip_data['total'] += 1;
        }
        $last_device_id = $f["device_id"];
        $processed++;        
    }
    pg_free_result($r);
    return $processed;
}

function processMemberGPSTrackingTripsSave($member_id,$first,$last,$trip_data) {
    global $gpsconn;

    $distance  = $trip_data['distance'];
    $duration  = $trip_data['duration']/1000;

    if ($distance>0 && $duration>0) {
        // OK
    } else {
        return [NULL, "Distance and/or duration are invalid!"];
    }

    $speed     = 3600 * $trip_data['distance'] / $trip_data['duration'];
    $avg_speed = $trip_data['speed'] / $trip_data['total'];
    $device_id = ($first['device_id']>0 ? $first['device_id'] : "NULL");
    
    $location_start = $first['last_id'];
    $location_end   = $last['last_id'];
    $gps_start = $first['gps_end'];
    $gps_end   = $last['gps_end'];

    $address_start = processMemberGPSTrackingTripsReverseGeocode($gps_start);
    $address_end = processMemberGPSTrackingTripsReverseGeocode($gps_end);

    $q = "SELECT * FROM members_tracking_trips WHERE member_id=${member_id} ";
    $q.= "AND location_start=${location_start} AND location_end=${location_end} ";
    $q.= "AND ".($device_id=="NULL"?"device_id IS NULL":"device_id=${device_id}");
    $r = pg_query($gpsconn, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_assoc($r)) {
        $q = "UPDATE members_tracking_trips SET distance=${distance},duration=${duration},";
        $q.= "speed=${speed},avg_speed=${avg_speed},gps_start='${gps_start}',gps_end='${gps_end}',";
        $q.= "address_start='${address_start}',address_end='${address_end}' WHERE member_id=${member_id} ";
        $q.= "AND location_start=${location_start} AND location_end=${location_end} ";
        $q.= "AND ".($device_id=="NULL"?"device_id IS NULL":"device_id=${device_id}");
        $q.=" RETURNING *";
    } else {
        $q = "INSERT INTO members_tracking_trips (member_id,distance,duration,speed,avg_speed,location_start,location_end,device_id,gps_start,gps_end,address_start,address_end) VALUES(";
        $q.= "${member_id},${distance},${duration},${speed},${avg_speed},${location_start},${location_end},${device_id},'${gps_start}','${gps_end}',${address_start},${address_end}";
        $q.= ") RETURNING *";
    }
    $r = pg_query($gpsconn, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_assoc($r)) {
        pg_free_result($r);
        return [$f, NULL];
    }
    echo "\n$q\n";
    return [NULL, pg_last_error($gpsconn)];
}

function processMemberGPSTrackingTripsReverseGeocode($gps) {
    global $gpsconn, $readOnlyReplicaConn;
    if ($gps==NULL || $gps=="") {
        echo "[".date("Y-m-d H:i:s")."] Empty GPS string\n";
        return "NULL";
    }
    $q = "SELECT ST_Y('${gps}') AS lat, ST_X('${gps}') AS lng";
    $r = pg_query($gpsconn, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        $lat = $f[0];
        $lng = $f[1];
    } else {
        echo "[".date("Y-m-d H:i:s")."] Failed to decode GPS: '${gps}'\n";
        return "NULL";
    }
    list ($address,$err) = reverseGeocode($readOnlyReplicaConn, $lat, $lng);
    if (!$address && $err) {
        echo "[".date("Y-m-d H:i:s")."] Failed to reverse geocode GPS: ${lat},${lng}\n";
        return "NULL";
    }
    $q = "SELECT id FROM address WHERE lower(address)=lower('".pg_escape_string($address)."') ORDER BY geocoding_date DESC LIMIT 1";
    //echo "\n\n${q}\n\n";
    $r = pg_query($readOnlyReplicaConn, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        return $f[0];
    }
    echo "[".date("Y-m-d H:i:s")."] Failed to load address: '${address}'\n";
    return "NULL";
}

function reverseGeocode($db, $lat, $lng) {
    // Reverse geocode using local DB
    list($res,$err) = GeocodeReverseGeocode($db, $lat, $lng);
    if (is_array($res) && isset($res["address"])) {
        return [$res["address"],NULL];
    }
    // Reverse geocode service using Google Maps API
    list($res,$err) = reverseGeocodeService($db, $lat, $lng);
    if (is_array($res) && isset($res["address"]) && $res["address"]!="") {
        reverseGeocodeServiceSave($db, $res);
        return [$res["address"],NULL];
    }
    return [NULL, $err];
}

function GeocodeReverseGeocode($db, $lat, $lng) {
    $db_lat = ((float)$lat);
    $db_lng = ((float)$lng);
    // Check our local address table with precisions 5 to 3
    for ($i=5;$i>2;$i--) {
        $q = "SELECT * FROM address WHERE round(latitude,${i})=round(${db_lat},${i}) AND round(longitude,${i})=round(${db_lng},${i})";
        $r = pg_query($db, $q);
        if ($r && pg_num_rows($r) && $f=pg_fetch_assoc($r)) {
            return [$f, NULL];
        }
    }
    // Check our local Singapore table with precisions 5 to 3
    /* for ($i=5;$i>2;$i--) {
        $q = "SELECT * FROM singapore_buildings WHERE round(latitude,${i})=round(${db_lat},${i}) AND round(longitude,${i})=round(${db_lng},${i})";
        $r = pg_query($q);
        if ($r && pg_num_rows($r) && $f=pg_fetch_assoc($r)) {
            return [$f, NULL];
        }
    } //*/
    return [NULL, pg_last_error($db)];
}

function reverseGeocodeServiceSave($db, $result) {
    $db_lat = floatval($result["lat"]);
    $db_lng = floatval($result["lng"]);
    $db_address = pg_escape_string($result["address"]);
    $db_postal = pg_escape_string($result["postal"]);
    $db_tz = GeocodeGetTimezone($db, $result["timeZoneId"]);
    // Check the address exists
    $q = "SELECT id FROM address WHERE lower(address)=lower('${db_address}') ";
    $q.= "AND latitude<>0 AND longitude<>0 AND geocoding_date IS NOT NULL ";
    $q.= "ORDER BY geocoding_date DESC LIMIT 1";
    //error_log($q);
    $r = pg_query($db, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        return $f[0];
    }
    $q = "INSERT INTO address (address,latitude,longitude,timezone,geocoding_date,postal) VALUES (";
    $q.= "'${db_address}',${db_lat},${db_lng},".($db_tz==NULL?"NULL":$db_tz).",now(),'${db_postal}')";
    $q.= " RETURNING id";
    $r = pg_query($db, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        return $f[0];
    }
    return NULL;
}

function GeocodeGetTimezone($db, $timezone) {
    $db_timezone = pg_escape_string($timezone);
    $q = "SELECT id FROM address_timezone WHERE timezone='${db_timezone}'";
    $r = pg_query($db, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        return $f[0];
    }
    $q = "INSERT INTO address_timezone (timezone) VALUES('${db_timezone}') RETURNING id";
    $r = pg_query($db, $q);
    if ($r && pg_num_rows($r) && $f=pg_fetch_row($r)) {
        return $f[0];
    }
    return NULL;
}

function reverseGeocodeService($db, $lat, $lng) {
    global $httpAuthToken;
    $data = http_build_query(
        array(
            'lat' => $lat,
            'lng' => $lng
        )
    );
    $url = "http://oauth2.service/api/v1/reverse?" . $data;
    //echo "\n\n${url}\n\n";
    $opts = array(
        'http' => array(
            'method' => "GET",
            'timeout' => 60, /* 1 minute */
            'header'  => 
                "Content-Type: application/x-www-form-urlencoded\r\n" .
                "Accept: application/json\r\n" .
                "Authorization: Server-Token ${httpAuthToken}\r\n",
        )
    );
    $context = stream_context_create($opts);
    $body = file_get_contents($url, false, $context);
    //error_log("BODY: ".$body);
    $geocoded = json_decode($body,true);
    if (is_array($geocoded) && is_array($geocoded["data"]) && !isset($geocoded["error"])) {
        //error_log(json_encode($geocoded));
        // Cache the result in DB
        /*Geocode::saveDistanceCache(
            $db->getConnect(), $fromLat, $fromLng, $toLat, $toLng, $geocoded["data"]);
        */
        return [$geocoded["data"], NULL];
    } else if (is_array($geocoded) && isset($geocoded["error"])) {
        $body = $geocoded["error"];
    }
    return [NULL, "Reverse geocoding service call error: ".$body];        
}

pg_close($readOnlyReplicaConn);
pg_close($gpsconn);
echo "[".date("Y-m-d H:i:s")."] GPS members_tracking_trips job complete.\n";