Reworked the fee calculations structure

app/api/services/base_service.py

@@ -79,11 +79,11 @@ class BaseService:
             return {"error": "No charges found for the offer"}
 
         loan_charges = offer.charges
-        tenor = offer.tenor // 30 # Convert to months
-        interest = cls.get_charge_detail(charges = loan_charges, code = "INTEREST", amount = amount)
-        management = cls.get_charge_detail(charges = loan_charges, code = "MGTFEE", amount = amount)
-        insurance = cls.get_charge_detail(charges = loan_charges, code = "INSURANCE", amount = amount)
-        vat = cls.get_charge_detail(charges = loan_charges, code = "VAT", amount = amount, management_fee = management["fee"])
+        tenor = offer.schedule # offer.tenor // 30 # Convert to months
+        interest =  cls.get_charge_detail(rates = offer.interest_rate, charges = loan_charges, code = "INTEREST", amount = amount)
+        management = cls.get_charge_detail(rates = offer.management_rate,  charges = loan_charges, code = "MGTFEE", amount = amount)
+        insurance = cls.get_charge_detail(rates = offer.insurance_rate, charges = loan_charges, code = "INSURANCE", amount = amount)
+        vat = cls.get_charge_detail(rates = offer.vat_rate, charges = loan_charges, code = "VAT", amount = amount, management_fee = management["fee"])
 
         # Separate fees into upfront and postpaid
         upfront_fees = [
@@ -97,18 +97,29 @@ class BaseService:
             for fee in [interest, management, insurance, vat]
             if fee["due_days"] != 0
         ]
+        vat_test  = vat["fee"]
+        logger.info(f"VAT fee ==  *************** : {vat_test}")
 
         # Up-front payment: (only those fees due immediately i.e due_days == 0)
-        upfront_payment = sum(upfront_fees)
+        # upfront_payment = sum(upfront_fees)
+        if offer.schedule == 1:
+            upfront_payment = vat["fee"] + management["fee"] + insurance["fee"] + interest["fee"]
+            interest_amount = interest["fee"]
+            repayment_amount = amount
+        else:
+            upfront_payment = vat["fee"] + insurance["fee"]+management["fee"]
+            interest_amount = interest["fee"]*offer.schedule
+            repayment_amount = amount +  interest_amount
 
-          # Repayment amount: (principal + only those fees not due immediately i.e due_days != 0)
-        repayment_amount = amount + (sum(postpaid_fees) * tenor)
+
+        # Repayment amount: (principal + only those fees not due immediately i.e due_days != 0)
+       # repayment_amount = amount + (sum(postpaid_fees) * tenor)
 
         # Total amount: (upfront_payment + repayment_amount)
         total_amount = upfront_payment + repayment_amount
 
         # Calculate the installment amount
-        installment_amount = repayment_amount / tenor
+        installment_amount = repayment_amount / offer.schedule
 
         return {
             "interest": interest,
@@ -123,28 +134,39 @@ class BaseService:
 
     
     @classmethod
-    def get_charge_detail(cls, charges, code, amount, management_fee=None):
+    def get_charge_detail(cls, rates, charges, code, amount, management_fee= 0.0):
         """
         Get details for a specific charge code from a list of loan charges.
 
         Returns default values if not found.
         """
+        fee = 0.0
 
-        
-        for charge in charges:
-            if charge.code == code:
-                fee = (
-                    management_fee * charge.percent / 100
-                    if code == "VAT" and management_fee is not None
-                    else amount * charge.percent / 100
-                )
+        if code == "VAT" and management_fee > 0:
+            fee = management_fee * rates / 100
+        else:
+            fee = amount * rates / 100
+
+        return {
+            "rate": rates,
+            "fee": round(fee, 2),
+            "due_days": 30,
+            "code": code,
+            "description" :  "have no idea how to get this yet"
+        }
+
+        # if charge.code == code:
+        #     if code == "VAT" and management_fee > 0:
+        #         fee = management_fee * rates / 100
+        #     else:
+        #         fee = amount * rates / 100
+        #
+        #     return {
+        #         "rate": rates,
+        #         "fee": round(fee, 2),
+        #         "due_days": charge.due
+        #     }
             
-                return {
-                    "rate": charge.percent,
-                    "fee": round(fee, 2),
-                    "due_days": charge.due
-                }
-            
-        return {"rate": 0, "fee": 0, "due_days": 0}
+       # return {"rate": 0, "fee": 0, "due_days": 0}
 
 

app/api/services/provide_loan.py

@@ -11,6 +11,10 @@ from threading import Thread
 from app.models import Loan, Offer, Charge
 from app.api.enums import LoanStatus
 from app.extensions import db
+from datetime import datetime, timezone
+from dateutil.relativedelta import relativedelta
+from app.models import LoanRepaymentSchedule 
+
 
 class ProvideLoanService(BaseService):
     TRANSACTION_TYPE = TransactionType.PROVIDE_LOAN 
@@ -66,7 +70,16 @@ class ProvideLoanService(BaseService):
                     charges = ProvideLoanService.calculate_charges(offer, amount)
                     upfront_fee = charges["upfront_payment"]
                     repayment_amount = charges["repayment_amount"]
+                    #installment_amount = charges["installment_amount"]
+                    tenor = offer.tenor // 30 # Convert to months
+
+                    upfront_payment = charges["upfront_payment"]
+                    total_amount = charges["total_amount"]
                     installment_amount = charges["installment_amount"]
+                    interest = charges["interest"]
+                    management = charges["management"]
+                    insurance = charges["insurance"]
+                    vat = charges["vat"]
                     
 
 
@@ -85,17 +98,24 @@ class ProvideLoanService(BaseService):
                         status= LoanStatus.ACTIVE
                     )
 
-                    db.session.flush()
-
-
                     if not loan:
                         logger.error(f"Failed to save loan details")
                         return jsonify({
                             "message": "Failed to save loan details."
                         }), 400
-                    
-            
-                    charges = Charge.get_offer_charges(offer.id)
+
+                    db.session.flush()
+
+                    schedule = LoanRepaymentSchedule.add_repayment_schedule(loan = loan, tenor = tenor)
+
+
+                    if not schedule:
+                        logger.error(f"Failed to create repayment schedule for loan ID {loan.id}")
+                        return jsonify({
+                            "message": "Failed to generate loan repayment schedule."
+                        }), 400
+
+                    # charges = Charge.get_offer_charges(offer.id)
 
                     logger.error(f"{charges}")
                     
@@ -152,8 +172,4 @@ class ProvideLoanService(BaseService):
             db.session.rollback() 
             return jsonify({
                 "message": "Internal Server Error"
-                }) , 500
-        
-    
- 
-
+                }) , 500

app/api/services/select_offer.py

@@ -61,6 +61,7 @@ class SelectOfferService(BaseService):
                 management = charges["management"]
                 insurance = charges["insurance"]
                 vat = charges["vat"]
+                repayment_amount = charges["repayment_amount"]
 
 
                 # Calculate the repayment dates
@@ -68,7 +69,7 @@ class SelectOfferService(BaseService):
                 start_date = date.today()
 
                 # Convert tenor to months
-                months = tenor  // 30
+                months = offer.schedule # tenor  // 30
 
                 recommended_repayment_dates = [
                     (start_date + relativedelta(months=i + 1)).isoformat()
@@ -83,19 +84,35 @@ class SelectOfferService(BaseService):
                         "productId": product_id,
                         "amount": amount,
                         "upfrontPayment": upfront_payment,
-                        "interestRate": interest["rate"],
-                        "managementRate": management["rate"],
+                        "interestRate": offer.interest_rate,
+                        "managementRate": offer.management_rate,
                         "managementFee": management["fee"],
-                        "insuranceRate": insurance["rate"],
+                        "insuranceRate": offer.insurance_rate,
                         "insuranceFee": insurance["fee"],
-                        "VATRate": vat["rate"],
+                        "VATRate": offer.vat_rate,
                         "VATAmount": vat["fee"],
                         "recommendedRepaymentDates": recommended_repayment_dates,
+                        "repaymentAmount": repayment_amount,
                         "installmentAmount": installment_amount,
                         "totalRepaymentAmount": total_amount,
                     }
                 ]
 
+                # "offerId": offer.id,
+                # "productId": product_id,
+                # "amount": amount,
+                # "upfrontPayment": upfront_payment,
+                # "interestRate": interest["rate"],
+                # "managementRate": management["rate"],
+                # "managementFee": management["fee"],
+                # "insuranceRate": insurance["rate"],
+                # "insuranceFee": insurance["fee"],
+                # "VATRate": vat["rate"],
+                # "VATAmount": vat["fee"],
+                # "recommendedRepaymentDates": recommended_repayment_dates,
+                # "installmentAmount": installment_amount,
+                # "totalRepaymentAmount": total_amount,
+                #
                 # Business logic - selecting an offer
                 response_data = {
                     "outstandingDebtAmount": 0,

app/models/__init__.py

@@ -7,6 +7,7 @@ from .loan_charge import LoanCharge
 from .offer import Offer
 from .charge import Charge
 from .rac_checks import RACCheck
+from .loan_repayment_schedule import LoanRepaymentSchedule
 
 
-__all__ = ['Customer', 'Account', 'Loan', 'Transaction', 'Repayment', 'LoanCharge', 'Offer', 'Charge', 'RACCheck']
+__all__ = ['Customer', 'Account', 'Loan', 'Transaction', 'Repayment', 'LoanCharge', 'Offer', 'Charge', 'RACCheck', 'LoanRepaymentSchedule']

app/models/loan.py

@@ -4,7 +4,7 @@ from app.models.customer import Customer
 from app.models.account import Account
 from sqlalchemy.exc import IntegrityError
 from sqlalchemy.orm import relationship
-from app.models.loan_charge import LoanCharge
+from dateutil.relativedelta import relativedelta 
 
 
 class Loan(db.Model):
@@ -42,11 +42,19 @@ class Loan(db.Model):
 
     loan_charges = relationship(
         "LoanCharge",
-        primaryjoin="Loan.id == LoanCharge.loan_id",
+        primaryjoin="LoanCharge.loan_id == Loan.id",
         foreign_keys="LoanCharge.loan_id",
         back_populates="loan",
     )
 
+    loan_repayment_schedules = relationship(
+        "LoanRepaymentSchedule",
+        primaryjoin="LoanRepaymentSchedule.loan_id == Loan.id",
+        foreign_keys="LoanRepaymentSchedule.loan_id",
+        back_populates="loan",
+    )
+
+
     @classmethod
     def create_loan(
         cls,
@@ -92,7 +100,6 @@ class Loan(db.Model):
             raise ValueError(f"Database integrity error: {err}")
         return loan
 
-
     @classmethod
     def has_active_loans(cls, customer_id):
         active_loans = cls.query.filter_by(
@@ -143,6 +150,9 @@ class Loan(db.Model):
             'defaultPenaltyFee': self.default_penalty_fee,
             'continuousFee': self.continuous_fee,
             'collectionType': self.collection_type,
+            'upfrontFee': self.upfront_fee,
+            'repaymentAmount': self.repayment_amount,
+            'installmentAmount': self.installment_amount,
             'status': self.status,
             'dueDate': self.due_date.isoformat() if self.due_date else None,
             'loanDate': self.created_at.isoformat() if self.created_at else None,

app/models/loan_charge.py

@@ -1,6 +1,7 @@
 from datetime import datetime, timezone, timedelta
 from app.extensions import db
 from sqlalchemy.orm import relationship
+from app.utils.logger import logger
 
 
 class LoanCharge(db.Model):
@@ -35,8 +36,8 @@ class LoanCharge(db.Model):
             charges (list): A list of dictionaries with keys: 
             code (str), amount (float), percent (float), description (str), due (int)
         """
-        if not charges or not isinstance(charges, list):
-            raise ValueError("Charges must be a non-empty list of dictionaries")
+        # if not charges or not isinstance(charges, list):
+        #     raise ValueError("Charges must be a non-empty list of dictionaries")
         
         if loan_id is None:
             raise ValueError("loan_id cannot be None")
@@ -44,21 +45,23 @@ class LoanCharge(db.Model):
         loan_charges = []
         now = datetime.now(timezone.utc)
 
-        for charge in charges:
-            due_days = getattr(charge, "due", 0)
-            amount = getattr(charge, "amount", 0.0)
-            percent = getattr(charge, "percent", 0.0)
 
-            if amount == 0.0:
-                amount = (percent / 100.0) * referenced_amount
+        subset_keys = ['interest', 'management', 'insurance', 'vat']
+        for item in subset_keys:
+            charge =  charges[item]
+            due_days = charge['due_days'] #  getattr(charge, "due_days", 0)
+            amount =  charge['fee'] # getattr(charge, "fee", 0.0)
+            percent =  charge['rate'] # getattr(charge, "rate", 0.0)
+            code =  charge['code'] # getattr(charge, "code","")
+            description =  charge['description'] # getattr(charge, "description", "")
 
             charge_obj = cls(
                 loan_id = loan_id,
                 transaction_id = transaction_id,
-                code = getattr(charge, "code"),
+                code = code,
                 amount = round(amount, 2),
                 percent = percent,
-                description = getattr(charge, "description", ""),
+                description = description,
                 due = due_days,
                 due_date = now + timedelta(days=due_days)
             )

app/models/loan_repayment_schedule.py

@@ -0,0 +1,68 @@
+from datetime import datetime, timezone
+from app.extensions import db
+from sqlalchemy.orm import relationship
+from dateutil.relativedelta import relativedelta
+
+class LoanRepaymentSchedule(db.Model):
+    __tablename__ = 'loan_repayment_schedules'
+
+    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
+    loan_id = db.Column(db.Integer, nullable=False)
+    product_id = db.Column(db.String(20), nullable=True)
+    installment_number = db.Column(db.Integer, nullable=False)
+    due_date = db.Column(db.DateTime, nullable=False)
+    installment_amount= db.Column(db.Float, default=0.0)
+    total_repayment_amount = db.Column(db.Float, default=0.0)
+    paid = db.Column(db.Boolean, default=False)
+    paid_at = db.Column(db.DateTime, nullable=True)
+
+    created_at = db.Column(db.DateTime, default=datetime.now(timezone.utc))
+    updated_at = db.Column(db.DateTime, default=datetime.now(timezone.utc), onupdate=datetime.now(timezone.utc))
+
+    loan = relationship(
+        "Loan",
+        primaryjoin="LoanRepaymentSchedule.loan_id == Loan.id",
+        foreign_keys=[loan_id],
+        back_populates="loan_repayment_schedules",
+    )
+
+
+    @classmethod
+    def add_repayment_schedule(cls, loan, tenor):
+        """
+        Add repayment schedules for a given loan.
+        """
+        now = datetime.now(timezone.utc)
+        schedules = []
+
+        for i in range(tenor):
+            due_date = now + relativedelta(months=i + 1)
+            schedule = LoanRepaymentSchedule(
+                loan_id=loan.id,
+                installment_number=i + 1,
+                due_date=due_date,
+                total_repayment_amount = round(loan.repayment_amount, 2),
+                installment_amount=round(loan.installment_amount, 2),
+                product_id = loan.product_id
+            )
+            
+            db.session.add(schedule)
+            schedules.append(schedule)
+
+        return schedules
+
+    def to_dict(self):
+        return {
+            'id': self.id,
+            'loanId': self.loan_id,
+            'installmentNumber': self.installment_number,
+            'dueDate': self.due_date.isoformat(),
+            'principalAmount': self.principal_amount,
+            'interestAmount': self.interest_amount,
+            'totalInstallment': self.total_installment,
+            'paid': self.paid,
+            'paidAt': self.paid_at.isoformat() if self.paid_at else None
+        }
+
+    def __repr__(self):
+        return f'<LoanRepaymentSchedule Loan:{self.loan_id} Installment:{self.installment_number}>'

app/models/offer.py

@@ -12,6 +12,10 @@ class Offer(db.Model):
     max_amount = db.Column(db.Float, nullable=False)
     tenor = db.Column(db.Integer, nullable=False)
     schedule = db.Column(db.Integer, nullable=True)
+    interest_rate = db.Column(db.Float, default=3.0)
+    management_rate = db.Column(db.Float, default=1.0)
+    insurance_rate = db.Column(db.Float, default=1.0)
+    vat_rate = db.Column(db.Float, default=7.5)
     list_order = db.Column(db.Integer, nullable=True)
     created_at = db.Column(db.DateTime, default=datetime.now(timezone.utc))
     updated_at = db.Column(db.DateTime, default=datetime.now(timezone.utc), onupdate=datetime.now(timezone.utc))
@@ -72,8 +76,10 @@ class Offer(db.Model):
             "minAmount": self.min_amount,
             "maxAmount": self.max_amount,
             "tenor": self.tenor,
-            "schedule": self.schedule,
-            "list_order": self.list_order
+            "interest_rate": self.interest_rate,
+            "management_rate": self.management_rate,
+            "insurance_rate": self.insurance_rate,
+            "vat_rate": self.vat_rate
         }
     
     def __repr__(self):

app/swagger/schemas/LoanStatusResponse.json

@@ -47,13 +47,26 @@
                     "productId": {
                         "type": "string",
                         "example": "101"
+                    },
+                    "installment": {
+            "type": "array",
+            "items": {
+                "type": "object",
+                "properties": {
+                    "amount": {
+                        "type": "number",
+                        "format": "float",
+                        "example": 10000.0
+                    },
+                    "repaymentDate": {
+                        "type": "string",
+                        "example": "2025-04-24 10:31:"
                     }
                 }
             }
-        },
-        "totalDebtAmount": {
-            "type": "integer",
-            "example": 8500
+        }
+                }
+            }
         },
         "resultCode": {
             "type": "string",

app/swagger/schemas/SelectOfferResponse.json

@@ -35,6 +35,10 @@
                         "format": "float",
                         "example": 10000.0
                     },
+                    "dueDate": {
+                        "type": "string",
+                        "example": "2025-04-24 10:31:"
+                    },
                     "upfrontPayment": {
                         "type": "number",
                         "format": "float",
@@ -75,7 +79,7 @@
                         "format": "float",
                         "example": 100.0
                     },
-                    "recommendedRepaymentDates": {
+                    "installmentRepaymentDates": {
                         "type": "array",
                         "items": {
                             "type": "string"

migrations/versions/1b2339f43824_migration_on_thu_apr_24_17_42_25_utc_.py

@@ -33,12 +33,6 @@ def upgrade():
                existing_type=sa.NUMERIC(precision=10, scale=2),
                type_=sa.Float(),
                existing_nullable=True)
-
-    with op.batch_alter_table('loans', schema=None) as batch_op:
-        batch_op.add_column(sa.Column('upfront_fee', sa.Float(), nullable=True))
-        batch_op.add_column(sa.Column('repayment_amount', sa.Float(), nullable=True))
-        batch_op.add_column(sa.Column('installment_amount', sa.Float(), nullable=True))
-
     # ### end Alembic commands ###
 
 

migrations/versions/2a45dd99c9cb_migration_on_fri_apr_25_15_01_00_utc_.py

@@ -0,0 +1,42 @@
+"""Migration on Fri Apr 25 15:01:00 UTC 2025
+
+Revision ID: 2a45dd99c9cb
+Revises: 2cf0c177ca02
+Create Date: 2025-04-25 15:01:51.129681
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '2a45dd99c9cb'
+down_revision = '2cf0c177ca02'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('loan_repayment_schedules', schema=None) as batch_op:
+        batch_op.add_column(sa.Column('product_id', sa.String(length=20), nullable=True))
+        batch_op.add_column(sa.Column('installment_amount', sa.Float(), nullable=True))
+        batch_op.add_column(sa.Column('total_repayment_amount', sa.Float(), nullable=True))
+        batch_op.drop_column('principal_amount')
+        batch_op.drop_column('interest_amount')
+        batch_op.drop_column('total_installment')
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('loan_repayment_schedules', schema=None) as batch_op:
+        batch_op.add_column(sa.Column('total_installment', sa.DOUBLE_PRECISION(precision=53), autoincrement=False, nullable=True))
+        batch_op.add_column(sa.Column('interest_amount', sa.DOUBLE_PRECISION(precision=53), autoincrement=False, nullable=True))
+        batch_op.add_column(sa.Column('principal_amount', sa.DOUBLE_PRECISION(precision=53), autoincrement=False, nullable=True))
+        batch_op.drop_column('total_repayment_amount')
+        batch_op.drop_column('installment_amount')
+        batch_op.drop_column('product_id')
+
+    # ### end Alembic commands ###

migrations/versions/2cf0c177ca02_migration_on_fri_apr_25_14_02_01_utc_.py

@@ -0,0 +1,41 @@
+"""Migration on Fri Apr 25 14:02:01 UTC 2025
+
+Revision ID: 2cf0c177ca02
+Revises: 1b2339f43824
+Create Date: 2025-04-25 14:02:42.244146
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '2cf0c177ca02'
+down_revision = '1b2339f43824'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('loan_repayment_schedules',
+    sa.Column('id', sa.Integer(), autoincrement=True, nullable=False),
+    sa.Column('loan_id', sa.Integer(), nullable=False),
+    sa.Column('installment_number', sa.Integer(), nullable=False),
+    sa.Column('due_date', sa.DateTime(), nullable=False),
+    sa.Column('principal_amount', sa.Float(), nullable=True),
+    sa.Column('interest_amount', sa.Float(), nullable=True),
+    sa.Column('total_installment', sa.Float(), nullable=True),
+    sa.Column('paid', sa.Boolean(), nullable=True),
+    sa.Column('paid_at', sa.DateTime(), nullable=True),
+    sa.Column('created_at', sa.DateTime(), nullable=True),
+    sa.Column('updated_at', sa.DateTime(), nullable=True),
+    sa.PrimaryKeyConstraint('id')
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table('loan_repayment_schedules')
+    # ### end Alembic commands ###

migrations/versions/89759cebb9c6_migration_on_sat_apr_26_12_50_46_utc_.py

@@ -0,0 +1,38 @@
+"""Migration on Sat Apr 26 12:50:46 UTC 2025
+
+Revision ID: 89759cebb9c6
+Revises: 2a45dd99c9cb
+Create Date: 2025-04-26 12:50:49.771355
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '89759cebb9c6'
+down_revision = '2a45dd99c9cb'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('offers', schema=None) as batch_op:
+        batch_op.add_column(sa.Column('interest_rate', sa.Float(), nullable=True))
+        batch_op.add_column(sa.Column('management_rate', sa.Float(), nullable=True))
+        batch_op.add_column(sa.Column('insurance_rate', sa.Float(), nullable=True))
+        batch_op.add_column(sa.Column('vat_rate', sa.Float(), nullable=True))
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('offers', schema=None) as batch_op:
+        batch_op.drop_column('vat_rate')
+        batch_op.drop_column('insurance_rate')
+        batch_op.drop_column('management_rate')
+        batch_op.drop_column('interest_rate')
+
+    # ### end Alembic commands ###