from flask import request, jsonify
from marshmallow import ValidationError
from app.api.integrations.kafka import KafkaIntegration
from app.api.services.base_service import BaseService
from app.api.enums import TransactionType   
from app.utils.logger import logger
from app.api.schemas.provide_loan import ProvideLoanSchema
from threading import Thread
from app.models.loan import Loan
from app.api.enums import LoanStatus
from app.extensions import db

class ProvideLoanService(BaseService):
    TRANSACTION_TYPE = TransactionType.PROVIDE_LOAN 


    @staticmethod
    def process_request(data):
        """
        Process the ProvideLoan request.

        Args:
            data (dict): The request data.

        Returns:
            dict: A standardized response.
        """
        try:
            with db.session.begin():
                validated_data = ProvideLoanService.validate_data(data, ProvideLoanSchema())
                account_id = validated_data.get('accountId')
                customer_id =  validated_data.get('customerId')
                request_id =  validated_data.get('requestId')
                transaction_id = validated_data.get('transactionId')

                if (ProvideLoanService.validate_account_ownership(account_id = account_id, customer_id = customer_id)):

                
                    # Save the loan details  
                    loan = Loan.create_loan(
                        customer_id=customer_id,
                        account_id=account_id,
                        offer_id=validated_data.get('offerId'),
                        principal_amount=validated_data.get('requestedAmount'),
                        status=LoanStatus.ACTIVE
                    )

                    if not loan:
                        logger.error(f"Failed to save loan details")
                        return jsonify({
                            "message": "Failed to save loan details."
                        }), 400
                    
                    db.session.flush()
                    validated_data['refId'] = loan.id
                    validated_data['refModel'] = "loan"
                    
                    # Log Transaction
                    transaction = ProvideLoanService.log_transaction(validated_data = validated_data)

                    if not transaction:
                        logger.error(f"Failed to log transaction")
                        return jsonify({
                            "message": "Failed to log transaction."
                        }), 400

            
                    
                else: 
                    return jsonify({
                            "message": "Invalid Customer or Account"
                        }), 400
            
            
                response_data = {
                    "requestId": request_id,
                    "transactionId": transaction_id,
                    "customerId": customer_id,
                    "accountId": account_id,
                    "msisdn": "3451342",
                    "resultCode": "00",
                    "resultDescription": "Successful"
                    }


                # KafkaIntegration.send_loan_request(loan_data = response_data, request_id = request_id)
                # Call Kafka in a background thread
                thread = Thread(target=ProvideLoanService.async_send_to_kafka, args=(response_data, request_id, "PROCESS_PAYMENT"))
                thread.start()

                db.session.commit()
                return response_data

        except ValidationError as err:

            logger.error(f"Validation Error: {getattr(err, 'messages', str(err))}")
            db.session.rollback() 

            return jsonify({
                "message": "Validation exception"
                }) , 422
        
        except  ValueError as err:
            logger.error(f"{getattr(err, 'messages', str(err))}")
            db.session.rollback() 

            return jsonify({
                "message": str(err)
                }) , 400

        except Exception as e:
            logger.error(f"An error occurred: {str(e)}", exc_info=True)
            db.session.rollback() 
            return jsonify({
                "message": "Internal Server Error"
                }) , 500