import logging
from datetime import datetime

from flask import jsonify

from app.models.transaction_offers import TransactionOffer

logger = logging.getLogger(__name__)


class TransactionOfferService:
    """
    Service class for handling transaction offer-related operations.
    """

    @staticmethod
    def process_request(filters=None):
        """
        Process the get transaction offers request.

        Args:
            filters (dict, optional): Filters for the transaction offers query.

        Returns:
            dict: A standardized response with transaction offers data.
        """
        try:
            if filters is None:
                filters = {}

            # Extract filters
            customer_id = filters.get('customer_id')
            transaction_id = filters.get('transaction_id')
            offer_id = filters.get('offer_id')
            product_id = filters.get('product_id')
            original_transaction = filters.get('original_transaction')
            start_date = filters.get('start_date')
            end_date = filters.get('end_date')

            # Extract pagination parameters
            page = int(filters.get('page', 1))
            limit = int(filters.get('limit', 20))

            # Ensure page and limit are valid
            if page < 1:
                page = 1
            if limit < 1 or limit > 100:
                limit = 20

            # Convert string dates to datetime objects if provided
            if start_date and isinstance(start_date, str):
                start_date = datetime.fromisoformat(start_date.replace('Z', '+00:00'))
            if end_date and isinstance(end_date, str):
                end_date = datetime.fromisoformat(end_date.replace('Z', '+00:00'))

            # Get transaction offers with optional filters and pagination
            transaction_offers, total_count = TransactionOffer.get_all_transaction_offers(
                customer_id=customer_id,
                transaction_id=transaction_id,
                offer_id=offer_id,
                product_id=product_id,
                original_transaction=original_transaction,
                start_date=start_date,
                end_date=end_date,
                page=page,
                limit=limit
            )

            # Convert transaction offers to dictionary format
            transaction_offers_data = []
            for offer in transaction_offers:
                transaction_offers_data.append({
                    'id': offer.id,
                    'customer_id': offer.customer_id,
                    'transaction_id': offer.transaction_id,
                    'original_transaction': offer.original_transaction,
                    'offer_id': offer.offer_id,
                    'product_id': offer.product_id,
                    'min_amount': offer.min_amount,
                    'max_amount': offer.max_amount,
                    'eligible_amount': offer.eligible_amount,
                    'tenor': offer.tenor,
                    'created_at': offer.created_at.isoformat() if offer.created_at else None,
                    'updated_at': offer.updated_at.isoformat() if offer.updated_at else None
                })

            # Calculate total pages
            total_pages = (total_count + limit - 1) // limit

            response_data = {
                'transaction_offers': transaction_offers_data,
                'count': len(transaction_offers_data),
                'pagination': {
                    'total_count': total_count,
                    'total_pages': total_pages,
                    'current_page': page,
                    'limit': limit,
                    'has_next': page < total_pages,
                    'has_prev': page > 1
                }
            }

            return response_data

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