#!/usr/bin/env python3
"""
Data mapper for NEFT SFTP feed.
Maps parsed NEFT transactions (dicts) to NEFTOutwardRecord for database insertion.
- No padding of account numbers (kept as-is, trimmed).
"""

from datetime import datetime
from decimal import Decimal
from typing import Dict, Any, List

from logging_config import get_logger
from db.models import NEFTOutwardRecord  

logger = get_logger(__name__)


class NEFTDataMapper:
    """Maps parsed NEFT transactions to NEFTOutwardRecord objects."""

    # -------------------------
    # Helpers
    # -------------------------

    @staticmethod
    def convert_date(date_str: str) -> str:
        """
        Convert NEFT date (YYYYMMDD) to DDMMYYYY.

        Input : '20260306'
        Output: '06032026'

        On error, returns today's date in DDMMYYYY format.
        """
        try:
            if not date_str or len(date_str.strip()) != 8 or not date_str.isdigit():
                raise ValueError(f"Invalid NEFT date format: {date_str!r}")
            dt = datetime.strptime(date_str, "%Y%m%d")
            return dt.strftime("%d%m%Y")
        except Exception as e:
            logger.error(f"Error converting date '{date_str}': {e}")
            return datetime.now().strftime("%d%m%Y")


   
    @staticmethod
    def pad_account_number(account_number: str) -> str:
        """
        Pad account number with leading zeroes to make it 17 digits.

        Args:
            account_number: Account number string

        Returns:
            Account number padded to 17 digits with leading zeroes
        """
        try:
            if not account_number:
                return '0' * 17
            # Remove any existing spaces and pad to 17 digits
            clean_account = account_number.strip()
            return clean_account.zfill(17)
        except Exception as e:
            logger.error(f"Error padding account number '{account_number}': {e}")
            return '0' * 17


    @staticmethod
    def convert_amount(amount_in: Any) -> Decimal:
        """
        Convert amount to Decimal and return absolute value.
        Use TXNIND to capture the sign semantics.
        """
        try:
            if isinstance(amount_in, Decimal):
                val = amount_in
            else:
                txt = (str(amount_in) or '').replace(',', '').strip()
                val = Decimal(txt) if txt else Decimal('0')
            return abs(val)
        except Exception as e:
            logger.error(f"Error converting amount '{amount_in}': {e}")
            return Decimal('0')

    # -------------------------
    # Mapping
    # -------------------------

    @classmethod
    def map_transaction(cls, parsed_txn: Dict[str, Any], bankcode: str) -> NEFTOutwardRecord:
        """
        Map a single parsed NEFT transaction (dict) to NEFTOutwardRecord.

        Args:
            parsed_txn: Dict emitted by SFTPUtrParser
            bankcode  : Bank code for this transaction (mapped to NEFTOutwardRecord.bank_code)
        """
        try:
            # Amount handling
            amount_in = parsed_txn.get('amount', '0')
            txn_amt = cls.convert_amount(amount_in)
            txnind = 'DR'
            sender_to_reciver_info = '  '

            # Date handling
            txn_date_raw = parsed_txn.get('tran_date', '') or ''
            txn_date_ddmmyyyy = cls.convert_date(txn_date_raw)

            
            #sender_acct = (parsed_txn.get('remitter_acct_no') or '').strip()
            sender_account = parsed_txn.get('remitter_acct_no','') or ''
            sender_acct = cls.pad_account_number(sender_account)

            # Account numbers: NO padding, just trim
            recvr_acct = (parsed_txn.get('benef_acct_no') or '').strip()          

           
            recvr_acct_name = (parsed_txn.get('beneficiary_details') or '').strip()

            record = NEFTOutwardRecord(
                
                bank_code=bankcode,
                txnind=txnind,
                jrnl_id=(parsed_txn.get('journal_no') or '').strip(),
                ref_no=(parsed_txn.get('utr') or '').strip(),
                txn_date=txn_date_ddmmyyyy,
                txn_amt=txn_amt,
                sender_ifsc=(parsed_txn.get('ifsc_sender') or '').strip(),
                reciever_ifsc=(parsed_txn.get('ifsc_recvr') or '').strip(),
                sender_acct_no=sender_acct,
                sender_acct_name=(parsed_txn.get('sender_acct_name') or '').strip(),                
                recvr_acct_no=recvr_acct,
                recvr_acct_name=recvr_acct_name,                
                reject_code=(parsed_txn.get('reject_code') or '').strip(),
                reject_reason=(parsed_txn.get('reject_reason') or '').strip(),
                benef_address=(parsed_txn.get('benef_address') or '').strip(),
                msg_type=(parsed_txn.get('sub_msg_type') or '').strip(),
                sender_to_reciver_info=sender_to_reciver_info,
            )

            return record

        except Exception as e:
            logger.error(f"Error mapping NEFT transaction: {e}", exc_info=True)
            raise

    @classmethod
    def map_transactions(cls, parsed_transactions: List[Dict[str, Any]], bankcode: str) -> List[NEFTOutwardRecord]:
        """
        Map a list of parsed NEFT transactions to NEFTOutwardRecord objects.

        Args:
            parsed_transactions: List of dicts from SFTPUtrParser
            bankcode           : Bank code to be applied to each record
        """
        records: List[NEFTOutwardRecord] = []
        for txn in parsed_transactions:
            try:
                rec = cls.map_transaction(txn, bankcode)
                records.append(rec)
            except Exception as e:
                logger.warning(f"Skipping transaction due to error: {e}")
        logger.info(f"Mapped {len(records)} NEFT transactions for bank {bankcode}")
        return records