# Part of Odoo. See LICENSE file for full copyright and licensing details.

import importlib
import importlib.util
import io
import logging
import re
import unicodedata
from xml.etree import ElementTree

from odoo import _, models
from odoo.exceptions import UserError

_logger = logging.getLogger(__name__)
if not importlib.util.find_spec('ofxparse'):
    _logger.warning("The ofxparse python library is not installed, ofx import will not work.")


class AccountJournal(models.Model):
    _inherit = 'account.journal'

    def _get_bank_statements_available_import_formats(self):
        rslt = super(AccountJournal, self)._get_bank_statements_available_import_formats()
        rslt.append('OFX')
        return rslt

    def _check_ofx(self, raw_file):
        if (raw_file or b'').startswith(b"OFXHEADER"):
            #v1 OFX
            return True
        try:
            #v2 OFX
            return b"<ofx>" in (raw_file or b'').lower()
        except ElementTree.ParseError:
            return False

    def _fill_transaction_vals_line_ofx(self, transaction, length_transactions, partner_bank):
        return {
            'date': transaction.date,
            'payment_ref': transaction.payee + (transaction.memo and ': ' + transaction.memo or ''),
            'ref': transaction.id,
            'amount': float(transaction.amount),
            'unique_import_id': transaction.id,
            'account_number': partner_bank.acc_number,
            'partner_id': partner_bank.partner_id.id,
            'sequence': length_transactions + 1,
        }

    def _parse_bank_statement_file(self, raw_file):
        if not self._check_ofx(raw_file):
            return super()._parse_bank_statement_file(raw_file)
        try:
            from odoo.addons.account_bank_statement_import_ofx.ofx_parser import OfxParser  # noqa: PLC0415
        except ImportError as e:
            raise UserError(_("The library 'ofxparse' is missing, OFX import cannot proceed.")) from e

        try:
            ofx = OfxParser.parse(io.BytesIO(raw_file))
        except UnicodeDecodeError:
            # Replacing utf-8 chars with ascii equivalent
            encoding = re.findall(rb'encoding="(.*?)"', raw_file)
            encoding = encoding[0] if len(encoding) > 1 else 'utf-8'
            try:
                raw_file = unicodedata.normalize('NFKD', raw_file.decode(encoding)).encode('ascii', 'ignore')
                ofx = OfxParser.parse(io.BytesIO(raw_file))
            except UnicodeDecodeError:
                raise UserError(_("There was an issue decoding the file. Please check the file encoding."))
        vals_bank_statement = []
        account_lst = set()
        currency_lst = set()
        # Since ofxparse doesn't provide account numbers, we'll have to find res.partner and res.partner.bank here
        # (normal behaviour is to provide 'account_number', which the generic module uses to find partner/bank)
        transaction_payees = [
            transaction.payee
            for account in ofx.accounts
            for transaction in account.statement.transactions
        ]
        partner_banks_dict = {
            partner_bank.partner_id.name: partner_bank
            for partner_bank in self.env['res.partner.bank'].search([
                ('partner_id.name', 'in', transaction_payees)
            ])
        }
        for account in ofx.accounts:
            account_lst.add(account.number)
            currency_lst.add(account.statement.currency)
            transactions = []
            total_amt = 0.00
            for transaction in account.statement.transactions:
                partner_bank = partner_banks_dict.get(transaction.payee, self.env['res.partner.bank'])
                vals_line = self._fill_transaction_vals_line_ofx(transaction, len(transactions), partner_bank)
                total_amt += float(transaction.amount)
                transactions.append(vals_line)

            vals_bank_statement.append({
                'transactions': transactions,
                # WARNING: the provided ledger balance is not necessarily the ending balance of the statement
                # see https://github.com/odoo/odoo/issues/3003
                'balance_start': float(account.statement.balance) - total_amt,
                'balance_end_real': account.statement.balance,
            })

        if account_lst and len(account_lst) == 1:
            account_lst = account_lst.pop()
            currency_lst = currency_lst.pop()
        else:
            account_lst = None
            currency_lst = None

        return [[currency_lst, account_lst, vals_bank_statement]]