# -*- coding: utf-8 -*-

import logging

from odoo import api, fields, models, _
from odoo.exceptions import ValidationError, UserError

_logger = logging.getLogger(__name__)


class ResPartner(models.Model):
    _inherit = 'res.partner'

    property_account_income_customer_id = fields.Many2one(
        'account.account',
        company_dependent=True,
        string='Customer Income Account',
        domain="[('account_type', '=', 'income'), ('deprecated', '=', False)]",
        help="This account will be used for revenue entries when selling to this customer. "
             "If not set, the income account from the product category will be used."
    )
    
    property_account_expense_customer_id = fields.Many2one(
        'account.account',
        company_dependent=True,
        string='Customer Expense Account (COGS)',
        domain="[('account_type', '=', 'expense'), ('deprecated', '=', False)]",
        help="This account will be used for COGS entries when selling to this customer. "
             "If not set, the expense account from the product category will be used."
    )

    def _get_customer_income_account(self):
        """
        Returns the customer-specific income account if defined.
        Validates that the account is active and usable.
        
        Returns:
            account.account recordset or False if not defined
            
        Raises:
            UserError: If the account is inactive or invalid
        """
        self.ensure_one()
        
        try:
            account = self.property_account_income_customer_id
            
            if not account:
                return False
            
            # Runtime validation: Check if account is still active
            if account.deprecated:
                _logger.error(
                    "Customer income account %s (ID: %s) for partner %s (ID: %s) is deprecated",
                    account.code, account.id, self.name, self.id
                )
                raise UserError(_(
                    "The customer income account '%s' for customer '%s' is inactive. "
                    "Please update the customer's accounting settings before creating invoices."
                ) % (account.display_name, self.name))
            
            # Runtime validation: Check company match
            # In Odoo 18, account.account uses company_ids (Many2many)
            if account.company_ids and self.company_id and self.company_id not in account.company_ids:
                _logger.error(
                    "Customer income account %s (Companies: %s) for partner %s (Company: %s) has company mismatch",
                    account.code, account.company_ids.mapped('name'), self.name, self.company_id.name
                )
                raise UserError(_(
                    "The customer income account '%s' does not belong to company '%s'. "
                    "Please update the customer's accounting settings."
                ) % (account.display_name, self.company_id.name))
            
            return account
            
        except UserError:
            # Re-raise UserError as-is
            raise
        except Exception as e:
            # Log unexpected errors and return False to fall back to standard behavior
            _logger.warning(
                "Unexpected error retrieving customer income account for partner %s (ID: %s): %s. "
                "Falling back to product category account.",
                self.name, self.id, str(e)
            )
            return False

    def _get_customer_expense_account(self):
        """
        Returns the customer-specific expense account if defined.
        Validates that the account is active and usable.
        
        Returns:
            account.account recordset or False if not defined
            
        Raises:
            UserError: If the account is inactive or invalid
        """
        self.ensure_one()
        
        try:
            account = self.property_account_expense_customer_id
            
            if not account:
                return False
            
            # Runtime validation: Check if account is still active
            if account.deprecated:
                _logger.error(
                    "Customer expense account %s (ID: %s) for partner %s (ID: %s) is deprecated",
                    account.code, account.id, self.name, self.id
                )
                raise UserError(_(
                    "The customer expense account '%s' for customer '%s' is inactive. "
                    "Please update the customer's accounting settings before processing deliveries."
                ) % (account.display_name, self.name))
            
            # Runtime validation: Check company match
            # In Odoo 18, account.account uses company_ids (Many2many)
            if account.company_ids and self.company_id and self.company_id not in account.company_ids:
                _logger.error(
                    "Customer expense account %s (Companies: %s) for partner %s (Company: %s) has company mismatch",
                    account.code, account.company_ids.mapped('name'), self.name, self.company_id.name
                )
                raise UserError(_(
                    "The customer expense account '%s' does not belong to company '%s'. "
                    "Please update the customer's accounting settings."
                ) % (account.display_name, self.company_id.name))
            
            return account
            
        except UserError:
            # Re-raise UserError as-is
            raise
        except Exception as e:
            # Log unexpected errors and return False to fall back to standard behavior
            _logger.warning(
                "Unexpected error retrieving customer expense account for partner %s (ID: %s): %s. "
                "Falling back to product category account.",
                self.name, self.id, str(e)
            )
            return False

    @api.constrains('property_account_income_customer_id')
    def _check_income_account(self):
        """
        Validate that the customer income account is of type 'income',
        not deprecated, and belongs to the correct company.
        """
        for partner in self:
            account = partner.property_account_income_customer_id
            if account:
                # Check account type
                if account.account_type != 'income':
                    raise ValidationError(_(
                        "The selected income account '%s' must be of type 'Income'. "
                        "Please select a valid income account."
                    ) % account.display_name)
                
                # Check if account is deprecated
                if account.deprecated:
                    raise ValidationError(_(
                        "The selected income account '%s' is deprecated and cannot be used. "
                        "Please select an active income account."
                    ) % account.display_name)
                
                # Check company match in multi-company setup
                # In Odoo 18, account.account uses company_ids (Many2many)
                if account.company_ids and partner.company_id and partner.company_id not in account.company_ids:
                    raise ValidationError(_(
                        "The selected income account '%s' does not belong to company '%s'. "
                        "Please select an account from the correct company."
                    ) % (account.display_name, partner.company_id.name))

    @api.constrains('property_account_expense_customer_id')
    def _check_expense_account(self):
        """
        Validate that the customer expense account is of type 'expense',
        not deprecated, and belongs to the correct company.
        """
        for partner in self:
            account = partner.property_account_expense_customer_id
            if account:
                # Check account type
                if account.account_type != 'expense':
                    raise ValidationError(_(
                        "The selected expense account '%s' must be of type 'Expense'. "
                        "Please select a valid expense account."
                    ) % account.display_name)
                
                # Check if account is deprecated
                if account.deprecated:
                    raise ValidationError(_(
                        "The selected expense account '%s' is deprecated and cannot be used. "
                        "Please select an active expense account."
                    ) % account.display_name)
                
                # Check company match in multi-company setup
                # In Odoo 18, account.account uses company_ids (Many2many)
                if account.company_ids and partner.company_id and partner.company_id not in account.company_ids:
                    raise ValidationError(_(
                        "The selected expense account '%s' does not belong to company '%s'. "
                        "Please select an account from the correct company."
                    ) % (account.display_name, partner.company_id.name))