from odoo import api, fields, models, _


class AccountPayment(models.Model):
    _inherit = 'account.payment'

    # Computed residual amount field
    payment_residual = fields.Monetary(
        string='Payment Residual',
        compute='_compute_payment_residual',
        currency_field='currency_id',
        help="Residual amount of this payment (amount not yet reconciled)",
        readonly=True
    )

    payment_residual_currency = fields.Monetary(
        string='Payment Residual Currency',
        compute='_compute_payment_residual',
        currency_field='currency_id',
        help="Residual amount in payment currency",
        readonly=True
    )

    @api.depends('move_id.line_ids.amount_residual',
                 'move_id.line_ids.amount_residual_currency',
                 'move_id.line_ids.reconciled',
                 'is_matched')
    def _compute_payment_residual(self):
        """Compute the residual amount from payment journal items
        
        Shows 0 residual when payment is matched with bank statement.
        Otherwise shows the residual from all reconcilable lines except liquidity accounts.
        """
        for pay in self:
            # If payment is matched with bank statement, no residual to show
            if pay.is_matched:
                pay.payment_residual = 0.0
                pay.payment_residual_currency = 0.0
                continue
                
            if not pay.move_id:
                pay.payment_residual = 0.0
                pay.payment_residual_currency = 0.0
                continue
            
            # Get all reconcilable lines except liquidity accounts
            # This includes receivable, payable, and other reconcilable accounts
            # but excludes bank/cash accounts that get matched with statements
            reconcilable_lines = pay.move_id.line_ids.filtered(
                lambda line: line.account_id.reconcile and 
                line.account_id.account_type not in ('asset_cash', 'liability_credit_card')
            )
            
            # Calculate residual based on currency
            residual = 0.0
            residual_currency = 0.0
            
            for line in reconcilable_lines:
                # Always add to company currency residual
                residual += line.amount_residual
                
                # For foreign currency, use amount_residual_currency
                if line.currency_id and line.currency_id != pay.company_id.currency_id:
                    residual_currency += line.amount_residual_currency
                else:
                    residual_currency += line.amount_residual
            
            # Store absolute values
            pay.payment_residual = abs(residual)
            pay.payment_residual_currency = abs(residual_currency)