from odoo import api, fields, models
from odoo.tools import float_compare

class MrpProduction(models.Model):
    _inherit = 'mrp.production'


    packaging_id = fields.Many2one('mrp.packaging', string='Packaging', domain="[('product_tmpl_id', '=', product_tmpl_id)]", check_company=True)
    packaging_qty = fields.Float('Quantity Packaging', compute='_compute_packaging_qty', inverse='_inverse_packaging_qty', store=True, readonly=False)

    @api.depends('product_qty', 'packaging_id', 'packaging_id.qty')
    def _compute_packaging_qty(self):
        for record in self:
            if record.packaging_id and record.packaging_id.qty:
                new_qty = record.product_qty / record.packaging_id.qty
                if float_compare(new_qty, record.packaging_qty, precision_digits=2) != 0:
                    record.packaging_qty = new_qty
            else:
                record.packaging_qty = 0.0

    def _inverse_packaging_qty(self):
        for record in self:
            if record.packaging_id and record.packaging_id.qty:
                record.product_qty = record.packaging_qty * record.packaging_id.qty

    qty_producing_packaging = fields.Float('Quantity Producing Packaging', compute='_compute_qty_producing_packaging', inverse='_inverse_qty_producing_packaging', digits=(16, 2))

    @api.depends('qty_producing', 'packaging_id', 'packaging_id.qty')
    def _compute_qty_producing_packaging(self):
        for record in self:
            if record.packaging_id and record.packaging_id.qty:
                record.qty_producing_packaging = record.qty_producing / record.packaging_id.qty
            else:
                record.qty_producing_packaging = 0.0

    def _inverse_qty_producing_packaging(self):
        for record in self:
            if record.packaging_id and record.packaging_id.qty:
                record.qty_producing = record.qty_producing_packaging * record.packaging_id.qty
                record._merge_finished_move_lines()

    @api.onchange('qty_producing_packaging')
    def _onchange_qty_producing_packaging(self):
        if self.packaging_id and self.packaging_id.qty:
            self.qty_producing = self.qty_producing_packaging * self.packaging_id.qty
            self._onchange_qty_producing()
            self._merge_finished_move_lines()

    @api.onchange('qty_producing')
    def _onchange_qty_producing(self):
        super()._onchange_qty_producing()
        self._merge_finished_move_lines()

    def write(self, vals):
        res = super().write(vals)
        if 'qty_producing' in vals or 'qty_producing_packaging' in vals:
            self._merge_finished_move_lines()
        return res

    def _set_qty_producing(self, *args, **kwargs):
        res = super()._set_qty_producing(*args, **kwargs)
        self._merge_finished_move_lines()
        return res

    def _post_inventory(self, *args, **kwargs):
        res = super()._post_inventory(*args, **kwargs)
        self._merge_finished_move_lines()
        return res

    def _merge_finished_move_lines(self):
        for production in self:
            # Process ALL finished moves, even DONE ones, to catch splits that happened during validation
            moves = production.move_finished_ids.filtered(lambda m: m.product_id == production.product_id and m.state != 'cancel')
            for move in moves:
                # print(f"DEBUG MERGE: Processing move {move.id}, lines found: {len(move.move_line_ids)}")
                lines_by_key = {}
                # track lines to unlink or zero-out (if done)
                
                # Keep the original line (smallest ID) to preserve consistency
                sorted_lines = move.move_line_ids.sorted('id')
                for line in sorted_lines:
                    # Use IDs for the key to ensure reliable grouping
                    # Include lot_name in case lot_id is not yet set
                    key = (
                        line.lot_id.id, 
                        line.lot_name,
                        line.location_id.id, 
                        line.location_dest_id.id, 
                        line.package_id.id, 
                        line.result_package_id.id, 
                        line.owner_id.id, 
                        line.product_id.id
                    )
                    
                    if key in lines_by_key:
                        target_line = lines_by_key[key]
                        # print(f"DEBUG MERGE: Merging line {line.id} into {target_line.id}")
                        
                        # Merge Quantities
                        target_line.quantity += line.quantity
                        
                        # Preserve Traceability Links
                        if line.consume_line_ids:
                            target_line.consume_line_ids |= line.consume_line_ids
                        if line.produce_line_ids:
                            target_line.produce_line_ids |= line.produce_line_ids
                            
                        # If the line is DONE, we cannot unlink it via ORM.
                        # But the user wants it gone from the report (0 qty is not enough).
                        # So we use SQL Delete (Hard Delete).
                        if line.state == 'done':
                            # print(f"DEBUG MERGE: SQL Deleting DONE line {line.id}")
                            self.env.cr.execute("DELETE FROM stock_move_line WHERE id = %s", (line.id,))
                            line.invalidate_recordset()
                        else:
                            # print(f"DEBUG MERGE: Unlinking line {line.id}")
                            line.unlink()
                    else:
                        lines_by_key[key] = line

    @api.onchange('product_qty')
    def _onchange_product_qty(self):
        # Merge finished move lines if quantity changes
        self._merge_finished_move_lines()

    @api.onchange('bom_id')
    def _onchange_bom_id(self):
        super()._onchange_bom_id()
        if self.bom_id and self.bom_id.packaging_id:
            self.packaging_id = self.bom_id.packaging_id
            self.packaging_qty = self.bom_id.packaging_qty
            # Trigger qty calculation (handled by compute)
            # self._onchange_packaging_qty()