from odoo import models, api

class StockMove(models.Model):
    _inherit = 'stock.move'

    def _should_bypass_set_qty_producing(self):
        """
        Only bypass if explicitly flagged as manual consumption.
        We rely on the write() method to set this flag and to block resets.
        """
        # Remove sudo() to allow NewId (virtual records) to access their cache.
        # If we use sudo(), it might force a DB read which fails for NewId or returns old data.
        allow_bypass = self.manual_consumption
        
        # NewId Fix: If it's a virtual record (NewId) and has quantity, it's "locked" logic-wise
        # because the user (or auto-fill) has set a value, and we don't want scaling to wipe it.
        # Real IDs are integers. Virtual IDs (NewId) are not.
        if not allow_bypass and self.quantity > 0 and not isinstance(self.id, int):
             allow_bypass = True
             
        if allow_bypass:
            return True
        return super()._should_bypass_set_qty_producing()

    def write(self, vals):
        # 1. Zero-Guard: Block resets to 0 if Locked
        # We ALLOW positive updates so users can manually set consumption.
        # We rely on _should_bypass_set_qty_producing (via manual_consumption=True) 
        # to prevent the System from generating Scaling updates.
        if 'quantity' in vals and vals['quantity'] == 0:
            locked_moves = self.filtered(lambda m: m.manual_consumption)
            if locked_moves and len(locked_moves) == len(self):
                del vals['quantity']

        # 2. Arm the Lock
        if 'quantity' in vals and vals.get('quantity', 0) > 0:
             vals['manual_consumption'] = True
             vals['picked'] = True

        return super().write(vals)

    @api.model_create_multi
    def create(self, vals_list):
        for vals in vals_list:
             # Look at Consumed (quantity) only.
             # If we lock on Demand (product_uom_qty), we block the initial auto-fill.
             consumed = vals.get('quantity', 0)
             
             if consumed > 0:
                 # Lock Immediately if created with a specific consumed quantity
                 vals['manual_consumption'] = True
                 vals['picked'] = True
        return super().create(vals_list)