# Copyright 2015-2017 Akretion (http://www.akretion.com)
# @author Alexis de Lattre <alexis.delattre@akretion.com>
# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).

from odoo import _, api, models
from odoo.exceptions import ValidationError
from odoo.tools import config, float_compare


class StockQuant(models.Model):
    _inherit = "stock.quant"

    @api.constrains("product_id", "quantity")
    def check_negative_qty(self):
        # To provide an option to skip the check when necessary.
        # e.g. mrp_subcontracting_skip_no_negative - passes the context
        # for subcontracting receipts.
        # Also allows negative stock for subcontracting locations as they
        # are expected to have negative stock in certain Odoo 18 workflows.
        if self.env.context.get("skip_negative_qty_check"):
            return
        p = self.env["decimal.precision"].precision_get("Product Unit of Measure")
        check_negative_qty = (
            config["test_enable"] and self.env.context.get("test_stock_no_negative")
        ) or not config["test_enable"]
        if not check_negative_qty:
            return

        for quant in self:
            disallowed_by_product = (
                not quant.product_id.allow_negative_stock
                and not quant.product_id.categ_id.allow_negative_stock
            )
            disallowed_by_location = not quant.location_id.allow_negative_stock
            
            # Allow negative stock for subcontracting locations
            # Check if mrp_subcontracting is installed and location has is_subcontracting_location field
            is_subcontracting_location = False
            if hasattr(quant.location_id, 'is_subcontracting_location'):
                is_subcontracting_location = quant.location_id.is_subcontracting_location
            
            if (
                float_compare(quant.quantity, 0, precision_digits=p) == -1
                and quant.product_id.is_storable
                and quant.location_id.usage in ["internal", "transit"]
                and disallowed_by_product
                and disallowed_by_location
                and not is_subcontracting_location
            ):
                msg_add = ""
                if quant.lot_id:
                    msg_add = _(" lot %(name)s", name=quant.lot_id.display_name)
                raise ValidationError(
                    _(
                        "You cannot validate this stock operation because the "
                        "stock level of the product '{name}'{name_lot} would "
                        "become negative "
                        "({q_quantity}) on the stock location '{complete_name}' "
                        "and negative stock is "
                        "not allowed for this product and/or location."
                    ).format(
                        name=quant.product_id.display_name,
                        name_lot=msg_add,
                        q_quantity=quant.quantity,
                        complete_name=quant.location_id.complete_name,
                    )
                )