# This file is part of Tryton.  The COPYRIGHT file at the top level of
# this repository contains the full copyright notices and license terms.


from sql import Null
from sql.conditionals import Greatest, Least
from sql.operators import Equal

from trytond.model import Exclude, ModelSQL, ModelView, Unique, fields
from trytond.pool import Pool
from trytond.pyson import Eval, If
from trytond.transaction import Transaction


class OrderPoint(ModelSQL, ModelView):
    """
    Provide a way to define a supply policy for each
    product on each locations. Order points on warehouse are
    considered by the supply scheduler to generate purchase requests.
    """
    __name__ = 'stock.order_point'
    product = fields.Many2One(
        'product.product', "Product", required=True,
        domain=[
            ('type', '=', 'goods'),
            ('consumable', '=', False),
            ('purchasable', 'in',
                If(Eval('type') == 'purchase',
                    [True],
                    [True, False])),
            ],
        context={
            'company': Eval('company', -1),
            },
        depends={'company'})
    location = fields.Many2One(
        'stock.location', "Location", required=True,
        domain=[
            If(Eval('type') == 'internal',
                ('type', '=', 'storage'),
                ('type', '=', 'warehouse')),
            ])
    provisioning_location = fields.Many2One(
        'stock.location', 'Provisioning Location',
        domain=[('type', 'in', ['storage', 'view'])],
        states={
            'invisible': Eval('type') != 'internal',
            'required': ((Eval('type') == 'internal')
                & (Eval('min_quantity', None) != None)),  # noqa: E711
        })
    overflowing_location = fields.Many2One(
        'stock.location', 'Overflowing Location',
        domain=[('type', 'in', ['storage', 'view'])],
        states={
            'invisible': Eval('type') != 'internal',
            'required': ((Eval('type') == 'internal')
                & (Eval('max_quantity', None) != None)),  # noqa: E711
            })
    type = fields.Selection(
        [('internal', 'Internal'),
         ('purchase', 'Purchase')],
        "Type", required=True)
    min_quantity = fields.Float(
        "Minimal Quantity", digits='unit',
        states={
            # required for purchase and production types
            'required': Eval('type') != 'internal',
            },
        domain=['OR',
            ('min_quantity', '=', None),
            ('min_quantity', '<=', Eval('target_quantity', 0)),
            ])
    target_quantity = fields.Float(
        "Target Quantity", digits='unit', required=True,
        domain=[
            ['OR',
                ('min_quantity', '=', None),
                ('target_quantity', '>=', Eval('min_quantity', 0)),
                ],
            ['OR',
                ('max_quantity', '=', None),
                ('target_quantity', '<=', Eval('max_quantity', 0)),
                ],
            ])
    max_quantity = fields.Float(
        "Maximal Quantity", digits='unit',
        states={
            'invisible': Eval('type') != 'internal',
            },
        domain=['OR',
            ('max_quantity', '=', None),
            ('max_quantity', '>=', Eval('target_quantity', 0)),
            ])
    company = fields.Many2One('company.company', 'Company', required=True)
    unit = fields.Function(fields.Many2One('product.uom', 'Unit'), 'get_unit')

    @classmethod
    def __setup__(cls):
        super().__setup__()

        t = cls.__table__()
        for location_name in [
                'provisioning_location', 'overflowing_location']:
            column = getattr(t, location_name)
            cls._sql_constraints.append(
                ('concurrent_%s_internal' % location_name,
                    Exclude(t,
                        (t.product, Equal),
                        (Greatest(t.location, column), Equal),
                        (Least(t.location, column), Equal),
                        (t.company, Equal),
                        where=t.type == 'internal'),
                    'stock_supply.msg_order_point_concurrent_%s_internal' %
                    location_name))
        cls._sql_constraints.append(
            ('product_location_purchase_unique',
                Unique(t, t.product, t.location, t.company),
                'stock_supply.msg_order_point_unique'))

    @classmethod
    def __register__(cls, module):
        table = cls.__table__()
        table_h = cls.__table_handler__(module)
        cursor = Transaction().connection.cursor()

        super().__register__(module)

        # Migration from 7.2: merge warehouse_location and storage_location
        if table_h.column_exist('warehouse_location'):
            cursor.execute(*table.update(
                    [table.location],
                    [table.warehouse_location],
                    where=(table.location == Null)
                    & (table.warehouse_location != Null)))
            table_h.drop_column('warehouse_location')
        if table_h.column_exist('storage_location'):
            cursor.execute(*table.update(
                    [table.location],
                    [table.storage_location],
                    where=(table.location == Null)
                    & (table.storage_location != Null)))
            table_h.drop_column('storage_location')

    @staticmethod
    def default_type():
        return "purchase"

    @fields.depends('type', 'location')
    def on_change_type(self):
        if self.type == 'internal' and self.location:
            if self.location.type != 'storage':
                self.location = None
        elif self.location:
            if self.location.type != 'warehouse':
                self.location = None

    @classmethod
    def default_location(cls):
        return Pool().get('stock.location').get_default_warehouse()

    @fields.depends('product', '_parent_product.default_uom')
    def on_change_product(self):
        self.unit = None
        if self.product:
            self.unit = self.product.default_uom

    def get_unit(self, name):
        return self.product.default_uom.id

    @property
    def warehouse_location(self):
        if self.type == 'purchase':
            return self.location

    @property
    def storage_location(self):
        if self.type == 'internal':
            return self.location

    def get_rec_name(self, name):
        return "%s @ %s" % (self.product.name, self.location.name)

    @classmethod
    def search_rec_name(cls, name, clause):
        _, operator, value = clause
        if operator.startswith('!') or operator.startswith('not '):
            bool_op = 'AND'
        else:
            bool_op = 'OR'
        return [bool_op,
            ('location.rec_name', *clause[1:]),
            ('product.rec_name', *clause[1:]),
            ]

    @staticmethod
    def default_company():
        return Transaction().context.get('company')

    @classmethod
    def supply_stock(cls):
        pool = Pool()
        StockSupply = pool.get('stock.supply', type='wizard')
        session_id, _, _ = StockSupply.create()
        StockSupply.execute(session_id, {}, 'create_')
        StockSupply.delete(session_id)