# 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 Column, Window
from sql.aggregate import Max
from sql.conditionals import Coalesce
from sql.functions import LastValue

from trytond.model import ModelSQL, ModelView, convert_from, fields
from trytond.modules.product import round_price
from trytond.pool import Pool, PoolMeta
from trytond.tools import timezone as tz
from trytond.transaction import Transaction


class Product(metaclass=PoolMeta):
    __name__ = 'product.product'

    def get_multivalue(self, name, **pattern):
        pool = Pool()
        Company = pool.get('company.company')
        context = Transaction().context
        if (name == 'cost_price'
                and context.get('_datetime')
                and self.type in ['goods', 'assets']):
            datetime = context['_datetime']
            company = pattern.get(
                'company', Transaction().context.get('company'))
            if company is not None and company >= 0:
                company = Company(company)
                if company.timezone:
                    timezone = tz.ZoneInfo(company.timezone)
                    try:
                        datetime = (
                            datetime.replace(tzinfo=tz.UTC).astimezone(
                                timezone))
                    except OverflowError:
                        pass
            cost_price = self.get_cost_price_at(datetime.date(), **pattern)
            if cost_price is not None:
                return cost_price
        return super().get_multivalue(name, **pattern)

    def get_cost_price_at(self, date, **pattern):
        pool = Pool()
        CostHistory = pool.get('product.product.cost_history')
        company = pattern.get(
            'company', Transaction().context.get('company'))
        with Transaction().set_context(company=company):
            records = CostHistory.search([
                    ('date', '<=', date),
                    ('product', '=', self.id),
                    ], limit=1, order=[('date', 'DESC')])
        if records:
            record, = records
            return round_price(record.cost_price)


class CostPrice(metaclass=PoolMeta):
    __name__ = 'product.cost_price'
    _history = True


class ProductCostHistory(ModelSQL, ModelView):
    __name__ = 'product.product.cost_history'
    product = fields.Many2One('product.product', "Product")
    date = fields.Date('Date')
    cost_price = fields.Numeric('Cost Price')

    @classmethod
    def __setup__(cls):
        super().__setup__()
        cls._order.insert(0, ('date', 'DESC'))

    @classmethod
    def table_query(cls):
        pool = Pool()
        Move = pool.get('stock.move')
        Product = pool.get('product.product')
        Template = pool.get('product.template')
        CostPrice = pool.get('product.cost_price')
        User = pool.get('res.user')
        move = Move.__table__()
        product = Product.__table__()
        template = Template.__table__()
        history = CostPrice.__table_history__()
        transaction = Transaction()
        user = User(transaction.user)

        tables, clause = Move.search_domain([
                ('cost_price', '!=', None),
                ('state', '=', 'done'),
                Product._domain_moves_cost(),
                ['OR',
                    Product._domain_in_moves_cost(),
                    Product._domain_out_moves_cost(),
                    ],
                ], tables={
                None: (move, None),
                })

        cost_price = Coalesce(move.product_cost_price, move.cost_price)
        window = Window(
            [move.effective_date, move.product],
            frame='ROWS', start=None, end=None,
            order_by=[move.write_date.asc, move.id.asc])
        cost_price = LastValue(cost_price, window=window)

        move_history = convert_from(None, tables, type_='INNER').select(
            (move.id * 2).as_('id'),
            move.effective_date.as_('date'),
            move.product.as_('product'),
            cost_price.as_('cost_price'),
            where=clause)
        query = move_history.select(
            Max(move_history.id).as_('id'),
            move_history.date.as_('date'),
            move_history.product.as_('product'),
            Max(move_history.cost_price).as_('cost_price'),
            group_by=[move_history.date, move_history.product])

        if user.company:
            timezone = user.company.timezone
        else:
            timezone = None
        price_datetime = Coalesce(history.write_date, history.create_date)
        price_date = cls.date.sql_cast(price_datetime, timezone=timezone)
        window = Window(
            [price_date, history.product],
            frame='ROWS', start=None, end=None,
            order_by=[price_datetime.asc])
        cost_price = LastValue(history.cost_price, window=window)

        price_history = (history
            .join(product, condition=history.product == product.id)
            .join(template, condition=product.template == template.id)
            .select(
                (Column(history, '__id') * 2 + 1).as_('id'),
                price_date.as_('date'),
                history.product.as_('product'),
                cost_price.as_('cost_price'),
                where=~template.type.in_(['goods', 'assets'])
                & cls._non_moves_clause(history, user)))

        query |= price_history.select(
            Max(price_history.id).as_('id'),
            price_history.date.as_('date'),
            price_history.product.as_('product'),
            Max(price_history.cost_price).as_('cost_price'),
            group_by=[price_history.date, price_history.product])
        return query

    @classmethod
    def _non_moves_clause(cls, history_table, user):
        company_id = user.company.id if user.company else None
        return history_table.company == company_id

    def get_rec_name(self, name):
        return Pool().get('ir.lang').get().strftime(self.date)