# 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 trytond.pool import Pool, PoolMeta
from trytond.model import ModelView, ModelSQL, fields
from trytond.pyson import Eval

from trytond.exceptions import UserError

class Purchase(metaclass=PoolMeta):
    'Purchase Analytic Operation'
    __name__ = 'purchase.purchase'

    _states = {
        'readonly': Eval('state') != 'draft',
        }

    account_analytic = fields.Many2One('analytic_account.account', 'Analytic Account', required=True,
                                       domain=[('type', '=', 'normal')],
                                       states=_states)
class PurchaseLine(metaclass=PoolMeta):
    'Purchase Line Analytic Operation'
    __name__ =  'purchase.line'

    @fields.depends('product', 'unit', 'purchase',
        '_parent_purchase.party', '_parent_purchase.invoice_party',
        '_parent_purchase.account_analytic', 'product_supplier',
        'analytic_accounts', methods=['compute_taxes', 'compute_unit_price',
                                     '_get_product_supplier_pattern'])
    def on_change_product(self):
        if not self.product:
            return

        party = None
        if self.purchase:
            party = self.purchase.invoice_party or self.purchase.party

        # Set taxes before unit_price to have taxes in context of purchase
        # price
        self.taxes = self.compute_taxes(party)

        category = self.product.purchase_uom.category
        if not self.unit or self.unit.category != category:
            self.unit = self.product.purchase_uom

        product_suppliers = list(self.product.product_suppliers_used(
                **self._get_product_supplier_pattern()))
        if len(product_suppliers) == 1:
            self.product_supplier, = product_suppliers
        elif (self.product_supplier
                and self.product_supplier not in product_suppliers):
            self.product_supplier = None

        self.unit_price = self.compute_unit_price()

        self.type = 'line'
        self.amount = self.on_change_with_amount()

        self.analytic_accounts = tuple()
        try:
            self.analytic_accounts += ({'root': self.purchase.account_analytic.root,
                                        'account': self.purchase.account_analytic},) 
        except:
            pass