# 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 datetime import date

from trytond.model import fields, ModelSQL, ModelView
from trytond.pool import PoolMeta, Pool
from trytond.i18n import gettext
from trytond.pyson import Eval
from trytond.exceptions import UserError
from .schedule import PAYMENT_METHOD


class ContractProductLine(metaclass=PoolMeta):
    __name__ = 'sale.contract.product_line'
    shift_payment_method = fields.Selection(PAYMENT_METHOD,
        'Shift Payment Method', states={'invisible': ~Eval('require_plan', False)})
    location = fields.Many2One('surveillance.location', 'Location',
        states={'invisible': ~Eval('require_plan', False)})
    require_plan = fields.Boolean('Require Plan',
        help='Check this option if product require surveillance plan')
    positions_plan = fields.One2Many('sale.contract.product.position',
        'product_line', 'Products Plan',
        states={'invisible': ~Eval('require_plan', False)},
        context={
            'location': Eval('location', -1)
        })


class SaleContract(metaclass=PoolMeta):
    __name__ = 'sale.contract'

    @classmethod
    def _get_origin(cls):
        return super(SaleContract, cls)._get_origin() + ['crm.opportunity']

    @classmethod
    def confirm(cls, contracts):
        super(SaleContract, cls).confirm(contracts)
        for contract in contracts:
            contract.create_plan()

    def create_plan(self):
        pool = Pool()
        Plan = pool.get('surveillance.plan')
        plans = Plan.search([
            ('customer', '=', self.party.id),
        ])
        if not plans:
            plan, = Plan.create([{
                'customer': self.party.id,
                'company': self.company.id,
                'state': 'draft',
            }])
        else:
            plan = plans[0]

        to_add = []
        for li in self.product_lines:
            if not li.require_plan:
                continue
            if not li.location:
                raise UserError(gettext('surveillance.msg_missing_location'))
            to_add.append({
                'location': li.location.id,
                'contract': li.contract.id,
                'hired_service': li.id,
                'start_date': li.start_date,
                'end_date': li.end_date,
                'shift_payment_method': li.shift_payment_method,
                'state': 'preoperative',
                'comment': li.description,
            })
        if to_add:
            Plan.write([plan], {
                'lines': [('create', to_add)]
            })


class SaleOpportunity(metaclass=PoolMeta):
    __name__ = "crm.opportunity"
    contracts = fields.One2Many('sale.contract', 'origin', 'Contract')

    @classmethod
    def convert(cls, opportunities):
        # Contract = Pool().get('sale.contract')
        contracts = [o.create_contract() for o in opportunities if not o.contracts]

    def create_contract(self):
        '''
        Create a sale contract for the opportunity and return the contract
        '''
        contract = self.get_contract_opportunity()
        contract_lines = []
        for line in self.lines:
            contract_lines.append(self.get_contract_line(line))
        contract.product_lines = contract_lines
        contract.save()
        return contract

    def get_contract_opportunity(self):
        '''
        Return contract for an opportunity
        '''
        SaleContract = Pool().get('sale.contract')
        contract = {
            'description': self.description,
            'party': self.party,
            'payment_term': self.payment_term,
            'company': self.company,
            'currency': self.company.currency,
            'comment': self.comment,
            'contract_date': date.today(),
            'start_date': date.today(),
            'invoice_method': 'standard',
            'origin': str(self),
        }
        contract, = SaleContract.create([contract])
        return contract

    def get_contract_line(self, line):
        value = {
            'product': line.product.id,
            'unit_price': line.unit_price or 0,
            'description': line.product.rec_name,
            'type': 'line',
            # 'quantity': line.quantity,
        }
        return value


class ContractProductPosition(ModelSQL, ModelView):
    "Contract Product Position"
    __name__ = "sale.contract.product.position"
    product_line = fields.Many2One('sale.contract.product_line', 'Product Line',
        required=True, ondelete='CASCADE')
    position = fields.Many2One('surveillance.location.position', 'Position',
        domain=[
            ('location', '=', Eval('_parent_product_line', {}).get('location'))
        ], required=True)