from trytond.pool import Pool, PoolMeta
from trytond.model import (
    ModelSQL, ModelView, Workflow, fields)
from trytond.modules.company.model import set_employee
from trytond.exceptions import UserError

from trytond.wizard import (
    Button, StateAction, StateTransition, StateView, Wizard)


class Subscription(metaclass=PoolMeta):
    __name__ = 'sale.subscription'

    equipments = fields.Many2Many('sale.subscription-optical_equipment.equipment', 'subscription',
                                  'equipment', "Equipments")

    @classmethod
    @ModelView.button
    @Workflow.transition('running')
    @set_employee('run_by')
    def run(cls, subscriptions):
        pool = Pool()
        Line = pool.get('sale.subscription.line')
        lines = []

        pool = Pool()
        Equipments = pool.get('optical_equipment.equipment')

        for subscription in subscriptions:
            if not subscription.next_invoice_date:
                subscription.next_invoice_date = (
                    subscription.compute_next_invoice_date())
            for line in subscription.lines:
                if (line.next_consumption_date is None
                        and not line.consumed_until):
                    line.next_consumption_date = (
                        line.compute_next_consumption_date())
            lines.extend(subscription.lines)
            for equipment in subscription.equipments:
                equipment.state = "contrated"
                equipment.save()
        Line.save(lines)
        cls.save(subscriptions)


class CreateContractInvoice(Wizard):
    "Create Contract Invoice"
    __name__ = 'sale.subscription.create_invoice_contract'

    start = StateView(
    'sale.subscription.create_invoice_contract.start',
    'optical_equipment.create_invoice_contract_start_view_form',[
        Button("Cancel", 'end', 'tryton-cancel'),
        Button("Create", 'create_invoice', 'tryton-ok', default=True),
    ])

    create_invoice = StateAction('account_invoice.act_invoice_form')


    def do_create_invoice(self, action):
        'Create and return an invoice'
        raise UserError(str(dir(action)))
        
        invoice_lines = []
        for line in self.lines:
            invoice_lines.append(line.get_invoice_line())
        invoice_lines = list(chain(*invoice_lines))

        if not invoice_lines:
            return


        invoice = self._get_invoice_sale()
        if getattr(invoice, 'lines', None):
            invoice_lines = list(invoice.lines) + invoice_lines
        invoice.lines = invoice_lines

        return invoice

class CreateContractInvoiceStart(ModelView):
    "Create Subscription Invoice"
    __name__ = 'sale.subscription.create_invoice_contract.start'

    date = fields.Date("Date")

    @classmethod
    def default_date(cls):
        pool = Pool()
        Date = pool.get('ir.date')

        return Date.today()

class SubscriptionEquipment(ModelSQL):
    'Optical Equipment - Subscription'
    __name__ = 'sale.subscription-optical_equipment.equipment'
    
    subscription = fields.Many2One('sale.subscription', 'Subscription', select=True)
    equipment = fields.Many2One('optical_equipment.equipment', 'Equipment', select=True)
    
class Line(metaclass=PoolMeta):
    __name__ = 'sale.subscriptioin.line'