class CreatePurchaseRequestQuotationAskSuppliers(ModelView):
    'Create Purchase Request Quotation Ask Suppliers'
    __name__ = 'purchase.request.create_quotation.ask_suppliers'

    requests = fields.Many2Many('purchase.request', None, None, 'Requests',
                    required=True, readonly=True)
    suppliers = fields.Many2Many('party.party', None, None, 'Suppliers',
                    required=True)


class CreatePurchaseRequestQuotation(Wizard):
    'Create Purchase Request Quotation'
    __name__ = 'purchase.request.create_quotation'

    start = StateTransition()
    ask_suppliers = StateView(
        'purchase.request.create_quotation.ask_suppliers',
        'purchase_request_quotation.purchase_request_create_quotation_ask_suppliers', [
            Button('Cancel', 'end', 'tryton-cancel'),
            Button('Continue', 'start', 'tryton-go-next', default=True),
            ])

    @classmethod
    def __setup__(cls):
        super(CreatePurchaseRequestQuotation, cls).__setup__()
        cls._error_messages.update({
                'previous_quotation': ('You already made a quotation with '
                    'one of the selected requests: "%(requests)s".'),
                })

    def default_ask_suppliers(self, fields):
        pool = Pool()
        values = {}
        request_quotation_state = []
        Request = pool.get('purchase.request')

        request_ids = Transaction().context['active_ids']
        requests = Request.search([
                    ('id', 'in', request_ids),
                    ('state', 'in', ['draft', 'quotation']),
                    ])
        self.raise_user_warning('previous_quotation', {
                            'requests': ', '.join(r.rec_name
                                for r in requests),
                            })
        values['requests'] = requests
        for request in requests:
            if request.state == 'quotation':
                request_quotation_state.append(request)
            if request.party:
                values['suppliers'].append(request.party)
        if request_quotation_state:
            self.raise_user_warning('previous_quotation', {
                            'requests': ', '.join(r.rec_name
                                for r in request_quotation_state),
                            })
        return values

    def transition_start(self):
        pool = Pool()
        Request = pool.get('purchase.request')
        Quotation = pool.get('purchase.request.quotation')

        new_quotations = []
        request_ids = Transaction().context['active_ids']
        requests = Request.search([
                    ('id', 'in', request_ids),
                    ('state', 'in', ['draft', 'quotation']),
                    ])
        for request in requests:
            new_quotations.append({
                        'company': request.company,
                        'origin': request,
                        'description': request.description,
                        'quantity': request.quantity,
                        'unit': request.uom,
                        'currency': request.currency,
                        'supply_date': (
                            request.supply_date or datetime.date.max),
                        })
        suppliers = []
        for supplier in getattr(self.ask_suppliers, 'suppliers', []):
            suppliers.append({
                    'supplier': supplier,
                    })
        if suppliers:
            quotation_lines = []
            for (nq, s) in product(new_quotations, suppliers):
                merged = {}
                merged.update(nq)
                merged.update(s)
                quotation_lines.append(merged)
            Quotation.save(quotation_lines)

            quotations = sorted(quotation_lines,
                            key=self._group_purchase_request_quotation_key)
            for key, grouped_quotations in groupby(quotations,
                    key=self._group_purchase_request_quotation_key):
                    group = self._new_group(dict(key))
                    group.save()
                    Quotation.write(grouped_quotations, {'group': group.id})

        return 'end'

    def _group_purchase_request_quotation_key(self, quotation):
        return (
            ('company', quotation.company),
            ('supplier', quotation.supplier),
            )

    def _new_group(self, values):
        pool = Pool()
        Group = pool.get('purchase.request.quotation.group')
        return Group(**values)