# 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 functools import wraps

from trytond.model import ModelView, Workflow, fields
from trytond.pool import Pool, PoolMeta
from trytond.tools import grouped_slice
from trytond.transaction import Transaction, without_check_access


class Request(metaclass=PoolMeta):
    __name__ = 'purchase.request'

    sale_lines = fields.One2Many(
        'sale.line', 'purchase_request', "Sale Lines", readonly=True)

    @classmethod
    def _get_origin(cls):
        return super()._get_origin() | {'sale.sale'}

    @classmethod
    def copy(cls, requests, default=None):
        default = default.copy() if default is not None else {}
        default.setdefault('sale_lines')
        return super().copy(requests, default=default)

    @classmethod
    def delete(cls, requests):
        pool = Pool()
        Sale = pool.get('sale.sale')
        SaleLine = pool.get('sale.line')
        transaction = Transaction()
        context = transaction.context

        with without_check_access():
            reqs = cls.browse(requests)
            sales = set(r.origin for r in reqs if isinstance(r.origin, Sale))
            sale_lines = [l for r in reqs for l in r.sale_lines]
            if sale_lines:
                SaleLine.write(sale_lines, {
                        'purchase_request': None,
                        })

        super().delete(requests)

        if sales:
            with transaction.set_context(
                    queue_batch=context.get('queue_batch', True)):
                Sale.__queue__.process(sales)


def process_sale_supply(func):
    @wraps(func)
    def wrapper(cls, purchases):
        pool = Pool()
        Request = pool.get('purchase.request')
        Sale = pool.get('sale.sale')
        transaction = Transaction()
        context = transaction.context

        sales = set()
        with without_check_access():
            for sub_purchases in grouped_slice(purchases):
                ids = [x.id for x in sub_purchases]
                requests = Request.search([
                        ('purchase_line.purchase.id', 'in', ids),
                        ('origin', 'like', 'sale.sale,%'),
                        ])
                sales.update(r.origin.id for r in requests)
        func(cls, purchases)
        if sales:
            with transaction.set_context(
                    queue_batch=context.get('queue_batch', True)):
                Sale.__queue__.process(sales)
    return wrapper


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

    @classmethod
    @ModelView.button
    @process_sale_supply
    def process(cls, purchases):
        super(Purchase, cls).process(purchases)

    @classmethod
    @ModelView.button
    @Workflow.transition('cancelled')
    @process_sale_supply
    def cancel(cls, purchases):
        super(Purchase, cls).cancel(purchases)


class HandlePurchaseCancellationException(metaclass=PoolMeta):
    __name__ = 'purchase.request.handle.purchase.cancellation'

    def transition_cancel_request(self):
        pool = Pool()
        SaleLine = pool.get('sale.line')
        Move = pool.get('stock.move')
        Shipment = pool.get('stock.shipment.out')

        next_state = super(HandlePurchaseCancellationException,
            self).transition_cancel_request()
        moves = []
        shipments = set()
        for sub_ids in grouped_slice(list(map(int, self.records))):
            sale_lines = SaleLine.search([
                    ('purchase_request', 'in', sub_ids),
                    ])
            for sale_line in sale_lines:
                moves.extend(sale_line.moves)
                for shipment in sale_line.sale.shipments:
                    if shipment.state in ['draft', 'waiting']:
                        shipments.add(shipment)
        if moves:
            shipments_waiting = [s for s in shipments if s.state == 'waiting']
            Shipment.draft(shipments)  # clear inventory moves
            Move.cancel(moves)
            Shipment.wait([
                    s for s in shipments_waiting
                    if any(m.state != 'cancelled' for m in s.outgoing_moves)])
            Shipment.cancel([
                    s for s in shipments_waiting
                    if all(m.state == 'cancelled' for m in s.outgoing_moves)])
        return next_state