from rest_framework.mixins import ListModelMixin, DestroyModelMixin, CreateModelMixin, RetrieveModelMixin
from rest_framework.viewsets import GenericViewSet
from rest_framework.response import Response
from apps.inm.models import FIFO, FIFOItem, FIFOItemProduct, IProduct, WareHouse
from apps.inm.services import InmService
from apps.mtm.models import Material
from apps.sam.models import Sale, SaleProduct
from apps.sam.serializers_sale import SaleCreateSerializer, SaleListSerializer, SaleProductCreateSerializer, SaleProductListSerializer
from rest_framework import exceptions
from django.db import transaction
from rest_framework.decorators import action
from django.utils import timezone

from apps.system.mixins import CreateUpdateModelAMixin
from rest_framework import serializers
from django.db.models import Count

from utils.tools import ranstr

class SaleViewSet(CreateUpdateModelAMixin, ListModelMixin, RetrieveModelMixin, CreateModelMixin, DestroyModelMixin, GenericViewSet):
    """
    销售记录
    """
    perms_map = {'get': '*', 'post':'sale_create', 'delete':'sale_delete'}
    queryset = Sale.objects.select_related('customer', 'order', 'product', 'order__contract').all()
    serializer_class = SaleListSerializer
    search_fields = ['customer__name', 'order__number']
    filterset_fields = ['product', 'order', 'customer']
    ordering_fields = ['create_time']
    ordering = ['-create_time']

    def get_serializer_class(self):
        if self.action == 'create':
            return SaleCreateSerializer
        elif self.action == 'retrieve':
            return SaleListSerializer
        return super().get_serializer_class()
    
    def destroy(self, request, *args, **kwargs):
        obj = self.get_object()
        if obj.is_audited:
            raise exceptions.APIException('该销售记录已审核,不可删除')
        obj.delete()
        IProduct.objects.filter(sale_iproduct__sale=obj).update()

    def create(self, request, *args, **kwargs):
        data = request.data
        serializer = SaleCreateSerializer(data=data)
        serializer.is_valid(raise_exception=True)
        vdata = serializer.validated_data
        with transaction.atomic():
            iproducts = vdata.pop('iproducts')
            vdata['count'] = len(iproducts)
            if vdata['count'] + vdata['order'].delivered_count > vdata['order'].count:
                raise exceptions.APIException('超过订单所需数量')
            sale = Sale.objects.create(**vdata)
            i_l = []
            for i in iproducts:
                i.state = IProduct.SALE_LOCK
                i.save()
                i_d ={}
                i_d['sale'] = sale
                i_d['number'] = i.number
                i_d['iproduct'] = i
                i_l.append(SaleProduct(**i_d))
            SaleProduct.objects.bulk_create(i_l)
        return Response()

    @action(methods=['post'], detail=True, perms_map={'post':'sale_audit'}, serializer_class=serializers.Serializer)
    @transaction.atomic
    def audit(self, request, pk=None):
        """
        审核
        """
        obj = self.get_object()
        if obj.is_audited:
            raise exceptions.APIException('已审核通过')
        if obj.order:
            if obj.count + obj.order.delivered_count > obj.order.count:
                raise exceptions.APIException('超过订单所需数量')
        # 创建出库记录
        fifo = FIFO()
        fifo.sale = obj
        fifo.type = FIFO.FIFO_TYPE_SALE_OUT
        fifo.is_audited = False
        fifo.auditor = request.user
        fifo.inout_date = timezone.now()
        fifo.create_by = request.user
        fifo.number = 'CK' + ranstr(7)
        fifo.save()
        # 创建出库条目
        # ips = IProduct.objects.filter(sale_iproduct__sale=obj)
        # items = ips.values('warehouse', 'material', 'batch').annotate(total=Count('id'))
        # for i in items:
        #     warehouse = WareHouse.objects.get(id=i['warehouse'])
        #     material = Material.objects.get(id=i['material'])
        #     fifoitem = FIFOItem()
        #     fifoitem.need_test = False
        #     fifoitem.warehouse = warehouse
        #     fifoitem.material = material
        #     fifoitem.count = i['total']
        #     fifoitem.batch = i['batch']
        #     fifoitem.fifo = fifo
        #     fifoitem.save()
        #     items_p = ips.filter(warehouse=warehouse, batch=i['batch'])
        #     ipxs = []
        #     for i in items_p:       
        #         # 创建出库明细半成品
        #         ip = {}
        #         ip['fifoitem'] = fifoitem
        #         ip['number'] = i.number
        #         ip['material'] = i.material
        #         ip['iproduct'] = i
        #         ipxs.append(FIFOItemProduct(**ip))
        #     FIFOItemProduct.objects.bulk_create(ipxs)

        # 更新动态产品表情况
        # from apps.wpm.models import WProduct
        # WProduct.objects.filter(iproduct_wproduct__sale_iproduct__sale=obj).update(
        #     act_state=WProduct.WPR_ACT_STATE_SELLED)
        # 更新库存
        # InmService.update_inm(fifo)
        # 变更销售提货审核状态
        obj.is_audited = True
        obj.save()
        # 变更订单状态
        # if obj.order:
        #     order = obj.order
        #     order.delivered_count = order.delivered_count + obj.count
        #     order.save()
        return Response()



class SaleProductViewSet(ListModelMixin, DestroyModelMixin, CreateModelMixin, GenericViewSet):
    """
    销售记录关联产品
    """
    perms_map = {'get': '*', 'post':'sale_update', 'delete':'sale_delete'}
    queryset = SaleProduct.objects.select_related('iproduct', 'iproduct__material', 'iproduct__warehouse').all()
    serializer_class = SaleProductListSerializer
    search_fields = []
    filterset_fields = ['sale', 'iproduct']
    ordering_fields = ['create_time']
    ordering = ['id']

    def get_serializer_class(self):
        if self.action == 'create':
            return SaleProductCreateSerializer
        return super().get_serializer_class()
    
    def destroy(self, request, *args, **kwargs):
        obj = self.get_object()
        sale = obj.sale
        if sale.is_audited:
            raise exceptions.APIException('该销售记录已审核,不可删除产品')
        obj.delete()
        sale.count = SaleProduct.objects.filter(sale=obj.sale).count()
        sale.save()
        return Response()