from django.db import transaction
from rest_framework import exceptions, serializers
from rest_framework.mixins import CreateModelMixin, DestroyModelMixin, ListModelMixin, RetrieveModelMixin
from apps.inm.models import FIFO
from apps.sam.serializers import ContractCreateUpdateSerializer, ContractSerializer, CustomerCreateUpdateSerializer, CustomerSerializer, OrderCreateUpdateSerializer, OrderSerializer, SaleCreateSerializer, SaleListSerializer, SaleProductCreateSerializer, SaleProductListSerializer, SaleProductMtestSerializer
from apps.sam.models import Contract, Customer, Order, Sale, SaleProduct
from rest_framework.viewsets import GenericViewSet, ModelViewSet
from apps.system.mixins import CreateUpdateCustomMixin
from django.shortcuts import render
from rest_framework.decorators import action
from django.db.models import F
from rest_framework.response import Response
from django.utils import timezone
# Create your views here.
class CustomerViewSet(CreateUpdateCustomMixin, ModelViewSet):
    """
    客户-增删改查
    """
    perms_map = {'*': '*'}
    queryset = Customer.objects.all()
    serializer_class = CustomerSerializer
    search_fields = ['name', 'contact']
    filterset_fields = []
    ordering_fields = ['create_time']
    ordering = ['-create_time']

    def get_serializer_class(self):
        if self.action in ['create', 'update']:
            return CustomerCreateUpdateSerializer
        return CustomerSerializer


class ContractViewSet(CreateUpdateCustomMixin, ModelViewSet):
    """
    合同-增删改查
    """
    perms_map = {'*': '*'}
    queryset = Contract.objects.select_related('customer').all()
    serializer_class = ContractSerializer
    search_fields = ['name']
    filterset_fields = []
    ordering_fields = ['create_time']
    ordering = ['-create_time']

    def get_serializer_class(self):
        if self.action in ['create', 'update']:
            return ContractCreateUpdateSerializer
        return ContractSerializer

class OrderViewSet(CreateUpdateCustomMixin, ModelViewSet):
    """
    订单-增删改查
    """
    perms_map = {'*': '*'}
    queryset = Order.objects.select_related('contract', 'customer').all()
    serializer_class = OrderSerializer
    search_fields = ['number', 'product']
    filterset_fields = ['product', 'contract', 'customer']
    ordering_fields = ['create_time']
    ordering = ['-create_time']

    def get_serializer_class(self):
        if self.action in ['create', 'update']:
            return OrderCreateUpdateSerializer
        return super().get_serializer_class()

    @action(methods=['get'], detail=False, perms_map={'get':'*'})
    def toplan(self, request, pk=None):
        queryset = Order.objects.filter(count__gt=F('planed_count')).order_by('-id')
        page = self.paginate_queryset(queryset)
        if page is not None:
            serializer = self.get_serializer(page, many=True)
            return self.get_paginated_response(serializer.data)
        serializer = self.get_serializer(queryset, many=True)
        return Response(serializer.data)


class SaleViewSet(CreateUpdateCustomMixin, ListModelMixin, RetrieveModelMixin, CreateModelMixin, GenericViewSet):
    """
    销售记录
    """
    perms_map = {'*': '*'}
    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 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)
            sale = Sale.objects.create(**vdata)
            i_l = []
            for i in iproducts:
                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':'*'}, 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')
        # 创建出库记录
        fifo = FIFO()
        fifo.type = FIFO.FIFO_TYPE_SALE_OUT
        fifo.is_audited = True
        fifo.auditor = request.user
        fifo.inout_date = timezone.now()
        fifo.save()
        # 出库条目
        spds = SaleProduct.objects.filter(sale=obj)
        for i in spds:
            if i.is_mtested and i.is_mtestok:
                pass
            else:
                raise exceptions.APIException('存在未军检产品')
        # 更新库存
        return Response()

class SaleProductViewSet(ListModelMixin, DestroyModelMixin, CreateModelMixin, GenericViewSet):
    """
    销售记录关联产品
    """
    perms_map = {'*': '*'}
    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()
        obj.sale.count = SaleProduct.objects.filter(sale=obj.sale).count()
        obj.sale.save()
        obj.delete()
        return Response()
    
    @action(methods=['post'], detail=True, perms_map={'post':'*'}, serializer_class=SaleProductMtestSerializer)
    def mtest(self, request, pk=None):
        """
        军检
        """
        obj = self.get_object()
        if obj.is_mtested:
            raise exceptions.APIException('已进行军检')
        obj.remark = request.data.get('remark', None)
        obj.is_mtestok = request.data.get('is_mtestok')
        obj.save()
        return Response()