from django.shortcuts import render
from numpy import delete
from rest_framework.viewsets import ModelViewSet
from rest_framework.mixins import CreateModelMixin, DestroyModelMixin, ListModelMixin, RetrieveModelMixin
from rest_framework.viewsets import GenericViewSet
from apps.pum.models import PuOrder, PuOrderItem, Vendor
from apps.pum.serializers import PuOrderCreateUpdateSerializer, PuOrderItemCreateSerializer, PuOrderItemSerializer, PuOrderItemUpdateSerializer, PuOrderSerializer, VendorSerializer
from apps.system.mixins import CreateUpdateModelAMixin, OptimizationMixin
from rest_framework.exceptions import APIException, ValidationError
from rest_framework.decorators import action
from rest_framework import serializers
from rest_framework.response import Response
from rest_framework import status
# Create your views here.
class VendorViewSet(CreateUpdateModelAMixin, ModelViewSet):
    """
    供应商-增删改查
    """
    perms_map = {'get': '*', 'post': 'vendor_create',
                 'put': 'vendor_update', 'delete': 'vendor_delete'}
    queryset = Vendor.objects.all()
    serializer_class = VendorSerializer
    search_fields = ['name', 'contact']
    filterset_fields = []
    ordering_fields = ['create_time']
    ordering = ['-create_time']


class PuOrderViewSet(CreateUpdateModelAMixin, ModelViewSet):
    """
    采购订单-增删改查
    """
    perms_map = {'get': '*', 'post': 'puorder_create',
                 'put': 'puorder_update', 'delete': 'puorder_delete'}
    queryset = PuOrder.objects.select_related('vendor').\
        prefetch_related('item_pu_order').all()
    serializer_class = PuOrderSerializer
    search_fields = ['number', 'vendor__name']
    filterset_fields = ['vendor']
    ordering = ['-create_time']

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

    def update(self, request, *args, **kwargs):
        obj = self.get_object()
        if obj.is_audited:
            raise ValidationError('该采购订单已审核')
        return super().update(request, *args, **kwargs)
    
    def destroy(self, request, *args, **kwargs):
        obj = self.get_object()
        if obj.is_audited:
            raise ValidationError('该采购订单已审核')
        return super().destroy(request, *args, **kwargs)

    @action(methods=['post'], detail=True, perms_map={'post':'puorder_audit'}, 
        serializer_class=serializers.Serializer)
    def audit(self, request, pk=None):
        obj = self.get_object()
        if obj.item_pu_order.exists() and not obj.is_audited:
            obj.is_audited = True
            obj.update_by = request.user
            obj.save()
            return Response()
        return Response('订单状态有误', status=status.HTTP_400_BAD_REQUEST)

class PuOrderItemViewSet(CreateModelMixin, ListModelMixin, DestroyModelMixin,  RetrieveModelMixin, GenericViewSet):
    """
    采购订单条目
    """
    perms_map = {'get': '*', 'post': 'puorder_update',
                 'put': 'puorder_update', 'delete': 'puorder_update'}
    queryset = PuOrderItem.objects.select_related('material').all()
    serializer_class = PuOrderItemSerializer
    filterset_fields = ['pu_order', 'material']
    ordering = ['-create_time']

    def get_serializer_class(self):
        if self.action == 'create':
            return PuOrderItemCreateSerializer
        elif self.action == 'update':
            return PuOrderItemUpdateSerializer
        return super().get_serializer_class()

    def destroy(self, request, *args, **kwargs):
        obj = self.get_object()
        if obj.pu_order.is_audited:
            raise ValidationError('所属采购已审核')
        return super().destroy(request, *args, **kwargs)