from rest_framework import status

from rest_framework.response import Response

from snippets.models import Snippet

from snippets.serializers import SnippetSerizlizer

from rest_framework.decorators import APIView  # 导入APIView

from django.http.response import Http404

# 定义 类视图 继承APIView

# 内部定义对应的请求方法，会根据前端的请求类型做不同的操作

class SnippetList(APIView):

    # 定义get方法

    def get(self, request, format=None):

        snippets = Snippet.objects.all()

        serializer = SnippetSerizlizer(snippets, many=True)

        return Response(serializer.data)

    # 定义post方法

    def post(self, request, format=None):

        serializer = SnippetSerizlizer(data=request.data)

        if serializer.is_valid():

            serializer.save()

            return Response(serializer.data, status=status.HTTP_201_CREATED)

        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

class SnippetDEtail(APIView):

    def get_object(self, pk):

        try:

            snippet = Snippet.objects.get(pk=pk)

            return snippet

        except Snippet.DoesNotExist:  # 如果查询不到传入的pk字段，则执行以下代码

            return Http404

    def get(self, request, pk, format=None):

        snippet = self.get_object(pk)

        serializer = SnippetSerizlizer(snippet)

        return Response(serializer.data)

    # 定义put方法

    def put(self, request, pk, format=None):

        snippet = self.get_object(pk)

        serializer = SnippetSerizlizer(snippet, data=request.data)

        if serializer.is_valid():

            serializer.save()

            return Response(serializer.data)

        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)

    # 定义删除方法

    def delete(self, request, pk, format=None):

        snippet = self.get_object(pk)

        snippet.delete()

        return Response(status=status.HTTP_204_NO_CONTENT)

urlpatterns = [

    path('snippets/',views.SnippetList.as_view()),

    path('snippets/<int:pk>/',views.SnippetDEtail.as_view())

]