from rest_framework import viewsets
from article.serializers import ArticleSerializer, CategorySerializer, CategoryDetailSerializer
from article.serializers import TagSerializer, ArticleDetailSerializer, AvatarSerializer
from article.models import Article, Category, Tag, Avatar
from article.permissions import IsAdminUserOrReadOnly
from rest_framework.filters import SearchFilter


class ArticleViewSet(viewsets.ModelViewSet):
    """文章视图集"""
    queryset = Article.objects.all()
    serializer_class = ArticleSerializer
    permission_classes = [IsAdminUserOrReadOnly]
    filter_backends = [SearchFilter, ]

    # http://127.0.0.1:8000/api/article/?author__username=admin&title=第一篇文章
    # filter_fields = ['title', 'author__username',] # 精确查询

    # 下面两种字段都可以使用模糊查询
    search_fields = ('title', 'author__username')

    def perform_create(self, serializer):
        # 在创建文章前，提供了视图集无法自行推断的用户外键字段。
        serializer.save(author=self.request.user)

    def get_serializer_class(self):
        if self.action == 'list':
            return ArticleSerializer
        else:
            return ArticleDetailSerializer


class CategoryViewSet(viewsets.ModelViewSet):
    """分类视图集"""
    queryset = Category.objects.all()
    serializer_class = CategorySerializer
    permission_classes = [IsAdminUserOrReadOnly]
    pagination_class = None  # 不进行翻页

    def get_serializer_class(self):
        if self.action == 'list':
            return CategorySerializer
        else:
            return CategoryDetailSerializer


class TagViewSet(viewsets.ModelViewSet):
    """标签视图集"""
    queryset = Tag.objects.all()
    serializer_class = TagSerializer
    permission_classes = [IsAdminUserOrReadOnly]
    pagination_class = None  # 不进行翻页


class AvatarViewSet(viewsets.ModelViewSet):
    """标题图片视图集"""
    queryset = Avatar.objects.all()
    serializer_class = AvatarSerializer
    permission_classes = [IsAdminUserOrReadOnly]