feat(library): add endpoint for listing downloaded books and remove filtering from book list

- Introduced a new `DownloadedBooksListView` to retrieve books downloaded by the current user.
- Updated `urls.py` to include the new endpoint `/books/downloaded/`.
- Removed the `is_downloaded` parameter from the `BookListView` to streamline the book listing process.

apps/library/doc.py

@@ -41,14 +41,6 @@ is_bookmark_param = openapi.Parameter(
     required=False
 )
 
-is_downloaded_param = openapi.Parameter(
-    'is_downloaded',
-    openapi.IN_QUERY,
-    description="Filter books that are downloaded by the current user (set to 'true' to enable)",
-    type=openapi.TYPE_BOOLEAN,
-    required=False
-)
-
 search_param = openapi.Parameter(
     'search',
     openapi.IN_QUERY,
@@ -189,13 +181,14 @@ book_list_swagger = swagger_auto_schema(
     - Middle section collection using the query parameter 'middle'
     - Bottom section collection using the query parameter 'bottom'
     - Bookmarked books using the query parameter 'is_bookmark=true'
-    - Downloaded books using the query parameter 'is_downloaded=true'
 
     You can also search for books by title, summary, or author using the query parameter 'search'.
+    
+    Note: To get downloaded books, use the separate endpoint /books/downloaded/
     """,
     operation_summary="List Books",
     tags=["Library"],
-    manual_parameters=[collection_id_param, middle_param, bottom_param, is_bookmark_param, is_downloaded_param, search_param],
+    manual_parameters=[collection_id_param, middle_param, bottom_param, is_bookmark_param, search_param],
     responses={
         200: books_response,
         401: "Authentication credentials were not provided or are invalid.",

apps/library/urls.py

@@ -6,6 +6,7 @@ from apps.library.views import (
     MiddleBookCollectionListView,
     BookListView,
     BookDetailView,
+    DownloadedBooksListView,
     BookDownloadCreateAPIView,
 )
 
@@ -15,5 +16,6 @@ urlpatterns = [
     path('collections/', MiddleBookCollectionListView.as_view(), name='collection-list'),
     path('books/', BookListView.as_view(), name='book-list'),
     path('books/<int:pk>/', BookDetailView.as_view(), name='book-detail'),
+    path('books/downloaded/', DownloadedBooksListView.as_view(), name='downloaded-books-list'),
     path('books/download/', BookDownloadCreateAPIView.as_view(), name='book-download'),
 ]

apps/library/views.py

@@ -137,18 +137,6 @@ class BookListView(ListAPIView):
             # Filter books by these IDs
             queryset = queryset.filter(id__in=bookmarked_ids)
 
-        # Filter by downloaded books if requested
-        is_downloaded = self.request.query_params.get('is_downloaded', '').lower()
-        if is_downloaded == 'true':
-            # Get all downloaded book IDs for the current user
-            downloaded_ids = BookDownload.objects.filter(
-                user=self.request.user,
-                status=True
-            ).values_list('book_id', flat=True)
-            
-            # Filter books by these IDs
-            queryset = queryset.filter(id__in=downloaded_ids)
-
         return queryset.order_by('-pin', '-created_at')
 
 
@@ -191,6 +179,59 @@ class MiddleBookCollectionListView(ListAPIView):
         ).order_by('order')
 
 
+class DownloadedBooksListView(ListAPIView):
+    """
+    API view to list books that have been downloaded by the current user
+    """
+    serializer_class = BookSerializer
+    permission_classes = (IsAuthenticated,)
+    filter_backends = [SearchFilter]
+    search_fields = ['title', 'summary', 'publisher', 'isbn']
+
+    @swagger_auto_schema(
+        operation_id="list_downloaded_books",
+        operation_description="""
+        Retrieve a list of books that have been downloaded by the current user.
+        
+        This endpoint returns a paginated list of books that the authenticated user has downloaded.
+        The results are not cached to ensure real-time accuracy of the download list.
+        
+        You can search for downloaded books by title, summary, publisher, or ISBN using the 'search' query parameter.
+        """,
+        operation_summary="List Downloaded Books",
+        tags=["Library"],
+        manual_parameters=[
+            openapi.Parameter(
+                'search',
+                openapi.IN_QUERY,
+                description="Search downloaded books by title, summary, publisher, or ISBN",
+                type=openapi.TYPE_STRING,
+                required=False
+            )
+        ],
+        responses={
+            200: "List of downloaded books with pagination",
+            401: "Authentication credentials were not provided or are invalid",
+            500: "Internal server error occurred"
+        }
+    )
+    def get(self, request, *args, **kwargs):
+        return super().get(request, *args, **kwargs)
+
+    def get_queryset(self):
+        # Get all downloaded book IDs for the current user
+        downloaded_ids = BookDownload.objects.filter(
+            user=self.request.user,
+            status=True
+        ).values_list('book_id', flat=True)
+        
+        # Return books that match these IDs
+        return Book.objects.filter(
+            id__in=downloaded_ids,
+            status=True
+        ).order_by('-created_at')
+
+
 class BookDownloadCreateAPIView(CreateAPIView):
     """
     API view to create a book download record and increment the book's download count