fix(comments): validate pagination params (#131)

Co-authored-by: rissrice2105-agent <289161642+rissrice2105-agent@users.noreply.github.com>

Author: rissrice2105-agent

src/app/api/torrents/[id]/comments/route.test.ts

@@ -134,6 +134,25 @@ describe('Torrent Comments API', () => {
       expect(mockService.getCommentsWithUserVotes).toHaveBeenCalledWith(TEST_TORRENT_ID, null, 10, 20);
     });
 
+    it('should fall back to safe pagination for malformed params', async () => {
+      const mockService = {
+        getCommentsWithUserVotes: vi.fn().mockResolvedValue([]),
+        getCommentCount: vi.fn().mockResolvedValue(0),
+      };
+
+      (getCommentsService as ReturnType<typeof vi.fn>).mockReturnValue(mockService);
+      (getActiveProfileId as ReturnType<typeof vi.fn>).mockResolvedValue(null);
+
+      const request = new NextRequest(
+        `http://localhost/api/torrents/${TEST_TORRENT_ID}/comments?limit=10items&offset=-20`
+      );
+      const response = await GET(request, { params: Promise.resolve({ id: TEST_TORRENT_ID }) });
+
+      expect(response.status).toBe(200);
+      expect(mockService.getCommentsWithUserVotes).toHaveBeenCalledWith(TEST_TORRENT_ID, null, 50, 0);
+      await expect(response.json()).resolves.toMatchObject({ limit: 50, offset: 0 });
+    });
+
     it('should return 400 for missing torrent ID', async () => {
       const request = new NextRequest('http://localhost/api/torrents//comments');
       const response = await GET(request, { params: Promise.resolve({ id: '' }) });

src/app/api/torrents/[id]/comments/route.ts

@@ -12,6 +12,7 @@ import { NextRequest, NextResponse } from 'next/server';
 import { getCommentsService } from '@/lib/comments';
 import { getAuthenticatedUser } from '@/lib/auth';
 import { getActiveProfileId } from '@/lib/profiles/profile-utils';
+import { parseIntegerParam } from '@/lib/api/pagination';
 
 interface RouteParams {
   params: Promise<{ id: string }>;
@@ -50,8 +51,8 @@ export async function GET(
 
     // Parse pagination params
     const searchParams = request.nextUrl.searchParams;
-    const limit = parseInt(searchParams.get('limit') ?? '50', 10);
-    const offset = parseInt(searchParams.get('offset') ?? '0', 10);
+    const limit = parseIntegerParam(searchParams.get('limit'), { min: 1, max: 100 }) ?? 50;
+    const offset = parseIntegerParam(searchParams.get('offset'), { min: 0 }) ?? 0;
 
     // DHT torrents (non-UUID IDs) don't support comments
     // Return empty results instead of failing