fix(iptv): validate channel pagination (#132)

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

Author: rissrice2105-agent

src/app/api/iptv/channels/route.test.ts

@@ -14,7 +14,9 @@ const mockCacheSet = vi.fn();
 // Mock undici fetch
 const mockFetch = vi.fn();
 vi.mock('undici', () => ({
-  Agent: vi.fn().mockImplementation(() => ({})),
+  Agent: vi.fn(function MockAgent() {
+    return {};
+  }),
   fetch: mockFetch,
 }));
 
@@ -233,6 +235,38 @@ describe('IPTV Channels API', () => {
       expect(data.limit).toBe(10);
     });
 
+    it.each([
+      ['negative', '-5', '-20'],
+      ['partially numeric', '10items', '20items'],
+    ])('uses pagination defaults for %s values', async (_label, limit, offset) => {
+      const allChannels = Array.from({ length: 100 }, (_, i) => ({
+        id: String(i),
+        name: `Channel ${i}`,
+        url: `https://example.com/ch${i}.m3u8`,
+        group: 'General',
+      }));
+      mockCacheGet.mockResolvedValue({
+        channels: allChannels,
+        groups: ['General'],
+        fetchedAt: Date.now(),
+        m3uUrl: 'http://example.com/playlist.m3u',
+      });
+      vi.mocked(searchChannels).mockReturnValue(allChannels);
+
+      const request = new NextRequest(
+        `http://localhost/api/iptv/channels?m3uUrl=http://example.com/playlist.m3u&limit=${limit}&offset=${offset}`
+      );
+
+      const response = await GET(request);
+      const data = await response.json();
+
+      expect(response.status).toBe(200);
+      expect(data.channels).toHaveLength(50);
+      expect(data.limit).toBe(50);
+      expect(data.offset).toBe(0);
+      expect(data.channels[0].id).toBe('0');
+    });
+
     it('returns 502 when upstream fetch fails', async () => {
       mockCacheGet.mockResolvedValue(null);
 

src/app/api/iptv/channels/route.ts

@@ -24,6 +24,7 @@ import {
 } from '@/lib/iptv';
 import { getIptvCacheReader } from '@/lib/iptv/cache-reader';
 import { createServerClient } from '@/lib/supabase';
+import { parseIntegerParam } from '@/lib/api/pagination';
 
 /**
  * Undici agent that ignores SSL certificate errors.
@@ -90,11 +91,9 @@ export async function GET(request: NextRequest): Promise<Response> {
   const m3uUrl = searchParams.get('m3uUrl');
   const query = searchParams.get('q') ?? '';
   const group = searchParams.get('group') ?? undefined;
-  const limit = Math.min(
-    parseInt(searchParams.get('limit') ?? String(DEFAULT_LIMIT), 10) || DEFAULT_LIMIT,
-    MAX_LIMIT
-  );
-  const offset = parseInt(searchParams.get('offset') ?? '0', 10) || 0;
+  const parsedLimit = parseIntegerParam(searchParams.get('limit'), { min: 1 });
+  const limit = Math.min(parsedLimit ?? DEFAULT_LIMIT, MAX_LIMIT);
+  const offset = parseIntegerParam(searchParams.get('offset'), { min: 0 }) ?? 0;
 
   // Validate that at least one identifier is provided
   if (!playlistId && !m3uUrl) {

vitest.config.ts

@@ -49,7 +49,6 @@ export default defineConfig({
       // Tests failing after vitest 3→4 migration (pre-existing failures, tracked separately)
       'src/app/api/browse/route.test.ts',
       'src/app/api/ice/turn/route.test.ts',
-      'src/app/api/iptv/channels/route.test.ts',
       'src/app/api/iptv/playlists/[id]/route.test.ts',
       'src/app/api/iptv/playlists/route.test.ts',
       'src/app/api/magnets/route.test.ts',