refactor: migrate TikTok polling from external cron to internal Next.js instrumentation interval

lib/autofeed.ts

@@ -0,0 +1,59 @@
+import { getRedisClient } from "@/lib/redis";
+import { sendDiscordNotification } from "@/lib/discord";
+import { getLatestTiktokVideo, getTiktokProfile } from "@/lib/followers/tiktok";
+
+async function checkTiktokFeed() {
+  try {
+    const latestVideo = await getLatestTiktokVideo();
+    if (!latestVideo) return;
+
+    const redis = await getRedisClient();
+    const redisKey = "erika:tiktok_last_video_id";
+    const lastVideoId = await redis.get(redisKey);
+
+    if (lastVideoId === latestVideo.id) {
+      return; // Already notified
+    }
+
+    let officialAuthorName = "TikTok";
+    let officialAvatarUrl: string | undefined = undefined;
+    try {
+      const profile = await getTiktokProfile();
+      if (profile.displayName) officialAuthorName = profile.displayName;
+      if (profile.avatarUrl) officialAvatarUrl = profile.avatarUrl;
+    } catch (e) {
+      console.error("[TikTok Feed] Failed to fetch profile:", e);
+    }
+
+    const message = `ลงคลิปใหม่แล้วววสสสสส ${latestVideo.shareUrl}`;
+    const embed = {
+      title: latestVideo.title || "คลิปใหม่จาก TikTok",
+      url: latestVideo.shareUrl || undefined,
+      color: 0xff0050,
+      author: {
+        name: officialAuthorName,
+        url: latestVideo.shareUrl || "https://www.tiktok.com/",
+        icon_url: officialAvatarUrl || undefined
+      },
+      image: latestVideo.coverImageUrl ? { url: latestVideo.coverImageUrl } : undefined
+    };
+
+    await sendDiscordNotification(message, embed);
+    await redis.set(redisKey, latestVideo.id);
+  } catch (error) {
+    console.error("[TikTok Feed] Error processing:", error);
+  }
+}
+
+export function startTiktokFeedInterval() {
+  if (!(global as any).tiktokFeedIntervalStarted) {
+    (global as any).tiktokFeedIntervalStarted = true;
+    console.log("[TikTok Feed] Starting 5-minute interval check in background...");
+    
+    // Run immediately on start
+    checkTiktokFeed();
+    
+    // Then every 5 minutes
+    setInterval(checkTiktokFeed, 5 * 60 * 1000);
+  }
+}

lib/followers/tiktok.ts

@@ -1,12 +1,3 @@
-/**
- * Fetches TikTok follower count using the official TikTok API v2.
- *
- * Required env vars:
- * - TIKTOK_CLIENT_KEY
- * - TIKTOK_CLIENT_SECRET
- * - TIKTOK_REFRESH_TOKEN (obtained via one-time OAuth flow at /api/auth/tiktok)
- */
-
 let cachedAccessToken: string | null = null;
 let tokenExpiresAt = 0;
 
@@ -143,4 +134,4 @@ export async function getLatestTiktokVideo(): Promise<TiktokVideo | null> {
     console.error("[TikTok API] Error fetching latest video via TikWM:", e);
     return null;
   }
-}
+}