From d5af5e9b7d8ff091f5a35db50baac010b1655b40 Mon Sep 17 00:00:00 2001
From: "Gan, Jimmy" <jimmy.gan@adidas.com>
Date: Wed, 24 Jun 2026 02:38:04 +0800
Subject: [PATCH] =?UTF-8?q?feat:=20rotate=2050=20channels=20daily=20?=
 =?UTF-8?q?=E2=80=94=20covers=20all=20229=20over=205=20days?=
MIME-Version: 1.0
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---
 backend/fetcher.py | 33 +++++++++++++++++++++++++++++++--
 1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/backend/fetcher.py b/backend/fetcher.py
index d73f0e8..d3518bf 100644
--- a/backend/fetcher.py
+++ b/backend/fetcher.py
@@ -1,4 +1,5 @@
 import asyncio
+import os
 import html
 import logging
 import aiosqlite
@@ -9,6 +10,33 @@ from db import DB_PATH
 
 log = logging.getLogger(__name__)
 
+ROTATION_FILE = os.environ.get("ROTATION_FILE", os.path.join(os.path.dirname(os.path.dirname(os.path.abspath(__file__))), "config", "rotation.txt"))
+
+def get_rotation_batch(channel_ids, batch_size=50):
+    """Read last position, return next batch of channels, save new position."""
+    offset = 0
+    try:
+        if os.path.exists(ROTATION_FILE):
+            with open(ROTATION_FILE) as f:
+                offset = int(f.read().strip())
+    except: pass
+    
+    total = len(channel_ids)
+    if offset >= total:
+        offset = 0
+    
+    end = min(offset + batch_size, total)
+    batch = channel_ids[offset:end]
+    
+    # Save next offset
+    new_offset = end if end < total else 0
+    os.makedirs(os.path.dirname(ROTATION_FILE), exist_ok=True)
+    with open(ROTATION_FILE, 'w') as f:
+        f.write(str(new_offset))
+    
+    log.info(f"Rotation: channels {offset+1}-{end} of {total} (next starts at {new_offset})")
+    return batch
+
 async def fetch_subscriptions():
     """Fetch latest videos from subscribed channels using YouTube Data API v3."""
     try:
@@ -48,10 +76,11 @@ async def fetch_subscriptions():
         log.warning("No subscribed channels found. Make sure the authenticated account has subscriptions.")
         return 0
 
-    # Step 2: For each channel, get latest videos
+    # Step 2: For each channel in today's rotation batch, get latest videos
+    batch = get_rotation_batch(channel_ids)
     new_count = 0
     async with aiosqlite.connect(DB_PATH) as db:
-        for cid in channel_ids[:50]:
+        for cid in batch:
             try:
                 req = youtube.search().list(
                     part="snippet",