feat(traffic): add per-IP daily traffic tracking with 20GB limit for uploads and downloads

database.py

@@ -1,7 +1,7 @@
 import sqlite3
 import os
 from datetime import datetime, timedelta
-from config import DATABASE
+from config import DATABASE, DAILY_TRAFFIC_LIMIT
 
 def get_db():
     conn = sqlite3.connect(DATABASE)
@@ -22,6 +22,16 @@ def init_db():
             expires_at TIMESTAMP NOT NULL
         )
     ''')
+    conn.execute('''
+        CREATE TABLE IF NOT EXISTS ip_traffic (
+            id INTEGER PRIMARY KEY AUTOINCREMENT,
+            ip TEXT NOT NULL,
+            date TEXT NOT NULL,
+            upload_bytes INTEGER NOT NULL DEFAULT 0,
+            download_bytes INTEGER NOT NULL DEFAULT 0,
+            UNIQUE(ip, date)
+        )
+    ''')
     conn.commit()
     conn.close()
 
@@ -59,3 +69,53 @@ def cleanup_expired():
     conn.commit()
     conn.close()
     return len(expired)
+
+def get_client_ip(request):
+    if 'X-Forwarded-For' in request.headers:
+        return request.headers['X-Forwarded-For'].split(',')[0].strip()
+    if 'X-Real-IP' in request.headers:
+        return request.headers['X-Real-IP'].strip()
+    return request.remote_addr
+
+def add_upload_traffic(ip, bytes_count):
+    today = datetime.utcnow().strftime('%Y-%m-%d')
+    conn = get_db()
+    conn.execute('''
+        INSERT INTO ip_traffic (ip, date, upload_bytes, download_bytes)
+        VALUES (?, ?, ?, 0)
+        ON CONFLICT(ip, date) DO UPDATE SET upload_bytes = upload_bytes + ?
+    ''', (ip, today, bytes_count, bytes_count))
+    conn.commit()
+    conn.close()
+
+def add_download_traffic(ip, bytes_count):
+    today = datetime.utcnow().strftime('%Y-%m-%d')
+    conn = get_db()
+    conn.execute('''
+        INSERT INTO ip_traffic (ip, date, upload_bytes, download_bytes)
+        VALUES (?, ?, 0, ?)
+        ON CONFLICT(ip, date) DO UPDATE SET download_bytes = download_bytes + ?
+    ''', (ip, today, bytes_count, bytes_count))
+    conn.commit()
+    conn.close()
+
+def get_daily_traffic(ip):
+    today = datetime.utcnow().strftime('%Y-%m-%d')
+    conn = get_db()
+    row = conn.execute(
+        'SELECT upload_bytes, download_bytes FROM ip_traffic WHERE ip = ? AND date = ?',
+        (ip, today)
+    ).fetchone()
+    conn.close()
+    if row:
+        return row['upload_bytes'], row['download_bytes']
+    return 0, 0
+
+def is_traffic_exceeded(ip, additional_bytes, direction='upload'):
+    upload, download = get_daily_traffic(ip)
+    total = upload + download
+    if direction == 'upload':
+        total += additional_bytes
+    else:
+        total += additional_bytes
+    return total > DAILY_TRAFFIC_LIMIT