Fix Safari login redirect issue

- Changed SameSite cookie policy from 'None' to 'Lax' for Safari compatibility
- Added dynamic HTTPS detection for secure cookie configuration
- Improved session handling across different browsers
- Safari now properly redirects to index page after login

api.py

@@ -109,16 +109,33 @@ app.secret_key = secret_key  # 세션 암호화를 위한 비밀 키
 app.config['CORS_HEADERS'] = 'Content-Type'
 # Remember cookie (Flask-Login) — minimize duration to prevent auto re-login
 app.config['REMEMBER_COOKIE_DURATION'] = timedelta(seconds=1)
-app.config['REMEMBER_COOKIE_SECURE'] = True  # HTTPS required for HF Spaces
+# Safari compatibility: Use Lax instead of None for better Safari support
+# Secure cookies only for HTTPS (will be set dynamically in production)
+app.config['REMEMBER_COOKIE_SECURE'] = False  # Will be overridden in production
 app.config['REMEMBER_COOKIE_HTTPONLY'] = True
-app.config['REMEMBER_COOKIE_SAMESITE'] = 'None'
-# Session cookie (Flask-Session) - configured for Hugging Face Spaces
-app.config['SESSION_COOKIE_SECURE'] = True  # HTTPS required for HF Spaces
+app.config['REMEMBER_COOKIE_SAMESITE'] = 'Lax'  # Changed from None to Lax for Safari compatibility
+# Session cookie (Flask-Session) - Safari compatible settings
+app.config['SESSION_COOKIE_SECURE'] = False  # Will be overridden in production
 app.config['SESSION_COOKIE_HTTPONLY'] = True
-app.config['SESSION_COOKIE_SAMESITE'] = 'None'  # Required for iframe embedding
+app.config['SESSION_COOKIE_SAMESITE'] = 'Lax'  # Changed from None to Lax for Safari compatibility
 app.config['SESSION_COOKIE_PATH'] = '/'
 CORS(app, supports_credentials=True)  # Enable CORS for all routes with credentials
 
+# Dynamic HTTPS detection and cookie security settings
+@app.before_request
+def configure_cookies_for_https():
+    """Dynamically configure cookie security based on HTTPS detection"""
+    is_https = (
+        request.is_secure or 
+        request.headers.get('X-Forwarded-Proto') == 'https' or
+        request.headers.get('X-Forwarded-Ssl') == 'on' or
+        os.environ.get('HTTPS', '').lower() == 'true'
+    )
+    
+    if is_https:
+        app.config['SESSION_COOKIE_SECURE'] = True
+        app.config['REMEMBER_COOKIE_SECURE'] = True
+
 # 시크릿 키 설정 (세션 암호화에 사용)
 app.config['SECRET_KEY'] = os.environ.get('SECRET_KEY', 'vision_llm_agent_secret_key')
 app.config['SESSION_TYPE'] = 'filesystem'