add media upload functionality and management interface

app.py

@@ -114,8 +114,24 @@ def logout():
 @admin_required
 def upload_content():
     if request.method == 'POST':
-        # Handle file upload logic here
-        pass
+        target_type = request.form['target_type']
+        target_id = int(request.form['target_id'])
+        files = request.files.getlist('files')
+        duration = int(request.form['duration'])
+        return_url = request.form['return_url']
+        
+        for file in files:
+            filename = secure_filename(file.filename)
+            file_path = os.path.join(app.config['UPLOAD_FOLDER'], filename)
+            file.save(file_path)
+            if target_type == 'player':
+                new_content = Content(file_name=filename, duration=duration, player_id=target_id)
+            elif target_type == 'group':
+                new_content = Content(file_name=filename, duration=duration, group_id=target_id)
+            db.session.add(new_content)
+        
+        db.session.commit()
+        return redirect(return_url)
 
     target_type = request.args.get('target_type')
     target_id = request.args.get('target_id')