index.html is now served from SPIFFS. You can add rfid tag -> folder mappings via the webinterface. And I've added the missing controller json data messages.

src/playlist_manager.cpp

@@ -110,3 +110,19 @@ String PlaylistManager::json() {
 	}
 	return json.as<String>();
 }
+
+bool PlaylistManager::add_mapping(String id, String folder) {
+	DEBUG("Adding Mapping: '%s'=>'%s'\n", id.c_str(), folder.c_str());
+	if (!SD.exists(folder)) return false;
+	File ids = SD.open(folder + "/ids.txt", "a");
+	String data = "\n";
+	data += id;
+	data += '\n';
+	char* buffer = new char[data.length()];
+	data.toCharArray(buffer, data.length());
+	ids.write((uint8_t *)buffer, data.length());
+	delete buffer;
+	ids.close();
+	_map[id] = folder;
+	return true;
+}