Enhance DaliCloudBridge: add JSON escaping function and buildRegisterPayload for improved payload formatting

Signed-off-by: Tony <tonylu@tony-cloud.com>

src/gateway_cloud.cpp

@@ -12,6 +12,34 @@ extern "C" {
 namespace {
 constexpr const char* kTag = "dali_cloud_bridge";
 
+std::string jsonEscape(const std::string& value) {
+  std::string out;
+  out.reserve(value.size() + 8);
+  for (char ch : value) {
+    switch (ch) {
+      case '\\':
+        out += "\\\\";
+        break;
+      case '"':
+        out += "\\\"";
+        break;
+      case '\n':
+        out += "\\n";
+        break;
+      case '\r':
+        out += "\\r";
+        break;
+      case '\t':
+        out += "\\t";
+        break;
+      default:
+        out.push_back(ch);
+        break;
+    }
+  }
+  return out;
+}
+
 std::string toString(const cJSON* item) {
   if (item == nullptr) {
     return "";
@@ -180,6 +208,22 @@ bool DaliCloudBridge::publishRegister(const std::string& payloadJson) {
   return publishJSON(topicRegister(), payloadJson);
 }
 
+#ifdef ESP_PLATFORM
+std::string buildRegisterPayload(const GatewayCloudConfig& config) {
+  const std::string deviceID = jsonEscape(config.deviceID);
+  std::ostringstream oss;
+  oss << "{\"type\":\"register\","
+      << "\"status\":\"online\","
+      << "\"device_id\":\"" << deviceID << "\","
+      << "\"base_mac\":\"" << deviceID << "\","
+      << "\"identifier\":\"" << deviceID << "\","
+      << "\"identifier_type\":\"mac\","
+      << "\"gateway_type\":\"dali_cpp\","
+      << "\"topic_prefix\":\"" << jsonEscape(config.topicPrefix) << "\"}";
+  return oss.str();
+}
+#endif
+
 bool DaliCloudBridge::publishJSON(const std::string& topic, const std::string& payloadJson) {
 #ifdef ESP_PLATFORM
   if (client_ == nullptr || !connected_.load()) {
@@ -318,7 +362,7 @@ void DaliCloudBridge::onMqttEvent(esp_mqtt_event_handle_t event) {
       ESP_LOGI(kTag, "MQTT connected");
       esp_mqtt_client_subscribe(client_, topicDown().c_str(), config_.qos);
       publishStatus("online");
-      publishRegister("{\"type\":\"register\",\"status\":\"online\"}");
+      publishRegister(buildRegisterPayload(config_));
       break;
     }
     case MQTT_EVENT_DISCONNECTED: