Add queuing of messages

esp32_MachineNotify.ino

@@ -12,6 +12,11 @@ const char* WIFI_PASSWORD = "YOUR_WIFI_PASSWORD";
 // ntfy.sh topic
 const char* NTFY_TOPIC = "YOUR_NTFY_TOPIC";
 
+// Notification queue
+String queuedNotification = "";
+String queuedTitle = "";
+String queuedPriority = "";
+
 // Pin definitions
 const int VIBRATION_PIN = 4;
 
@@ -94,10 +99,22 @@ void setup() {
   delay(1000);
 }
 
-void sendNotification(String message);
+bool sendNotification(String message, String title, String priority);
 void updateDisplay();
 
 void loop() {
+  // Try to send any queued notification
+  if (queuedNotification != "") {
+    if (sendNotification(queuedNotification, queuedTitle, queuedPriority)) {
+      Serial.println("Successfully sent queued notification.");
+      queuedNotification = ""; // Clear queue
+      queuedTitle = "";
+      queuedPriority = "";
+    } else {
+      // Failed, will retry on next loop
+    }
+  }
+
   unsigned long currentTime = millis();
 
   // Sensor readings
@@ -156,10 +173,23 @@ void loop() {
   isDeviceActive = isVibrationActive || isLightActive;
 
   if (isDeviceActive != previousDeviceState) {
+    String message;
+    String title;
+    String priority;
     if (isDeviceActive) {
-      sendNotification("Washing machine cycle started.");
+      message = "Washing machine cycle started.";
+      title = "Machine START";
+      priority = "default";
     } else {
-      sendNotification("Washing machine cycle finished.");
+      message = "Washing machine cycle finished.";
+      title = "Machine END";
+      priority = "high";
+    }
+
+    if (!sendNotification(message, title, priority)) {
+      queuedNotification = message; // Failed to send, queue it (overwrites any older one)
+      queuedTitle = title;
+      queuedPriority = priority;
     }
   }
 
@@ -173,26 +203,30 @@ void loop() {
   updateDisplay();
 }
 
-void sendNotification(String message) {
+bool sendNotification(String message, String title, String priority) {
   if (WiFi.status() == WL_CONNECTED) {
     HTTPClient http;
     String url = "http://ntfy.sh/" + String(NTFY_TOPIC);
     http.begin(url);
     http.addHeader("Content-Type", "text/plain");
+    http.addHeader("Title", title);
+    http.addHeader("Priority", priority);
 
     int httpResponseCode = http.POST(message);
+    http.end();
 
     if (httpResponseCode > 0) {
       Serial.print("HTTP Response code: ");
       Serial.println(httpResponseCode);
+      return true;
     } else {
       Serial.print("Error on sending POST: ");
       Serial.println(httpResponseCode);
+      return false;
     }
-
-    http.end();
   } else {
     Serial.println("WiFi Disconnected. Cannot send notification.");
+    return false;
   }
 }