First try version of the kitchen PIR

src/main.cpp

@@ -61,13 +61,16 @@ void reconnect() {
   }
 }
 
-void send_mqtt(String value) {
+void send_mqtt(String status, long time_min=0) {
   const size_t CAPACITY = JSON_OBJECT_SIZE(1);
   StaticJsonDocument<CAPACITY> doc;
 
   // create an object
   JsonObject object = doc.to<JsonObject>();
-  object["status"] = value.c_str();
+  object["status"] = status.c_str();
+  if (time_min > 0) {
+    object["minutes"] = time_min;
+  }
 
   // serialize the object and send the result to Serial
   static char sensorStatus[150];
@@ -88,17 +91,31 @@ void setup() {
 
 }
 
+long previousMotionMillis=millis();
+short previousState=digitalRead(PIR_PIN);
+long previousNoMoNotifyMins=0;
 void loop() {
   if (!mqttClient.connected()) {
     reconnect();
   }
   mqttClient.loop();
 
-  int pir = digitalRead(PIR_PIN);
-  if (pir == HIGH) {
+  short currentState = digitalRead(PIR_PIN);
+  if (currentState != previousState) {
+    if (currentState == HIGH) {
       send_mqtt("motion");
       digitalWrite(LED_BUILTIN,HIGH);
       delay(1000);
       digitalWrite(LED_BUILTIN,LOW);
+      previousMotionMillis=millis();
     } 
+    previousState = currentState;
+  }
+
+  long minsSinceLastMotion=(millis()-previousMotionMillis)/(1000*60);
+  if (previousNoMoNotifyMins != minsSinceLastMotion) {
+    send_mqtt("no_motion",minsSinceLastMotion);
+    previousNoMoNotifyMins = minsSinceLastMotion;
+  }
+  
 }