Backend for RELAY_MODE_FOLLOW

code/espurna/button.ino

@@ -30,6 +30,18 @@ void buttonMQTT(unsigned char id, uint8_t event) {
 }
 #endif
 
+int buttonFromRelay(unsigned int relayID) {
+    for (unsigned int i=0; i < _buttons.size(); i++) {
+        if (_buttons[i].relayID == relayID) return i;
+    }
+    return -1;
+}
+
+bool buttonState(unsigned char id) {
+    if (id >= _buttons.size()) return false;
+    return _buttons[id].button->pressed();
+}
+
 unsigned char buttonAction(unsigned char id, unsigned char event) {
     if (id >= _buttons.size()) return BUTTON_MODE_NONE;
     unsigned long actions = _buttons[id].actions;

code/espurna/config/general.h

@@ -62,6 +62,7 @@
 #define RELAY_MODE_ON           1
 #define RELAY_MODE_SAME         2
 #define RELAY_MODE_TOOGLE       3
+#define RELAY_MODE_FOLLOW       4
 
 #define RELAY_SYNC_ANY          0
 #define RELAY_SYNC_NONE_OR_ONE  1
@@ -90,6 +91,7 @@
 
 // Relay requests flood protection window - in seconds
 #define RELAY_FLOOD_WINDOW      3
+
 // Allowed actual relay changes inside requests flood protection window
 #define RELAY_FLOOD_CHANGES     5
 

code/espurna/relay.ino

@@ -477,6 +477,11 @@ void relaySetup() {
         pinMode(_relays[i].pin, OUTPUT);
         if (relayMode == RELAY_MODE_OFF) relayStatus(i, false);
         if (relayMode == RELAY_MODE_ON) relayStatus(i, true);
+        if (relayMode == RELAY_MODE_FOLLOW) {
+            // retrieve the status of the linked button
+            int buttonID = buttonFromRelay(i);
+            relayStatus(i, (buttonID >=0) ? buttonState(buttonID) : false);
+        }
     }
     if (relayMode == RELAY_MODE_SAME) relayRetrieve(false);
     if (relayMode == RELAY_MODE_TOOGLE) relayRetrieve(true);