dashboard: queue latest relay target states

firmware/esp32-s3-dashboard/esp32-s3-dashboard.ino

@@ -62,11 +62,9 @@ static bool metadata_refresh_requested = true;
 static bool was_wifi_connected = false;
 static bool overview_screen_created = false;
 
-static bool relay_command_pending = false;
-static String pending_relay_id;
-static bool pending_relay_state = false;
-static int pending_relay_index = -1;
-static bool pending_relay_previous_state = false;
+static bool relay_command_pending[6] = {false};
+static bool pending_relay_state[6] = {false};
+static bool pending_relay_previous_state[6] = {false};
 
 static String last_battery_current_text;
 static String last_battery_estimate_text;
@@ -529,7 +527,7 @@ static void relay_button_event_cb(lv_event_t *event)
     intptr_t index_value = reinterpret_cast<intptr_t>(lv_event_get_user_data(event));
     int index = static_cast<int>(index_value);
 
-    if (index < 0 || index >= relay_count || relay_command_pending) {
+    if (index < 0 || index >= relay_count) {
         return;
     }
 
@@ -539,11 +537,13 @@ static void relay_button_event_cb(lv_event_t *event)
     relay_states[index] = next_state;
     update_relay_buttons();
 
-    pending_relay_id = relay_ids[index];
-    pending_relay_state = next_state;
-    pending_relay_index = index;
-    pending_relay_previous_state = previous_state;
-    relay_command_pending = true;
+    if (!relay_command_pending[index]) {
+        pending_relay_previous_state[index] = previous_state;
+    }
+
+    // Latest-state queue: rapid taps overwrite this relay's desired target.
+    pending_relay_state[index] = next_state;
+    relay_command_pending[index] = true;
 
     String text = "Queued ";
     text += relay_names[index];
@@ -555,26 +555,37 @@ static void relay_button_event_cb(lv_event_t *event)
 
 static void process_pending_relay_command()
 {
-    if (!relay_command_pending || api_request_in_progress) {
+    if (api_request_in_progress) {
         return;
     }
 
-    String relay_id = pending_relay_id;
-    bool next_state = pending_relay_state;
-    int index = pending_relay_index;
-    bool previous_state = pending_relay_previous_state;
+    int index = -1;
+    for (int i = 0; i < relay_count; i++) {
+        if (relay_command_pending[i]) {
+            index = i;
+            break;
+        }
+    }
+
+    if (index < 0) {
+        return;
+    }
+
+    String relay_id = relay_ids[index];
+    bool next_state = pending_relay_state[index];
+    bool previous_state = pending_relay_previous_state[index];
+
+    // Clear before posting. If the user taps again after this command returns,
+    // the new desired state will be queued as a fresh command.
+    relay_command_pending[index] = false;
 
     bool ok = post_relay_state(relay_id, next_state);
 
-    relay_command_pending = false;
-    pending_relay_id = "";
-    pending_relay_index = -1;
-
     if (ok) {
         set_label_text_if_changed(system_status_label, last_system_status_text, "Relay command sent");
-        request_fast_status_refresh();
     } else {
-        if (index >= 0 && index < relay_count) {
+        // Only revert if no newer desired state was queued for this relay.
+        if (!relay_command_pending[index] && index >= 0 && index < relay_count) {
             relay_states[index] = previous_state;
             update_relay_buttons();
         }