globals.h

include/change_detector.h

@@ -0,0 +1,35 @@
+#pragma once
+#include <Arduino.h>
+
+template <typename T, size_t MaxObservers>
+class Detector {
+public:
+    explicit Detector(T initial) : value(initial) {
+        for (size_t i = 0; i < MaxObservers; ++i) seen[i] = false;
+    }
+
+    void set(const T& v) {
+        if (v == value) return;
+
+        value = v;
+        for (size_t i = 0; i < MaxObservers; ++i) seen[i] = false;
+    }
+
+    bool changed(size_t id) {
+        if (id >= MaxObservers) return false;
+
+        if (!seen[id]) {
+            seen[id] = true;
+            return true;
+        }
+        return false;
+    }
+
+    const T& get() const {
+        return value;
+    }
+
+private:
+    T value;
+    bool seen[MaxObservers];
+};