Encoder: Return encoder event

firmware/src/encoder.cpp

@@ -14,6 +14,16 @@ When rotated clockwise, CLK changes before DT; when rotated counter-clockwise, D
 
 #define SW_DEBOUNCE_MS 10
 
+typedef uint8_t SwitchEvent;
+#define SWITCH_NONE 0
+#define SWITCH_PRESSED 1
+#define SWITCH_RELEASED 2
+
+typedef int8_t EncoderEvent;
+#define ENCODER_NONE 0
+#define ENCODER_CLOCKWISE 1
+#define ENCODER_COUNTER_CLOCKWISE -1
+
 bool previousClk = false;
 bool previousDt = false;
 
@@ -27,45 +37,51 @@ void setupEncoder() {
   previousDt = digitalRead(DT_PIN);
 }
 
-void handleSwitch();
+SwitchEvent handleSwitch();
+EncoderEvent handleEncoder();
 
 void demoEncoder() {
-  handleSwitch();
-  handleEncoder();
+  if (auto event = handleSwitch()) {
+    Serial.println(event == SWITCH_PRESSED ? "Pressed" : "Released");
+  }
+
+  if (auto event = handleEncoder()) {
+    Serial.println(event == ENCODER_CLOCKWISE ? "Clockwise" : "Counter-clockwise");
+  }
 }
 
 bool previousPressed = false;
 unsigned long lastChangeAt = 0;
 
-void handleSwitch() {
+SwitchEvent handleSwitch() {
   bool isPressed = !digitalRead(SW_PIN);
 
   // only handle change
   if (isPressed == previousPressed) {
-    return;
+    return SWITCH_NONE;
   }
 
   // debounce
   unsigned long now = millis();
   if (now - lastChangeAt < SW_DEBOUNCE_MS) {
-    return;
+    return SWITCH_NONE;
   }
 
   // save state
   previousPressed = isPressed;
   lastChangeAt = now;
 
-  // handle change
-  Serial.println(isPressed ? "Pressed" : "Released");
+  // return event
+  return isPressed ? SWITCH_PRESSED : SWITCH_RELEASED;
 }
 
-void handleEncoder() {
+EncoderEvent handleEncoder() {
   bool clk = digitalRead(CLK_PIN);
   bool dt = digitalRead(DT_PIN);
 
   // only handle change
   if (clk == previousClk && dt == previousDt) {
-    return;
+    return ENCODER_NONE;
   }
 
   // TODO: Do we need to debounce encoder?
@@ -76,15 +92,15 @@ void handleEncoder() {
   // counter-clockwise pattern:
   // clk: 1100 1100
   // dt:  1001 1001
+  EncoderEvent event = ENCODER_NONE;
   if (clk == dt) {
-    if (clk == previousClk) {
-      Serial.println("Clockwise");
-    } else {
-      Serial.println("Counter-clockwise");
-    }
+    event = clk == previousClk ? ENCODER_CLOCKWISE : ENCODER_COUNTER_CLOCKWISE;
   }
 
   // save state
   previousClk = clk;
   previousDt = dt;
+
+  // return event
+  return event;
 }