Dynamically switch between animation framework and UDP control

include/UDPProto.h

@@ -16,10 +16,13 @@ public:
 
     UDPProto(Fader *fader);
 
+
     bool start(uint16_t port);
+
+    bool check(void);
     bool loop(void);
 
 private:
     WiFiUDP m_udpServer;
     Fader *m_fader;
-};
+};

src/UDPProto.cpp

@@ -23,6 +23,22 @@ bool UDPProto::start(uint16_t port)
 	return true;
 }
 
+bool UDPProto::check(void)
+{
+	int packetSize = m_udpServer.parsePacket();
+	if(packetSize) {
+		byte buf[1024];
+		int len;
+		while((len = m_udpServer.read(buf, 1024)) == 1024) {
+			// do nothing
+		}
+		m_udpServer.endPacket();
+		return true;
+	} else {
+		return false;
+	}
+}
+
 bool UDPProto::loop(void)
 {
 	byte cmd[WS2801_CMD_LEN];

src/main.cpp

@@ -87,6 +87,82 @@ bool initLEDs()
   return true;
 }
 
+enum LEDState {
+  UDP,
+  ANIMATION,
+  TRANSITION
+};
+
+static void ledFSM(void)
+{
+  static bool stateEntered = true;
+  static LEDState ledState = ANIMATION;
+  static LEDState nextState;
+
+  static unsigned long lastUDPUpdate = 0;
+
+  LEDState lastState = ledState;
+
+  switch(ledState) {
+    case ANIMATION:
+      Serial.print("A");
+
+      if(stateEntered) {
+        animController.restart();
+      }
+
+      animController.loop();
+
+      if(animController.isIdle()) {
+        animController.changeAnimation(std::unique_ptr<Animation>(new FireAnimation(&ledFader, false)));
+      }
+
+      if(((WiFi.status() == WL_CONNECTED) || (WiFi.getMode() == WIFI_MODE_AP)) &&
+          udpProto.check()) {
+        // UDP packet received -> transition to UDP state
+        nextState = UDP;
+        ledState = TRANSITION;
+      }
+      break;
+
+    case UDP:
+      Serial.print("U");
+      if((WiFi.status() != WL_CONNECTED) && (WiFi.getMode() != WIFI_MODE_AP)) {
+        // WiFi disconnected -> switch to animation immediately to show reconnect animation
+        ledState = ANIMATION;
+        break;
+      }
+
+      if(udpProto.loop()) {
+        lastUDPUpdate = millis();
+        ledFader.update();
+      } else if(millis() - lastUDPUpdate > 3000) {
+        // seems like no more UDP data arrives -> transition to ANIMATION state
+        nextState = ANIMATION;
+        ledState = TRANSITION;
+      }
+      break;
+
+    case TRANSITION:
+      Serial.print("T");
+      if(stateEntered) {
+        ledFader.set_fadestep(2);
+        ledFader.fade_color(Fader::Color{0, 0, 0, 0});
+      }
+
+      ledFader.update();
+      if(!ledFader.something_changed()) {
+        // transition finished
+        ledState = nextState;
+        lastUDPUpdate = millis();
+      }
+
+      break;
+  }
+
+  stateEntered = (lastState != ledState);
+}
+
 static void ledTask( void * parameter )
 {
   uint64_t frame = 0;
@@ -96,15 +172,7 @@ static void ledTask( void * parameter )
 
     uint32_t start_time = micros();
 
-    animController.loop();
-
-    if(animController.isIdle()) {
-      animController.changeAnimation(std::unique_ptr<Animation>(new FireAnimation(&ledFader, false)));
-    }
-
-    if((WiFi.status() == WL_CONNECTED) || (WiFi.getMode() == WIFI_MODE_AP)) {
-      udpProto.loop();
-    }
+    ledFSM();
 
     led_idx++;
     if(led_idx >= STRANDS[0].numPixels) {
@@ -117,10 +185,6 @@ static void ledTask( void * parameter )
       strands[i] = &STRANDS[i];
     }
 
-    if(animController.isIdle()) {
-      ledFader.update();
-    }
-
     if(ledFader.something_changed()) {
       const std::vector<Fader::Color> &colors = ledFader.get_color_values();