add decoder polymorphism

src/mp3.cpp

@@ -57,6 +57,7 @@ void MP3::start() {
 }
 
 void MP3::mp3_decoder_task(void *pvParameters) {
+  strcpy(titleStr, "...");
   file = new AudioFileSourceICYStream(URL);
   file->RegisterMetadataCB(MDCallback, (void*)"ICY");
   buff = new AudioFileSourceBuffer(file, preallocateBuffer, preallocateBufferSize);
@@ -65,31 +66,32 @@ void MP3::mp3_decoder_task(void *pvParameters) {
     out = new AudioOutputI2S(I2S_NUM_0, false, 0);
     out->SetPinout(12, 13, 25);
   }
-  mp3 = new AudioGeneratorMP3();
-  mp3->RegisterStatusCB(StatusCallback, (void*)"mp3");
-  mp3->begin(buff, out);
+  decoder = new AudioGeneratorMP3();
+  decoder->RegisterStatusCB(StatusCallback, (void*)"mp3");
+  decoder->begin(buff, out);
   out->SetGain(1.0);
   playing = true;
 
-  while(mp3->isRunning()) {
+  while(decoder->isRunning()) {
     if (millis()-lastms > 1000) {
       lastms = millis();
       Serial.printf("Running for %d ms...\n", lastms);
       Serial.flush();
     }
-    if (!mp3->loop()) break;
+    if (!decoder->loop()) break;
     if (!playing) break;
     vTaskDelay(5 / portTICK_PERIOD_MS);
   }
 
   Serial.printf("MP3 done\n");
+  strcpy(titleStr, "___");
 
   playing = false;
 
-  if (mp3) {
-    mp3->stop();
-    delete mp3;
-    mp3 = NULL;
+  if (decoder) {
+    decoder->stop();
+    delete decoder;
+    decoder = NULL;
   }
   if (buff) {
     buff->close();

src/mp3.h

@@ -22,7 +22,7 @@ class MP3 {
     void start(void);
     bool playing = false;
   private:
-    AudioGeneratorMP3 *mp3;
+    AudioGenerator *decoder;
     AudioFileSourceICYStream *file;
     AudioFileSourceBuffer *buff;
     AudioOutputI2S *out;