It's working more or less...

include/controller.h

@@ -1,13 +1,25 @@
 #pragma once
 
 #include <Arduino.h>
+#include <MFRC522v2.h>
+#include <MFRC522Debug.h>
+#include "esmp3.h"
+#include "playlist.h"
 
 class Controller {
 	private:
 	void handle_buttons();
 	void handle_rfid();
+	bool is_button_pressed(uint8_t pin);
+	Playlist current_playlist;
+	bool is_rfid_present = false;
+	unsigned long last_rfid_check = 0;
 
 	public:
 	void handle();
-	
+	void next_track();
+	void prev_track();
+	void play();
+	void play(String rfid_id);
+	void stop();
 };

include/esmp3.h

@@ -1,11 +1,26 @@
 #pragma once
-#include "controller.h"
 
-#define PIN_CS_SD     16
-#define PIN_CS_RFID   17
+#include "controller.h"
+#include "playlist_manager.h"
+#include <Audio.h>
+
+#define PIN_CS_SD     22
+#define PIN_CS_RFID   21
+
+#define PIN_BTN_VOL_UP 32
+#define PIN_BTN_VOL_DOWN 33
+#define PIN_BTN_TRACK_NEXT 34
+#define PIN_BTN_TRACK_PREV 35
 
 #define I2S_DOUT      25
-#define I2S_BCLK      27
-#define I2S_LRC       26
+#define I2S_BCLK      26
+#define I2S_LRC       27
 
-extern Controller controller;
+class Controller;
+
+extern Controller controller;
+extern Audio audio;
+extern PlaylistManager* pm;
+extern MFRC522* rfid;
+
+void save_audio_current_time();

include/playlist.h

@@ -7,9 +7,19 @@ class Playlist {
 	private:
 	std::vector<String> files;
 	uint8_t current_file = 0;
-	uint16_t current_time = 0;
+	uint32_t current_time = 0;
+	void set_current_position(uint8_t file, uint32_t position=0);
+	String rfid_id;
 
 	public:
+	Playlist(String rfid_id="");
 	void add_file(String filename);
 	void sort();
+	String get_rfid_id();
+	String get_current_file_name();
+	bool next_track();
+	bool prev_track();
+	void restart();
+	void set_current_time(uint32_t time);
+	uint32_t get_current_time();
 };

include/playlist_manager.h

@@ -16,6 +16,7 @@ class PlaylistManager {
 	std::vector<String> dirs;
 	std::map<String, String> map;
 	Playlist get_playlist(String rfid_id);
+	bool has_playlist(String rfid_id);
 	Playlist current_playlist;
 	void set_audio_current_time(uint32_t time);
 };

platformio.ini

@@ -18,14 +18,16 @@ lib_deps =
 platform = espressif32
 board = esp-wrover-kit
 framework = arduino
-upload_speed = 115200
-build_flags = !./build_version.sh
+upload_speed = 921600
+build_flags = -DCORE_DEBUG_LEVEL=5 -DCONFIG_ARDUHAL_LOG_COLORS=1 ; !./build_version.sh
 lib_deps = 
 	${extra.lib_deps}
 	esphome/ESP32-audioI2S@^2.1.0
-upload_port = 10.10.2.108
+	computer991/Arduino_MFRC522v2@^2.0.1
+;upload_port = 10.10.2.108
 monitor_speed = 115200
 monitor_port = /dev/cu.usbserial-0001
+monitor_filters = time, esp32_exception_decoder
 
 [env:deploy]
 platform = espressif32
@@ -34,5 +36,6 @@ framework = arduino
 lib_deps = 
 	${extra.lib_deps}
 	esphome/ESP32-audioI2S@^2.1.0
+	computer991/Arduino_MFRC522v2@^2.0.1
 board_build.embed_txtfiles = src/index.html
 board_build.partitions = partitions.csv

src/controller.cpp

@@ -1,13 +1,100 @@
 #include "controller.h"
+#include "esmp3.h"
 
 void Controller::handle() {
-
+	if (last_rfid_check + 500 < millis() || last_rfid_check > millis()) {
+		handle_rfid();
+		last_rfid_check = millis();
+	}
 }
 
 void Controller::handle_buttons() {
-
+	if (is_button_pressed(PIN_BTN_VOL_UP)) {
+		audio.setVolume(min(audio.getVolume()+1, 21));
+	} else if (is_button_pressed(PIN_BTN_VOL_DOWN)) {
+		audio.setVolume(max(audio.getVolume()-1, 1));
+	} else if (is_button_pressed(PIN_BTN_TRACK_NEXT)) {
+		next_track();
+	} else if (is_button_pressed(PIN_BTN_TRACK_PREV)) {
+		prev_track();
+	}
 }
 
 void Controller::handle_rfid() {
-	
+	if (is_rfid_present) {
+		byte buffer[2];
+		byte buffer_size = 2;
+		MFRC522Constants::StatusCode status = rfid->PICC_WakeupA(buffer, &buffer_size);
+		if (status == MFRC522Constants::STATUS_OK) {
+			// Card is still present.
+			rfid->PICC_HaltA();
+		} else {
+			Serial.printf("RFID status is %s\n", MFRC522Debug::GetStatusCodeName(status));
+			is_rfid_present = false;
+			Serial.println("No more RFID card.\n");
+			stop();
+		}
+	} else {
+		if (rfid->PICC_IsNewCardPresent()) {
+			if (rfid->PICC_ReadCardSerial()) {
+				uint32_t uid = rfid->uid.uidByte[0]<<24 | rfid->uid.uidByte[1]<<16 | rfid->uid.uidByte[2]<<8 | rfid->uid.uidByte[3];
+				Serial.printf("Found new rfid card with uid %x\n", uid);
+				is_rfid_present = true;
+				if (uid > 0) {
+					String temp = String(uid, HEX);
+					String s_uid = "";
+					for (int i=0; i<(8-temp.length()); i++) {
+						s_uid.concat("0");
+					}
+					s_uid.concat(temp);
+					play(s_uid);
+				}
+				rfid->PICC_HaltA();
+			}
+		}
+	}
+}
+
+void Controller::play(String rfid_id) {
+	if (!rfid_id.equals(current_playlist.get_rfid_id())) {
+		if (pm->has_playlist(rfid_id)) {
+			current_playlist = pm->get_playlist(rfid_id);
+			play();
+		} else {
+			Serial.printf("There is no playlist for rfid_id %s\n", rfid_id.c_str());
+		}
+	} else {
+		if (!audio.isRunning()) {
+			play();
+		}
+	}
+}
+
+void Controller::play() {
+	String file = current_playlist.get_current_file_name();
+	Serial.printf("Playing file: %s\n", file.c_str());
+	audio.connecttoFS(SD, file.c_str(), current_playlist.get_current_time());
+}
+
+void Controller::next_track() {
+	if (current_playlist.next_track()) {
+		play();
+	}
+}
+
+void Controller::prev_track() {
+	if (audio.getAudioCurrentTime() <= 5) {
+		current_playlist.restart();
+		play();
+	} else {
+		if (current_playlist.prev_track()) {
+			play();
+		}
+	}
+}
+
+void Controller::stop() {
+	if (audio.isRunning()) {
+		current_playlist.set_current_time(audio.stopSong());
+	}
 }

src/esmp3.cpp

@@ -7,33 +7,53 @@
 #include <Audio.h>
 #include "esmp3.h"
 #include <Ticker.h>
+#include <MFRC522v2.h>
+#include <MFRC522DriverSPI.h>
+#include <MFRC522DriverPinSimple.h>
+#include <MFRC522Debug.h>
+#include <Arduino.h>
+#include <Wire.h>
 
 Controller controller;
 Audio audio;
-Ticker ticker_save_audio_current_time;
 PlaylistManager* pm;
+MFRC522* rfid;
 
 void setup() {
+	pinMode(PIN_CS_SD, OUTPUT);		digitalWrite(PIN_CS_SD, HIGH);
+	pinMode(PIN_CS_RFID, OUTPUT);	digitalWrite(PIN_CS_RFID, HIGH);
 	Serial.begin(115200);
 	WiFi.begin("Schlenz", "1410WischlingenPanda");
-	Serial.print("Connecting to WiFi...");
+	log_i("Connecting to WiFi...");
+	uint8_t i=9;
 	while(WiFi.status() != WL_CONNECTED) {
-		Serial.print(".");
-		delay(500);
+		Serial.print(i);
+		Serial.print("... ");
+		delay(1000);
+		i--;
+		if (i==0) {
+			Serial.println("Could not connect to WiFi. Restarting in 1s.");
+			delay(1000);
+			ESP.restart();
+		}
 	}
 	Serial.println();
 	Serial.print("Connected to WiFi. IP address: ");
 	Serial.println(WiFi.localIP());
-
 	ArduinoOTA.begin();
+	Serial.println("Waiting for OTA...");
+	for(int i=0; i<20; i++) {
+		ArduinoOTA.handle();
+		delay(100);
+	}
 	Serial.println("Initializing SPI...");
 	SPI.begin();
-	SPI.setHwCs(false);
-	SPIMaster::initialize();
+	//SPI.setHwCs(false);
+	//SPIMaster::initialize();
 
 	Serial.print("Initializing SD card...");
-	SPIMaster::enable_sd();
-	while(!SD.begin(14, SPI, 25000000)) {
+	//SPIMaster::enable_sd();
+	while(!SD.begin(PIN_CS_SD, SPI, 25000000)) {
 		for(int i=0; i<10; i++) {
 			if(SPI.transfer(0xFF)==0xFF) break;
 			delay(10);
@@ -46,15 +66,29 @@ void setup() {
 	Serial.println("Initializing PlaylistManager...");
 	pm = new PlaylistManager();
 
+	Serial.println("Setting up rfid reader...");
+	pinMode(PIN_CS_RFID, OUTPUT);
+	MFRC522DriverPin* pin = new MFRC522DriverPinSimple(PIN_CS_RFID);
+	MFRC522Driver* spi = new MFRC522DriverSPI(*pin);
+	rfid = new MFRC522(*spi);
+	rfid->PCD_Init();
+	MFRC522Debug::PCD_DumpVersionToSerial(*rfid, Serial);
+
+	Serial.println("Setting up buttons...");
+	pinMode(PIN_BTN_VOL_UP, INPUT_PULLUP);
+	pinMode(PIN_BTN_VOL_DOWN, INPUT_PULLUP);
+	pinMode(PIN_BTN_TRACK_NEXT, INPUT_PULLUP);
+	pinMode(PIN_BTN_TRACK_PREV, INPUT_PULLUP);
+
 	Serial.println("Setting up audio...");
 	audio.setPinout(I2S_BCLK, I2S_LRC, I2S_DOUT);
 	audio.setVolume(15);
 	audio.forceMono(true);
 
-	Serial.println("Setting up tickers...");
-	ticker_save_audio_current_time.attach(5, save_audio_current_time);
-
 	Serial.println("Setup finished.");
+
+	audio.setVolume(3);
+	audio.connecttospeech("Die Papabox ist nun einsatzbereit!", "de_DE");
 }
 
 void loop() {
@@ -63,6 +97,34 @@ void loop() {
 	audio.loop();
 }
 
-void save_audio_current_time() {
-	pm->set_audio_current_time(audio.getAudioCurrentTime());
-}
+void audio_info(const char *info){
+    Serial.print("info        "); Serial.println(info);
+}
+void audio_id3data(const char *info){  //id3 metadata
+    Serial.print("id3data     ");Serial.println(info);
+}
+void audio_eof_mp3(const char *info){  //end of file
+    Serial.print("eof_mp3     ");Serial.println(info);
+	controller.next_track();
+}
+void audio_showstation(const char *info){
+    Serial.print("station     ");Serial.println(info);
+}
+void audio_showstreamtitle(const char *info){
+    Serial.print("streamtitle ");Serial.println(info);
+}
+void audio_bitrate(const char *info){
+    Serial.print("bitrate     ");Serial.println(info);
+}
+void audio_commercial(const char *info){  //duration in sec
+    Serial.print("commercial  ");Serial.println(info);
+}
+void audio_icyurl(const char *info){  //homepage
+    Serial.print("icyurl      ");Serial.println(info);
+}
+void audio_lasthost(const char *info){  //stream URL played
+    Serial.print("lasthost    ");Serial.println(info);
+}
+void audio_eof_speech(const char *info){
+    Serial.print("eof_speech  ");Serial.println(info);
+}

src/playlist.cpp

@@ -1,9 +1,61 @@
 #include "playlist.h"
 
+Playlist::Playlist(String id) {
+	rfid_id = id;
+}
+
+String Playlist::get_rfid_id() {
+	return rfid_id;
+}
+
 void Playlist::add_file(String filename) {
 	files.push_back(filename);
 }
 
 void Playlist::sort() {
 	std::sort(files.begin(), files.end());
+}
+
+void Playlist::set_current_position(uint8_t file, uint32_t seconds) {
+	current_file = file;
+	current_time = seconds;
+}
+
+String Playlist::get_current_file_name() {
+	if (current_file >= files.size()) {
+		Serial.printf("Requested a file number %d, which is not available in this playlist. Starting over.\n", current_file);
+		set_current_position(0);
+	}
+	return files[current_file];
+}
+
+bool Playlist::next_track() {
+	if (files.size() <= current_file + 1) {
+		Serial.println("next_track does not exist. Resetting playlist and returning false.");
+		set_current_position(0, 0);
+		return false;
+	}
+	set_current_position(current_file + 1, 0);
+	return true;
+}
+
+bool Playlist::prev_track() {
+	if (current_file == 0) {
+		return false;
+	}
+	
+	set_current_position(current_file - 1, 0);
+	return true;
+}
+
+void Playlist::restart() {
+	current_time = 0;
+}
+
+void Playlist::set_current_time(uint32_t pos) {
+	current_time = pos;
+}
+
+uint32_t Playlist::get_current_time() {
+	return current_time;
 }

src/playlist_manager.cpp

@@ -64,18 +64,18 @@ Playlist PlaylistManager::get_playlist(String rfid_id) {
 			Serial.printf("No known playlist for id %s.\n", rfid_id);
 			return current_playlist;
 		} else {
-			current_playlist = Playlist();
-			String entry = map[rfid_id];
-			if (entry.startsWith("/")) {
-				File dir = SD.open(entry);
+			current_playlist = Playlist(rfid_id);
+			String path = map[rfid_id];
+			if (path.startsWith("/")) {
+				File dir = SD.open(path);
 				while(File entry = dir.openNextFile()) {
 					String filename = entry.name();
 					String ext = filename.substring(filename.length()-4);
 					if (!entry.isDirectory() &&
 						!filename.startsWith(".") &&
 						ext.equals(".mp3")) {
-						Serial.printf("Adding %s to the list of files\n", filename);
-						current_playlist.add_file(filename);
+						Serial.printf("Adding %s to the list of files\n", (path + "/" + filename).c_str());
+						current_playlist.add_file(path + "/" + filename);
 					}
 					entry.close();
 				}
@@ -90,4 +90,8 @@ Playlist PlaylistManager::get_playlist(String rfid_id) {
 
 void PlaylistManager::set_audio_current_time(uint32_t time) {
 	audio_current_time = time;
+}
+
+bool PlaylistManager::has_playlist(String rfid_id) {
+	return map.count(rfid_id) == 1;
 }