fixed several crashes

src/DirectoryNode.cpp

@@ -167,6 +167,19 @@ void DirectoryNode::advanceToFirstMP3InThisNode()
 
 DirectoryNode *DirectoryNode::advanceToMP3(const uint16_t id)
 {
+
+
+    for (size_t i = 0; i < ids.size(); i++)
+        {
+            if (id == ids[i])
+            {
+                // Found the current MP3 file
+                currentPlaying = &mp3Files[i];
+                currentPlayingId = id;
+                return this;
+            }
+        }
+
     for (auto subdir : subdirectories)
     {
         if (subdir->getId() == id)
@@ -181,12 +194,9 @@ DirectoryNode *DirectoryNode::advanceToMP3(const uint16_t id)
             if (id == subdir->ids[i])
             {
                 // Found the current MP3 file
-                if (i < subdir->mp3Files.size() - 1)
+                subdir->currentPlaying = &subdir->mp3Files[i];
-                {
+                subdir->currentPlayingId = id;
-                    subdir->currentPlaying = &subdir->mp3Files[i];
+                return subdir;
-                    subdir->currentPlayingId = id;
-                    return subdir;
-                }
             }
         }
     }

src/main.cpp

@@ -64,7 +64,7 @@ DNSServer dns;
 uint16_t DirectoryNode::idCounter = 0;
 
 DirectoryNode rootNode("/");
-DirectoryNode *currentNode = NULL;
+DirectoryNode *currentNode = nullptr;
 
 
 
@@ -124,13 +124,25 @@ uint32_t getBatteryVoltageMv() {
 void playSongById(uint16_t id, uint32_t continueSeconds = 0)
 {
   currentNode = rootNode.advanceToMP3(id);
+
+  if (currentNode==nullptr) {    
+    return;
+  }
+
   String mp3File = currentNode->getCurrentPlayingFilePath();
   Serial.print("playing by id: ");
   Serial.print(id);Serial.print(" ");Serial.println(continueSeconds);
-
+  
   Serial.println(mp3File.c_str());
   deactivateRFID();
   activateSD();
+
+  if (currentNode != nullptr && currentNode->getCurrentPlaying()==nullptr) {
+    currentNode = nullptr;
+    Serial.println("no node by id found, exiting playSongById");
+    return;
+  }
+
   playFile(mp3File.c_str());
   if (continueSeconds!=0) {
     audio.setAudioPlayPosition(continueSeconds);
@@ -178,6 +190,10 @@ void playSongByRFID(String id)
  */
 bool playFile(const char *filename, uint32_t resumeFilePos)
 {
+  if (filename == nullptr || strlen(filename)==0) {
+    Serial.println("filename is empty.");
+    return false;
+  }
   return audio.connecttoSD(filename, resumeFilePos);
 }
 
@@ -206,7 +222,7 @@ void playNextMp3()
   Serial.print("Now advancing to ");
   String mp3File = currentNode->getCurrentPlayingFilePath();
   Serial.println(mp3File.c_str());
-  deactivateRFID();
+   deactivateRFID();
   activateSD();
   playFile(mp3File.c_str());
   activateRFID();
@@ -270,7 +286,8 @@ String getState()
 {
   DynamicJsonDocument jsonState(1024);
   jsonState["playing"] = audio.isRunning();
-  if (currentNode != NULL)
+
+  if (currentNode != nullptr)
     jsonState["title"] = *currentNode->getCurrentPlaying();
   else
     jsonState["title"] = "Angehalten";
@@ -367,12 +384,12 @@ void next()
 
 void previous()
 {
-    if (currentNode != nullptr) {
+    if (currentNode != NULL) {
         
         const String* curr = currentNode->getCurrentPlaying();
         DirectoryNode* newNode = currentNode->goToPreviousMP3();
         
-        if (newNode != nullptr) {
+        if (newNode != NULL) {
             if (curr == newNode->getCurrentPlaying()) {
               // reset to 0 seconds playtime:
               audio.setAudioPlayPosition(0);
@@ -510,6 +527,8 @@ void setup()
   Serial.println("Deactivating Brownout detector...");
   WRITE_PERI_REG(RTC_CNTL_BROWN_OUT_REG, 0); //disable brownout detector
 
+  //wifiManager.resetSettings();
+
   if (wifiManager.autoConnect("HannaBox"))
   {
     server.on("/", HTTP_GET, [](AsyncWebServerRequest *request)
@@ -645,7 +664,7 @@ void loop()
     deactivateRFID();
     activateSD();
     audio.loop();
-    if (currentNode != NULL && !prepareSleepMode)
+    if (currentNode != nullptr && !prepareSleepMode)
     {
       currentNode->setSecondsPlayed(audio.getAudioCurrentTime());
     }