[ai] Memory Optimizations

platformio.ini

@@ -19,8 +19,8 @@ lib_deps =
 monitor_speed = 115200
 build_flags = 
     -Os                                   ; Optimize for size
-;   -DDEBUG                               ; Hannabox Debugging
+   -DDEBUG                               ; Hannabox Debugging
-   -DCORE_DEBUG_LEVEL=0                  ; Disable all debug output
+;   -DCORE_DEBUG_LEVEL=0                  ; Disable all debug output
 ;   -DARDUINO_LOOP_STACK_SIZE=4096        ; Balanced to avoid stack canary without starving heap
 ;   -DWIFI_TASK_STACK_SIZE=3072           ; Reduce WiFi task stack
 ;   -DARDUINO_EVENT_TASK_STACK_SIZE=2048  ; Reduce event task stack

src/DirectoryNode.cpp

@@ -405,11 +405,11 @@ DirectoryNode *DirectoryNode::advanceToMP3(const String &songName)
         }
         else
         {
-            // Use static buffer for case conversion and comparison
+            // Use static buffer for comparison without allocation
             buildFullPath(mp3Files[i], buffer, buffer_size);
-            String f = String(buffer);
+            size_t bufLen = strlen(buffer);
-            f.toLowerCase();
+            size_t targetLen = lowTarget.length();
-            if (f.endsWith(lowTarget))
+            if (bufLen >= targetLen && strcasecmp(buffer + bufLen - targetLen, lowTarget.c_str()) == 0)
             {
                 setCurrentPlaying(mp3Files[i]);
                 return this;
@@ -450,9 +450,11 @@ DirectoryNode *DirectoryNode::advanceToMP3(const String &songName)
             }
             else
             {
-                String f = subdir->mp3Files[i];
+                // Check suffix case-insensitively without creating new Strings
-                f.toLowerCase();
+                const String& fName = subdir->mp3Files[i];
-                if (f.endsWith(lowTarget))
+                size_t fLen = fName.length();
+                size_t targetLen = lowTarget.length();
+                if (fLen >= targetLen && strcasecmp(fName.c_str() + fLen - targetLen, lowTarget.c_str()) == 0)
                 {
                     subdir->setCurrentPlaying(subdir->mp3Files[i]);
                     return subdir;

src/main.cpp

@@ -147,10 +147,8 @@ void handleUpload(AsyncWebServerRequest *request, String filename, size_t index,
     activateSD();
 
     // Check if file already exists and create backup name if needed
-    String filepath;
+    char filepath[256];
-    filepath.reserve(1 + filename.length());
+    snprintf(filepath, sizeof(filepath), "/%s", filename.c_str());
-    filepath = "/";
-    filepath += filename;
     if (SD.exists(filepath))
     {
       request->send(500, txt_plain, F("File already exists."));
@@ -806,54 +804,6 @@ void readDataFromFile(const String &filename)
   }
 }
 
-String processor(const String &var)
-{
-
-  if (var == "MAPPING")
-  {
-    auto htmlEscape = [](const String &s) -> String
-    {
-      String out;
-      for (size_t i = 0; i < s.length(); ++i)
-      {
-        char c = s[i];
-        if (c == '&')
-          out += "&";
-        else if (c == '<')
-          out += "";
-        else if (c == '>')
-          out += "";
-        else if (c == '"')
-          out += "";
-        else if (c == '\'')
-          out += "";
-        else
-          out += c;
-      }
-      return out;
-    };
-    String html;
-    html.reserve(256);
-    html.concat(F("<table style='width:100%;border-collapse:collapse;'><tr><th style='border:1px solid #ccc;padding:4px;'>RFID</th><th style='border:1px solid #ccc;padding:4px;'>Song</th></tr>"));
-    for (const auto &pair : rfid_map)
-    {
-      html.concat(F("<tr><td style='border:1px solid #ccc;padding:4px;'>"));
-      html.concat(htmlEscape(pair.first));
-      html.concat(F("</td><td style='border:1px solid #ccc;padding:4px;'>"));
-      // Show target and mode (e.g. "mysong.mp3|s")
-      String mappingVal = pair.second.target;
-      mappingVal += "|";
-      mappingVal += pair.second.mode;
-      html.concat(htmlEscape(mappingVal));
-      html.concat(F("</td></tr>"));
-    }
-    html.concat(F("</table>"));
-    return html;
-  }
-
-  return String(); // Return empty string instead of creating new String
-}
-
 // Memory-optimized helpers and streamers to avoid large temporary Strings
 
 static inline void htmlEscapeAndPrint(Print &out, const String &s)
@@ -1565,8 +1515,8 @@ void setup()
   wifiManager.setDebugOutput(true);
 
   // Reduce timeouts to free memory faster
-  wifiManager.setTimeout(180);             // Reduced from 180
+  wifiManager.setTimeout(150);             // Reduced from 180
-  wifiManager.setConnectTimeout(20);      // Faster connection attempts
+  wifiManager.setConnectTimeout(30);      // Faster connection attempts
   wifiManager.setConfigPortalTimeout(120); // Shorter portal timeout
 
 #ifdef DEBUG