Added extractModeName() utility function.

wled00/fcn_declare.h

@@ -222,6 +222,7 @@ void sendSysInfoUDP();
 //bool isAsterisksOnly(const char* str, byte maxLen);
 bool requestJSONBufferLock(uint8_t module=255);
 void releaseJSONBufferLock();
+uint8_t extractModeName(uint8_t mode, const char *src, char *dest, uint8_t maxLen);
 
 //um_manager.cpp
 class Usermod {

wled00/util.cpp

@@ -31,3 +31,38 @@ void releaseJSONBufferLock()
   fileDoc = nullptr;
   jsonBufferLock = 0;
 }
+
+
+// extracts effect mode (or palette) name from names serialized string
+// caller must provide large enough buffer for name (incluing SR extensions)!
+uint8_t extractModeName(uint8_t mode, const char *src, char *dest, uint8_t maxLen)
+{
+  uint8_t qComma = 0;
+  bool insideQuotes = false;
+  uint8_t printedChars = 0;
+  char singleJsonSymbol;
+  size_t len = strlen_P(src);
+
+  // Find the mode name in JSON
+  for (size_t i = 0; i < len; i++) {
+    singleJsonSymbol = pgm_read_byte_near(src + i);
+    if (singleJsonSymbol == '\0') break;
+    if (singleJsonSymbol == '@' && insideQuotes && qComma == mode) break; //stop when SR extension encountered
+    switch (singleJsonSymbol) {
+      case '"':
+        insideQuotes = !insideQuotes;
+        break;
+      case '[':
+      case ']':
+        break;
+      case ',':
+        if (!insideQuotes) qComma++;
+      default:
+        if (!insideQuotes || (qComma != mode)) break;
+        dest[printedChars++] = singleJsonSymbol;
+    }
+    if ((qComma > mode) || (printedChars >= maxLen)) break;
+  }
+  dest[printedChars] = '\0';
+  return strlen(dest);
+}