fix: reject duplicate FieldID on add-new-field instead of silently overwriting

src/admin/fields.php

@@ -230,7 +230,14 @@
 		// Everything was alright, go and check if the entry exists!
 		$result = DB_Query("SELECT FieldID FROM " . DB_FIELDS . " WHERE FieldID = '" . $content['FieldID'] . "'");
 		$myrow = DB_GetSingleRow($result, true);
-		if ( !isset($myrow['FieldID']) )
+
+		if ( $_POST['op'] == "addnewfield" && isset($myrow['FieldID']) )
+		{
+			// Duplicate FieldID submitted via the add-new-field form — reject it.
+			$content['ISERROR'] = true;
+			$content['ERROR_MSG'] = GetAndReplaceLangStr( $content['LN_FIELDS_ERROR_FIELDIDEXISTS'], $content['FieldID'] );
+		}
+		else if ( !isset($myrow['FieldID']) )
 		{
 			//TODO: Trunscate NOT USED YET, it is currently set to 30 to avoid error mysql.
 			//		check "parsers.php" when using Truncate

src/lang/de/admin.php

@@ -355,6 +355,7 @@
 $content['LN_FIELDS_ERROR_FIELDIDEMPTY'] = "Die ID des Feldes war leer. ";
 $content['LN_FIELDS_ERROR_SEARCHFIELDEMPTY'] = "Der Suchfilter war leer. ";
 $content['LN_FIELDS_ERROR_FIELDDEFINEEMPTY'] = "Die interne Feld-ID war leer. ";
+$content['LN_FIELDS_ERROR_FIELDIDEXISTS'] = "Ein Feld mit der Feld-ID '%1' existiert bereits. Verwenden Sie die Bearbeiten-Funktion, um ein vorhandenes Feld zu ändern.";
 $content['LN_FIELDS_HASBEENEDIT'] = "Die Konfiguration des Feldes %1' wurde erfolgreich geÄndert.";
 $content['LN_FIELDS_HASBEENADDED'] = "Die Konfiguration des Feldes '%1' wurde erfolgreich hinzugefügt.";
 $content['LN_FIELDS_'] = "";

src/lang/en/admin.php

@@ -374,6 +374,7 @@
 $content['LN_FIELDS_ERROR_FIELDIDEMPTY'] = "The field id was empty. ";
 $content['LN_FIELDS_ERROR_SEARCHFIELDEMPTY'] = "The searchfilter was empty. ";
 $content['LN_FIELDS_ERROR_FIELDDEFINEEMPTY'] = "The internal FieldID was empty. ";
+$content['LN_FIELDS_ERROR_FIELDIDEXISTS'] = "A field with the FieldID '%1' already exists. Use the edit function to modify an existing field.";
 $content['LN_FIELDS_HASBEENEDIT'] = "The configuration for the field '%1' has been successfully edited.";
 $content['LN_FIELDS_HASBEENADDED'] = "The configuration for the field '%1' has been successfully added.";
 $content['LN_FIELDS_'] = "";

src/lang/es/admin.php

@@ -367,6 +367,7 @@
 $content['LN_FIELDS_ERROR_FIELDIDEMPTY'] = "La ID del Campo estaba vacía. ";
 $content['LN_FIELDS_ERROR_SEARCHFIELDEMPTY'] = "El Filtro de Búsqueda estaba vacío. ";
 $content['LN_FIELDS_ERROR_FIELDDEFINEEMPTY'] = "El ID Interno estaba vacío. ";
+$content['LN_FIELDS_ERROR_FIELDIDEXISTS'] = "Ya existe un campo con el ID de campo '%1'. Use la función de edición para modificar un campo existente.";
 $content['LN_FIELDS_HASBEENEDIT'] = "La configuración para el Campo '%1' se ha editado correctamente.";
 $content['LN_FIELDS_HASBEENADDED'] = "La configuración para el Campo '%1' se ha agregado con éxito.";
 $content['LN_FIELDS_'] = "";

src/lang/ja/admin.php

@@ -370,6 +370,7 @@
 $content['LN_FIELDS_ERROR_FIELDIDEMPTY'] = "The field id was empty. ";
 $content['LN_FIELDS_ERROR_SEARCHFIELDEMPTY'] = "The searchfilter was empty. ";
 $content['LN_FIELDS_ERROR_FIELDDEFINEEMPTY'] = "The internal FieldID was empty. ";
+$content['LN_FIELDS_ERROR_FIELDIDEXISTS'] = "A field with the FieldID '%1' already exists. Use the edit function to modify an existing field.";
 $content['LN_FIELDS_HASBEENEDIT'] = "The configuration for the field '%1' has been successfully edited.";
 $content['LN_FIELDS_HASBEENADDED'] = "The configuration for the field '%1' has been successfully added.";
 $content['LN_FIELDS_'] = "";