Implement folder move restrictions in file explorer and backend; prevent moving a folder into itself or its own subfolder.

go_cloud/internal/http/routes.go

@@ -1464,6 +1464,20 @@ func moveOrgFileHandler(w http.ResponseWriter, r *http.Request, db *database.DB,
 		return
 	}
 
+	// Prevent moving a folder into itself or its own subfolders
+	if sourceFile.Type == "folder" {
+		// Check if trying to move into itself
+		if req.SourcePath == req.TargetPath {
+			errors.WriteError(w, errors.CodeInvalidArgument, "Cannot move a folder into itself", http.StatusBadRequest)
+			return
+		}
+		// Check if target is a subfolder of source
+		if strings.HasPrefix(req.TargetPath, req.SourcePath+"/") {
+			errors.WriteError(w, errors.CodeInvalidArgument, "Cannot move a folder into its own subfolder", http.StatusBadRequest)
+			return
+		}
+	}
+
 	// Determine new file name - check if target is a folder
 	var newPath string
 	var targetFile *database.File
@@ -1670,6 +1684,20 @@ func moveUserFileHandler(w http.ResponseWriter, r *http.Request, db *database.DB
 		return
 	}
 
+	// Prevent moving a folder into itself or its own subfolders
+	if sourceFile.Type == "folder" {
+		// Check if trying to move into itself
+		if req.SourcePath == req.TargetPath {
+			errors.WriteError(w, errors.CodeInvalidArgument, "Cannot move a folder into itself", http.StatusBadRequest)
+			return
+		}
+		// Check if target is a subfolder of source
+		if strings.HasPrefix(req.TargetPath, req.SourcePath+"/") {
+			errors.WriteError(w, errors.CodeInvalidArgument, "Cannot move a folder into its own subfolder", http.StatusBadRequest)
+			return
+		}
+	}
+
 	// Determine new file name - check if target is a folder
 	var newPath string
 	var targetFile *database.File