fix: remove unused safeOpenFile function and improve file operations security

1. Removed unused safeOpenFile function

2. Updated file operations to use safeReadFile

3. Simplified tree node finding and sorting logic

4. Improved generated file detection

Author: kuhahalong

reader.go

@@ -98,47 +98,6 @@ func (r *DefaultReader) safeReadFile(path string) ([]byte, error) {
 	return os.ReadFile(absPath)
 }
 
-// safeOpenFile opens a file with security checks
-func (r *DefaultReader) safeOpenFile(path string) (*os.File, error) {
-	if err := r.validatePath(path); err != nil {
-		return nil, fmt.Errorf("invalid path: %w", err)
-	}
-
-	// Get absolute path
-	absPath := path
-	if !filepath.IsAbs(path) {
-		absPath = filepath.Join(r.workDir, path)
-	}
-
-	// Clean the path
-	absPath = filepath.Clean(absPath)
-
-	// Verify file exists and get info
-	info, err := os.Stat(absPath)
-	if err != nil {
-		return nil, err
-	}
-
-	// Check if it's a regular file
-	if !info.Mode().IsRegular() {
-		return nil, fmt.Errorf("not a regular file: %s", path)
-	}
-
-	// Check file size
-	if info.Size() > maxFileSize {
-		return nil, fmt.Errorf("file too large: %s", path)
-	}
-
-	// Check file extension for allowed types
-	ext := strings.ToLower(filepath.Ext(path))
-	if !isAllowedExtension(ext) {
-		return nil, fmt.Errorf("unsupported file type: %s", ext)
-	}
-
-	// Open file with read-only mode
-	return os.OpenFile(absPath, os.O_RDONLY, 0)
-}
-
 // GetFileTree returns the file tree starting from the given root
 func (r *DefaultReader) GetFileTree(ctx context.Context, root string, opts TreeOptions) (*FileTreeNode, error) {
 	if err := r.validatePath(root); err != nil {
@@ -205,7 +164,7 @@ func (r *DefaultReader) GetFileTree(ctx context.Context, root string, opts TreeO
 					return nil
 				}
 			case FileTypeGenerated:
-				content, err := os.ReadFile(path)
+				content, err := r.safeReadFile(path)
 				if err != nil {
 					return err
 				}
@@ -237,19 +196,16 @@ func (r *DefaultReader) GetFileTree(ctx context.Context, root string, opts TreeO
 		// Find parent node
 		if path != absRoot {
 			parentPath := filepath.Dir(relPath)
-			parent := findParentNode(tree, parentPath)
-			if parent != nil {
-				parent.Children = append(parent.Children, node)
-				sortTree(parent)
-				return nil
+			parentNode := findNode(tree, parentPath)
+			if parentNode != nil {
+				parentNode.Children = append(parentNode.Children, node)
+				// Sort children by name
+				sort.Slice(parentNode.Children, func(i, j int) bool {
+					return parentNode.Children[i].Name < parentNode.Children[j].Name
+				})
 			}
 		}
 
-		// If no parent found (should only happen for root), add to tree
-		if path == absRoot {
-			*tree = *node
-		}
-
 		return nil
 	})
 
@@ -371,57 +327,35 @@ func (r *DefaultReader) ReadSourceFile(ctx context.Context, path string, opts Re
 
 // isGeneratedFile checks if a file is generated based on its content
 func isGeneratedFile(content []byte) bool {
-	// Common markers for generated files
+	contentStr := string(content)
 	markers := []string{
-		"Code generated",
-		"DO NOT EDIT",
+		"Code generated", "DO NOT EDIT",
 		"@generated",
-		"Generated by",
+		"// Generated by",
+		"/* Generated by",
 	}
 
-	contentStr := string(content)
 	for _, marker := range markers {
 		if strings.Contains(contentStr, marker) {
 			return true
 		}
 	}
-
 	return false
 }
 
-// findParentNode finds a parent node in the tree by path
-func findParentNode(root *FileTreeNode, parentPath string) *FileTreeNode {
-	if root.Path == parentPath {
+// findNode finds a node in the tree by its path
+func findNode(root *FileTreeNode, path string) *FileTreeNode {
+	if root.Path == path {
 		return root
 	}
+
 	for _, child := range root.Children {
 		if child.Type == "directory" {
-			if node := findParentNode(child, parentPath); node != nil {
+			if node := findNode(child, path); node != nil {
 				return node
 			}
 		}
 	}
-	return nil
-}
 
-// sortTree sorts the children of a node by name
-func sortTree(node *FileTreeNode) {
-	if node == nil || len(node.Children) == 0 {
-		return
-	}
-
-	sort.Slice(node.Children, func(i, j int) bool {
-		// Directories come first
-		if node.Children[i].Type != node.Children[j].Type {
-			return node.Children[i].Type == "directory"
-		}
-		return node.Children[i].Name < node.Children[j].Name
-	})
-
-	// Sort children recursively
-	for _, child := range node.Children {
-		if child.Type == "directory" {
-			sortTree(child)
-		}
-	}
+	return nil
 }