Initial commit: Phase 1+2 prototype

- Go backend with SQLite, JWT auth, file CRUD
- Vue 3 frontend with split/raw/WYSIWYG editor modes
- Markdown preview (marked, GFM)
- Formatting toolbar + keyboard shortcuts
- File tree with search, create, delete
- Light/dark theme toggle
- Admin panel (user management)
- Preferences (timezone, theme, default mode)
- Shared documents section (placeholder)
- Export: PDF, HTML, MD
- Build daemon (Python, stdlib only)
- Build job queue API
- Docker deployment

internal/files/files.go

@@ -0,0 +1,124 @@
+package files
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+type FileInfo struct {
+	Name  string     `json:"name"`
+	Path  string     `json:"path"`
+	IsDir bool       `json:"isDir"`
+	Children []FileInfo `json:"children,omitempty"`
+}
+
+// UserDir returns the base directory for a user's files.
+func UserDir(dataDir, userID string) string {
+	return filepath.Join(dataDir, "files", userID)
+}
+
+// EnsureUserDir creates the user's file directory if it doesn't exist.
+func EnsureUserDir(dataDir, userID string) error {
+	return os.MkdirAll(UserDir(dataDir, userID), 0755)
+}
+
+// ReadFile reads a markdown file for a user.
+func ReadFile(dataDir, userID, relPath string) (string, error) {
+	p := safePath(dataDir, userID, relPath)
+	if p == "" {
+		return "", os.ErrPermission
+	}
+	b, err := os.ReadFile(p)
+	return string(b), err
+}
+
+// WriteFile writes content to a markdown file for a user.
+func WriteFile(dataDir, userID, relPath, content string) error {
+	p := safePath(dataDir, userID, relPath)
+	if p == "" {
+		return os.ErrPermission
+	}
+	if err := os.MkdirAll(filepath.Dir(p), 0755); err != nil {
+		return err
+	}
+	return os.WriteFile(p, []byte(content), 0644)
+}
+
+// CreateFolder creates a directory for a user.
+func CreateFolder(dataDir, userID, relPath string) error {
+	p := safePath(dataDir, userID, relPath)
+	if p == "" {
+		return os.ErrPermission
+	}
+	return os.MkdirAll(p, 0755)
+}
+
+// DeleteFile removes a file or folder for a user.
+func DeleteFile(dataDir, userID, relPath string) error {
+	p := safePath(dataDir, userID, relPath)
+	if p == "" {
+		return os.ErrPermission
+	}
+	return os.RemoveAll(p)
+}
+
+// ListTree returns the file tree for a user.
+func ListTree(dataDir, userID string) ([]FileInfo, error) {
+	root := UserDir(dataDir, userID)
+	if err := os.MkdirAll(root, 0755); err != nil {
+		return nil, err
+	}
+	return listDir(root, "")
+}
+
+func listDir(base, rel string) ([]FileInfo, error) {
+	dir := filepath.Join(base, rel)
+	entries, err := os.ReadDir(dir)
+	if err != nil {
+		return nil, err
+	}
+	var result []FileInfo
+	for _, e := range entries {
+		entryRel := filepath.Join(rel, e.Name())
+		info := FileInfo{
+			Name:  e.Name(),
+			Path:  entryRel,
+			IsDir: e.IsDir(),
+		}
+		if e.IsDir() {
+			children, err := listDir(base, entryRel)
+			if err == nil {
+				info.Children = children
+			}
+		}
+		result = append(result, info)
+	}
+	return result, nil
+}
+
+// safePath validates and returns the absolute path, preventing traversal.
+func safePath(dataDir, userID, relPath string) string {
+	if strings.Contains(relPath, "..") {
+		return ""
+	}
+	root := UserDir(dataDir, userID)
+	p := filepath.Join(root, filepath.Clean(relPath))
+	if !strings.HasPrefix(p, root) {
+		return ""
+	}
+	return p
+}
+
+// GetCreatedTime returns the file's modification time as ISO string.
+func GetCreatedTime(dataDir, userID, relPath string) string {
+	p := safePath(dataDir, userID, relPath)
+	if p == "" {
+		return ""
+	}
+	info, err := os.Stat(p)
+	if err != nil {
+		return ""
+	}
+	return info.ModTime().UTC().Format("2006-01-02T15:04:05Z")
+}