Initial commit: Open sourcing all of the Maple Open Technologies code.

native/desktop/maplefile/internal/config/userdata.go

@@ -0,0 +1,175 @@
+// internal/config/userdata.go
+package config
+
+import (
+	"crypto/sha256"
+	"encoding/hex"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+)
+
+// GetUserDataDir returns the appropriate directory for storing application data
+// following platform-specific conventions:
+// - Windows: %LOCALAPPDATA%\{appName}
+// - macOS: ~/Library/Application Support/{appName}
+// - Linux: ~/.local/share/{appName} (or $XDG_DATA_HOME/{appName})
+func GetUserDataDir(appName string) (string, error) {
+	var baseDir string
+	var err error
+
+	switch runtime.GOOS {
+	case "windows":
+		// Use LOCALAPPDATA for application data on Windows
+		baseDir = os.Getenv("LOCALAPPDATA")
+		if baseDir == "" {
+			// Fallback to APPDATA if LOCALAPPDATA is not set
+			baseDir = os.Getenv("APPDATA")
+			if baseDir == "" {
+				// Last resort: use UserConfigDir
+				baseDir, err = os.UserConfigDir()
+				if err != nil {
+					return "", err
+				}
+			}
+		}
+
+	case "darwin":
+		// Use ~/Library/Application Support on macOS
+		home, err := os.UserHomeDir()
+		if err != nil {
+			return "", err
+		}
+		baseDir = filepath.Join(home, "Library", "Application Support")
+
+	default:
+		// Linux and other Unix-like systems
+		// Follow XDG Base Directory Specification
+		if xdgData := os.Getenv("XDG_DATA_HOME"); xdgData != "" {
+			baseDir = xdgData
+		} else {
+			home, err := os.UserHomeDir()
+			if err != nil {
+				return "", err
+			}
+			baseDir = filepath.Join(home, ".local", "share")
+		}
+	}
+
+	// Combine with app name
+	appDataDir := filepath.Join(baseDir, appName)
+
+	// Create the directory if it doesn't exist with restrictive permissions
+	if err := os.MkdirAll(appDataDir, 0700); err != nil {
+		return "", err
+	}
+
+	return appDataDir, nil
+}
+
+// GetUserSpecificDataDir returns the data directory for a specific user.
+// User data is isolated by hashing the email to create a unique directory name.
+// This ensures:
+// 1. Different users have completely separate storage
+// 2. Email addresses are not exposed in directory names
+// 3. The same user always gets the same directory
+//
+// Directory structure:
+//
+//	{appDataDir}/users/{emailHash}/
+//	  ├── local_files/    # File and collection metadata (LevelDB)
+//	  ├── sync_state/     # Sync state (LevelDB)
+//	  ├── cache/          # Application cache (LevelDB)
+//	  └── files/          # Downloaded decrypted files
+//	      └── {collectionId}/
+//	          └── {filename}
+func GetUserSpecificDataDir(appName, userEmail string) (string, error) {
+	if userEmail == "" {
+		return "", nil // No user logged in, return empty
+	}
+
+	appDataDir, err := GetUserDataDir(appName)
+	if err != nil {
+		return "", err
+	}
+
+	// Hash the email to create a privacy-preserving directory name
+	emailHash := hashEmail(userEmail)
+
+	// Create user-specific directory
+	userDir := filepath.Join(appDataDir, "users", emailHash)
+
+	// Create the directory with restrictive permissions (owner only)
+	if err := os.MkdirAll(userDir, 0700); err != nil {
+		return "", err
+	}
+
+	return userDir, nil
+}
+
+// GetUserFilesDir returns the directory where decrypted files are stored for a user.
+// Files are organized by collection: {userDir}/files/{collectionId}/{filename}
+func GetUserFilesDir(appName, userEmail string) (string, error) {
+	userDir, err := GetUserSpecificDataDir(appName, userEmail)
+	if err != nil {
+		return "", err
+	}
+	if userDir == "" {
+		return "", nil // No user logged in
+	}
+
+	filesDir := filepath.Join(userDir, "files")
+
+	// Create with restrictive permissions
+	if err := os.MkdirAll(filesDir, 0700); err != nil {
+		return "", err
+	}
+
+	return filesDir, nil
+}
+
+// hashEmail creates a SHA256 hash of the email address (lowercase, trimmed).
+// Returns a shortened hash (first 16 characters) for more readable directory names
+// while still maintaining uniqueness.
+func hashEmail(email string) string {
+	// Normalize email: lowercase and trim whitespace
+	normalizedEmail := strings.ToLower(strings.TrimSpace(email))
+
+	// Create SHA256 hash
+	hash := sha256.Sum256([]byte(normalizedEmail))
+
+	// Return first 16 characters of hex representation (64 bits of entropy is sufficient)
+	return hex.EncodeToString(hash[:])[:16]
+}
+
+// GetEmailHashForPath returns the hash that would be used for a user's directory.
+// This can be used to check if a user's data exists without revealing the email.
+func GetEmailHashForPath(userEmail string) string {
+	if userEmail == "" {
+		return ""
+	}
+	return hashEmail(userEmail)
+}
+
+// GetUserSearchIndexDir returns the directory where the Bleve search index is stored.
+// Returns: {userDir}/search/index.bleve
+func GetUserSearchIndexDir(appName, userEmail string) (string, error) {
+	userDir, err := GetUserSpecificDataDir(appName, userEmail)
+	if err != nil {
+		return "", err
+	}
+	if userDir == "" {
+		return "", nil // No user logged in
+	}
+
+	searchIndexPath := filepath.Join(userDir, "search", "index.bleve")
+
+	// Create parent directory with restrictive permissions
+	searchDir := filepath.Join(userDir, "search")
+	if err := os.MkdirAll(searchDir, 0700); err != nil {
+		return "", err
+	}
+
+	return searchIndexPath, nil
+}