create dir

app.go

@@ -237,6 +237,10 @@ func (a *App) deleteShare(doc *Document) error {
 }
 
 func (a *App) writeConfig(doc *Document) error {
+	if err := a.ensureShareDirectories(doc); err != nil {
+		return err
+	}
+
 	backup := fmt.Sprintf("%s.bak.%s", a.configPath, time.Now().UTC().Format("20060102T150405Z"))
 	serialized := doc.Serialize()
 
@@ -259,6 +263,49 @@ func (a *App) writeConfig(doc *Document) error {
 	return nil
 }
 
+func (a *App) ensureShareDirectories(doc *Document) error {
+	for _, section := range doc.ShareSections() {
+		cfg := ShareFromSection(section)
+		if strings.TrimSpace(cfg.Path) == "" {
+			continue
+		}
+
+		info, err := os.Stat(cfg.Path)
+		if err == nil {
+			if info.IsDir() {
+				continue
+			}
+			return fmt.Errorf("share %q path exists but is not a directory: %s", cfg.Name, cfg.Path)
+		}
+
+		if !os.IsNotExist(err) {
+			return fmt.Errorf("check share %q path %s: %w", cfg.Name, cfg.Path, err)
+		}
+
+		a.println("")
+		a.printf("The folder for share %q does not exist yet.\n", cfg.Name)
+		a.printf("Missing folder: %s\n", cfg.Path)
+		a.println("I can create it now so the share is ready to use.")
+		a.flush()
+
+		create, promptErr := a.confirm("Create this folder now", true)
+		if promptErr != nil {
+			return promptErr
+		}
+		if !create {
+			return fmt.Errorf("share %q needs an existing folder before saving", cfg.Name)
+		}
+
+		if err := a.createDirectory(cfg.Path); err != nil {
+			return fmt.Errorf("create folder for share %q: %w", cfg.Name, err)
+		}
+
+		a.printf("Created folder %s\n", cfg.Path)
+	}
+
+	return nil
+}
+
 func (a *App) selectShare(doc *Document) (*Section, error) {
 	shares := doc.ShareSections()
 	if len(shares) == 0 {
@@ -608,6 +655,44 @@ func (a *App) writeTempConfig(serialized string) (string, error) {
 	return file.Name(), nil
 }
 
+func (a *App) createDirectory(path string) error {
+	if err := os.MkdirAll(path, 0o755); err == nil {
+		return nil
+	} else if shouldOfferPrivilegeRetry(err) {
+		a.println("")
+		a.println("Creating that folder needs administrator permission.")
+		a.println("I can try again using sudo so you can enter your admin password.")
+		a.flush()
+
+		canUseSudo := false
+		if a.lookPath != nil {
+			_, sudoErr := a.lookPath("sudo")
+			canUseSudo = sudoErr == nil
+		}
+		if !canUseSudo {
+			return fmt.Errorf("create folder %s: %w", path, err)
+		}
+
+		retry, promptErr := a.confirm("Retry folder creation with sudo", true)
+		if promptErr != nil {
+			return promptErr
+		}
+		if !retry {
+			return fmt.Errorf("create folder %s: %w", path, err)
+		}
+
+		if sudoErr := a.runner.Run("sudo", "mkdir", "-p", path); sudoErr != nil {
+			return fmt.Errorf("create folder %s with sudo: %w", path, sudoErr)
+		}
+		if sudoErr := a.runner.Run("sudo", "chmod", "755", path); sudoErr != nil {
+			return fmt.Errorf("set permissions on folder %s with sudo: %w", path, sudoErr)
+		}
+		return nil
+	} else {
+		return fmt.Errorf("create folder %s: %w", path, err)
+	}
+}
+
 func friendlyWriteError(action, path string, err error) error {
 	if errors.Is(err, os.ErrPermission) || strings.Contains(strings.ToLower(err.Error()), "permission denied") {
 		return fmt.Errorf("%s %s: administrator permission is needed", action, path)