Move pages to and from the vault

A page, including a journal day, can be moved into the unlocked vault with its id kept. Links to it elsewhere become [[locked:id]], shown as Locked Page until the vault is unlocked, so its title is kept only in the vault. Move out reverses it.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

internal/store/store.go

@@ -591,7 +591,7 @@ func (s *Store) relink(oldTitle, newTitle, except string) error {
 		if m.ID == except || m.Trashed || !slices.Contains(m.links, old) {
 			continue
 		}
-		body := rewriteLinks(m.Body, old, newTitle)
+		body := rewriteLinks(m.Body, old, newTitle, true)
 		if body == m.Body {
 			continue
 		}
@@ -606,7 +606,8 @@ func (s *Store) relink(oldTitle, newTitle, except string) error {
 	return nil
 }
 
-func rewriteLinks(body, old, newTitle string) string {
+// rewriteLinks points the [[old]] links in body at newTitle, keeping their |text unless keepAlias is false.
+func rewriteLinks(body, old, newTitle string, keepAlias bool) string {
 	lines := strings.Split(body, "\n")
 	fence := false
 	for i, l := range lines {
@@ -623,7 +624,7 @@ func rewriteLinks(body, old, newTitle string) string {
 				return x
 			}
 			alias := ""
-			if k := strings.Index(x, "|"); k >= 0 {
+			if k := strings.Index(x, "|"); keepAlias && k >= 0 {
 				alias = x[k : len(x)-2]
 			}
 			return "[[" + newTitle + alias + "]]"
@@ -1076,3 +1077,114 @@ func exportFormat(n *Note) []byte {
 	b.WriteString("\n")
 	return []byte(b.String())
 }
+
+// ---- moving pages between notebooks (the vault) ----
+
+// LockedPrefix starts the target of a [[link]] to a page that has been moved to the vault, so that the
+// ordinary notebook keeps the page's id and never its title.
+const LockedPrefix = "locked:"
+
+var ErrExists = errors.New("there is already a page with that id")
+
+// Import adds a page that was made in another notebook, keeping its id, dates and text. It is placed at
+// the top level, its title is changed if another page has it, and it is written before anything else
+// is touched, so a failure leaves the page where it came from.
+func (s *Store) Import(n Note) (Note, error) {
+	if !ValidID(n.ID) {
+		return Note{}, ErrBadID
+	}
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if _, ok := s.by[n.ID]; ok {
+		return Note{}, ErrExists
+	}
+	in := n.copy()
+	in.Parent, in.Trashed = "", false
+	if in.Daily != "" {
+		in.Title = in.Daily
+	} else {
+		in.Title = s.free(in.Title, in.ID)
+	}
+	in.refresh()
+	if err := s.write(&in); err != nil {
+		return Note{}, err
+	}
+	s.by[in.ID] = &in
+	return in.copy(), nil
+}
+
+// Discard removes a page with no trash and no questions. It undoes an Import that cannot be completed.
+func (s *Store) Discard(id string) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	n, ok := s.by[id]
+	if !ok {
+		return ErrNotFound
+	}
+	if err := os.Remove(s.path(n)); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return err
+	}
+	delete(s.by, id)
+	return nil
+}
+
+// Detach takes a page out of this notebook to be kept somewhere else. Pages inside it move up a level,
+// and every [[link]] to it, even in the trash, becomes [[locked:id]], so its title is left nowhere.
+func (s *Store) Detach(id string) (Note, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	n, ok := s.by[id]
+	if !ok || n.Trashed {
+		return Note{}, ErrNotFound
+	}
+	gone := n.copy()
+	for _, c := range s.by {
+		if c.Parent == id {
+			next := c.copy()
+			next.Parent = n.Parent
+			if err := s.write(&next); err != nil {
+				return Note{}, err
+			}
+			*c = next
+		}
+	}
+	if err := s.relinkAll(strings.ToLower(n.Title), LockedPrefix+id, false); err != nil {
+		return Note{}, err
+	}
+	if err := os.Remove(s.path(n)); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return Note{}, err
+	}
+	delete(s.by, id)
+	return gone, nil
+}
+
+// Reveal points the [[locked:id]] links of a page that has come back at its title again.
+func (s *Store) Reveal(id, title string) error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.relinkAll(LockedPrefix+id, title, true)
+}
+
+// relinkAll rewrites the links to old (lower-cased) in every page, trashed or not.
+func (s *Store) relinkAll(old, newTarget string, keepAlias bool) error {
+	if old == "" || newTarget == "" {
+		return nil
+	}
+	for _, m := range s.by {
+		if !slices.Contains(m.links, old) {
+			continue
+		}
+		body := rewriteLinks(m.Body, old, newTarget, keepAlias)
+		if body == m.Body {
+			continue
+		}
+		next := m.copy()
+		next.set(body)
+		next.Updated = moved(m.Updated)
+		if err := s.write(&next); err != nil {
+			return err
+		}
+		*m = next
+	}
+	return nil
+}