switch mentions from _inbox tags to mentions relation

README.md

@@ -170,7 +170,6 @@ ax create "Task" --type issue --status open --prio high
 | `_status` | `open`, `done` | No |
 | `_prio` | `high`, `medium`, `low` | No |
 | `_namespace` | any string | Yes (default: current user) |
-| `_inbox` | username | No (auto-set from @mentions) |
 
 ## Mentions and Inbox
 

cmd/inbox.go

@@ -17,7 +17,16 @@ var inboxCmd = &cobra.Command{
 			fmt.Fprintln(os.Stderr, err)
 			return
 		}
-		if nodes, err := d.ListNodes(db.ListFilter{TagPrefixes: []string{"_inbox::" + db.GetCurrentUser()}}); err == nil {
+		userID, err := d.GetUserByUsername(db.GetCurrentUser())
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+			return
+		}
+		if userID == "" {
+			output.PrintNodes(cmd.OutOrStdout(), nil, jsonFlag)
+			return
+		}
+		if nodes, err := d.ListNodes(db.ListFilter{MentionsUser: userID}); err == nil {
 			output.PrintNodes(cmd.OutOrStdout(), nodes, jsonFlag)
 		}
 	},

db/node.go

@@ -67,6 +67,18 @@ func (db *DB) resolveUserRef(tx *sql.Tx, ref string) (string, error) {
 	return db.ensureUser(tx, ref)
 }
 
+func (db *DB) GetUserByUsername(username string) (string, error) {
+	var id string
+	err := db.QueryRow(`
+		SELECT n.id FROM nodes n
+		JOIN tags t ON n.id = t.node_id
+		WHERE n.title = ? AND t.tag = '_type::user'`, username).Scan(&id)
+	if err == sql.ErrNoRows {
+		return "", nil
+	}
+	return id, err
+}
+
 func (db *DB) ensureNamespace(tx *sql.Tx, name string) (string, error) {
 	var existingID string
 	err := tx.QueryRow(`
@@ -125,6 +137,7 @@ type UpdateParams struct {
 type ListFilter struct {
 	TagPrefixes  []string
 	Assignee     string
+	MentionsUser string
 }
 
 func (db *DB) CreateNode(p CreateParams) (*models.Node, error) {
@@ -142,17 +155,17 @@ func (db *DB) CreateNode(p CreateParams) (*models.Node, error) {
 	}
 
 	for _, m := range parse.Mentions(p.Title + " " + p.Content) {
-		if _, err := db.ensureUser(tx, m); err != nil {
+		userID, err := db.resolveUserRef(tx, m)
+		if err != nil {
+			return nil, err
+		}
+		if _, err := tx.Exec("INSERT INTO rels (from_id, to_id, rel_type) VALUES (?, ?, ?)", id, userID, models.RelMentions); err != nil {
 			return nil, err
 		}
 	}
 
-	for _, t := range append(p.Tags, parse.Mentions(p.Title+" "+p.Content)...) {
+	for _, t := range p.Tags {
-		if !strings.HasPrefix(t, "_") && strings.HasPrefix(t, "@") {
+		if _, err := tx.Exec("INSERT INTO tags (node_id, tag) VALUES (?, ?)", id, t); err != nil {
-			if _, err = tx.Exec("INSERT INTO tags (node_id, tag) VALUES (?, ?)", id, "_inbox::"+t[1:]); err != nil {
-				return nil, err
-			}
-		} else if _, err := tx.Exec("INSERT INTO tags (node_id, tag) VALUES (?, ?)", id, t); err != nil {
 			return nil, err
 		}
 	}
@@ -188,24 +201,28 @@ func (db *DB) UpdateNode(id string, p UpdateParams) error {
 	}
 	defer tx.Rollback()
 
+	var currentTitle, currentContent string
+	err = tx.QueryRow("SELECT title, COALESCE(content, '') FROM nodes WHERE id = ?", id).Scan(&currentTitle, &currentContent)
+	if err != nil {
+		return err
+	}
+
 	upd := func(col, val string) error {
 		_, err := tx.Exec("UPDATE nodes SET "+col+" = ? WHERE id = ?", val, id)
 		return err
 	}
+	newTitle, newContent := currentTitle, currentContent
 	if p.Title != nil {
 		if err := upd("title", *p.Title); err != nil {
 			return err
 		}
+		newTitle = *p.Title
 	}
 	if p.Content != nil {
 		if err := upd("content", *p.Content); err != nil {
 			return err
 		}
-		for _, m := range parse.Mentions(*p.Content) {
+		newContent = *p.Content
-			if _, err := db.ensureUser(tx, m); err != nil {
-				return err
-			}
-		}
 	}
 	if p.DueDate != nil {
 		if err := upd("due_date", *p.DueDate); err != nil {
@@ -218,6 +235,46 @@ func (db *DB) UpdateNode(id string, p UpdateParams) error {
 		}
 	}
 
+	if p.Title != nil || p.Content != nil {
+		newMentions := parse.Mentions(newTitle + " " + newContent)
+		rows, err := tx.Query("SELECT to_id FROM rels WHERE from_id = ? AND rel_type = ?", id, models.RelMentions)
+		if err != nil {
+			return err
+		}
+		existingMentionIDs := make(map[string]bool)
+		for rows.Next() {
+			var uid string
+			if err := rows.Scan(&uid); err != nil {
+				rows.Close()
+				return err
+			}
+			existingMentionIDs[uid] = true
+		}
+		rows.Close()
+
+		mentionedUserIDs := make(map[string]bool)
+		for _, m := range newMentions {
+			userID, err := db.resolveUserRef(tx, m)
+			if err != nil {
+				return err
+			}
+			mentionedUserIDs[userID] = true
+			if !existingMentionIDs[userID] {
+				if _, err := tx.Exec("INSERT INTO rels (from_id, to_id, rel_type) VALUES (?, ?, ?)", id, userID, models.RelMentions); err != nil {
+					return err
+				}
+			}
+		}
+
+		for uid := range existingMentionIDs {
+			if !mentionedUserIDs[uid] {
+				if _, err := tx.Exec("DELETE FROM rels WHERE from_id = ? AND to_id = ? AND rel_type = ?", id, uid, models.RelMentions); err != nil {
+					return err
+				}
+			}
+		}
+	}
+
 	for _, t := range p.RemoveTags {
 		tx.Exec("DELETE FROM tags WHERE node_id = ? AND tag = ?", id, t)
 	}
@@ -315,6 +372,11 @@ func (db *DB) ListNodes(f ListFilter) ([]*models.Node, error) {
 		conds = append(conds, "r_assign.to_id = ? AND r_assign.rel_type = ?")
 		args = append(args, f.Assignee, models.RelAssignee)
 	}
+	if f.MentionsUser != "" {
+		joins = append(joins, "JOIN rels r_mentions ON n.id = r_mentions.from_id")
+		conds = append(conds, "r_mentions.to_id = ? AND r_mentions.rel_type = ?")
+		args = append(args, f.MentionsUser, models.RelMentions)
+	}
 
 	if len(joins) > 0 {
 		q += " " + strings.Join(joins, " ") + " "

models/node.go

@@ -22,6 +22,7 @@ const (
 	RelCreated     RelType = "created"
 	RelAssignee    RelType = "assignee"
 	RelInNamespace RelType = "in_namespace"
+	RelMentions    RelType = "mentions"
 )
 
 func (n *Node) GetProperty(k string) string {