Add default conversation title

internal/db/queries.go

@@ -288,7 +288,7 @@ func (q *Queries) SelectConversationsUserId(ctx context.Context, userId string)
 
 const updateConversationTitle = `
 UPDATE conversations
-SET title = ?
+SET title = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')
 WHERE id = ?
 RETURNING created_at, id, title, updated_at, user_id
 `
@@ -300,15 +300,9 @@ type UpdateConversationTitleParams struct {
 	Title string
 }
 
-// UpdateConversationTitle sets the title of one conversation and
-// returns the updated row.
-//
-// The update keeps updated_at. That timestamp is the
-// conversation's synchronization token for its message set, and a
-// title is not a message: a rename must not move the conversation
-// in the picker's ordering, which sorts by updated_at.
-//
-// A conversation that is missing returns sql.ErrNoRows.
+// UpdateConversationTitle sets the title for a conversation, bumps
+// updated_at, and returns the updated row. It returns sql.ErrNoRows
+// if no conversation has that id.
 func (q *Queries) UpdateConversationTitle(
 	ctx context.Context,
 	arg UpdateConversationTitleParams,
@@ -344,6 +338,61 @@ func (q *Queries) UpdateConversationTitle(
 	return &c, nil
 }
 
+const updateConversationTitleIfUnset = `
+UPDATE conversations
+SET title = ?, updated_at = strftime('%Y-%m-%dT%H:%M:%fZ', 'now')
+WHERE id = ? AND title IS NULL
+RETURNING created_at, id, title, updated_at, user_id
+`
+
+// UpdateConversationTitleIfUnsetParams holds arguments for
+// UpdateConversationTitleIfUnset.
+type UpdateConversationTitleIfUnsetParams struct {
+	Id    string
+	Title string
+}
+
+// UpdateConversationTitleIfUnset sets the first title for a
+// conversation when title is NULL, bumps updated_at, and returns
+// the updated row. It prevents a caller from overwriting a title
+// set by a user or a scheduled job. It returns sql.ErrNoRows if
+// the conversation does not exist or already has a title; callers
+// treat both cases as no-op.
+func (q *Queries) UpdateConversationTitleIfUnset(
+	ctx context.Context,
+	arg UpdateConversationTitleIfUnsetParams,
+) (*Conversation, error) {
+	row := q.db.QueryRowContext(
+		ctx,
+		updateConversationTitleIfUnset,
+		arg.Title,
+		arg.Id,
+	)
+
+	var (
+		c         Conversation
+		createdAt string
+		updatedAt string
+		err       error
+	)
+	if err := row.Scan(
+		&createdAt,
+		&c.Id,
+		&c.Title,
+		&updatedAt,
+		&c.UserId,
+	); err != nil {
+		return nil, fmt.Errorf("UpdateConversationTitleIfUnset: %w", err)
+	}
+	if c.CreatedAt, err = time.Parse(time.RFC3339, createdAt); err != nil {
+		return nil, fmt.Errorf("UpdateConversationTitleIfUnset: parse created_at: %w", err)
+	}
+	if c.UpdatedAt, err = time.Parse(time.RFC3339, updatedAt); err != nil {
+		return nil, fmt.Errorf("UpdateConversationTitleIfUnset: parse updated_at: %w", err)
+	}
+	return &c, nil
+}
+
 const deleteConversationId = `
 DELETE FROM conversations
 WHERE id = ?