Add interactive Markdown checklist toggles in the ticket preview.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/ui/views/markdown.go

@@ -1,11 +1,15 @@
 package views
 
 import (
+	"strings"
 	"sync"
 
 	"github.com/charmbracelet/glamour"
 	"github.com/charmbracelet/glamour/styles"
+	"github.com/charmbracelet/lipgloss"
 	"github.com/muesli/termenv"
+
+	"task/internal/ticket"
 )
 
 type mdCacheKey struct {
@@ -79,6 +83,78 @@ func getRenderer(width int) (*glamour.TermRenderer, error) {
 	return r, nil
 }
 
+// RenderDescription renders ticket Markdown with interactive task-list items.
+// checklistCursor is the 0-based index among checkboxes (highlight); ignored when
+// there are none.
+func RenderDescription(src string, width int, checklistCursor int) string {
+	if strings.TrimSpace(src) == "" {
+		return ""
+	}
+	boxes := ticket.ListCheckboxes(src)
+	if len(boxes) == 0 {
+		return RenderMarkdown(src, width)
+	}
+
+	boxByLine := make(map[int]int, len(boxes))
+	for i, b := range boxes {
+		boxByLine[b.Line] = i
+	}
+
+	lines := strings.Split(src, "\n")
+	var parts []string
+	var mdBuf []string
+	flushMD := func() {
+		if len(mdBuf) == 0 {
+			return
+		}
+		block := strings.Join(mdBuf, "\n")
+		if strings.TrimSpace(block) != "" {
+			parts = append(parts, RenderMarkdown(block, width))
+		}
+		mdBuf = nil
+	}
+
+	for i, line := range lines {
+		if bi, ok := boxByLine[i]; ok {
+			flushMD()
+			parts = append(parts, renderCheckboxLine(boxes[bi], bi == checklistCursor, width))
+			continue
+		}
+		mdBuf = append(mdBuf, line)
+	}
+	flushMD()
+	if len(parts) == 0 {
+		return ""
+	}
+	return lipgloss.JoinVertical(lipgloss.Left, parts...)
+}
+
+func renderCheckboxLine(box ticket.Checkbox, selected bool, width int) string {
+	// ASCII markers — widely supported; bold + padding reads a notch bigger.
+	mark := "[ ]"
+	if box.Checked {
+		mark = "[x]"
+	}
+	prefix := "  "
+	if selected {
+		prefix = "> "
+	}
+	label := strings.TrimSpace(box.Text)
+	avail := max(10, width) - lipgloss.Width(prefix+mark+" ")
+	label = truncateOneLine(label, avail)
+
+	markStyle := lipgloss.NewStyle().Bold(true)
+	labelStyle := lipgloss.NewStyle()
+	if selected {
+		markStyle = markStyle.Foreground(lipgloss.Color("39"))
+		labelStyle = labelStyle.Bold(true).Foreground(lipgloss.Color("39"))
+	} else if box.Checked {
+		labelStyle = labelStyle.Faint(true)
+	}
+	line := prefix + markStyle.Render(mark) + " " + labelStyle.Render(label)
+	return lipgloss.NewStyle().Width(max(10, width)).Render(line)
+}
+
 // ClearMarkdownCache drops cached renders (e.g. after theme change).
 func ClearMarkdownCache() {
 	mdMu.Lock()

internal/ui/views/markdown_test.go

@@ -30,3 +30,14 @@ func TestRenderMarkdownFastWithoutAutoStyle(t *testing.T) {
 	}
 	t.Logf("first=%v cached=%v", elapsed, time.Since(start))
 }
+
+func TestRenderDescriptionHighlightsCheckbox(t *testing.T) {
+	src := "Intro\n\n- [ ] one\n- [x] two\n"
+	out := views.RenderDescription(src, 40, 0)
+	if !strings.Contains(out, "one") || !strings.Contains(out, "[ ]") {
+		t.Fatalf("expected unchecked item in output: %q", out)
+	}
+	if !strings.Contains(out, "two") || !strings.Contains(out, "[x]") {
+		t.Fatalf("expected checked item in output: %q", out)
+	}
+}

internal/ui/views/tickets.go

@@ -26,13 +26,14 @@ type TicketListStyles struct {
 
 // TicketList is a custom viewport list of ticket cards.
 type TicketList struct {
-	Items     []ticket.Ticket
-	Cursor    int
-	Offset    int
-	Width     int
-	Height    int
-	Styles    TicketListStyles
-	SpentByID map[string]time.Duration // optional; shown on selected card
+	Items            []ticket.Ticket
+	Cursor           int
+	Offset           int
+	Width            int
+	Height           int
+	Styles           TicketListStyles
+	SpentByID        map[string]time.Duration // optional; shown on selected card
+	ChecklistCursor  int                      // index into checkboxes of the selected ticket
 }
 
 // SetSize updates the viewport dimensions.
@@ -49,6 +50,7 @@ func (l *TicketList) SetItems(items []ticket.Ticket) {
 		l.Cursor = max(0, len(l.Items)-1)
 	}
 	l.Offset = 0
+	l.clampChecklistCursor()
 	l.ensureVisible()
 }
 
@@ -70,6 +72,7 @@ func (l *TicketList) Len() int { return len(l.Items) }
 func (l *TicketList) MoveDown() {
 	if l.Cursor < len(l.Items)-1 {
 		l.Cursor++
+		l.ChecklistCursor = 0
 		l.ensureVisible()
 	}
 }
@@ -78,6 +81,7 @@ func (l *TicketList) MoveDown() {
 func (l *TicketList) MoveUp() {
 	if l.Cursor > 0 {
 		l.Cursor--
+		l.ChecklistCursor = 0
 		l.ensureVisible()
 	}
 }
@@ -87,10 +91,61 @@ func (l *TicketList) Select(idx int) {
 	if idx < 0 || idx >= len(l.Items) {
 		return
 	}
+	if l.Cursor != idx {
+		l.ChecklistCursor = 0
+	}
 	l.Cursor = idx
+	l.clampChecklistCursor()
 	l.ensureVisible()
 }
 
+// ChecklistLen returns how many task-list items the selected ticket has.
+func (l *TicketList) ChecklistLen() int {
+	t, ok := l.Selected()
+	if !ok {
+		return 0
+	}
+	return len(ticket.ListCheckboxes(t.Description))
+}
+
+// MoveChecklistDown advances the checkbox cursor (wraps).
+func (l *TicketList) MoveChecklistDown() {
+	n := l.ChecklistLen()
+	if n == 0 {
+		return
+	}
+	l.ChecklistCursor = (l.ChecklistCursor + 1) % n
+}
+
+// MoveChecklistUp moves the checkbox cursor up (wraps).
+func (l *TicketList) MoveChecklistUp() {
+	n := l.ChecklistLen()
+	if n == 0 {
+		return
+	}
+	l.ChecklistCursor = (l.ChecklistCursor - 1 + n) % n
+}
+
+// SetChecklistCursor sets the checkbox highlight index (clamped).
+func (l *TicketList) SetChecklistCursor(idx int) {
+	l.ChecklistCursor = idx
+	l.clampChecklistCursor()
+}
+
+func (l *TicketList) clampChecklistCursor() {
+	n := l.ChecklistLen()
+	if n == 0 {
+		l.ChecklistCursor = 0
+		return
+	}
+	if l.ChecklistCursor < 0 {
+		l.ChecklistCursor = 0
+	}
+	if l.ChecklistCursor >= n {
+		l.ChecklistCursor = n - 1
+	}
+}
+
 // View renders only the visible ticket cards.
 func (l *TicketList) View() string {
 	if l.Height < 1 {
@@ -126,16 +181,15 @@ func (l *TicketList) renderCard(t ticket.Ticket, selected bool) string {
 
 	var content string
 	if selected {
-		// Expanded: headline + optional spent + glamour description.
+		// Expanded: headline + optional spent + description (interactive checkboxes).
 		content = headerLine
 		if spent, ok := l.SpentByID[t.ID]; ok && spent > 0 {
 			content += "\n" + lipgloss.NewStyle().Faint(true).Render(
 				"spent: "+ticket.FormatDurationHuman(spent),
 			)
 		}
-		desc := strings.TrimSpace(t.Description)
-		if desc != "" {
-			content += "\n" + RenderMarkdown(desc, innerWidth)
+		if strings.TrimSpace(t.Description) != "" {
+			content += "\n" + RenderDescription(t.Description, innerWidth, l.ChecklistCursor)
 		}
 	} else {
 		content = headerLine