Config view: one list with section headings, navigated with the arrow keys

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

internal/ui/form.go

@@ -50,16 +50,19 @@ func arrowNavigation(f *tview.Form, cancel func(), hooks *browseHooks) {
 			pos = f.GetFormItemCount() + button
 		}
 		switch ev.Key() {
-		case tcell.KeyDown:
-			if pos == total-1 && hooks != nil && hooks.edge != nil && hooks.edge(true) {
+		case tcell.KeyDown, tcell.KeyUp:
+			dir := 1
+			if ev.Key() == tcell.KeyUp {
+				dir = -1
+			}
+			next := neighbour(f, pos, dir)
+			if next == pos { // nothing further in this direction
+				if hooks != nil && hooks.edge != nil && hooks.edge(dir > 0) {
+					return nil
+				}
 				return nil
 			}
-			f.SetFocus(min(pos+1, total-1))
-		case tcell.KeyUp:
-			if pos == 0 && hooks != nil && hooks.edge != nil && hooks.edge(false) {
-				return nil
-			}
-			f.SetFocus(max(pos-1, 0))
+			f.SetFocus(next)
 		case tcell.KeyTab, tcell.KeyBacktab:
 			dir := 1
 			if ev.Key() == tcell.KeyBacktab {
@@ -180,3 +183,82 @@ func (b *browser) track(dd *tview.DropDown, ev *tcell.EventKey, h *browseHooks)
 		b.known = false // paging, typed prefixes
 	}
 }
+
+// skipsFocus marks form items that only decorate (section headings): the
+// arrow keys pass over them.
+type skipsFocus interface{ skipFocus() bool }
+
+// neighbour returns the position of the next focusable item or button after
+// pos in the given direction, or pos itself if there is none.
+func neighbour(f *tview.Form, pos, dir int) int {
+	total := f.GetFormItemCount() + f.GetButtonCount()
+	for i := pos + dir; i >= 0 && i < total; i += dir {
+		if i < f.GetFormItemCount() {
+			if s, ok := f.GetFormItem(i).(skipsFocus); ok && s.skipFocus() {
+				continue
+			}
+		}
+		return i
+	}
+	return pos
+}
+
+// firstFocusable returns the position of the first item or button that can
+// take the focus.
+func firstFocusable(f *tview.Form) int {
+	if f.GetFormItemCount() == 0 {
+		return 0 // a form of buttons only
+	}
+	if s, ok := f.GetFormItem(0).(skipsFocus); ok && s.skipFocus() {
+		return neighbour(f, 0, 1)
+	}
+	return 0
+}
+
+// formHeading is a section heading inside a form: a bold title above the next
+// group of fields. It never takes the focus.
+type formHeading struct {
+	*tview.Box
+	title    string
+	finished func(tcell.Key)
+}
+
+func newFormHeading(title string) *formHeading {
+	return &formHeading{Box: tview.NewBox(), title: title}
+}
+
+func (h *formHeading) skipFocus() bool { return true }
+
+func (h *formHeading) GetLabel() string { return "" }
+
+func (h *formHeading) SetFormAttributes(int, tcell.Color, tcell.Color, tcell.Color, tcell.Color) tview.FormItem {
+	return h
+}
+
+func (h *formHeading) GetFieldWidth() int { return 0 }
+
+// GetFieldHeight is 2: an empty line above the title separates the sections.
+func (h *formHeading) GetFieldHeight() int { return 2 }
+
+func (h *formHeading) SetFinishedFunc(handler func(key tcell.Key)) tview.FormItem {
+	h.finished = handler
+	return h
+}
+
+func (h *formHeading) SetDisabled(bool) tview.FormItem { return h }
+
+// Focus passes the focus on, like a disabled input field does, so tview's own
+// Tab handling skips the heading too.
+func (h *formHeading) Focus(delegate func(p tview.Primitive)) {
+	if h.finished != nil {
+		h.finished(-1)
+		return
+	}
+	h.Box.Focus(delegate)
+}
+
+func (h *formHeading) Draw(screen tcell.Screen) {
+	h.Box.DrawForSubclass(screen, h)
+	x, y, w, _ := h.GetInnerRect()
+	tview.Print(screen, "[::b]"+tview.Escape(h.title)+"[::-]", x, y+1, w, tview.AlignLeft, tcell.ColorYellow)
+}