feat(ui): use t to toggle tree on/off

internal/ui/model.go

@@ -59,6 +59,7 @@ type Model struct {
 	focus      Focus
 	showHelp   bool
 	flatMode   bool
+	treeHidden bool
 
 	width, height int
 }
@@ -202,6 +203,9 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 		switch msg.String() {
 		case "tab":
+			if m.treeHidden {
+				return m, nil
+			}
 			if m.focus == FocusTree {
 				if item, ok := m.fileList.SelectedItem().(tree.TreeItem); ok && item.IsDir {
 					return m, nil
@@ -224,8 +228,10 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.inputBuffer = ""
 
 		case "h", "[", "ctrl+h", "left":
+			if !m.treeHidden {
 				m.focus = FocusTree
 				m.updateTreeFocus()
+			}
 			m.inputBuffer = ""
 
 		case "enter":
@@ -293,6 +299,18 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.inputBuffer = ""
 			return m, nil
 
+		case "t":
+			m.treeHidden = !m.treeHidden
+			if m.treeHidden {
+				m.focus = FocusDiff
+			} else {
+				m.focus = FocusTree
+			}
+			m.updateTreeFocus()
+			m.updateSizes()
+			m.inputBuffer = ""
+			return m, nil
+
 		case "z":
 			if m.focus == FocusDiff {
 				m.pendingZ = true
@@ -478,20 +496,25 @@ func (m *Model) updateSizes() {
 		contentHeight = 1
 	}
 
-	treeWidth := int(float64(m.width) * 0.20)
-	if treeWidth < 20 {
-		treeWidth = 20
-	}
-
 	// Subtract border height (2) from contentHeight
 	listHeight := contentHeight - 2
 	if listHeight < 1 {
 		listHeight = 1
 	}
-	m.fileList.SetSize(treeWidth, listHeight)
 
+	if m.treeHidden {
+		m.fileList.SetSize(0, listHeight)
+		m.diffViewport.Width = m.width - 2 // border (2)
+		m.diffViewport.Height = listHeight
+	} else {
+		treeWidth := int(float64(m.width) * 0.20)
+		if treeWidth < 20 {
+			treeWidth = 20
+		}
+		m.fileList.SetSize(treeWidth, listHeight)
 		m.diffViewport.Width = m.width - treeWidth - 4 // border (2) + padding (2) from tree pane
 		m.diffViewport.Height = listHeight
+	}
 }
 
 func (m *Model) updateTreeFocus() {
@@ -645,8 +668,12 @@ func (m Model) View() string {
 			rightPaneView = lipgloss.JoinVertical(lipgloss.Top, header, diffView)
 		}
 
+		if m.treeHidden {
+			mainContent = rightPaneView
+		} else {
 			mainContent = lipgloss.JoinHorizontal(lipgloss.Top, treeView, rightPaneView)
 		}
+	}
 
 	var bottomBar string
 	if m.showHelp {
@@ -696,7 +723,7 @@ func (m Model) renderTopBar() string {
 }
 
 func (m Model) viewStatusBar() string {
-	shortcuts := StatusKeyStyle.Render("? Help  q Quit  Tab Switch  f Flat")
+	shortcuts := StatusKeyStyle.Render("? Help  q Quit  Tab Switch  f Flat  t Tree")
 	return StatusBarStyle.Width(m.width).Render(shortcuts)
 }
 
@@ -717,6 +744,7 @@ func (m Model) renderHelpDrawer() string {
 		HelpTextStyle.Render("H/M/L Move Cursor"),
 		HelpTextStyle.Render("e     Edit File"),
 		HelpTextStyle.Render("f     Flat Tree"),
+		HelpTextStyle.Render("t     Toggle Tree"),
 	)
 
 	return HelpDrawerStyle.Copy().