chore: clean the project

internal/config/config.go

@@ -10,10 +10,9 @@ type UIConfig struct {
 }
 
 func Load() Config {
-	// Default configuration
 	return Config{
 		UI: UIConfig{
-			LineNumbers: "relative", // Default to relative numbers (vim style)
+			LineNumbers: "hybrid",
 			Theme:       "default",
 		},
 	}

internal/tree/builder.go

@@ -9,7 +9,7 @@ import (
 	"github.com/charmbracelet/bubbles/list"
 )
 
-// TreeItem represents a file or folder in the UI list.
+// TreeItem represents a file or folder
 type TreeItem struct {
 	Path     string
 	FullPath string
@@ -25,16 +25,12 @@ func (i TreeItem) Title() string {
 	return fmt.Sprintf("%s%s %s", indent, icon, i.Path)
 }
 
-// Build converts a list of file paths into a sorted tree list.
-// Compaction is disabled to ensure tree stability.
 func Build(paths []string) []list.Item {
-	// Initialize root
 	root := &node{
 		children: make(map[string]*node),
 		isDir:    true,
 	}
 
-	// 1. Build the raw tree structure
 	for _, path := range paths {
 		parts := strings.Split(path, "/")
 		current := root
@@ -53,14 +49,11 @@ func Build(paths []string) []list.Item {
 		}
 	}
 
-	// 2. Flatten to list items (Sorting happens here)
 	var items []list.Item
 	flatten(root, 0, &items)
 	return items
 }
 
-// -- Helpers --
-
 type node struct {
 	name     string
 	fullPath string
@@ -75,10 +68,8 @@ func flatten(n *node, depth int, items *[]list.Item) {
 		keys = append(keys, k)
 	}
 
-	// Sort: Directories first, then alphabetical
 	sort.Slice(keys, func(i, j int) bool {
 		a, b := n.children[keys[i]], n.children[keys[j]]
-		// Folders first
 		if a.isDir && !b.isDir {
 			return true
 		}
@@ -90,7 +81,6 @@ func flatten(n *node, depth int, items *[]list.Item) {
 
 	for _, k := range keys {
 		child := n.children[k]
-		// Add current node
 		*items = append(*items, TreeItem{
 			Path:     child.name,
 			FullPath: child.fullPath,
@@ -98,7 +88,6 @@ func flatten(n *node, depth int, items *[]list.Item) {
 			Depth:    depth,
 		})
 
-		// Recurse if directory
 		if child.isDir {
 			flatten(child, depth+1, items)
 		}

internal/ui/model.go

@@ -39,6 +39,7 @@ type Model struct {
 	diffCursor  int
 
 	inputBuffer string
+	pendingZ    bool
 
 	focus    Focus
 	showHelp bool
@@ -72,6 +73,7 @@ func NewModel(cfg config.Config, targetBranch string) Model {
 		repoName:      git.GetRepoName(),
 		showHelp:      false,
 		inputBuffer:   "",
+		pendingZ:      false,
 	}
 
 	if len(items) > 0 {
@@ -118,11 +120,30 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			return m, tea.Quit
 		}
 
-		// If list is empty, ignore other keys
 		if len(m.fileTree.Items()) == 0 {
 			return m, nil
 		}
 
+		// Handle z-prefix commands (zz, zt, zb)
+		if m.pendingZ {
+			m.pendingZ = false
+			if m.focus == FocusDiff {
+				switch msg.String() {
+				case "z", ".":
+					m.centerDiffCursor()
+				case "t":
+					m.diffViewport.SetYOffset(m.diffCursor)
+				case "b":
+					offset := m.diffCursor - m.diffViewport.Height + 1
+					if offset < 0 {
+						offset = 0
+					}
+					m.diffViewport.SetYOffset(offset)
+				}
+			}
+			return m, nil
+		}
+
 		if len(msg.String()) == 1 && strings.ContainsAny(msg.String(), "0123456789") {
 			m.inputBuffer += msg.String()
 			return m, nil
@@ -166,6 +187,62 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 				return m, git.OpenEditorCmd(m.selectedPath, line)
 			}
 
+		// Viewport trigger
+		case "z":
+			if m.focus == FocusDiff {
+				m.pendingZ = true
+				return m, nil
+			}
+
+		// Cursor screen positioning (H, M, L)
+		case "H":
+			if m.focus == FocusDiff {
+				m.diffCursor = m.diffViewport.YOffset
+				if m.diffCursor >= len(m.diffLines) {
+					m.diffCursor = len(m.diffLines) - 1
+				}
+			}
+
+		case "M":
+			if m.focus == FocusDiff {
+				half := m.diffViewport.Height / 2
+				m.diffCursor = m.diffViewport.YOffset + half
+				if m.diffCursor >= len(m.diffLines) {
+					m.diffCursor = len(m.diffLines) - 1
+				}
+			}
+
+		case "L":
+			if m.focus == FocusDiff {
+				m.diffCursor = m.diffViewport.YOffset + m.diffViewport.Height - 1
+				if m.diffCursor >= len(m.diffLines) {
+					m.diffCursor = len(m.diffLines) - 1
+				}
+			}
+
+		// Page navigation
+		case "ctrl+d":
+			if m.focus == FocusDiff {
+				halfScreen := m.diffViewport.Height / 2
+				m.diffCursor += halfScreen
+				if m.diffCursor >= len(m.diffLines) {
+					m.diffCursor = len(m.diffLines) - 1
+				}
+				m.centerDiffCursor()
+			}
+			m.inputBuffer = ""
+
+		case "ctrl+u":
+			if m.focus == FocusDiff {
+				halfScreen := m.diffViewport.Height / 2
+				m.diffCursor -= halfScreen
+				if m.diffCursor < 0 {
+					m.diffCursor = 0
+				}
+				m.centerDiffCursor()
+			}
+			m.inputBuffer = ""
+
 		case "j", "down":
 			keyHandled = true
 			count := m.getRepeatCount()
@@ -173,6 +250,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 				if m.focus == FocusDiff {
 					if m.diffCursor < len(m.diffLines)-1 {
 						m.diffCursor++
+						// Scroll if hitting bottom edge
 						if m.diffCursor >= m.diffViewport.YOffset+m.diffViewport.Height {
 							m.diffViewport.LineDown(1)
 						}
@@ -190,6 +268,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 				if m.focus == FocusDiff {
 					if m.diffCursor > 0 {
 						m.diffCursor--
+						// Scroll if hitting top edge
 						if m.diffCursor < m.diffViewport.YOffset {
 							m.diffViewport.LineUp(1)
 						}
@@ -234,6 +313,15 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	return m, tea.Batch(cmds...)
 }
 
+func (m *Model) centerDiffCursor() {
+	halfScreen := m.diffViewport.Height / 2
+	targetOffset := m.diffCursor - halfScreen
+	if targetOffset < 0 {
+		targetOffset = 0
+	}
+	m.diffViewport.SetYOffset(targetOffset)
+}
+
 func (m *Model) updateSizes() {
 	reservedHeight := 1
 	if m.showHelp {
@@ -265,12 +353,11 @@ func (m Model) View() string {
 		return "Loading..."
 	}
 
-	// EMPTY STATE CHECK
 	if len(m.fileTree.Items()) == 0 {
 		return m.viewEmptyState()
 	}
 
-	// 1. PANES
+	// Panes
 	treeStyle := PaneStyle
 	if m.focus == FocusTree {
 		treeStyle = FocusedPaneStyle
@@ -335,7 +422,7 @@ func (m Model) View() string {
 
 	mainPanes := lipgloss.JoinHorizontal(lipgloss.Top, treeView, diffView)
 
-	// 2. BOTTOM AREA
+	// Bottom area
 	repoSection := StatusKeyStyle.Render(" " + m.repoName)
 	divider := StatusDividerStyle.Render("│")
 
@@ -366,12 +453,12 @@ func (m Model) View() string {
 			HelpTextStyle.Render("→/l   Right Panel"),
 		)
 		col3 := lipgloss.JoinVertical(lipgloss.Left,
-			HelpTextStyle.Render("Tab   Switch Panel"),
+			HelpTextStyle.Render("C-d/u Page Dn/Up"),
-			HelpTextStyle.Render("Num   Motion Count"),
+			HelpTextStyle.Render("zz/zt Scroll View"),
 		)
 		col4 := lipgloss.JoinVertical(lipgloss.Left,
+			HelpTextStyle.Render("H/M/L Move Cursor"),
 			HelpTextStyle.Render("e     Edit File"),
-			HelpTextStyle.Render("?     Close Help"),
 		)
 
 		helpDrawer := HelpDrawerStyle.Copy().
@@ -394,17 +481,13 @@ func (m Model) View() string {
 	return finalView
 }
 
-// viewEmptyState renders a "Landing Page" when there are no changes
 func (m Model) viewEmptyState() string {
-	// 1. Logo & Tagline
 	logo := EmptyLogoStyle.Render("difi")
 	desc := EmptyDescStyle.Render("A calm, focused way to review Git diffs.")
 
-	// 2. Status Message
 	statusMsg := fmt.Sprintf("✓ No changes found against '%s'", m.targetBranch)
 	status := EmptyStatusStyle.Render(statusMsg)
 
-	// 3. Usage Guide
 	usageHeader := EmptyHeaderStyle.Render("Usage Patterns")
 
 	cmd1 := lipgloss.NewStyle().Foreground(ColorText).Render("difi")
@@ -423,7 +506,6 @@ func (m Model) viewEmptyState() string {
 		lipgloss.JoinHorizontal(lipgloss.Left, cmd3, desc3),
 	)
 
-	// 4. Navigation Guide
 	navHeader := EmptyHeaderStyle.Render("Navigation")
 
 	key1 := lipgloss.NewStyle().Foreground(ColorText).Render("Tab")
@@ -432,8 +514,8 @@ func (m Model) viewEmptyState() string {
 	key2 := lipgloss.NewStyle().Foreground(ColorText).Render("j / k")
 	keyDesc2 := EmptyCodeStyle.Render("Move cursor")
 
-	key3 := lipgloss.NewStyle().Foreground(ColorText).Render("?")
+	key3 := lipgloss.NewStyle().Foreground(ColorText).Render("zz/zt")
-	keyDesc3 := EmptyCodeStyle.Render("Toggle help")
+	keyDesc3 := EmptyCodeStyle.Render("Center/Top")
 
 	navBlock := lipgloss.JoinVertical(lipgloss.Left,
 		navHeader,
@@ -442,10 +524,9 @@ func (m Model) viewEmptyState() string {
 		lipgloss.JoinHorizontal(lipgloss.Left, key3, keyDesc3),
 	)
 
-	// Combine blocks
 	guides := lipgloss.JoinHorizontal(lipgloss.Top,
 		usageBlock,
-		lipgloss.NewStyle().Width(8).Render(""), // Spacer
+		lipgloss.NewStyle().Width(8).Render(""),
 		navBlock,
 	)
 
@@ -457,7 +538,6 @@ func (m Model) viewEmptyState() string {
 		guides,
 	)
 
-	// Center vertically
 	var verticalPad string
 	if m.height > lipgloss.Height(content) {
 		lines := (m.height - lipgloss.Height(content)) / 2

internal/ui/styles.go

@@ -6,18 +6,18 @@ import (
 )
 
 var (
-	// Global Config
+	// Config
 	CurrentConfig config.Config
 
-	// -- THEME COLORS --
+	// Theme colors
 	ColorBorder   = lipgloss.AdaptiveColor{Light: "#D9DCCF", Dark: "#383838"}
 	ColorFocus    = lipgloss.AdaptiveColor{Light: "#000000", Dark: "#E5E5E5"}
 	ColorText     = lipgloss.AdaptiveColor{Light: "#1F1F1F", Dark: "#F8F8F2"}
 	ColorSubtle   = lipgloss.AdaptiveColor{Light: "#A8A8A8", Dark: "#626262"}
 	ColorCursorBg = lipgloss.AdaptiveColor{Light: "#E5E5E5", Dark: "#3E3E3E"}
-	ColorAccent   = lipgloss.AdaptiveColor{Light: "#00ADD8", Dark: "#00ADD8"} // Go Blue
+	ColorAccent   = lipgloss.AdaptiveColor{Light: "#00ADD8", Dark: "#00ADD8"} // Go blue
 
-	// -- PANE STYLES --
+	// Pane styles
 	PaneStyle = lipgloss.NewStyle().
 			Border(lipgloss.NormalBorder(), false, true, false, false).
 			BorderForeground(ColorBorder)
@@ -28,7 +28,7 @@ var (
 	DiffStyle = lipgloss.NewStyle().Padding(0, 0)
 	ItemStyle = lipgloss.NewStyle().PaddingLeft(2)
 
-	// -- LIST DELEGATE STYLES --
+	// List styles
 	SelectedItemStyle = lipgloss.NewStyle().
 				PaddingLeft(1).
 				Background(ColorCursorBg).
@@ -42,11 +42,11 @@ var (
 				Bold(true).
 				PaddingLeft(1)
 
-	// -- ICON STYLES --
+	// Icon styles
 	FolderIconStyle = lipgloss.NewStyle().Foreground(lipgloss.AdaptiveColor{Light: "#F7B96E", Dark: "#E5C07B"})
 	FileIconStyle   = lipgloss.NewStyle().Foreground(lipgloss.AdaptiveColor{Light: "#969696", Dark: "#ABB2BF"})
 
-	// -- DIFF VIEW STYLES --
+	// Diff view styles
 	LineNumberStyle = lipgloss.NewStyle().
 			Foreground(ColorSubtle).
 			PaddingRight(1).
@@ -56,10 +56,11 @@ var (
 				Background(ColorCursorBg).
 				Width(1000)
 
-	// -- STATUS BAR STYLES --
+	// Status bar colors
 	ColorBarBg = lipgloss.AdaptiveColor{Light: "#F2F2F2", Dark: "#1F1F1F"}
 	ColorBarFg = lipgloss.AdaptiveColor{Light: "#6E6E6E", Dark: "#9E9E9E"}
 
+	// Status bar styles
 	StatusBarStyle = lipgloss.NewStyle().
 			Foreground(ColorBarFg).
 			Background(ColorBarBg).
@@ -76,7 +77,7 @@ var (
 				Background(ColorBarBg).
 				Padding(0, 0)
 
-	// -- HELP STYLES --
+	// Help styles
 	HelpTextStyle = lipgloss.NewStyle().
 			Foreground(ColorSubtle).
 			Padding(0, 1)
@@ -86,7 +87,7 @@ var (
 			BorderForeground(ColorBorder).
 			Padding(1, 2)
 
-	// -- EMPTY STATE / LANDING PAGE STYLES --
+	// Empty/landing styles
 	EmptyLogoStyle = lipgloss.NewStyle().
 			Foreground(ColorAccent).
 			Bold(true).