feat: add toggleable raw diff view with color support

go.mod

@@ -10,6 +10,7 @@ require (
 	charm.land/lipgloss/v2 v2.0.3
 	github.com/adrg/xdg v0.5.3
 	github.com/atotto/clipboard v0.1.4
+	github.com/creack/pty v1.1.24
 	github.com/earthboundkid/versioninfo/v2 v2.24.1
 	github.com/go-playground/validator/v10 v10.30.3
 	github.com/joho/godotenv v1.5.1

internal/git/client.go

@@ -1,12 +1,15 @@
 package git
 
 import (
+	"bytes"
 	"fmt"
+	"io"
 	"os"
 	"os/exec"
 	"strings"
 
 	"github.com/cockroachdb/errors"
+	"github.com/creack/pty"
 )
 
 type Client struct {
@@ -59,38 +62,71 @@ func (c *Client) ModifiedFiles() ([]string, error) {
 	return strings.Split(trimmed, "\n"), nil
 }
 
-func (c *Client) Diff() (string, error) {
+func (c *Client) Diff(color, exclude bool) (string, error) {
+	args := c.diffArgs(color, exclude)
+
+	cmd := exec.Command("git", args...)
+	if !color {
+		result, err := cmd.CombinedOutput()
+		if err != nil {
+			return "", errors.Wrap(err, "git diff failed")
+		}
+		return strings.ReplaceAll(string(result), "\t", "    "), nil
+	}
+
+	ptmx, err := pty.Start(cmd)
+	if err != nil {
+		// fallback to plain pipe if pty fails
+		return c.Diff(false, exclude)
+	}
+	defer func() { _ = ptmx.Close() }()
+
+	var buf bytes.Buffer
+	if _, err := io.Copy(&buf, ptmx); err != nil {
+		return "", errors.Wrap(err, "reading git diff output failed")
+	}
+
+	if err := cmd.Wait(); err != nil {
+		return "", errors.Wrap(err, "waiting for git diff command failed")
+	}
+
+	return strings.ReplaceAll(buf.String(), "\t", "    "), nil
+}
+
+func (c *Client) diffArgs(color, exclude bool) []string {
 	args := []string{
 		"--no-pager",
 		"diff",
+	}
+	if color {
+		args = append(args, "--color=always")
+	}
+	args = append(args,
 		"--no-ext-diff",
 		"--no-textconv",
-	}
+	)
 
 	if c.addAll {
 		args = append(args, "HEAD")
 	} else {
 		args = append(args, "--staged")
 	}
 
-	args = append(args,
-		"--diff-filter=ACMRTUXBD",
-		"--",                 // separates options from pathspecs
-		".",                  // include everything under the repo root
-		":(exclude)*-lock.*", // package-lock.json, pnpm-lock.yaml, etc.
-		":(exclude)*.lock",   // yarn.lock, poetry.lock, Cargo.lock, etc.
-		":(exclude)**/build/**",
-		":(exclude)**/dist/**",
-		":(exclude)**/target/**",
-		":(exclude)**/out/**",
-		":(exclude)go.sum",
-	)
-
-	result, err := exec.Command("git", args...).CombinedOutput()
-	if err != nil {
-		return "", errors.Wrap(err, "git diff failed")
+	if exclude {
+		args = append(args,
+			"--diff-filter=ACMRTUXBD",
+			"--",                 // separates options from pathspecs
+			".",                  // include everything under the repo root
+			":(exclude)*-lock.*", // package-lock.json, pnpm-lock.yaml, etc.
+			":(exclude)*.lock",   // yarn.lock, poetry.lock, Cargo.lock, etc.
+			":(exclude)**/build/**",
+			":(exclude)**/dist/**",
+			":(exclude)**/target/**",
+			":(exclude)**/out/**",
+			":(exclude)go.sum",
+		)
 	}
-	return string(result), nil
+	return args
 }
 
 func (c *Client) prepareCommitMessage(message string, skipCI bool) string {

internal/interfaces/git.go

@@ -7,6 +7,6 @@ var ErrAborted = errors.New("aborted")
 type GitClient interface {
 	IsInWorkTree() error
 	ModifiedFiles() ([]string, error)
-	Diff() (string, error)
+	Diff(color, exclude bool) (string, error)
 	Commit(message string, skipCI bool) error
 }

internal/ui/commit_view.go

@@ -61,8 +61,6 @@ func initialCommitViewModel(message string, duration time.Duration) (*commitView
 	textStyles.Focused.CursorLine = lipgloss.NewStyle()
 	ta.SetStyles(textStyles)
 
-	vp := viewport.New(viewport.WithWidth(ta.Width()), viewport.WithHeight(ta.Height()))
-
 	customStyle := styles.DarkStyleConfig
 	customStyle.Document.Margin = uintPtr(0)
 	customStyle.H2.BlockSuffix = ""
@@ -76,7 +74,7 @@ func initialCommitViewModel(message string, duration time.Duration) (*commitView
 
 	return &commitViewModel{
 		textarea: ta,
-		viewport: vp,
+		viewport: viewport.New(viewport.WithWidth(ta.Width()), viewport.WithHeight(ta.Height())),
 		history:  NewHistory(message),
 		boxStyle: lipgloss.NewStyle().
 			BorderForeground(lipgloss.Color("6")). // Cyan
@@ -114,6 +112,9 @@ func (m *commitViewModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.textarea.Blur()
 			return m, func() tea.Msg { return regenerateMsg{} }
 
+		case "ctrl+d":
+			return m, func() tea.Msg { return showDiffViewMsg{} }
+
 		case "esc":
 			if m.preview {
 				m.preview = false
@@ -139,7 +140,6 @@ func (m *commitViewModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			}
 			m.preview = !m.preview
 			return m, nil
-
 		}
 
 		if m.preview {
@@ -264,21 +264,21 @@ func (m *commitViewModel) helpTextView() string {
 	}
 
 	if m.preview {
-		return fmt.Sprintf("%s:commit %s:clear %s:undo %s:regen %s:editor  %s:back",
+		return fmt.Sprintf("%s:commit %s:clear %s:regen %s:editor  %s:diff %s:back",
 			BoldYellow.Render("CTRL+A"),
 			Strikethrough.Render("CTRL+K"),
-			Strikethrough.Render("CTRL+Z"),
 			BoldYellow.Render("CTRL+R"),
 			BoldYellow.Render("CTRL+P"),
+			BoldYellow.Render("CTRL+D"),
 			BoldYellow.Render("ESC"))
 	}
 
-	return fmt.Sprintf("%s:commit %s:clear %s:undo %s:regen %s:preview %s:abort",
+	return fmt.Sprintf("%s:commit %s:clear %s:regen %s:preview %s:diff %s:abort",
 		BoldYellow.Render("CTRL+A"),
 		BoldYellow.Render("CTRL+K"),
-		BoldYellow.Render("CTRL+Z"),
 		BoldYellow.Render("CTRL+R"),
 		BoldYellow.Render("CTRL+P"),
+		BoldYellow.Render("CTRL+D"),
 		BoldYellow.Render("ESC"))
 }
 

internal/ui/diff_view.go

@@ -0,0 +1,68 @@
+package ui
+
+import (
+	"fmt"
+	"strings"
+
+	"charm.land/bubbles/v2/viewport"
+	tea "charm.land/bubbletea/v2"
+	"charm.land/lipgloss/v2"
+)
+
+type diffViewModel struct {
+	viewport viewport.Model
+	boxStyle lipgloss.Style
+}
+
+func initialDiffViewModel(width, height int) *diffViewModel {
+	vp := viewport.New(viewport.WithWidth(width), viewport.WithHeight(height))
+	vp.SoftWrap = false
+
+	return &diffViewModel{
+		viewport: vp,
+		boxStyle: lipgloss.NewStyle().
+			BorderForeground(lipgloss.Color("6")). // Cyan
+			Padding(0, 1),
+	}
+}
+
+func (m *diffViewModel) Init() tea.Cmd {
+	return nil
+}
+
+func (m *diffViewModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case tea.KeyPressMsg:
+		switch msg.String() {
+		case "esc", "ctrl+d":
+			return m, func() tea.Msg { return cancelDiffViewMsg{} }
+		}
+	case diffColorMsg:
+		m.viewport.SetContent(string(msg))
+		return m, nil
+	}
+
+	var cmd tea.Cmd
+	m.viewport, cmd = m.viewport.Update(msg)
+	return m, cmd
+}
+
+func (m *diffViewModel) View() tea.View {
+	title := " Raw diff "
+	titleBorder := lipgloss.RoundedBorder()
+
+	repeatCount := max((m.viewport.Width()+2)-lipgloss.Width(title), 0)
+	titleBorder.Top = title + strings.Repeat("─", repeatCount)
+
+	helpText := fmt.Sprintf("%s:commit %s:clear %s:regen %s:editor  %s:diff %s:back",
+		Strikethrough.Render("CTRL+A"),
+		Strikethrough.Render("CTRL+K"),
+		Strikethrough.Render("CTRL+R"),
+		Strikethrough.Render("CTRL+P"),
+		BoldYellow.Render("CTRL+D"),
+		BoldYellow.Render("ESC"))
+
+	return tea.NewView(m.boxStyle.
+		BorderStyle(titleBorder).
+		Render(m.viewport.View()) + "\n" + helpText)
+}

internal/ui/model.go

@@ -22,6 +22,7 @@ const (
 	showSpinner sessionState = iota
 	showCommitView
 	showRegeneratePrompt
+	showDiffView
 )
 
 type (
@@ -32,10 +33,13 @@ type (
 		duration time.Duration
 	}
 	commitMsg            string
+	diffColorMsg         string
 	errMsg               struct{ err error }
 	abortMsg             struct{}
 	regenerateMsg        struct{}
 	cancelRegenPromptMsg struct{}
+	showDiffViewMsg      struct{}
+	cancelDiffViewMsg    struct{}
 	userResponseMsg      string
 )
 
@@ -60,6 +64,8 @@ type Model struct {
 	spinnerMessage string
 	latestVersion  string
 	commitView     tea.Model
+	diffView       tea.Model
+	diffLoaded     bool
 	commitMessage  string
 	promptView     tea.Model
 	action         Action
@@ -86,6 +92,7 @@ func InitialModel(
 		hint:           hint,
 		spinner:        spinner.New(spinner.WithSpinner(spinner.MiniDot)),
 		spinnerMessage: Magenta.Render("Checking whether a newer version exists..."),
+		diffView:       initialDiffViewModel(72+2, 20),
 		action:         None,
 		yolo:           yolo,
 	}
@@ -96,21 +103,21 @@ func (m *Model) Init() tea.Cmd {
 }
 
 func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	var cmd tea.Cmd
+
 	switch msg := msg.(type) {
 	case tea.KeyPressMsg:
-		if msg.String() == "ctrl+c" {
-			if m.state == showSpinner {
-				m.action = Abort
-				return m, tea.Quit
-			}
+		if msg.String() == "ctrl+c" && m.state == showSpinner {
+			m.action = Abort
+			return m, tea.Quit
 		}
 
 	case gitCheckMsg:
 		if len(msg) == 0 {
 			m.err = errors.New("no changes detected")
 			return m, tea.Quit
 		}
-		return m, m.getGitDiff
+		return m, m.getGitDiffForLLM
 
 	case gitDiffMsg:
 		m.spinnerMessage = fmt.Sprintf("%s%s%s",
@@ -179,10 +186,22 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		m.hint = string(msg)
 		return m, tea.Batch(m.spinner.Tick, m.generateSummary(m.diff))
 
-	case cancelRegenPromptMsg:
+	case cancelRegenPromptMsg, cancelDiffViewMsg:
 		m.state = showCommitView
 		return m, m.commitView.Init()
 
+	case showDiffViewMsg:
+		m.state = showDiffView
+		if !m.diffLoaded {
+			return m, m.getFullDiffWithColor
+		}
+		return m, m.diffView.Init()
+
+	case diffColorMsg:
+		m.diffLoaded = true
+		m.diffView, cmd = m.diffView.Update(msg)
+		return m, cmd
+
 	case errMsg:
 		m.err = msg.err
 		return m, tea.Quit
@@ -197,14 +216,15 @@ func (m *Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		return m, m.checkGitStatus
 	}
 
-	var cmd tea.Cmd
 	switch m.state {
 	case showSpinner:
 		m.spinner, cmd = m.spinner.Update(msg)
 	case showCommitView:
 		m.commitView, cmd = m.commitView.Update(msg)
 	case showRegeneratePrompt:
 		m.promptView, cmd = m.promptView.Update(msg)
+	case showDiffView:
+		m.diffView, cmd = m.diffView.Update(msg)
 	}
 	return m, cmd
 }
@@ -221,8 +241,6 @@ func (m *Model) LatestVersion() string {
 	return m.latestVersion
 }
 
-// LatestVersionMsg is handled above to chain into git checks
-
 func (m *Model) View() tea.View {
 	switch m.state {
 	case showSpinner:
@@ -237,6 +255,8 @@ func (m *Model) View() tea.View {
 			return tea.NewView(m.spinner.View() + " " + m.spinnerMessage)
 		}
 		return tea.NewView(m.commitView.View().Content + m.promptView.View().Content)
+	case showDiffView:
+		return m.diffView.View()
 	default:
 		return tea.NewView("")
 	}
@@ -254,8 +274,16 @@ func (m *Model) checkGitStatus() tea.Msg {
 	return gitCheckMsg(modifiedFiles)
 }
 
-func (m *Model) getGitDiff() tea.Msg {
-	diff, err := m.gitClient.Diff()
+func (m *Model) getFullDiffWithColor() tea.Msg {
+	diff, err := m.gitClient.Diff(true, false)
+	if err != nil {
+		return errMsg{err}
+	}
+	return diffColorMsg(diff)
+}
+
+func (m *Model) getGitDiffForLLM() tea.Msg {
+	diff, err := m.gitClient.Diff(false, true)
 	if err != nil {
 		return errMsg{err}
 	}