Add configuration

README.md

@@ -55,6 +55,39 @@ gh-threads --repo owner/repository \
   --endpoint https://github.example.com/api/graphql
 ```
 
+## Configuration
+
+The optional TOML configuration is loaded from
+`$GH_THREADS_CONFIG`, `$XDG_CONFIG_HOME/gh-threads/config.toml`, or the
+operating system's user configuration directory at `gh-threads/config.toml`.
+On Linux this is normally `~/.config/gh-threads/config.toml`. On macOS,
+`~/Library/Application Support/gh-threads/config.toml` is preferred, with
+`~/.config/gh-threads/config.toml` automatically used as a fallback when it
+exists.
+
+```toml
+theme = "dark"                 # "dark" or "light"
+refresh_interval = "10s"
+repository = ""               # optional owner/repository default
+show_all = false              # requires repository
+limit = 50
+endpoint = "https://api.github.com/graphql"
+
+[display]
+fold_resolved = true
+thread_list_width_percent = 33 # 20-60
+
+[paths]
+scroll = false
+scroll_interval = "350ms"      # minimum 50ms
+```
+
+Command-line flags override the configuration. `GH_REPO` overrides the
+configured repository when `--repo` is not provided. The corresponding flags
+include `--config`, `--theme`, `--poll`, `--fold-resolved`,
+`--thread-list-width`, `--path-scroll`, and `--path-scroll-interval`. Boolean
+settings can be disabled explicitly, for example `--path-scroll=false`.
+
 ## Keys
 
 | Key | Action |

config.go

@@ -0,0 +1,136 @@
+package main
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"github.com/BurntSushi/toml"
+)
+
+type configDuration struct {
+	time.Duration
+}
+
+func (d *configDuration) UnmarshalText(text []byte) error {
+	value, err := time.ParseDuration(string(text))
+	if err != nil {
+		return err
+	}
+	d.Duration = value
+	return nil
+}
+
+type Config struct {
+	Theme           string         `toml:"theme"`
+	RefreshInterval configDuration `toml:"refresh_interval"`
+	Repository      string         `toml:"repository"`
+	ShowAll         bool           `toml:"show_all"`
+	Limit           int            `toml:"limit"`
+	Endpoint        string         `toml:"endpoint"`
+	Display         DisplayConfig  `toml:"display"`
+	Paths           PathConfig     `toml:"paths"`
+}
+
+type DisplayConfig struct {
+	FoldResolved           bool `toml:"fold_resolved"`
+	ThreadListWidthPercent int  `toml:"thread_list_width_percent"`
+}
+
+type PathConfig struct {
+	Scroll         bool           `toml:"scroll"`
+	ScrollInterval configDuration `toml:"scroll_interval"`
+}
+
+func defaultConfig() Config {
+	return Config{
+		Theme:           "dark",
+		RefreshInterval: configDuration{10 * time.Second},
+		Limit:           50,
+		Endpoint:        "https://api.github.com/graphql",
+		Display: DisplayConfig{
+			FoldResolved:           true,
+			ThreadListWidthPercent: 33,
+		},
+		Paths: PathConfig{
+			Scroll:         false,
+			ScrollInterval: configDuration{350 * time.Millisecond},
+		},
+	}
+}
+
+func configPath() (string, error) {
+	if path := os.Getenv("GH_THREADS_CONFIG"); path != "" {
+		return path, nil
+	}
+	if base := os.Getenv("XDG_CONFIG_HOME"); base != "" {
+		return filepath.Join(base, "gh-threads", "config.toml"), nil
+	}
+	base, err := os.UserConfigDir()
+	if err != nil {
+		return "", fmt.Errorf("find user config directory: %w", err)
+	}
+	preferred := filepath.Join(base, "gh-threads", "config.toml")
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return "", fmt.Errorf("find home directory: %w", err)
+	}
+	fallback := filepath.Join(home, ".config", "gh-threads", "config.toml")
+	return existingConfigPath(preferred, fallback), nil
+}
+
+func existingConfigPath(preferred, fallback string) string {
+	if _, err := os.Stat(preferred); err == nil || !errors.Is(err, os.ErrNotExist) {
+		return preferred
+	}
+	if _, err := os.Stat(fallback); err == nil {
+		return fallback
+	}
+	return preferred
+}
+
+func loadConfig(path string, required bool) (Config, error) {
+	config := defaultConfig()
+	metadata, err := toml.DecodeFile(path, &config)
+	if err != nil {
+		if !required && errors.Is(err, os.ErrNotExist) {
+			return config, nil
+		}
+		return Config{}, fmt.Errorf("read config %s: %w", path, err)
+	}
+	if undecoded := metadata.Undecoded(); len(undecoded) > 0 {
+		keys := make([]string, len(undecoded))
+		for i, key := range undecoded {
+			keys[i] = key.String()
+		}
+		return Config{}, fmt.Errorf("config %s contains unknown settings: %s", path, strings.Join(keys, ", "))
+	}
+	return config, nil
+}
+
+func validateConfig(config Config) error {
+	switch config.Theme {
+	case "dark", "light":
+	default:
+		return fmt.Errorf("theme must be dark or light")
+	}
+	if config.RefreshInterval.Duration < 2*time.Second {
+		return fmt.Errorf("refresh_interval must be at least 2s")
+	}
+	if config.Limit < 1 || config.Limit > 100 {
+		return fmt.Errorf("limit must be between 1 and 100")
+	}
+	if config.Paths.ScrollInterval.Duration < 50*time.Millisecond {
+		return fmt.Errorf("paths.scroll_interval must be at least 50ms")
+	}
+	if config.Display.ThreadListWidthPercent < 20 || config.Display.ThreadListWidthPercent > 60 {
+		return fmt.Errorf("display.thread_list_width_percent must be between 20 and 60")
+	}
+	if config.ShowAll && config.Repository == "" {
+		return fmt.Errorf("show_all requires repository")
+	}
+	return nil
+}

config_test.go

@@ -0,0 +1,128 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestLoadConfigUsesDefaultsWhenOptionalFileIsMissing(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "missing.toml")
+	got, err := loadConfig(path, false)
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := defaultConfig()
+	if got.Theme != want.Theme ||
+		got.RefreshInterval.Duration != want.RefreshInterval.Duration ||
+		got.Paths.Scroll != want.Paths.Scroll ||
+		got.Display.FoldResolved != want.Display.FoldResolved {
+		t.Fatalf("defaults = %#v, want %#v", got, want)
+	}
+}
+
+func TestLoadConfigParsesUserSettings(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "config.toml")
+	content := `
+theme = "light"
+refresh_interval = "25s"
+repository = "owner/repo"
+show_all = true
+limit = 75
+endpoint = "https://github.example.com/api/graphql"
+
+[display]
+fold_resolved = false
+thread_list_width_percent = 45
+
+[paths]
+scroll = true
+scroll_interval = "125ms"
+`
+	if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	got, err := loadConfig(path, true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := validateConfig(got); err != nil {
+		t.Fatal(err)
+	}
+	if got.Theme != "light" || got.RefreshInterval.Duration != 25*time.Second ||
+		got.Repository != "owner/repo" || !got.ShowAll || got.Limit != 75 ||
+		got.Display.FoldResolved || got.Display.ThreadListWidthPercent != 45 ||
+		!got.Paths.Scroll || got.Paths.ScrollInterval.Duration != 125*time.Millisecond {
+		t.Fatalf("config = %#v", got)
+	}
+}
+
+func TestLoadConfigRejectsUnknownSettings(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "config.toml")
+	if err := os.WriteFile(path, []byte("refesh_interval = \"10s\"\n"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	_, err := loadConfig(path, true)
+	if err == nil || !strings.Contains(err.Error(), "refesh_interval") {
+		t.Fatalf("unknown setting error = %v", err)
+	}
+}
+
+func TestConfigPathHonorsEnvironmentOverride(t *testing.T) {
+	t.Setenv("GH_THREADS_CONFIG", "/tmp/custom-gh-threads.toml")
+	got, err := configPath()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if got != "/tmp/custom-gh-threads.toml" {
+		t.Fatalf("config path = %q", got)
+	}
+}
+
+func TestExistingConfigPathFallsBackToDotConfig(t *testing.T) {
+	root := t.TempDir()
+	preferred := filepath.Join(root, "Library", "Application Support", "gh-threads", "config.toml")
+	fallback := filepath.Join(root, ".config", "gh-threads", "config.toml")
+	if err := os.MkdirAll(filepath.Dir(fallback), 0o700); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(fallback, []byte("theme = \"dark\"\n"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	if got := existingConfigPath(preferred, fallback); got != fallback {
+		t.Fatalf("config path = %q, want fallback %q", got, fallback)
+	}
+
+	if err := os.MkdirAll(filepath.Dir(preferred), 0o700); err != nil {
+		t.Fatal(err)
+	}
+	if err := os.WriteFile(preferred, []byte("theme = \"light\"\n"), 0o600); err != nil {
+		t.Fatal(err)
+	}
+	if got := existingConfigPath(preferred, fallback); got != preferred {
+		t.Fatalf("config path = %q, want preferred %q", got, preferred)
+	}
+}
+
+func TestConfigPathHonorsXDGConfigHome(t *testing.T) {
+	t.Setenv("GH_THREADS_CONFIG", "")
+	t.Setenv("XDG_CONFIG_HOME", "/tmp/xdg-config")
+	got, err := configPath()
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := "/tmp/xdg-config/gh-threads/config.toml"
+	if got != want {
+		t.Fatalf("config path = %q, want %q", got, want)
+	}
+}
+
+func TestValidateConfigRejectsUnsafeAnimationRate(t *testing.T) {
+	config := defaultConfig()
+	config.Paths.ScrollInterval.Duration = 10 * time.Millisecond
+	if err := validateConfig(config); err == nil {
+		t.Fatal("unsafe path scrolling interval was accepted")
+	}
+}

go.mod

@@ -3,6 +3,7 @@ module git.pablu.de/Pablu/gh-threads
 go 1.24.0
 
 require (
+	github.com/BurntSushi/toml v1.5.0
 	github.com/alecthomas/chroma/v2 v2.20.0
 	github.com/charmbracelet/bubbletea v1.3.10
 	github.com/charmbracelet/glamour v1.0.0

go.sum

@@ -1,3 +1,5 @@
+github.com/BurntSushi/toml v1.5.0 h1:W5quZX/G/csjUnuI8SUYlsHs9M38FC7znL0lIO+DvMg=
+github.com/BurntSushi/toml v1.5.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=
 github.com/alecthomas/assert/v2 v2.11.0 h1:2Q9r3ki8+JYXvGsDyBXwH3LcJ+WK5D0gc5E8vS6K3D0=
 github.com/alecthomas/assert/v2 v2.11.0/go.mod h1:Bze95FyfUr7x34QZrjL+XP+0qgp/zg8yS+TtBj1WA3k=
 github.com/alecthomas/chroma/v2 v2.20.0 h1:sfIHpxPyR07/Oylvmcai3X/exDlE8+FA820NTz+9sGw=

highlight.go

@@ -13,6 +13,8 @@ import (
 
 const reviewContextLines = 3
 
+var codeHighlightTheme = "github-dark"
+
 var hunkHeaderPattern = regexp.MustCompile(`^@@ -(\d+)(?:,\d+)? \+(\d+)(?:,\d+)? @@`)
 
 type highlightedDiffLine struct {
@@ -223,7 +225,7 @@ func coordinateText(line int) string {
 
 func highlightedSource(lexer, source string) string {
 	var highlighted bytes.Buffer
-	if err := quick.Highlight(&highlighted, source, lexer, "terminal16m", "github-dark"); err != nil {
+	if err := quick.Highlight(&highlighted, source, lexer, "terminal16m", codeHighlightTheme); err != nil {
 		return source
 	}
 	return strings.TrimSuffix(highlighted.String(), "\n")

main.go

@@ -5,45 +5,99 @@ import (
 	"fmt"
 	"os"
 	"strings"
-	"time"
 
 	tea "github.com/charmbracelet/bubbletea"
 )
 
 func main() {
+	defaults := defaultConfig()
+	defaultConfigPath, err := configPath()
+	if err != nil {
+		exitf("configuration: %v", err)
+	}
 	var (
-		repo     = flag.String("repo", os.Getenv("GH_REPO"), "optional GitHub repository filter as owner/name (or GH_REPO)")
-		poll     = flag.Duration("poll", 10*time.Second, "refresh interval")
-		showAll  = flag.Bool("all", false, "show all open PRs in --repo, not only PRs assigned to you")
-		limit    = flag.Int("limit", 50, "maximum open PRs to load (1-100)")
-		endpoint = flag.String("endpoint", "https://api.github.com/graphql", "GitHub GraphQL endpoint")
+		configFile     = flag.String("config", defaultConfigPath, "TOML configuration file")
+		repo           = flag.String("repo", "", "optional GitHub repository filter as owner/name (or GH_REPO)")
+		poll           = flag.Duration("poll", defaults.RefreshInterval.Duration, "refresh interval")
+		showAll        = flag.Bool("all", defaults.ShowAll, "show all open PRs in --repo, not only PRs assigned to you")
+		limit          = flag.Int("limit", defaults.Limit, "maximum open PRs to load (1-100)")
+		endpoint       = flag.String("endpoint", defaults.Endpoint, "GitHub GraphQL endpoint")
+		theme          = flag.String("theme", defaults.Theme, "color theme: dark or light")
+		foldResolved   = flag.Bool("fold-resolved", defaults.Display.FoldResolved, "start resolved threads folded")
+		listWidth      = flag.Int("thread-list-width", defaults.Display.ThreadListWidthPercent, "thread list width as terminal percentage (20-60)")
+		pathScroll     = flag.Bool("path-scroll", defaults.Paths.Scroll, "scroll truncated paths")
+		pathScrollRate = flag.Duration("path-scroll-interval", defaults.Paths.ScrollInterval.Duration, "path scrolling interval")
 	)
 	flag.Parse()
 
+	visited := map[string]bool{}
+	flag.Visit(func(item *flag.Flag) { visited[item.Name] = true })
+	config, err := loadConfig(*configFile, visited["config"] || os.Getenv("GH_THREADS_CONFIG") != "")
+	if err != nil {
+		exitf("configuration: %v", err)
+	}
+	if visited["repo"] {
+		config.Repository = *repo
+	} else if envRepo := os.Getenv("GH_REPO"); envRepo != "" {
+		config.Repository = envRepo
+	}
+	if visited["poll"] {
+		config.RefreshInterval.Duration = *poll
+	}
+	if visited["all"] {
+		config.ShowAll = *showAll
+	}
+	if visited["limit"] {
+		config.Limit = *limit
+	}
+	if visited["endpoint"] {
+		config.Endpoint = *endpoint
+	}
+	if visited["theme"] {
+		config.Theme = *theme
+	}
+	if visited["fold-resolved"] {
+		config.Display.FoldResolved = *foldResolved
+	}
+	if visited["thread-list-width"] {
+		config.Display.ThreadListWidthPercent = *listWidth
+	}
+	if visited["path-scroll"] {
+		config.Paths.Scroll = *pathScroll
+	}
+	if visited["path-scroll-interval"] {
+		config.Paths.ScrollInterval.Duration = *pathScrollRate
+	}
+	if err := validateConfig(config); err != nil {
+		exitf("configuration: %v", err)
+	}
+
 	var owner, name string
-	if *repo != "" {
-		parts := strings.Split(*repo, "/")
+	if config.Repository != "" {
+		parts := strings.Split(config.Repository, "/")
 		if len(parts) != 2 || parts[0] == "" || parts[1] == "" {
 			exitf("--repo must be owner/name")
 		}
 		owner, name = parts[0], parts[1]
 	}
-	if *showAll && owner == "" {
-		exitf("--all requires --repo")
+	if err := applyTheme(config.Theme); err != nil {
+		exitf("configuration: %v", err)
 	}
-	if *limit < 1 || *limit > 100 {
-		exitf("--limit must be between 1 and 100")
-	}
-	if *poll < 2*time.Second {
-		exitf("--poll must be at least 2s")
-	}
-	token, err := resolveToken(*endpoint)
+	token, err := resolveToken(config.Endpoint)
 	if err != nil {
 		exitf("authenticate: %v", err)
 	}
 
-	client := NewGitHubClient(*endpoint, token)
-	app := NewApp(client, owner, name, *showAll, *limit, *poll)
+	client := NewGitHubClient(config.Endpoint, token)
+	app := NewAppWithSettings(
+		client, owner, name, config.ShowAll, config.Limit, config.RefreshInterval.Duration,
+		AppSettings{
+			FoldResolved:           config.Display.FoldResolved,
+			ThreadListWidthPercent: config.Display.ThreadListWidthPercent,
+			PathScroll:             config.Paths.Scroll,
+			PathScrollInterval:     config.Paths.ScrollInterval.Duration,
+		},
+	)
 	if _, err := tea.NewProgram(app, tea.WithAltScreen()).Run(); err != nil {
 		exitf("run TUI: %v", err)
 	}

markdown.go

@@ -11,6 +11,7 @@ import (
 
 var commentMarkdownRenderers sync.Map
 var quoteRailStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#777777"))
+var markdownStyleName = "dark"
 
 func renderCommentMarkdown(markdown string, width int) []string {
 	if strings.TrimSpace(markdown) == "" {
@@ -79,6 +80,9 @@ func commentMarkdownRenderer(width int) (*glamour.TermRenderer, error) {
 		return cached.(*glamour.TermRenderer), nil
 	}
 	style := styles.DarkStyleConfig
+	if markdownStyleName == "light" {
+		style = styles.LightStyleConfig
+	}
 	zero := uint(0)
 	style.Document.Margin = &zero
 	style.Code.Prefix = ""

theme.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/charmbracelet/lipgloss"
+)
+
+func applyTheme(name string) error {
+	switch name {
+	case "dark":
+		titleStyle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#F0B72F"))
+		dimStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#777777"))
+		activeStyle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#FFFFFF")).Background(lipgloss.Color("#3B4261"))
+		okStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#67C587"))
+		warnStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#E5C07B"))
+		badStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#E06C75"))
+		paneInactiveColor = lipgloss.Color("#50566F")
+		paneActiveColor = lipgloss.Color("#F0B72F")
+		authorPalette = []lipgloss.Color{
+			"#61AFEF", "#C678DD", "#56B6C2", "#E5C07B",
+			"#E06C75", "#98C379", "#D19A66", "#7FC8FF",
+		}
+		codeHighlightTheme = "github-dark"
+		markdownStyleName = "dark"
+		quoteRailStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#777777"))
+		selectedLineBackground = "\x1b[48;5;24m"
+		suggestionRemoveBackground = "\x1b[48;5;52m"
+		suggestionAddBackground = "\x1b[48;5;22m"
+		changedRemoveBackground = "\x1b[48;2;55;0;0m"
+		changedAddBackground = "\x1b[48;2;0;55;0m"
+	case "light":
+		titleStyle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#9A6700"))
+		dimStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#656D76"))
+		activeStyle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#FFFFFF")).Background(lipgloss.Color("#0969DA"))
+		okStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#1A7F37"))
+		warnStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#9A6700"))
+		badStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#CF222E"))
+		paneInactiveColor = lipgloss.Color("#8C959F")
+		paneActiveColor = lipgloss.Color("#0969DA")
+		authorPalette = []lipgloss.Color{
+			"#0550AE", "#8250DF", "#0A706F", "#9A6700",
+			"#CF222E", "#116329", "#953800", "#0969DA",
+		}
+		codeHighlightTheme = "github"
+		markdownStyleName = "light"
+		quoteRailStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("#656D76"))
+		selectedLineBackground = "\x1b[48;5;153m"
+		suggestionRemoveBackground = "\x1b[48;5;224m"
+		suggestionAddBackground = "\x1b[48;5;194m"
+		changedRemoveBackground = "\x1b[48;2;255;170;170m"
+		changedAddBackground = "\x1b[48;2;170;230;170m"
+	default:
+		return fmt.Errorf("unknown theme %q", name)
+	}
+	commentMarkdownRenderers.Clear()
+	return nil
+}

theme_test.go

@@ -0,0 +1,20 @@
+package main
+
+import "testing"
+
+func TestApplyThemeChangesAllRenderingThemes(t *testing.T) {
+	defer func() {
+		if err := applyTheme("dark"); err != nil {
+			t.Fatal(err)
+		}
+	}()
+	if err := applyTheme("light"); err != nil {
+		t.Fatal(err)
+	}
+	if markdownStyleName != "light" || codeHighlightTheme != "github" {
+		t.Fatalf("light theme did not propagate: markdown=%q code=%q", markdownStyleName, codeHighlightTheme)
+	}
+	if err := applyTheme("unknown"); err == nil {
+		t.Fatal("unknown theme was accepted")
+	}
+}

tui.go

@@ -28,6 +28,7 @@ const (
 )
 
 type tickMsg time.Time
+type pathTickMsg time.Time
 type prsLoadedMsg struct {
 	prs []PullRequest
 	err error
@@ -66,23 +67,65 @@ type App struct {
 	searchOrigin  int
 	helpVisible   bool
 	helpScroll    int
+
+	foldResolved           bool
+	threadListWidthPercent int
+	pathScroll             bool
+	pathScrollInterval     time.Duration
+	pathScrollStep         int
+}
+
+type AppSettings struct {
+	FoldResolved           bool
+	ThreadListWidthPercent int
+	PathScroll             bool
+	PathScrollInterval     time.Duration
+}
+
+func defaultAppSettings() AppSettings {
+	return AppSettings{
+		FoldResolved:           true,
+		ThreadListWidthPercent: 33,
+		PathScrollInterval:     350 * time.Millisecond,
+	}
 }
 
 func NewApp(service GitHubService, owner, repo string, showAll bool, limit int, poll time.Duration) App {
+	return NewAppWithSettings(service, owner, repo, showAll, limit, poll, defaultAppSettings())
+}
+
+func NewAppWithSettings(
+	service GitHubService,
+	owner, repo string,
+	showAll bool,
+	limit int,
+	poll time.Duration,
+	settings AppSettings,
+) App {
 	return App{
 		service: service, owner: owner, repo: repo, showAll: showAll, limit: limit, poll: poll,
 		folded: make(map[string]bool), loading: true,
+		foldResolved: settings.FoldResolved, threadListWidthPercent: settings.ThreadListWidthPercent,
+		pathScroll: settings.PathScroll, pathScrollInterval: settings.PathScrollInterval,
 	}
 }
 
 func (m App) Init() tea.Cmd {
-	return tea.Batch(m.loadPRs(), m.nextTick())
+	commands := []tea.Cmd{m.loadPRs(), m.nextTick()}
+	if m.pathScroll {
+		commands = append(commands, m.nextPathTick())
+	}
+	return tea.Batch(commands...)
 }
 
 func (m App) nextTick() tea.Cmd {
 	return tea.Tick(m.poll, func(t time.Time) tea.Msg { return tickMsg(t) })
 }
 
+func (m App) nextPathTick() tea.Cmd {
+	return tea.Tick(m.pathScrollInterval, func(t time.Time) tea.Msg { return pathTickMsg(t) })
+}
+
 func (m App) loadPRs() tea.Cmd {
 	return func() tea.Msg {
 		ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
@@ -117,6 +160,14 @@ func (m App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			return m, tea.Batch(m.loadPRs(), m.nextTick())
 		}
 		return m, m.nextTick()
+	case pathTickMsg:
+		if m.pathScroll && m.screen == threadScreen {
+			m.pathScrollStep++
+		}
+		if m.pathScroll {
+			return m, m.nextPathTick()
+		}
+		return m, nil
 	case prsLoadedMsg:
 		m.loading = false
 		if msg.err != nil {
@@ -158,7 +209,7 @@ func (m App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.scroll = 0
 		}
 		for _, thread := range m.details.Threads {
-			if _, set := m.folded[thread.ID]; !set && thread.IsResolved {
+			if _, set := m.folded[thread.ID]; !set && thread.IsResolved && m.foldResolved {
 				m.folded[thread.ID] = true
 			}
 		}
@@ -296,6 +347,7 @@ func (m App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.details = PRDetails{PullRequest: m.prs[m.prIndex]}
 			m.threadIndex, m.scroll, m.focus, m.listHidden, m.loading, m.err = 0, 0, threadListPane, false, true, nil
 			m.searching, m.searchQuery = false, ""
+			m.pathScrollStep = 0
 			return m, m.loadDetails(m.details.PullRequest)
 		}
 		if m.screen == threadScreen {
@@ -312,6 +364,7 @@ func (m App) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.details = PRDetails{PullRequest: m.prs[m.prIndex]}
 			m.threadIndex, m.scroll, m.focus, m.listHidden, m.loading, m.err = 0, 0, threadListPane, false, true, nil
 			m.searching, m.searchQuery = false, ""
+			m.pathScrollStep = 0
 			return m, m.loadDetails(m.details.PullRequest)
 		}
 		if m.screen == threadScreen && len(m.details.Threads) > 0 {
@@ -430,10 +483,18 @@ func (m App) detailPaneSize() (int, int) {
 	if m.width < 70 || m.listHidden {
 		return max(3, m.width), height
 	}
-	leftWidth := clamp(m.width/3, 30, 48)
+	leftWidth := m.threadListWidth()
 	return max(20, m.width-leftWidth-1), height
 }
 
+func (m App) threadListWidth() int {
+	percent := m.threadListWidthPercent
+	if percent == 0 {
+		percent = 33
+	}
+	return clamp(m.width*percent/100, 30, max(30, m.width-20))
+}
+
 func (m App) detailViewportHeight() int {
 	_, height := m.detailPaneSize()
 	return max(1, height-2)
@@ -533,18 +594,26 @@ func (m App) viewHelp() string {
 }
 
 var (
-	titleStyle  = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#F0B72F"))
-	dimStyle    = lipgloss.NewStyle().Foreground(lipgloss.Color("#777777"))
-	activeStyle = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#FFFFFF")).Background(lipgloss.Color("#3B4261"))
-	okStyle     = lipgloss.NewStyle().Foreground(lipgloss.Color("#67C587"))
-	warnStyle   = lipgloss.NewStyle().Foreground(lipgloss.Color("#E5C07B"))
-	badStyle    = lipgloss.NewStyle().Foreground(lipgloss.Color("#E06C75"))
+	titleStyle        = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#F0B72F"))
+	dimStyle          = lipgloss.NewStyle().Foreground(lipgloss.Color("#777777"))
+	activeStyle       = lipgloss.NewStyle().Bold(true).Foreground(lipgloss.Color("#FFFFFF")).Background(lipgloss.Color("#3B4261"))
+	okStyle           = lipgloss.NewStyle().Foreground(lipgloss.Color("#67C587"))
+	warnStyle         = lipgloss.NewStyle().Foreground(lipgloss.Color("#E5C07B"))
+	badStyle          = lipgloss.NewStyle().Foreground(lipgloss.Color("#E06C75"))
+	paneInactiveColor = lipgloss.Color("#50566F")
+	paneActiveColor   = lipgloss.Color("#F0B72F")
+
+	selectedLineBackground     = "\x1b[48;5;24m"
+	suggestionRemoveBackground = "\x1b[48;5;52m"
+	suggestionAddBackground    = "\x1b[48;5;22m"
+	changedRemoveBackground    = "\x1b[48;2;55;0;0m"
+	changedAddBackground       = "\x1b[48;2;0;55;0m"
 )
 
 func paneStyle(active bool) lipgloss.Style {
-	color := lipgloss.Color("#50566F")
+	color := paneInactiveColor
 	if active {
-		color = lipgloss.Color("#F0B72F")
+		color = paneActiveColor
 	}
 	return lipgloss.NewStyle().Border(lipgloss.RoundedBorder()).BorderForeground(color)
 }
@@ -636,7 +705,7 @@ func (m App) viewThreads() string {
 	} else if m.listHidden {
 		body = m.threadDetail(m.width, contentHeight)
 	} else {
-		leftWidth := clamp(m.width/3, 30, 48)
+		leftWidth := m.threadListWidth()
 		rightWidth := max(20, m.width-leftWidth-1)
 		left := m.threadList(leftWidth, contentHeight)
 		right := m.threadDetail(rightWidth, contentHeight)
@@ -684,7 +753,11 @@ func (m App) threadList(width, height int) string {
 		}
 		suffix := fmt.Sprintf(":%d · %d", thread.Line, len(thread.Comments))
 		pathWidth := max(4, innerWidth-lipgloss.Width(suffix)-2)
-		line := icon + " " + pad(truncatePath(thread.Path, pathWidth), pathWidth) + suffix
+		path := truncatePath(thread.Path, pathWidth)
+		if m.pathScroll {
+			path = scrollingPath(thread.Path, pathWidth, m.pathScrollStep)
+		}
+		line := icon + " " + pad(path, pathWidth) + suffix
 		line = ansi.Truncate(line, innerWidth, "")
 		if thread.IsResolved {
 			line = dimStyle.Render(line)
@@ -861,9 +934,9 @@ func highlightCodeRange(code string, changed codeRange, change byte) string {
 		return code
 	}
 
-	background := "\x1b[48;2;55;0;0m"
+	background := changedRemoveBackground
 	if change == '+' {
-		background = "\x1b[48;2;0;55;0m"
+		background = changedAddBackground
 	}
 	const reset = "\x1b[0m"
 	before := ansi.Cut(code, 0, start)
@@ -953,19 +1026,17 @@ func shortOID(oid string) string {
 }
 
 func selectedBackground(line string, width int) string {
-	const (
-		background = "\x1b[48;5;24m"
-		reset      = "\x1b[0m"
-	)
+	const reset = "\x1b[0m"
+	background := selectedLineBackground
 	line = pad(ansi.Truncate(line, width, ""), width)
 	line = strings.ReplaceAll(line, reset, reset+background)
 	return background + line + reset
 }
 
 func suggestionHighlight(gutter, code string, width int, change byte) string {
-	background := "\x1b[48;5;52m"
+	background := suggestionRemoveBackground
 	if change == '+' {
-		background = "\x1b[48;5;22m"
+		background = suggestionAddBackground
 	}
 	const reset = "\x1b[0m"
 	gutter = ansi.Truncate(gutter, width, "")
@@ -1138,6 +1209,41 @@ func truncatePath(path string, width int) string {
 	return "…" + ansi.Cut(path, pathWidth-width+1, pathWidth)
 }
 
+func scrollingPath(path string, width, step int) string {
+	const pauseSteps = 4
+	if width <= 0 {
+		return ""
+	}
+	pathWidth := ansi.StringWidth(path)
+	if pathWidth <= width {
+		return path
+	}
+	if width == 1 {
+		return "…"
+	}
+
+	visibleWidth := width - 1
+	maxOffset := pathWidth - visibleWidth
+	cycle := pauseSteps + maxOffset + pauseSteps
+	phase := step % cycle
+	offset := 0
+	switch {
+	case phase < pauseSteps:
+		offset = 0
+	case phase < pauseSteps+maxOffset:
+		offset = phase - pauseSteps
+	default:
+		offset = maxOffset
+	}
+	if offset == 0 {
+		return ansi.Cut(path, 0, visibleWidth) + "…"
+	}
+	if offset == maxOffset {
+		return "…" + ansi.Cut(path, pathWidth-visibleWidth, pathWidth)
+	}
+	return "…" + ansi.Cut(path, offset, offset+width-2) + "…"
+}
+
 func fuzzyPathScore(path, query string) (int, bool) {
 	candidate := []rune(strings.ToLower(path))
 	terms := strings.Fields(strings.ToLower(query))

tui_test.go

@@ -44,6 +44,20 @@ func TestResolvedThreadsStartFolded(t *testing.T) {
 	}
 }
 
+func TestResolvedThreadFoldingCanBeDisabled(t *testing.T) {
+	settings := defaultAppSettings()
+	settings.FoldResolved = false
+	m := NewAppWithSettings(nil, "o", "r", false, 50, 10*time.Second, settings)
+	m.details = PRDetails{PullRequest: PullRequest{Number: 7}}
+	updated, _ := m.Update(detailsLoadedMsg{number: 7, details: PRDetails{
+		PullRequest: PullRequest{Number: 7},
+		Threads:     []ReviewThread{{ID: "done", IsResolved: true}},
+	}})
+	if updated.(App).folded["done"] {
+		t.Fatal("resolved thread was folded despite configuration")
+	}
+}
+
 func TestResolvedThreadIconTakesPrecedenceOverOutdated(t *testing.T) {
 	m := NewApp(nil, "o", "r", false, 50, 10*time.Second)
 	m.details = PRDetails{Threads: []ReviewThread{{
@@ -181,6 +195,36 @@ func TestTruncatePathPreservesFilename(t *testing.T) {
 	}
 }
 
+func TestConfiguredPathScrollingAdvances(t *testing.T) {
+	settings := defaultAppSettings()
+	settings.PathScroll = true
+	settings.PathScrollInterval = 100 * time.Millisecond
+	m := NewAppWithSettings(nil, "o", "r", false, 50, 10*time.Second, settings)
+	m.screen = threadScreen
+	updated, _ := m.Update(pathTickMsg(time.Now()))
+	if got := updated.(App).pathScrollStep; got != 1 {
+		t.Fatalf("path scroll step = %d, want 1", got)
+	}
+
+	path := "internal/review/threads/important_filename.go"
+	if beginning := scrollingPath(path, 18, 0); !strings.HasPrefix(beginning, "internal/") {
+		t.Fatalf("scroll beginning = %q", beginning)
+	}
+	if end := scrollingPath(path, 18, 1000); ansi.StringWidth(end) != 18 {
+		t.Fatalf("scroll output has width %d", ansi.StringWidth(end))
+	}
+}
+
+func TestConfiguredThreadListWidth(t *testing.T) {
+	settings := defaultAppSettings()
+	settings.ThreadListWidthPercent = 50
+	m := NewAppWithSettings(nil, "o", "r", false, 50, 10*time.Second, settings)
+	m.width = 120
+	if got := m.threadListWidth(); got != 60 {
+		t.Fatalf("thread list width = %d, want 60", got)
+	}
+}
+
 func TestFuzzyFileSearchRanksAndFiltersPaths(t *testing.T) {
 	m := NewApp(nil, "o", "r", false, 50, 10*time.Second)
 	m.searchQuery = "svcusr"