feat: add configurable preview position (right/bottom/left/top)

README.md

@@ -180,6 +180,7 @@ dispatch
 | `S` | Toggle sort direction |
 | `Tab` | Cycle grouping mode |
 | `p` | Toggle preview panel |
+| `P` | Cycle preview position (right → bottom → left → top) |
 | `PgUp` / `PgDn` | Scroll preview |
 | `r` | Refresh session store |
 | `,` | Open settings panel |
@@ -248,6 +249,7 @@ Configuration is stored in the platform-specific config directory:
 | `default_sort` | string | `"updated"` | Sort field: `updated`, `created`, `turns`, `name`, `folder` |
 | `default_pivot` | string | `"folder"` | Grouping: `none`, `folder`, `repo`, `branch`, `date` |
 | `show_preview` | bool | `true` | Show preview pane on startup |
+| `preview_position` | string | `"right"` | Position of the preview pane: `right`, `bottom`, `left`, `top` |
 | `max_sessions` | int | `100` | Maximum sessions to load |
 | `yoloMode` | bool | `false` | Pass `--allow-all` to Copilot CLI (auto-confirm commands) |
 | `agent` | string | `""` | Pass `--agent <name>` to Copilot CLI |
@@ -272,6 +274,7 @@ Configuration is stored in the platform-specific config directory:
   "default_sort": "updated",
   "default_pivot": "folder",
   "show_preview": true,
+  "preview_position": "right",
   "max_sessions": 100,
   "yoloMode": false,
   "agent": "",

internal/config/config.go

@@ -130,6 +130,12 @@ type Config struct {
 	// format.  Users can paste any WT scheme JSON directly here.
 	Schemes []styles.ColorScheme `json:"schemes,omitempty"`
 
+	// PreviewPosition controls where the session detail/preview panel
+	// is displayed relative to the session list.
+	// Valid values: "right", "bottom", "left", "top".
+	// Default is "right" when unset.
+	PreviewPosition string `json:"preview_position,omitempty"`
+
 	// ConversationNewestFirst controls the turn display order in the
 	// preview panel's Conversation section. When false (default), turns
 	// are shown oldest-first (ascending by TurnIndex). When true, turns
@@ -170,6 +176,18 @@ const (
 	PaneDirectionUp = "up"
 )
 
+// PreviewPosition constants control where the preview panel is displayed.
+const (
+	// PreviewPositionRight places the preview to the right of the session list.
+	PreviewPositionRight = "right"
+	// PreviewPositionBottom places the preview below the session list.
+	PreviewPositionBottom = "bottom"
+	// PreviewPositionLeft places the preview to the left of the session list.
+	PreviewPositionLeft = "left"
+	// PreviewPositionTop places the preview above the session list.
+	PreviewPositionTop = "top"
+)
+
 // EffectivePaneDirection returns the configured pane direction, defaulting
 // to "auto" when unset.
 func (c *Config) EffectivePaneDirection() string {
@@ -179,6 +197,17 @@ func (c *Config) EffectivePaneDirection() string {
 	return PaneDirectionAuto
 }
 
+// EffectivePreviewPosition returns the configured preview panel position,
+// defaulting to "right" when unset or invalid.
+func (c *Config) EffectivePreviewPosition() string {
+	switch c.PreviewPosition {
+	case PreviewPositionRight, PreviewPositionBottom, PreviewPositionLeft, PreviewPositionTop:
+		return c.PreviewPosition
+	default:
+		return PreviewPositionRight
+	}
+}
+
 // defaultAttentionThreshold is used when AttentionThreshold is empty or unparseable.
 const defaultAttentionThreshold = 15 * time.Minute
 

internal/config/config_test.go

@@ -60,6 +60,9 @@ func TestDefaultValues(t *testing.T) {
 	if !cfg.WorkspaceRecovery {
 		t.Error("WorkspaceRecovery should default to true")
 	}
+	if cfg.PreviewPosition != "" {
+		t.Errorf("PreviewPosition = %q, want empty", cfg.PreviewPosition)
+	}
 }
 
 // ---------------------------------------------------------------------------
@@ -82,6 +85,7 @@ func TestConfigJSONRoundTrip(t *testing.T) {
 		ExcludedDirs:     []string{"/tmp", "/var"},
 		CustomCommand:    "ghcs --resume {sessionId} --custom",
 		HiddenSessions:   []string{"sess-1", "sess-2"},
+		PreviewPosition:  "bottom",
 	}
 
 	data, err := json.Marshal(original)
@@ -146,6 +150,9 @@ func TestConfigJSONRoundTrip(t *testing.T) {
 			t.Errorf("HiddenSessions[%d] = %q, want %q", i, restored.HiddenSessions[i], original.HiddenSessions[i])
 		}
 	}
+	if restored.PreviewPosition != original.PreviewPosition {
+		t.Errorf("PreviewPosition = %q, want %q", restored.PreviewPosition, original.PreviewPosition)
+	}
 }
 
 func TestWorkspaceRecoveryJSONFalse(t *testing.T) {
@@ -1035,3 +1042,72 @@ func TestLoad_SanitizesUnsafeShellOnDisk(t *testing.T) {
 		t.Errorf("DefaultTerminal = %q, want empty after sanitize", cfg.DefaultTerminal)
 	}
 }
+
+// ---------------------------------------------------------------------------
+// EffectivePreviewPosition tests
+// ---------------------------------------------------------------------------
+
+func TestEffectivePreviewPosition_Default(t *testing.T) {
+	cfg := Default()
+	if got := cfg.EffectivePreviewPosition(); got != PreviewPositionRight {
+		t.Errorf("default config: got %q, want %q", got, PreviewPositionRight)
+	}
+}
+
+func TestEffectivePreviewPosition_EmptyDefaultsToRight(t *testing.T) {
+	cfg := &Config{}
+	if got := cfg.EffectivePreviewPosition(); got != PreviewPositionRight {
+		t.Errorf("empty PreviewPosition: got %q, want %q", got, PreviewPositionRight)
+	}
+}
+
+func TestEffectivePreviewPosition_InvalidDefaultsToRight(t *testing.T) {
+	cfg := &Config{PreviewPosition: "invalid"}
+	if got := cfg.EffectivePreviewPosition(); got != PreviewPositionRight {
+		t.Errorf("invalid PreviewPosition: got %q, want %q", got, PreviewPositionRight)
+	}
+}
+
+func TestEffectivePreviewPosition_ExplicitValues(t *testing.T) {
+	tests := []struct {
+		pos  string
+		want string
+	}{
+		{PreviewPositionRight, PreviewPositionRight},
+		{PreviewPositionBottom, PreviewPositionBottom},
+		{PreviewPositionLeft, PreviewPositionLeft},
+		{PreviewPositionTop, PreviewPositionTop},
+	}
+	for _, tt := range tests {
+		cfg := &Config{PreviewPosition: tt.pos}
+		if got := cfg.EffectivePreviewPosition(); got != tt.want {
+			t.Errorf("PreviewPosition=%q: got %q, want %q", tt.pos, got, tt.want)
+		}
+	}
+}
+
+func TestEffectivePreviewPosition_JSONRoundTrip(t *testing.T) {
+	jsonStr := `{"preview_position": "bottom"}`
+	cfg := Default()
+	if err := json.Unmarshal([]byte(jsonStr), cfg); err != nil {
+		t.Fatal(err)
+	}
+	if got := cfg.EffectivePreviewPosition(); got != PreviewPositionBottom {
+		t.Errorf("JSON preview_position: got %q, want %q", got, PreviewPositionBottom)
+	}
+}
+
+func TestPreviewPositionConstants(t *testing.T) {
+	if PreviewPositionRight != "right" {
+		t.Errorf("PreviewPositionRight = %q, want 'right'", PreviewPositionRight)
+	}
+	if PreviewPositionBottom != "bottom" {
+		t.Errorf("PreviewPositionBottom = %q, want 'bottom'", PreviewPositionBottom)
+	}
+	if PreviewPositionLeft != "left" {
+		t.Errorf("PreviewPositionLeft = %q, want 'left'", PreviewPositionLeft)
+	}
+	if PreviewPositionTop != "top" {
+		t.Errorf("PreviewPositionTop = %q, want 'top'", PreviewPositionTop)
+	}
+}

internal/tui/components/configpanel.go

@@ -30,6 +30,7 @@ const (
 	cfgCustomCommand
 	cfgTheme
 	cfgWorkspaceRecovery
+	cfgPreviewPosition
 	cfgFieldCount
 )
 
@@ -50,6 +51,7 @@ type ConfigPanel struct {
 	customCommand     string
 	theme             string // active color scheme name ("auto" or a scheme name)
 	workspaceRecovery bool
+	previewPosition   string // "right", "bottom", "left", "top"
 
 	// Available options for cycling.
 	terminals  []string
@@ -89,6 +91,7 @@ type ConfigValues struct {
 	CustomCommand     string
 	Theme             string
 	WorkspaceRecovery bool
+	PreviewPosition   string
 }
 
 // SetValues loads the config panel state from external values.
@@ -103,6 +106,7 @@ func (c *ConfigPanel) SetValues(v ConfigValues) {
 	c.customCommand = v.CustomCommand
 	c.theme = v.Theme
 	c.workspaceRecovery = v.WorkspaceRecovery
+	c.previewPosition = v.PreviewPosition
 }
 
 // Values returns the current state of all editable fields.
@@ -118,6 +122,7 @@ func (c *ConfigPanel) Values() ConfigValues {
 		CustomCommand:     c.customCommand,
 		Theme:             c.theme,
 		WorkspaceRecovery: c.workspaceRecovery,
+		PreviewPosition:   c.previewPosition,
 	}
 }
 
@@ -206,6 +211,8 @@ func (c *ConfigPanel) HandleEnter() tea.Cmd {
 		c.theme = c.cycleTheme(c.theme)
 	case cfgWorkspaceRecovery:
 		c.workspaceRecovery = !c.workspaceRecovery
+	case cfgPreviewPosition:
+		c.previewPosition = cyclePreviewPosition(c.previewPosition)
 	default:
 		// cfgFieldCount is a sentinel; no action needed.
 	}
@@ -277,6 +284,7 @@ func (c ConfigPanel) View() string {
 		{"Custom Command", stringDisplay(c.customCommand), false},
 		{"Theme", themeDisplay(c.theme), false},
 		{"Crash Recovery", boolDisplay(c.workspaceRecovery), false},
+		{"Preview Position", previewPositionDisplay(c.previewPosition), false},
 	}
 
 	var body strings.Builder
@@ -459,3 +467,33 @@ func (c *ConfigPanel) cycleTheme(current string) string {
 	}
 	return c.themeNames[0]
 }
+
+// cyclePreviewPosition cycles through the four preview positions.
+func cyclePreviewPosition(current string) string {
+	switch current {
+	case config.PreviewPositionRight:
+		return config.PreviewPositionBottom
+	case config.PreviewPositionBottom:
+		return config.PreviewPositionLeft
+	case config.PreviewPositionLeft:
+		return config.PreviewPositionTop
+	case config.PreviewPositionTop:
+		return config.PreviewPositionRight
+	default:
+		return config.PreviewPositionBottom
+	}
+}
+
+// previewPositionDisplay renders the preview position as a user-friendly label.
+func previewPositionDisplay(pos string) string {
+	switch pos {
+	case config.PreviewPositionBottom:
+		return styles.ConfigValueStyle.Render("Bottom")
+	case config.PreviewPositionLeft:
+		return styles.ConfigValueStyle.Render("Left")
+	case config.PreviewPositionTop:
+		return styles.ConfigValueStyle.Render("Top")
+	default:
+		return styles.ConfigValueStyle.Render("Right")
+	}
+}

internal/tui/components/configpanel_test.go

@@ -34,7 +34,7 @@ func TestConfigPanel_SetValues_RoundTrip(t *testing.T) {
 	cp.SetValues(ConfigValues{
 		YoloMode: true, Agent: "myagent", Model: "gpt-4", LaunchMode: "tab",
 		Terminal: "Windows Terminal", Shell: "pwsh", CustomCommand: "my-cmd {sessionId}", Theme: "Campbell",
-		WorkspaceRecovery: true,
+		WorkspaceRecovery: true, PreviewPosition: "bottom",
 	})
 
 	v := cp.Values()
@@ -65,6 +65,9 @@ func TestConfigPanel_SetValues_RoundTrip(t *testing.T) {
 	if !v.WorkspaceRecovery {
 		t.Error("workspaceRecovery should be true")
 	}
+	if v.PreviewPosition != "bottom" {
+		t.Errorf("previewPosition = %q, want %q", v.PreviewPosition, "bottom")
+	}
 }
 
 // ---------------------------------------------------------------------------
@@ -152,6 +155,36 @@ func TestConfigPanel_HandleEnter_WorkspaceRecoveryToggle(t *testing.T) {
 	}
 }
 
+func TestConfigPanel_HandleEnter_PreviewPositionCycle(t *testing.T) {
+	cp := NewConfigPanel()
+	cp.SetValues(ConfigValues{PreviewPosition: "right"})
+	cp.cursor = cfgPreviewPosition
+
+	// right → bottom
+	cp.HandleEnter()
+	if pos := cp.Values().PreviewPosition; pos != "bottom" {
+		t.Errorf("after cycling from right, pos = %q, want %q", pos, "bottom")
+	}
+
+	// bottom → left
+	cp.HandleEnter()
+	if pos := cp.Values().PreviewPosition; pos != "left" {
+		t.Errorf("after cycling from bottom, pos = %q, want %q", pos, "left")
+	}
+
+	// left → top
+	cp.HandleEnter()
+	if pos := cp.Values().PreviewPosition; pos != "top" {
+		t.Errorf("after cycling from left, pos = %q, want %q", pos, "top")
+	}
+
+	// top → right (wraps around)
+	cp.HandleEnter()
+	if pos := cp.Values().PreviewPosition; pos != "right" {
+		t.Errorf("after cycling from top, pos = %q, want %q", pos, "right")
+	}
+}
+
 func TestConfigPanel_HandleEnter_LaunchModeCycle(t *testing.T) {
 	cp := NewConfigPanel()
 	cp.SetValues(ConfigValues{LaunchMode: "window"})
@@ -305,7 +338,7 @@ func TestConfigPanel_View_ContainsFields(t *testing.T) {
 	cp := NewConfigPanel()
 	cp.SetSize(80, 40)
 	view := cp.View()
-	for _, field := range []string{"Yolo Mode", "Agent", "Model", "Launch Mode", "Terminal", "Shell", "Custom Command", "Theme", "Crash Recovery"} {
+	for _, field := range []string{"Yolo Mode", "Agent", "Model", "Launch Mode", "Terminal", "Shell", "Custom Command", "Theme", "Crash Recovery", "Preview Position"} {
 		if !strings.Contains(view, field) {
 			t.Errorf("View should contain field %q", field)
 		}
@@ -411,3 +444,47 @@ func TestThemeDisplay(t *testing.T) {
 		}
 	}
 }
+
+// ---------------------------------------------------------------------------
+// Preview position helpers
+// ---------------------------------------------------------------------------
+
+func TestCyclePreviewPosition(t *testing.T) {
+	tests := []struct {
+		current string
+		want    string
+	}{
+		{"right", "bottom"},
+		{"bottom", "left"},
+		{"left", "top"},
+		{"top", "right"},
+		{"", "bottom"},        // default/empty cycles to bottom
+		{"invalid", "bottom"}, // invalid cycles to bottom
+	}
+	for _, tt := range tests {
+		got := cyclePreviewPosition(tt.current)
+		if got != tt.want {
+			t.Errorf("cyclePreviewPosition(%q) = %q, want %q", tt.current, got, tt.want)
+		}
+	}
+}
+
+func TestPreviewPositionDisplay(t *testing.T) {
+	tests := []struct {
+		pos  string
+		want string
+	}{
+		{"right", "Right"},
+		{"bottom", "Bottom"},
+		{"left", "Left"},
+		{"top", "Top"},
+		{"", "Right"},        // default shows Right
+		{"invalid", "Right"}, // invalid shows Right
+	}
+	for _, tt := range tests {
+		got := previewPositionDisplay(tt.pos)
+		if !strings.Contains(got, tt.want) {
+			t.Errorf("previewPositionDisplay(%q) = %q, want to contain %q", tt.pos, got, tt.want)
+		}
+	}
+}

internal/tui/components/preview.go

@@ -9,7 +9,7 @@ import (
 	"github.com/jongio/dispatch/internal/tui/styles"
 )
 
-// PreviewPanel renders a right-side detail panel for the selected session.
+// PreviewPanel renders a detail panel for the selected session.
 type PreviewPanel struct {
 	detail          *data.SessionDetail
 	attentionStatus data.AttentionStatus