feat(layout): add position-aware InsertPaneAfter for stacked views

Implement InsertPaneAfter method to insert new panes immediately after the
current active pane, rather than always appending to the end. Update
StackedPaneManager to use this new method. Includes comprehensive tests for
position-aware insertion behavior with various edge cases.

commit: 6f9d17f4fadd86cb0fe39cc7bc84685ffc3b4e57
author: brice · 10mo ago · 2025-12-17 22:25 UTC
committer: brice · 10mo ago · 2025-12-17 20:36 UTC
parent: 786d68a
signature: unsigned

3 files · +384 -3

M internal/ui/component/stacked_pane_manager.go +7 -3


@@ -60,19 +60,23 @@ func (spm *StackedPaneManager) AddPaneToStack(
60	60		widget.Unparent()
61	61		}
62	62
63		-	// Add to the stack (this makes it active automatically)
	63	+	// Add to the stack after the current active pane (not at end)
64	64		if title == "" {
65	65		title = "Untitled"
66	66		}
67	67
	68	+	// Get current active index to insert after it
	69	+	currentActiveIndex := stackedView.ActiveIndex()
	70	+
68	71		log.Debug().
69	72		Str("active_pane", string(activePaneID)).
70	73		Str("new_pane", string(newPaneView.PaneID())).
71	74		Str("title", title).
	75	+	Int("current_active_index", currentActiveIndex).
72	76		Int("stack_size_before", stackedView.Count()).
73		-	Msg("StackedPaneManager: adding pane to stack")
	77	+	Msg("StackedPaneManager: inserting pane after active position")
74	78
75		-	stackedView.AddPane(ctx, title, "", widget)
	79	+	stackedView.InsertPaneAfter(ctx, currentActiveIndex, title, "", widget)
76	80
77	81		// Register the new pane in the TreeRenderer's tracking
78	82		tr.RegisterPaneInStack(string(newPaneView.PaneID()), stackedView)

 		widget.Unparent()
 	}
-	// Add to the stack (this makes it active automatically)
+	// Add to the stack after the current active pane (not at end)
 	if title == "" {
 		title = "Untitled"
 	}
+	// Get current active index to insert after it
+	currentActiveIndex := stackedView.ActiveIndex()
 	log.Debug().
 		Str("active_pane", string(activePaneID)).
 		Str("new_pane", string(newPaneView.PaneID())).
 		Str("title", title).
+		Int("current_active_index", currentActiveIndex).
 		Int("stack_size_before", stackedView.Count()).
-		Msg("StackedPaneManager: adding pane to stack")
+		Msg("StackedPaneManager: inserting pane after active position")
-	stackedView.AddPane(ctx, title, "", widget)
+	stackedView.InsertPaneAfter(ctx, currentActiveIndex, title, "", widget)
 	// Register the new pane in the TreeRenderer's tracking
 	tr.RegisterPaneInStack(string(newPaneView.PaneID()), stackedView)

M internal/ui/layout/stacked.go +128 -0


@@ -141,6 +141,134 @@ func (sv *StackedView) AddPane(ctx context.Context, title, faviconIconName strin
141	141		return index
142	142		}
143	143
	144	+	// InsertPaneAfter inserts a new pane after the specified index position.
	145	+	// Use afterIndex=-1 to insert at the beginning.
	146	+	// The new pane becomes active (visible).
	147	+	// Returns the index where the pane was inserted.
	148	+	func (sv *StackedView) InsertPaneAfter(
	149	+	ctx context.Context, afterIndex int, title, faviconIconName string, container Widget,
	150	+	) int {
	151	+	log := logging.FromContext(ctx)
	152	+	sv.mu.Lock()
	153	+	defer sv.mu.Unlock()
	154	+
	155	+	// Validate afterIndex - clamp to valid range
	156	+	if afterIndex < -1 {
	157	+	afterIndex = -1
	158	+	}
	159	+	if afterIndex >= len(sv.panes) {
	160	+	afterIndex = len(sv.panes) - 1
	161	+	}
	162	+	insertIndex := afterIndex + 1
	163	+
	164	+	log.Debug().
	165	+	Str("title", title).
	166	+	Int("after_index", afterIndex).
	167	+	Int("insert_index", insertIndex).
	168	+	Int("current_count", len(sv.panes)).
	169	+	Msg("StackedView.InsertPaneAfter called")
	170	+
	171	+	// Create title bar - must not expand vertically
	172	+	titleBar := sv.factory.NewBox(OrientationHorizontal, 4)
	173	+	titleBar.AddCssClass("stacked-pane-titlebar")
	174	+	titleBar.SetVexpand(false)
	175	+
	176	+	// Create favicon image
	177	+	favicon := sv.factory.NewImage()
	178	+	if faviconIconName != "" {
	179	+	favicon.SetFromIconName(faviconIconName)
	180	+	} else {
	181	+	favicon.SetFromIconName("web-browser-symbolic")
	182	+	}
	183	+	favicon.SetPixelSize(16)
	184	+	titleBar.Append(favicon)
	185	+
	186	+	// Create title label
	187	+	label := sv.factory.NewLabel(title)
	188	+	label.SetEllipsize(EllipsizeEnd)
	189	+	label.SetMaxWidthChars(30)
	190	+	label.SetHexpand(true)
	191	+	label.SetXalign(0.0)
	192	+	titleBar.Append(label)
	193	+
	194	+	// Make title bar clickable - ensure it doesn't expand vertically
	195	+	titleButton := sv.factory.NewButton()
	196	+	titleButton.SetChild(titleBar)
	197	+	titleButton.AddCssClass("stacked-pane-title-button")
	198	+	titleButton.SetFocusOnClick(false)
	199	+	titleButton.SetVexpand(false)
	200	+	titleButton.SetHexpand(true)
	201	+
	202	+	pane := &stackedPane{
	203	+	titleBar: titleBar,
	204	+	container: container,
	205	+	title: title,
	206	+	favicon: favicon,
	207	+	label: label,
	208	+	isActive: false,
	209	+	}
	210	+
	211	+	// Insert into slice at correct position
	212	+	sv.panes = append(sv.panes, nil)
	213	+	copy(sv.panes[insertIndex+1:], sv.panes[insertIndex:])
	214	+	sv.panes[insertIndex] = pane
	215	+
	216	+	// Connect click handler - use captured index
	217	+	capturedIndex := insertIndex
	218	+	titleButton.ConnectClicked(func() {
	219	+	sv.mu.RLock()
	220	+	callback := sv.onActivate
	221	+	sv.mu.RUnlock()
	222	+
	223	+	if callback != nil {
	224	+	callback(capturedIndex)
	225	+	}
	226	+	})
	227	+
	228	+	// Insert widgets at correct position in GTK box
	229	+	if insertIndex > 0 && sv.panes[insertIndex-1] != nil {
	230	+	// Insert after the previous pane's container
	231	+	prevPane := sv.panes[insertIndex-1]
	232	+	if prevPane.container != nil {
	233	+	sv.box.InsertChildAfter(titleButton, prevPane.container)
	234	+	if container != nil {
	235	+	sv.box.InsertChildAfter(container, titleButton)
	236	+	}
	237	+	} else {
	238	+	// No container, insert after title bar's parent (the button)
	239	+	prevTitleParent := prevPane.titleBar.GetParent()
	240	+	if prevTitleParent != nil {
	241	+	sv.box.InsertChildAfter(titleButton, prevTitleParent)
	242	+	if container != nil {
	243	+	sv.box.InsertChildAfter(container, titleButton)
	244	+	}
	245	+	} else {
	246	+	// Fallback to append
	247	+	sv.box.Append(titleButton)
	248	+	if container != nil {
	249	+	sv.box.Append(container)
	250	+	}
	251	+	}
	252	+	}
	253	+	} else {
	254	+	// Insert at beginning
	255	+	if container != nil {
	256	+	sv.box.Prepend(container)
	257	+	}
	258	+	sv.box.Prepend(titleButton)
	259	+	}
	260	+
	261	+	// Set this pane as active
	262	+	sv.setActiveInternal(ctx, insertIndex)
	263	+
	264	+	log.Debug().
	265	+	Int("insert_index", insertIndex).
	266	+	Int("new_count", len(sv.panes)).
	267	+	Msg("StackedView.InsertPaneAfter completed")
	268	+
	269	+	return insertIndex
	270	+	}
	271	+
144	272		// RemovePane removes a pane from the stack by index.
145	273		// Returns an error if trying to remove the last pane.
146	274		func (sv *StackedView) RemovePane(ctx context.Context, index int) error {


@@ -141,6 +141,134 @@ func (sv *StackedView) AddPane(ctx context.Context, title, faviconIconName strin
141	return index	141		return index
142	}	142		}
143		143
		144	+	// InsertPaneAfter inserts a new pane after the specified index position.
		145	+	// Use afterIndex=-1 to insert at the beginning.
		146	+	// The new pane becomes active (visible).
		147	+	// Returns the index where the pane was inserted.
		148	+	func (sv *StackedView) InsertPaneAfter(
		149	+	ctx context.Context, afterIndex int, title, faviconIconName string, container Widget,
		150	+	) int {
		151	+	log := logging.FromContext(ctx)
		152	+	sv.mu.Lock()
		153	+	defer sv.mu.Unlock()
		154	+
		155	+	// Validate afterIndex - clamp to valid range
		156	+	if afterIndex < -1 {
		157	+	afterIndex = -1
		158	+	}
		159	+	if afterIndex >= len(sv.panes) {
		160	+	afterIndex = len(sv.panes) - 1
		161	+	}
		162	+	insertIndex := afterIndex + 1
		163	+
		164	+	log.Debug().
		165	+	Str("title", title).
		166	+	Int("after_index", afterIndex).
		167	+	Int("insert_index", insertIndex).
		168	+	Int("current_count", len(sv.panes)).
		169	+	Msg("StackedView.InsertPaneAfter called")
		170	+
		171	+	// Create title bar - must not expand vertically
		172	+	titleBar := sv.factory.NewBox(OrientationHorizontal, 4)
		173	+	titleBar.AddCssClass("stacked-pane-titlebar")
		174	+	titleBar.SetVexpand(false)
		175	+
		176	+	// Create favicon image
		177	+	favicon := sv.factory.NewImage()
		178	+	if faviconIconName != "" {
		179	+	favicon.SetFromIconName(faviconIconName)
		180	+	} else {
		181	+	favicon.SetFromIconName("web-browser-symbolic")
		182	+	}
		183	+	favicon.SetPixelSize(16)
		184	+	titleBar.Append(favicon)
		185	+
		186	+	// Create title label
		187	+	label := sv.factory.NewLabel(title)
		188	+	label.SetEllipsize(EllipsizeEnd)
		189	+	label.SetMaxWidthChars(30)
		190	+	label.SetHexpand(true)
		191	+	label.SetXalign(0.0)
		192	+	titleBar.Append(label)
		193	+
		194	+	// Make title bar clickable - ensure it doesn't expand vertically
		195	+	titleButton := sv.factory.NewButton()
		196	+	titleButton.SetChild(titleBar)
		197	+	titleButton.AddCssClass("stacked-pane-title-button")
		198	+	titleButton.SetFocusOnClick(false)
		199	+	titleButton.SetVexpand(false)
		200	+	titleButton.SetHexpand(true)
		201	+
		202	+	pane := &stackedPane{
		203	+	titleBar: titleBar,
		204	+	container: container,
		205	+	title: title,
		206	+	favicon: favicon,
		207	+	label: label,
		208	+	isActive: false,
		209	+	}
		210	+
		211	+	// Insert into slice at correct position
		212	+	sv.panes = append(sv.panes, nil)
		213	+	copy(sv.panes[insertIndex+1:], sv.panes[insertIndex:])
		214	+	sv.panes[insertIndex] = pane
		215	+
		216	+	// Connect click handler - use captured index
		217	+	capturedIndex := insertIndex
		218	+	titleButton.ConnectClicked(func() {
		219	+	sv.mu.RLock()
		220	+	callback := sv.onActivate
		221	+	sv.mu.RUnlock()
		222	+
		223	+	if callback != nil {
		224	+	callback(capturedIndex)
		225	+	}
		226	+	})
		227	+
		228	+	// Insert widgets at correct position in GTK box
		229	+	if insertIndex > 0 && sv.panes[insertIndex-1] != nil {
		230	+	// Insert after the previous pane's container
		231	+	prevPane := sv.panes[insertIndex-1]
		232	+	if prevPane.container != nil {
		233	+	sv.box.InsertChildAfter(titleButton, prevPane.container)
		234	+	if container != nil {
		235	+	sv.box.InsertChildAfter(container, titleButton)
		236	+	}
		237	+	} else {
		238	+	// No container, insert after title bar's parent (the button)
		239	+	prevTitleParent := prevPane.titleBar.GetParent()
		240	+	if prevTitleParent != nil {
		241	+	sv.box.InsertChildAfter(titleButton, prevTitleParent)
		242	+	if container != nil {
		243	+	sv.box.InsertChildAfter(container, titleButton)
		244	+	}
		245	+	} else {
		246	+	// Fallback to append
		247	+	sv.box.Append(titleButton)
		248	+	if container != nil {
		249	+	sv.box.Append(container)
		250	+	}
		251	+	}
		252	+	}
		253	+	} else {
		254	+	// Insert at beginning
		255	+	if container != nil {
		256	+	sv.box.Prepend(container)
		257	+	}
		258	+	sv.box.Prepend(titleButton)
		259	+	}
		260	+
		261	+	// Set this pane as active
		262	+	sv.setActiveInternal(ctx, insertIndex)
		263	+
		264	+	log.Debug().
		265	+	Int("insert_index", insertIndex).
		266	+	Int("new_count", len(sv.panes)).
		267	+	Msg("StackedView.InsertPaneAfter completed")
		268	+
		269	+	return insertIndex
		270	+	}
		271	+
144	// RemovePane removes a pane from the stack by index.	272		// RemovePane removes a pane from the stack by index.
145	// Returns an error if trying to remove the last pane.	273		// Returns an error if trying to remove the last pane.
146	func (sv *StackedView) RemovePane(ctx context.Context, index int) error {	274		func (sv *StackedView) RemovePane(ctx context.Context, index int) error {

M internal/ui/layout/stacked_test.go +249 -0


@@ -504,3 +504,252 @@ func TestSetOnActivate_Callback(t *testing.T) {
504	504		// simulating a button click. The test verifies the method doesn't panic.
505	505		// Integration tests would verify the actual callback invocation.
506	506		}
	507	+
	508	+	// setupInsertPaneMocks creates mocks needed for InsertPaneAfter with position-aware insertion.
	509	+	// Returns only the titleBar and container mocks that are needed by test assertions.
	510	+	func setupInsertPaneMocks(
	511	+	t *testing.T,
	512	+	mockFactory *mocks.MockWidgetFactory,
	513	+	mockBox *mocks.MockBoxWidget,
	514	+	siblingContainer layout.Widget,
	515	+	) (mocks.MockBoxWidget, mocks.MockWidget) {
	516	+	mockTitleBar := mocks.NewMockBoxWidget(t)
	517	+	mockFavicon := mocks.NewMockImageWidget(t)
	518	+	mockLabel := mocks.NewMockLabelWidget(t)
	519	+	mockButton := mocks.NewMockButtonWidget(t)
	520	+	mockContainer := mocks.NewMockWidget(t)
	521	+
	522	+	// Title bar creation
	523	+	mockFactory.EXPECT().NewBox(layout.OrientationHorizontal, 4).Return(mockTitleBar).Once()
	524	+	mockTitleBar.EXPECT().AddCssClass("stacked-pane-titlebar").Once()
	525	+	mockTitleBar.EXPECT().SetVexpand(false).Once()
	526	+
	527	+	// Favicon
	528	+	mockFactory.EXPECT().NewImage().Return(mockFavicon).Once()
	529	+	mockFavicon.EXPECT().SetFromIconName(mock.Anything).Once()
	530	+	mockFavicon.EXPECT().SetPixelSize(16).Once()
	531	+	mockTitleBar.EXPECT().Append(mockFavicon).Once()
	532	+
	533	+	// Label
	534	+	mockFactory.EXPECT().NewLabel(mock.Anything).Return(mockLabel).Once()
	535	+	mockLabel.EXPECT().SetEllipsize(layout.EllipsizeEnd).Once()
	536	+	mockLabel.EXPECT().SetMaxWidthChars(30).Once()
	537	+	mockLabel.EXPECT().SetHexpand(true).Once()
	538	+	mockLabel.EXPECT().SetXalign(float32(0.0)).Once()
	539	+	mockTitleBar.EXPECT().Append(mockLabel).Once()
	540	+
	541	+	// Button wrapping title bar
	542	+	mockFactory.EXPECT().NewButton().Return(mockButton).Once()
	543	+	mockButton.EXPECT().SetChild(mockTitleBar).Once()
	544	+	mockButton.EXPECT().AddCssClass("stacked-pane-title-button").Once()
	545	+	mockButton.EXPECT().SetFocusOnClick(false).Once()
	546	+	mockButton.EXPECT().SetVexpand(false).Once()
	547	+	mockButton.EXPECT().SetHexpand(true).Once()
	548	+	mockButton.EXPECT().ConnectClicked(mock.Anything).Return(uint32(1)).Once()
	549	+
	550	+	// Position-aware insertion using InsertChildAfter
	551	+	if siblingContainer != nil {
	552	+	mockBox.EXPECT().InsertChildAfter(mockButton, siblingContainer).Once()
	553	+	mockBox.EXPECT().InsertChildAfter(mockContainer, mockButton).Once()
	554	+	} else {
	555	+	// Insert at beginning using Prepend
	556	+	mockBox.EXPECT().Prepend(mockContainer).Once()
	557	+	mockBox.EXPECT().Prepend(mockButton).Once()
	558	+	}
	559	+
	560	+	return mockTitleBar, mockContainer
	561	+	}
	562	+
	563	+	func TestInsertPaneAfter_AtBeginning(t *testing.T) {
	564	+	// Arrange
	565	+	ctx := context.Background()
	566	+	mockFactory, mockBox := setupMockFactory(t)
	567	+
	568	+	// First pane - appended normally
	569	+	mockTitleBar1, _, _, _, mockContainer1 := setupPaneMocks(t, mockFactory, mockBox)
	570	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
	571	+	mockContainer1.EXPECT().SetVisible(true).Once()
	572	+	mockTitleBar1.EXPECT().AddCssClass("active").Once()
	573	+
	574	+	sv := layout.NewStackedView(mockFactory)
	575	+	sv.AddPane(ctx, "Page 1", "", mockContainer1)
	576	+
	577	+	// Second pane - inserted at beginning (afterIndex=-1)
	578	+	mockTitleBar2, mockContainer2 := setupInsertPaneMocks(t, mockFactory, mockBox, nil)
	579	+
	580	+	// Visibility updates
	581	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
	582	+	mockContainer1.EXPECT().SetVisible(false).Once()
	583	+	mockTitleBar1.EXPECT().RemoveCssClass("active").Once()
	584	+
	585	+	mockTitleBar2.EXPECT().GetParent().Return(nil).Maybe()
	586	+	mockContainer2.EXPECT().SetVisible(true).Once()
	587	+	mockTitleBar2.EXPECT().AddCssClass("active").Once()
	588	+
	589	+	// Act
	590	+	index := sv.InsertPaneAfter(ctx, -1, "Page 0", "", mockContainer2)
	591	+
	592	+	// Assert
	593	+	assert.Equal(t, 0, index)
	594	+	assert.Equal(t, 2, sv.Count())
	595	+	assert.Equal(t, 0, sv.ActiveIndex())
	596	+	}
	597	+
	598	+	func TestInsertPaneAfter_InMiddle(t *testing.T) {
	599	+	// Arrange
	600	+	ctx := context.Background()
	601	+	mockFactory, mockBox := setupMockFactory(t)
	602	+
	603	+	// Setup 2 initial panes
	604	+	containers := make([]*mocks.MockWidget, 2)
	605	+	titleBars := make([]*mocks.MockBoxWidget, 2)
	606	+
	607	+	for i := 0; i < 2; i++ {
	608	+	titleBars[i], _, _, _, containers[i] = setupPaneMocks(t, mockFactory, mockBox)
	609	+	titleBars[i].EXPECT().GetParent().Return(nil).Maybe()
	610	+	containers[i].EXPECT().SetVisible(mock.Anything).Maybe()
	611	+	titleBars[i].EXPECT().AddCssClass("active").Maybe()
	612	+	titleBars[i].EXPECT().RemoveCssClass("active").Maybe()
	613	+	}
	614	+
	615	+	sv := layout.NewStackedView(mockFactory)
	616	+	sv.AddPane(ctx, "Page 1", "", containers[0])
	617	+	sv.AddPane(ctx, "Page 2", "", containers[1])
	618	+
	619	+	// Set active to first pane
	620	+	require.NoError(t, sv.SetActive(ctx, 0))
	621	+
	622	+	// Insert new pane after index 0 (should become index 1)
	623	+	mockTitleBar3, mockContainer3 := setupInsertPaneMocks(t, mockFactory, mockBox, containers[0])
	624	+	mockTitleBar3.EXPECT().GetParent().Return(nil).Maybe()
	625	+	mockContainer3.EXPECT().SetVisible(mock.Anything).Maybe()
	626	+	mockTitleBar3.EXPECT().AddCssClass("active").Maybe()
	627	+	mockTitleBar3.EXPECT().RemoveCssClass("active").Maybe()
	628	+
	629	+	// Act
	630	+	index := sv.InsertPaneAfter(ctx, 0, "Page 1.5", "", mockContainer3)
	631	+
	632	+	// Assert
	633	+	assert.Equal(t, 1, index)
	634	+	assert.Equal(t, 3, sv.Count())
	635	+	assert.Equal(t, 1, sv.ActiveIndex()) // New pane becomes active
	636	+	}
	637	+
	638	+	func TestInsertPaneAfter_AtEnd(t *testing.T) {
	639	+	// Arrange
	640	+	ctx := context.Background()
	641	+	mockFactory, mockBox := setupMockFactory(t)
	642	+
	643	+	// First pane
	644	+	mockTitleBar1, _, _, _, mockContainer1 := setupPaneMocks(t, mockFactory, mockBox)
	645	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
	646	+	mockContainer1.EXPECT().SetVisible(true).Once()
	647	+	mockTitleBar1.EXPECT().AddCssClass("active").Once()
	648	+
	649	+	sv := layout.NewStackedView(mockFactory)
	650	+	sv.AddPane(ctx, "Page 1", "", mockContainer1)
	651	+
	652	+	// Insert after last pane (afterIndex=0, becomes index 1)
	653	+	mockTitleBar2, mockContainer2 := setupInsertPaneMocks(t, mockFactory, mockBox, mockContainer1)
	654	+
	655	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
	656	+	mockContainer1.EXPECT().SetVisible(false).Once()
	657	+	mockTitleBar1.EXPECT().RemoveCssClass("active").Once()
	658	+
	659	+	mockTitleBar2.EXPECT().GetParent().Return(nil).Maybe()
	660	+	mockContainer2.EXPECT().SetVisible(true).Once()
	661	+	mockTitleBar2.EXPECT().AddCssClass("active").Once()
	662	+
	663	+	// Act
	664	+	index := sv.InsertPaneAfter(ctx, 0, "Page 2", "", mockContainer2)
	665	+
	666	+	// Assert
	667	+	assert.Equal(t, 1, index)
	668	+	assert.Equal(t, 2, sv.Count())
	669	+	assert.Equal(t, 1, sv.ActiveIndex())
	670	+	}
	671	+
	672	+	func TestInsertPaneAfter_MaintainsOrder(t *testing.T) {
	673	+	// Arrange
	674	+	ctx := context.Background()
	675	+	mockFactory, mockBox := setupMockFactory(t)
	676	+
	677	+	// Setup 3 initial panes: A, B, C
	678	+	containers := make([]*mocks.MockWidget, 3)
	679	+	titleBars := make([]*mocks.MockBoxWidget, 3)
	680	+
	681	+	for i := 0; i < 3; i++ {
	682	+	titleBars[i], _, _, _, containers[i] = setupPaneMocks(t, mockFactory, mockBox)
	683	+	titleBars[i].EXPECT().GetParent().Return(nil).Maybe()
	684	+	containers[i].EXPECT().SetVisible(mock.Anything).Maybe()
	685	+	titleBars[i].EXPECT().AddCssClass("active").Maybe()
	686	+	titleBars[i].EXPECT().RemoveCssClass("active").Maybe()
	687	+	}
	688	+
	689	+	sv := layout.NewStackedView(mockFactory)
	690	+	sv.AddPane(ctx, "A", "", containers[0]) // index 0
	691	+	sv.AddPane(ctx, "B", "", containers[1]) // index 1
	692	+	sv.AddPane(ctx, "C", "", containers[2]) // index 2
	693	+
	694	+	// Navigate to pane B (index 1)
	695	+	require.NoError(t, sv.SetActive(ctx, 1))
	696	+
	697	+	// Insert D after B (should be at index 2, C moves to index 3)
	698	+	mockTitleBar4, mockContainer4 := setupInsertPaneMocks(t, mockFactory, mockBox, containers[1])
	699	+	mockTitleBar4.EXPECT().GetParent().Return(nil).Maybe()
	700	+	mockContainer4.EXPECT().SetVisible(mock.Anything).Maybe()
	701	+	mockTitleBar4.EXPECT().AddCssClass("active").Maybe()
	702	+	mockTitleBar4.EXPECT().RemoveCssClass("active").Maybe()
	703	+
	704	+	// Act
	705	+	index := sv.InsertPaneAfter(ctx, 1, "D", "", mockContainer4)
	706	+
	707	+	// Assert: Order should be A(0), B(1), D(2), C(3)
	708	+	assert.Equal(t, 2, index)
	709	+	assert.Equal(t, 4, sv.Count())
	710	+	assert.Equal(t, 2, sv.ActiveIndex()) // D is now active
	711	+
	712	+	// Verify we can still get containers at expected indices
	713	+	containerA, _ := sv.GetContainer(0)
	714	+	containerB, _ := sv.GetContainer(1)
	715	+	containerD, _ := sv.GetContainer(2)
	716	+	containerC, _ := sv.GetContainer(3)
	717	+
	718	+	assert.Equal(t, containers[0], containerA)
	719	+	assert.Equal(t, containers[1], containerB)
	720	+	assert.Equal(t, mockContainer4, containerD)
	721	+	assert.Equal(t, containers[2], containerC)
	722	+	}
	723	+
	724	+	func TestInsertPaneAfter_InvalidIndexClamped(t *testing.T) {
	725	+	// Arrange
	726	+	ctx := context.Background()
	727	+	mockFactory, mockBox := setupMockFactory(t)
	728	+
	729	+	// First pane
	730	+	mockTitleBar1, _, _, _, mockContainer1 := setupPaneMocks(t, mockFactory, mockBox)
	731	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
	732	+	mockContainer1.EXPECT().SetVisible(true).Once()
	733	+	mockTitleBar1.EXPECT().AddCssClass("active").Once()
	734	+
	735	+	sv := layout.NewStackedView(mockFactory)
	736	+	sv.AddPane(ctx, "Page 1", "", mockContainer1)
	737	+
	738	+	// Try to insert at invalid index (100) - should clamp to end
	739	+	mockTitleBar2, mockContainer2 := setupInsertPaneMocks(t, mockFactory, mockBox, mockContainer1)
	740	+
	741	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
	742	+	mockContainer1.EXPECT().SetVisible(false).Once()
	743	+	mockTitleBar1.EXPECT().RemoveCssClass("active").Once()
	744	+
	745	+	mockTitleBar2.EXPECT().GetParent().Return(nil).Maybe()
	746	+	mockContainer2.EXPECT().SetVisible(true).Once()
	747	+	mockTitleBar2.EXPECT().AddCssClass("active").Once()
	748	+
	749	+	// Act - afterIndex=100 should be clamped to 0 (last valid index)
	750	+	index := sv.InsertPaneAfter(ctx, 100, "Page 2", "", mockContainer2)
	751	+
	752	+	// Assert
	753	+	assert.Equal(t, 1, index)
	754	+	assert.Equal(t, 2, sv.Count())
	755	+	}


@@ -504,3 +504,252 @@ func TestSetOnActivate_Callback(t *testing.T) {
504	// simulating a button click. The test verifies the method doesn't panic.	504		// simulating a button click. The test verifies the method doesn't panic.
505	// Integration tests would verify the actual callback invocation.	505		// Integration tests would verify the actual callback invocation.
506	}	506		}
		507	+
		508	+	// setupInsertPaneMocks creates mocks needed for InsertPaneAfter with position-aware insertion.
		509	+	// Returns only the titleBar and container mocks that are needed by test assertions.
		510	+	func setupInsertPaneMocks(
		511	+	t *testing.T,
		512	+	mockFactory *mocks.MockWidgetFactory,
		513	+	mockBox *mocks.MockBoxWidget,
		514	+	siblingContainer layout.Widget,
		515	+	) (mocks.MockBoxWidget, mocks.MockWidget) {
		516	+	mockTitleBar := mocks.NewMockBoxWidget(t)
		517	+	mockFavicon := mocks.NewMockImageWidget(t)
		518	+	mockLabel := mocks.NewMockLabelWidget(t)
		519	+	mockButton := mocks.NewMockButtonWidget(t)
		520	+	mockContainer := mocks.NewMockWidget(t)
		521	+
		522	+	// Title bar creation
		523	+	mockFactory.EXPECT().NewBox(layout.OrientationHorizontal, 4).Return(mockTitleBar).Once()
		524	+	mockTitleBar.EXPECT().AddCssClass("stacked-pane-titlebar").Once()
		525	+	mockTitleBar.EXPECT().SetVexpand(false).Once()
		526	+
		527	+	// Favicon
		528	+	mockFactory.EXPECT().NewImage().Return(mockFavicon).Once()
		529	+	mockFavicon.EXPECT().SetFromIconName(mock.Anything).Once()
		530	+	mockFavicon.EXPECT().SetPixelSize(16).Once()
		531	+	mockTitleBar.EXPECT().Append(mockFavicon).Once()
		532	+
		533	+	// Label
		534	+	mockFactory.EXPECT().NewLabel(mock.Anything).Return(mockLabel).Once()
		535	+	mockLabel.EXPECT().SetEllipsize(layout.EllipsizeEnd).Once()
		536	+	mockLabel.EXPECT().SetMaxWidthChars(30).Once()
		537	+	mockLabel.EXPECT().SetHexpand(true).Once()
		538	+	mockLabel.EXPECT().SetXalign(float32(0.0)).Once()
		539	+	mockTitleBar.EXPECT().Append(mockLabel).Once()
		540	+
		541	+	// Button wrapping title bar
		542	+	mockFactory.EXPECT().NewButton().Return(mockButton).Once()
		543	+	mockButton.EXPECT().SetChild(mockTitleBar).Once()
		544	+	mockButton.EXPECT().AddCssClass("stacked-pane-title-button").Once()
		545	+	mockButton.EXPECT().SetFocusOnClick(false).Once()
		546	+	mockButton.EXPECT().SetVexpand(false).Once()
		547	+	mockButton.EXPECT().SetHexpand(true).Once()
		548	+	mockButton.EXPECT().ConnectClicked(mock.Anything).Return(uint32(1)).Once()
		549	+
		550	+	// Position-aware insertion using InsertChildAfter
		551	+	if siblingContainer != nil {
		552	+	mockBox.EXPECT().InsertChildAfter(mockButton, siblingContainer).Once()
		553	+	mockBox.EXPECT().InsertChildAfter(mockContainer, mockButton).Once()
		554	+	} else {
		555	+	// Insert at beginning using Prepend
		556	+	mockBox.EXPECT().Prepend(mockContainer).Once()
		557	+	mockBox.EXPECT().Prepend(mockButton).Once()
		558	+	}
		559	+
		560	+	return mockTitleBar, mockContainer
		561	+	}
		562	+
		563	+	func TestInsertPaneAfter_AtBeginning(t *testing.T) {
		564	+	// Arrange
		565	+	ctx := context.Background()
		566	+	mockFactory, mockBox := setupMockFactory(t)
		567	+
		568	+	// First pane - appended normally
		569	+	mockTitleBar1, _, _, _, mockContainer1 := setupPaneMocks(t, mockFactory, mockBox)
		570	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
		571	+	mockContainer1.EXPECT().SetVisible(true).Once()
		572	+	mockTitleBar1.EXPECT().AddCssClass("active").Once()
		573	+
		574	+	sv := layout.NewStackedView(mockFactory)
		575	+	sv.AddPane(ctx, "Page 1", "", mockContainer1)
		576	+
		577	+	// Second pane - inserted at beginning (afterIndex=-1)
		578	+	mockTitleBar2, mockContainer2 := setupInsertPaneMocks(t, mockFactory, mockBox, nil)
		579	+
		580	+	// Visibility updates
		581	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
		582	+	mockContainer1.EXPECT().SetVisible(false).Once()
		583	+	mockTitleBar1.EXPECT().RemoveCssClass("active").Once()
		584	+
		585	+	mockTitleBar2.EXPECT().GetParent().Return(nil).Maybe()
		586	+	mockContainer2.EXPECT().SetVisible(true).Once()
		587	+	mockTitleBar2.EXPECT().AddCssClass("active").Once()
		588	+
		589	+	// Act
		590	+	index := sv.InsertPaneAfter(ctx, -1, "Page 0", "", mockContainer2)
		591	+
		592	+	// Assert
		593	+	assert.Equal(t, 0, index)
		594	+	assert.Equal(t, 2, sv.Count())
		595	+	assert.Equal(t, 0, sv.ActiveIndex())
		596	+	}
		597	+
		598	+	func TestInsertPaneAfter_InMiddle(t *testing.T) {
		599	+	// Arrange
		600	+	ctx := context.Background()
		601	+	mockFactory, mockBox := setupMockFactory(t)
		602	+
		603	+	// Setup 2 initial panes
		604	+	containers := make([]*mocks.MockWidget, 2)
		605	+	titleBars := make([]*mocks.MockBoxWidget, 2)
		606	+
		607	+	for i := 0; i < 2; i++ {
		608	+	titleBars[i], _, _, _, containers[i] = setupPaneMocks(t, mockFactory, mockBox)
		609	+	titleBars[i].EXPECT().GetParent().Return(nil).Maybe()
		610	+	containers[i].EXPECT().SetVisible(mock.Anything).Maybe()
		611	+	titleBars[i].EXPECT().AddCssClass("active").Maybe()
		612	+	titleBars[i].EXPECT().RemoveCssClass("active").Maybe()
		613	+	}
		614	+
		615	+	sv := layout.NewStackedView(mockFactory)
		616	+	sv.AddPane(ctx, "Page 1", "", containers[0])
		617	+	sv.AddPane(ctx, "Page 2", "", containers[1])
		618	+
		619	+	// Set active to first pane
		620	+	require.NoError(t, sv.SetActive(ctx, 0))
		621	+
		622	+	// Insert new pane after index 0 (should become index 1)
		623	+	mockTitleBar3, mockContainer3 := setupInsertPaneMocks(t, mockFactory, mockBox, containers[0])
		624	+	mockTitleBar3.EXPECT().GetParent().Return(nil).Maybe()
		625	+	mockContainer3.EXPECT().SetVisible(mock.Anything).Maybe()
		626	+	mockTitleBar3.EXPECT().AddCssClass("active").Maybe()
		627	+	mockTitleBar3.EXPECT().RemoveCssClass("active").Maybe()
		628	+
		629	+	// Act
		630	+	index := sv.InsertPaneAfter(ctx, 0, "Page 1.5", "", mockContainer3)
		631	+
		632	+	// Assert
		633	+	assert.Equal(t, 1, index)
		634	+	assert.Equal(t, 3, sv.Count())
		635	+	assert.Equal(t, 1, sv.ActiveIndex()) // New pane becomes active
		636	+	}
		637	+
		638	+	func TestInsertPaneAfter_AtEnd(t *testing.T) {
		639	+	// Arrange
		640	+	ctx := context.Background()
		641	+	mockFactory, mockBox := setupMockFactory(t)
		642	+
		643	+	// First pane
		644	+	mockTitleBar1, _, _, _, mockContainer1 := setupPaneMocks(t, mockFactory, mockBox)
		645	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
		646	+	mockContainer1.EXPECT().SetVisible(true).Once()
		647	+	mockTitleBar1.EXPECT().AddCssClass("active").Once()
		648	+
		649	+	sv := layout.NewStackedView(mockFactory)
		650	+	sv.AddPane(ctx, "Page 1", "", mockContainer1)
		651	+
		652	+	// Insert after last pane (afterIndex=0, becomes index 1)
		653	+	mockTitleBar2, mockContainer2 := setupInsertPaneMocks(t, mockFactory, mockBox, mockContainer1)
		654	+
		655	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
		656	+	mockContainer1.EXPECT().SetVisible(false).Once()
		657	+	mockTitleBar1.EXPECT().RemoveCssClass("active").Once()
		658	+
		659	+	mockTitleBar2.EXPECT().GetParent().Return(nil).Maybe()
		660	+	mockContainer2.EXPECT().SetVisible(true).Once()
		661	+	mockTitleBar2.EXPECT().AddCssClass("active").Once()
		662	+
		663	+	// Act
		664	+	index := sv.InsertPaneAfter(ctx, 0, "Page 2", "", mockContainer2)
		665	+
		666	+	// Assert
		667	+	assert.Equal(t, 1, index)
		668	+	assert.Equal(t, 2, sv.Count())
		669	+	assert.Equal(t, 1, sv.ActiveIndex())
		670	+	}
		671	+
		672	+	func TestInsertPaneAfter_MaintainsOrder(t *testing.T) {
		673	+	// Arrange
		674	+	ctx := context.Background()
		675	+	mockFactory, mockBox := setupMockFactory(t)
		676	+
		677	+	// Setup 3 initial panes: A, B, C
		678	+	containers := make([]*mocks.MockWidget, 3)
		679	+	titleBars := make([]*mocks.MockBoxWidget, 3)
		680	+
		681	+	for i := 0; i < 3; i++ {
		682	+	titleBars[i], _, _, _, containers[i] = setupPaneMocks(t, mockFactory, mockBox)
		683	+	titleBars[i].EXPECT().GetParent().Return(nil).Maybe()
		684	+	containers[i].EXPECT().SetVisible(mock.Anything).Maybe()
		685	+	titleBars[i].EXPECT().AddCssClass("active").Maybe()
		686	+	titleBars[i].EXPECT().RemoveCssClass("active").Maybe()
		687	+	}
		688	+
		689	+	sv := layout.NewStackedView(mockFactory)
		690	+	sv.AddPane(ctx, "A", "", containers[0]) // index 0
		691	+	sv.AddPane(ctx, "B", "", containers[1]) // index 1
		692	+	sv.AddPane(ctx, "C", "", containers[2]) // index 2
		693	+
		694	+	// Navigate to pane B (index 1)
		695	+	require.NoError(t, sv.SetActive(ctx, 1))
		696	+
		697	+	// Insert D after B (should be at index 2, C moves to index 3)
		698	+	mockTitleBar4, mockContainer4 := setupInsertPaneMocks(t, mockFactory, mockBox, containers[1])
		699	+	mockTitleBar4.EXPECT().GetParent().Return(nil).Maybe()
		700	+	mockContainer4.EXPECT().SetVisible(mock.Anything).Maybe()
		701	+	mockTitleBar4.EXPECT().AddCssClass("active").Maybe()
		702	+	mockTitleBar4.EXPECT().RemoveCssClass("active").Maybe()
		703	+
		704	+	// Act
		705	+	index := sv.InsertPaneAfter(ctx, 1, "D", "", mockContainer4)
		706	+
		707	+	// Assert: Order should be A(0), B(1), D(2), C(3)
		708	+	assert.Equal(t, 2, index)
		709	+	assert.Equal(t, 4, sv.Count())
		710	+	assert.Equal(t, 2, sv.ActiveIndex()) // D is now active
		711	+
		712	+	// Verify we can still get containers at expected indices
		713	+	containerA, _ := sv.GetContainer(0)
		714	+	containerB, _ := sv.GetContainer(1)
		715	+	containerD, _ := sv.GetContainer(2)
		716	+	containerC, _ := sv.GetContainer(3)
		717	+
		718	+	assert.Equal(t, containers[0], containerA)
		719	+	assert.Equal(t, containers[1], containerB)
		720	+	assert.Equal(t, mockContainer4, containerD)
		721	+	assert.Equal(t, containers[2], containerC)
		722	+	}
		723	+
		724	+	func TestInsertPaneAfter_InvalidIndexClamped(t *testing.T) {
		725	+	// Arrange
		726	+	ctx := context.Background()
		727	+	mockFactory, mockBox := setupMockFactory(t)
		728	+
		729	+	// First pane
		730	+	mockTitleBar1, _, _, _, mockContainer1 := setupPaneMocks(t, mockFactory, mockBox)
		731	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
		732	+	mockContainer1.EXPECT().SetVisible(true).Once()
		733	+	mockTitleBar1.EXPECT().AddCssClass("active").Once()
		734	+
		735	+	sv := layout.NewStackedView(mockFactory)
		736	+	sv.AddPane(ctx, "Page 1", "", mockContainer1)
		737	+
		738	+	// Try to insert at invalid index (100) - should clamp to end
		739	+	mockTitleBar2, mockContainer2 := setupInsertPaneMocks(t, mockFactory, mockBox, mockContainer1)
		740	+
		741	+	mockTitleBar1.EXPECT().GetParent().Return(nil).Maybe()
		742	+	mockContainer1.EXPECT().SetVisible(false).Once()
		743	+	mockTitleBar1.EXPECT().RemoveCssClass("active").Once()
		744	+
		745	+	mockTitleBar2.EXPECT().GetParent().Return(nil).Maybe()
		746	+	mockContainer2.EXPECT().SetVisible(true).Once()
		747	+	mockTitleBar2.EXPECT().AddCssClass("active").Once()
		748	+
		749	+	// Act - afterIndex=100 should be clamped to 0 (last valid index)
		750	+	index := sv.InsertPaneAfter(ctx, 100, "Page 2", "", mockContainer2)
		751	+
		752	+	// Assert
		753	+	assert.Equal(t, 1, index)
		754	+	assert.Equal(t, 2, sv.Count())
		755	+	}