Fix rq0 detail identity by UUID

6 files changed, 173 insertions, 28 deletions

diff --git a/internal/ui/detail_handlers.go b/internal/ui/detail_handlers.go
index a53749d..d61f29d 100644
--- a/internal/ui/detail_handlers.go
+++ b/internal/ui/detail_handlers.go
@@ -145,7 +145,7 @@ func (m *Model) handleDetailUndo() (tea.Model, tea.Cmd) {
 // done, undo).
 func (m *Model) closeDetailView() {
 	m.showTaskDetail = false
-	m.currentTaskDetailID = 0
+	m.clearCurrentTaskDetail()
 	m.detailSearching = false
 	m.detailSearchRegex = nil
 	m.detailSearchInput.SetValue("")
diff --git a/internal/ui/keyactions.go b/internal/ui/keyactions.go
index 9c80585..57a9c2e 100644
--- a/internal/ui/keyactions.go
+++ b/internal/ui/keyactions.go
@@ -689,9 +689,9 @@ func (m *Model) handleShowTaskDetail() (tea.Model, tea.Cmd) {
 		return m, nil
 	}
 
-	if m.taskByID(id) != nil {
+	if t := m.taskByID(id); t != nil {
 		m.showTaskDetail = true
-		m.currentTaskDetailID = id
+		m.setCurrentTaskDetail(t)
 		m.detailSearching = false
 		m.detailSearchRegex = nil
 		m.detailFieldIndex = 0
diff --git a/internal/ui/keyhandlers.go b/internal/ui/keyhandlers.go
index 116f850..690db05 100644
--- a/internal/ui/keyhandlers.go
+++ b/internal/ui/keyhandlers.go
@@ -274,7 +274,7 @@ func (m *Model) handleQuitKey() (tea.Model, tea.Cmd) {
 	}
 	if m.showTaskDetail {
 		m.showTaskDetail = false
-		m.currentTaskDetailID = 0
+		m.clearCurrentTaskDetail()
 		m.detailSearching = false
 		m.detailSearchRegex = nil
 		m.detailSearchInput.SetValue("")
@@ -313,7 +313,7 @@ func (m *Model) handleEscapeKey() (tea.Model, tea.Cmd) {
 	}
 	if m.showTaskDetail {
 		m.showTaskDetail = false
-		m.currentTaskDetailID = 0
+		m.clearCurrentTaskDetail()
 		m.detailSearching = false
 		m.detailSearchRegex = nil
 		m.detailSearchInput.SetValue("")
diff --git a/internal/ui/table.go b/internal/ui/table.go
index 69e8dff..29ec388 100644
--- a/internal/ui/table.go
+++ b/internal/ui/table.go
@@ -82,15 +82,16 @@ type searchState struct {
 // Blink fields here are separate from blinkState because they drive a
 // per-field highlight inside the detail view rather than a table row.
 type detailViewState struct {
-	showTaskDetail      bool
-	currentTaskDetailID int
-	detailSearching     bool
-	detailSearchInput   textinput.Model
-	detailSearchRegex   *regexp.Regexp
-	detailFieldIndex    int  // currently selected field (-1 = none)
-	detailBlinkField    int  // field currently blinking (-1 = none)
-	detailBlinkOn       bool // whether the blink is currently on
-	detailBlinkCount    int  // number of blink cycles completed so far
+	showTaskDetail              bool
+	currentTaskDetailUUID       string
+	currentTaskDetailFallbackID int
+	detailSearching             bool
+	detailSearchInput           textinput.Model
+	detailSearchRegex           *regexp.Regexp
+	detailFieldIndex            int  // currently selected field (-1 = none)
+	detailBlinkField            int  // field currently blinking (-1 = none)
+	detailBlinkOn               bool // whether the blink is currently on
+	detailBlinkCount            int  // number of blink cycles completed so far
 }
 
 // ultraState holds the state for the ultra mode task list and its search UI.
diff --git a/internal/ui/table_test.go b/internal/ui/table_test.go
index e30e6d7..74a5f57 100644
--- a/internal/ui/table_test.go
+++ b/internal/ui/table_test.go
@@ -209,7 +209,7 @@ func TestNewWithTaskwarriorRejectsNilClient(t *testing.T) {
 	}
 }
 
-func TestHandleShowTaskDetailTracksTaskID(t *testing.T) {
+func TestHandleShowTaskDetailTracksTaskUUID(t *testing.T) {
 	fake := &fakeTaskwarrior{
 		tasks: []task.Task{
 			{ID: 1, UUID: "fake-1", Description: "original detail", Status: "pending"},
@@ -226,14 +226,42 @@ func TestHandleShowTaskDetailTracksTaskID(t *testing.T) {
 	if !m.showTaskDetail {
 		t.Fatalf("detail view was not shown")
 	}
-	if m.currentTaskDetailID != 1 {
-		t.Fatalf("current detail task ID = %d, want 1", m.currentTaskDetailID)
+	if m.currentTaskDetailUUID != "fake-1" {
+		t.Fatalf("current detail task UUID = %q, want fake-1", m.currentTaskDetailUUID)
+	}
+	if m.currentTaskDetailFallbackID != 0 {
+		t.Fatalf("current detail fallback ID = %d, want 0", m.currentTaskDetailFallbackID)
 	}
 	if got := m.renderTaskDetail(); !strings.Contains(got, "original detail") {
 		t.Fatalf("rendered detail %q does not include original task description", got)
 	}
 }
 
+func TestHandleShowTaskDetailFallsBackToTaskIDWhenUUIDMissing(t *testing.T) {
+	fake := &fakeTaskwarrior{
+		tasks: []task.Task{
+			{ID: 1, Description: "legacy detail", Status: "pending"},
+		},
+	}
+	m, err := NewWithTaskwarrior(nil, "firefox", fake)
+	if err != nil {
+		t.Fatalf("NewWithTaskwarrior: %v", err)
+	}
+
+	mv, _ := (&m).handleShowTaskDetail()
+	m = *mv.(*Model)
+
+	if m.currentTaskDetailUUID != "" {
+		t.Fatalf("current detail task UUID = %q, want empty fallback", m.currentTaskDetailUUID)
+	}
+	if m.currentTaskDetailFallbackID != 1 {
+		t.Fatalf("current detail fallback ID = %d, want 1", m.currentTaskDetailFallbackID)
+	}
+	if got := m.renderTaskDetail(); !strings.Contains(got, "legacy detail") {
+		t.Fatalf("rendered detail %q does not include legacy task description", got)
+	}
+}
+
 func TestTaskDetailUsesReplacedTaskSlice(t *testing.T) {
 	fake := &fakeTaskwarrior{
 		tasks: []task.Task{
@@ -260,11 +288,82 @@ func TestTaskDetailUsesReplacedTaskSlice(t *testing.T) {
 	}
 }
 
+func TestTaskDetailRejectsSameNumericIDDifferentUUIDAfterReload(t *testing.T) {
+	fake := &fakeTaskwarrior{
+		tasks: []task.Task{
+			{ID: 1, UUID: "fake-1", Description: "original detail", Status: "pending"},
+		},
+	}
+	m, err := NewWithTaskwarrior(nil, "firefox", fake)
+	if err != nil {
+		t.Fatalf("NewWithTaskwarrior: %v", err)
+	}
+
+	mv, _ := (&m).handleShowTaskDetail()
+	m = *mv.(*Model)
+	m.tasks = []task.Task{
+		{ID: 1, UUID: "fake-2", Description: "wrong detail", Status: "pending"},
+	}
+
+	m.refreshCurrentTaskDetail()
+
+	if m.showTaskDetail {
+		t.Fatalf("detail view stayed open for different UUID with same numeric ID")
+	}
+	if m.currentTaskDetailUUID != "" {
+		t.Fatalf("current detail task UUID = %q, want cleared", m.currentTaskDetailUUID)
+	}
+	if m.currentTaskDetailFallbackID != 0 {
+		t.Fatalf("current detail fallback ID = %d, want 0", m.currentTaskDetailFallbackID)
+	}
+	if got := m.renderTaskDetail(); got != "No task selected" {
+		t.Fatalf("rendered detail = %q, want no task selected", got)
+	}
+}
+
+func TestTaskDetailUsesSameUUIDAfterNumericIDChanges(t *testing.T) {
+	fake := &fakeTaskwarrior{
+		tasks: []task.Task{
+			{ID: 1, UUID: "fake-1", Description: "old detail", Status: "pending"},
+		},
+	}
+	m, err := NewWithTaskwarrior(nil, "firefox", fake)
+	if err != nil {
+		t.Fatalf("NewWithTaskwarrior: %v", err)
+	}
+
+	mv, _ := (&m).handleShowTaskDetail()
+	m = *mv.(*Model)
+	m.tasks = []task.Task{
+		{ID: 7, UUID: "fake-1", Description: "renumbered detail", Status: "pending"},
+	}
+
+	m.refreshCurrentTaskDetail()
+
+	if !m.showTaskDetail {
+		t.Fatalf("detail view closed for same UUID with new numeric ID")
+	}
+	current := m.currentDetailTask()
+	if current == nil {
+		t.Fatalf("current detail task was nil")
+	}
+	if current.ID != 7 {
+		t.Fatalf("current detail task ID = %d, want 7", current.ID)
+	}
+	got := m.renderTaskDetail()
+	if !strings.Contains(got, "renumbered detail") {
+		t.Fatalf("rendered detail %q does not include renumbered task description", got)
+	}
+	if strings.Contains(got, "old detail") {
+		t.Fatalf("rendered detail %q still includes stale task description", got)
+	}
+}
+
 func TestRefreshCurrentTaskDetailClosesMissingTask(t *testing.T) {
 	m := Model{
 		detailViewState: detailViewState{
-			showTaskDetail:      true,
-			currentTaskDetailID: 1,
+			showTaskDetail:        true,
+			currentTaskDetailUUID: "fake-1",
 		},
 		tasks: []task.Task{
 			{ID: 2, UUID: "fake-2", Description: "different task", Status: "pending"},
@@ -276,8 +375,11 @@ func TestRefreshCurrentTaskDetailClosesMissingTask(t *testing.T) {
 	if m.showTaskDetail {
 		t.Fatalf("detail view stayed open for missing task")
 	}
-	if m.currentTaskDetailID != 0 {
-		t.Fatalf("current detail task ID = %d, want 0", m.currentTaskDetailID)
+	if m.currentTaskDetailUUID != "" {
+		t.Fatalf("current detail task UUID = %q, want cleared", m.currentTaskDetailUUID)
+	}
+	if m.currentTaskDetailFallbackID != 0 {
+		t.Fatalf("current detail fallback ID = %d, want 0", m.currentTaskDetailFallbackID)
 	}
 	if got := m.renderTaskDetail(); got != "No task selected" {
 		t.Fatalf("rendered detail = %q, want no task selected", got)
@@ -518,8 +620,8 @@ func TestHandleDescEditDoneUpdatesDescriptionAndRemovesTempFile(t *testing.T) {
 	if err != nil {
 		t.Fatalf("New: %v", err)
 	}
-	m.currentTaskDetailID = 1
 	m.showTaskDetail = true
+	m.currentTaskDetailUUID = "x"
 	m.detailDescEditing = true
 
 	tempFile := filepath.Join(tmp, "desc.txt")
@@ -1385,7 +1487,7 @@ func TestHandleRecurrenceModeDetailBlinkTargetsRecurField(t *testing.T) {
 	m := newRecurrenceDetailModel(t, "")
 
 	m.showTaskDetail = true
-	m.currentTaskDetailID = m.tasks[0].ID
+	m.setCurrentTaskDetail(&m.tasks[0])
 	current := m.currentDetailTask()
 	m.activateRecurEdit(current.ID, current.Recur)
 	m.recurInput.SetValue("daily")
@@ -1418,7 +1520,7 @@ func TestHandleRecurrenceModeDetailFallsBackWhenRecurrenceRemoved(t *testing.T)
 	m := newRecurrenceDetailModel(t, "daily")
 
 	m.showTaskDetail = true
-	m.currentTaskDetailID = m.tasks[0].ID
+	m.setCurrentTaskDetail(&m.tasks[0])
 	m.detailBlinkField = -1
 	current := m.currentDetailTask()
 	m.activateRecurEdit(current.ID, current.Recur)
diff --git a/internal/ui/taskdetail.go b/internal/ui/taskdetail.go
index b39af51..bcaed8f 100644
--- a/internal/ui/taskdetail.go
+++ b/internal/ui/taskdetail.go
@@ -369,16 +369,58 @@ func (m *Model) taskByID(id int) *task.Task {
 	return nil
 }
 
+func (m *Model) taskByUUID(uuid string) *task.Task {
+	uuid = strings.TrimSpace(uuid)
+	if uuid == "" {
+		return nil
+	}
+	for i := range m.tasks {
+		if m.tasks[i].UUID == uuid {
+			return &m.tasks[i]
+		}
+	}
+	return nil
+}
+
 func (m *Model) currentDetailTask() *task.Task {
-	if !m.showTaskDetail || m.currentTaskDetailID == 0 {
+	if !m.showTaskDetail {
 		return nil
 	}
-	return m.taskByID(m.currentTaskDetailID)
+	if m.currentTaskDetailUUID != "" {
+		return m.taskByUUID(m.currentTaskDetailUUID)
+	}
+	if m.currentTaskDetailFallbackID != 0 {
+		return m.taskByID(m.currentTaskDetailFallbackID)
+	}
+	return nil
+}
+
+func (m *Model) setCurrentTaskDetail(t *task.Task) {
+	// UUID is stable across Taskwarrior renumbering. Numeric ID is used only
+	// for legacy/defensive compatibility when a task has no UUID.
+	m.currentTaskDetailUUID = strings.TrimSpace(t.UUID)
+	if m.currentTaskDetailUUID != "" {
+		m.currentTaskDetailFallbackID = 0
+		return
+	}
+	m.currentTaskDetailFallbackID = t.ID
+}
+
+func (m *Model) clearCurrentTaskDetail() {
+	m.currentTaskDetailUUID = ""
+	m.currentTaskDetailFallbackID = 0
+}
+
+func (m *Model) hasCurrentTaskDetailIdentity() bool {
+	if m.currentTaskDetailUUID != "" {
+		return true
+	}
+	return m.currentTaskDetailFallbackID != 0
 }
 
 // refreshCurrentTaskDetail validates detail state after a reload.
 func (m *Model) refreshCurrentTaskDetail() {
-	if m.currentTaskDetailID == 0 {
+	if !m.hasCurrentTaskDetailIdentity() {
 		return
 	}
 	if m.currentDetailTask() != nil {
@@ -387,7 +429,7 @@ func (m *Model) refreshCurrentTaskDetail() {
 
 	// Task no longer exists, clear detail view
 	m.showTaskDetail = false
-	m.currentTaskDetailID = 0
+	m.clearCurrentTaskDetail()
 }
 
 // detailDescriptionFieldIndex returns the navigable field index for the