Simplify focus navigation behavior

Remove remembered right-column focus so split-mode entry into the right column is deterministic, keep the simpler procedural grid-walking flow, and add regression coverage for the focus navigation cases.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: johannesjo

src/store/core.ts

@@ -68,17 +68,11 @@ export const [store, setStore] = createStore<AppStore>({
   keybindingMigrationDismissed: false,
   focusMode: false,
   taskSplitMode: {},
-  lastRightColFocus: {},
 });
 
 type CleanupPanelStore = Pick<
   AppStore,
-  | 'focusedPanel'
-  | 'panelSizes'
-  | 'taskOrder'
-  | 'collapsedTaskOrder'
-  | 'taskSplitMode'
-  | 'lastRightColFocus'
+  'focusedPanel' | 'panelSizes' | 'taskOrder' | 'collapsedTaskOrder' | 'taskSplitMode'
 >;
 
 /** Remove panelSizes, focusedPanel, and taskOrder entries for a given ID.
@@ -87,7 +81,6 @@ export function cleanupPanelEntries(s: CleanupPanelStore, id: string): number {
   const idx = s.taskOrder.indexOf(id);
   delete s.focusedPanel[id];
   delete s.taskSplitMode[id];
-  delete s.lastRightColFocus[id];
   const prefix = id + ':';
   for (const key of Object.keys(s.panelSizes)) {
     if (key === id || key.startsWith(prefix)) delete s.panelSizes[key];

src/store/focus.test.ts

@@ -0,0 +1,209 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+
+type MockStore = {
+  activeTaskId: string | null;
+  activeAgentId: string | null;
+  tasks: Record<string, MockTask>;
+  terminals: Record<string, Record<string, unknown>>;
+  taskOrder: string[];
+  projects: Array<{ id: string; terminalBookmarks?: Array<{ id: string; command: string }> }>;
+  focusedPanel: Record<string, string>;
+  sidebarFocused: boolean;
+  sidebarFocusedProjectId: string | null;
+  sidebarFocusedTaskId: string | null;
+  placeholderFocused: boolean;
+  placeholderFocusedButton: 'add-task' | 'add-terminal';
+  showNewTaskDialog: boolean;
+  showHelpDialog: boolean;
+  showSettingsDialog: boolean;
+  showPromptInput: boolean;
+  sidebarVisible: boolean;
+  taskSplitMode: Record<string, boolean>;
+};
+
+type MockTask = {
+  id: string;
+  name: string;
+  projectId: string;
+  agentIds: string[];
+  shellAgentIds: string[];
+  stepsEnabled: boolean;
+  stepsContent: Array<{ id: string }>;
+  collapsed?: boolean;
+  [key: string]: unknown;
+};
+
+let mockStore: MockStore;
+
+function setStorePath(...args: unknown[]): void {
+  const value = args[args.length - 1];
+  let target: Record<string, unknown> = mockStore as unknown as Record<string, unknown>;
+  for (let i = 0; i < args.length - 2; i++) {
+    const key = args[i] as string;
+    const next = target[key] as Record<string, unknown> | undefined;
+    if (!next || typeof next !== 'object') {
+      target[key] = {};
+    }
+    target = target[key] as Record<string, unknown>;
+  }
+  target[args[args.length - 2] as string] = value;
+}
+
+vi.mock('solid-js', () => ({
+  batch: (fn: () => void) => fn(),
+}));
+
+vi.mock('./core', () => ({
+  store: new Proxy(
+    {},
+    {
+      get(_target, prop) {
+        return mockStore[prop as keyof MockStore];
+      },
+    },
+  ),
+  setStore: vi.fn((...args: unknown[]) => setStorePath(...args)),
+}));
+
+vi.mock('./navigation', () => ({
+  setActiveTask: vi.fn((id: string) => {
+    mockStore.activeTaskId = id;
+    mockStore.activeAgentId = mockStore.tasks[id]?.agentIds?.[0] ?? null;
+  }),
+}));
+
+vi.mock('./sidebar-order', () => ({
+  computeSidebarTaskOrder: vi.fn(() => mockStore.taskOrder),
+}));
+
+vi.mock('./tasks', () => ({
+  uncollapseTask: vi.fn((id: string) => {
+    if (mockStore.tasks[id]) mockStore.tasks[id].collapsed = false;
+  }),
+}));
+
+import { navigateColumn, navigateRow } from './focus';
+
+function setTask(id: string, overrides: Record<string, unknown> = {}): void {
+  mockStore.tasks[id] = {
+    id,
+    name: id,
+    projectId: 'project-1',
+    agentIds: ['agent-1'],
+    shellAgentIds: [],
+    stepsEnabled: false,
+    stepsContent: [],
+    ...overrides,
+  };
+}
+
+beforeEach(() => {
+  mockStore = {
+    activeTaskId: 'task-1',
+    activeAgentId: 'agent-1',
+    tasks: {},
+    terminals: {},
+    taskOrder: ['task-1'],
+    projects: [{ id: 'project-1', terminalBookmarks: [] }],
+    focusedPanel: {},
+    sidebarFocused: false,
+    sidebarFocusedProjectId: null,
+    sidebarFocusedTaskId: null,
+    placeholderFocused: false,
+    placeholderFocusedButton: 'add-task',
+    showNewTaskDialog: false,
+    showHelpDialog: false,
+    showSettingsDialog: false,
+    showPromptInput: true,
+    sidebarVisible: true,
+    taskSplitMode: {},
+  };
+
+  vi.stubGlobal('requestAnimationFrame', (cb: FrameRequestCallback) => {
+    cb(0);
+    return 0;
+  });
+  vi.stubGlobal('document', { querySelector: () => null });
+  vi.stubGlobal('CSS', { escape: (value: string) => value });
+});
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+});
+
+describe('focus navigation neighbor map', () => {
+  it('moves down through stacked layout using explicit neighbors', () => {
+    setTask('task-1');
+    mockStore.focusedPanel['task-1'] = 'notes';
+
+    navigateRow('down');
+
+    expect(mockStore.focusedPanel['task-1']).toBe('shell-toolbar:0');
+  });
+
+  it('always enters the top-right panel when moving right from ai-terminal in split mode', () => {
+    setTask('task-1', {
+      stepsEnabled: true,
+      stepsContent: [{ id: 'step-1' }],
+    });
+    mockStore.taskSplitMode['task-1'] = true;
+    mockStore.focusedPanel['task-1'] = 'ai-terminal';
+
+    navigateColumn('right');
+
+    expect(mockStore.focusedPanel['task-1']).toBe('changed-files');
+  });
+
+  it('falls into the top-right panel when split-mode ai-terminal has no lower left neighbor', () => {
+    setTask('task-1', {
+      shellAgentIds: ['shell-1'],
+    });
+    mockStore.taskSplitMode['task-1'] = true;
+    mockStore.showPromptInput = false;
+    mockStore.focusedPanel['task-1'] = 'ai-terminal';
+
+    navigateRow('down');
+
+    expect(mockStore.focusedPanel['task-1']).toBe('changed-files');
+  });
+
+  it('falls back from vanished focused panels before navigating', () => {
+    setTask('task-1', {
+      stepsEnabled: false,
+      stepsContent: [],
+    });
+    mockStore.focusedPanel['task-1'] = 'steps';
+
+    navigateRow('down');
+
+    expect(mockStore.focusedPanel['task-1']).toBe('prompt');
+  });
+
+  it('preserves cross-task row alignment when exiting to the right', () => {
+    setTask('task-1');
+    setTask('task-2');
+    mockStore.taskOrder = ['task-1', 'task-2'];
+    mockStore.focusedPanel['task-1'] = 'changed-files';
+
+    navigateColumn('right');
+
+    expect(mockStore.activeTaskId).toBe('task-2');
+    expect(mockStore.focusedPanel['task-2']).toBe('notes');
+  });
+
+  it('clamps split shell-toolbar down-moves to the last available shell', () => {
+    setTask('task-1', {
+      shellAgentIds: ['shell-1'],
+    });
+    mockStore.projects[0].terminalBookmarks = [
+      { id: 'bookmark-1', command: 'npm test' },
+      { id: 'bookmark-2', command: 'npm run lint' },
+    ];
+    mockStore.taskSplitMode['task-1'] = true;
+    mockStore.focusedPanel['task-1'] = 'shell-toolbar:2';
+
+    navigateRow('down');
+
+    expect(mockStore.focusedPanel['task-1']).toBe('shell:0');
+  });
+});

src/store/focus.ts

@@ -32,16 +32,14 @@ export function triggerAction(key: string): void {
   actionRegistry.get(key)?.();
 }
 
-// Grid-based spatial navigation. Two layouts:
+// Grid-based spatial navigation. Two task layouts:
 //  - vertical stack (default): everything in one column
 //  - split (focus mode, panel wide enough): ai-terminal/prompt anchor the left,
 //    changed-files/notes/steps/shell anchor the right, and `ai-terminal` is
-//    repeated down col 0 so ←/→ cross cleanly into the right column.
-// navigateRow skip-repeats past those duplicates; row-aware → uses
-// `lastRightColFocus` so bouncing ←→ over ai-terminal returns to the origin.
+//    repeated down col 0 so left/right crossings into the right column stay
+//    consistent.
 
-/** Cells that belong to the left column in split mode. Anything else is treated
- *  as right-column for `lastRightColFocus` memory and the dead-end fallback. */
+/** Cells that belong to the left column in split mode. */
 const LEFT_COL_PANELS = new Set(['title', 'ai-terminal', 'prompt', 'terminal']);
 
 function buildGrid(panelId: string): string[][] {
@@ -93,12 +91,8 @@ function buildGrid(panelId: string): string[][] {
   return [['title'], ['terminal']];
 }
 
-/** In split mode, pick the right-column cell to jump to when → from the left.
- *  Prefers the user's last right-column position (so ← then → round-trips),
- *  falls back to the top of the right column (changed-files / shell row). */
-function pickRightColumnTarget(taskId: string, grid: string[][]): string | null {
-  const remembered = store.lastRightColFocus[taskId];
-  if (remembered && findInGrid(grid, remembered)) return remembered;
+/** In split mode, find the first focusable panel in the right column. */
+function pickTopRightColumnTarget(grid: string[][]): string | null {
   for (const row of grid) {
     for (let c = 1; c < row.length; c++) {
       const cell = row[c];
@@ -134,11 +128,6 @@ export function setTaskFocusedPanel(taskId: string, panel: string): void {
   setStore('focusedPanel', taskId, panel);
   setStore('sidebarFocused', false);
   setStore('placeholderFocused', false);
-  // Remember right-column visits so → from ai-terminal can return to where the
-  // user was instead of always jumping to the top of the right column.
-  if (!LEFT_COL_PANELS.has(panel)) {
-    setStore('lastRightColFocus', taskId, panel);
-  }
   triggerFocus(`${taskId}:${panel}`);
   scrollTaskIntoView(taskId);
 }
@@ -275,15 +264,14 @@ export function navigateRow(direction: 'up' | 'down'): void {
   }
 
   // Dead-end: in split mode, ↓ from ai-terminal when no prompt/shells anchor
-  // the left column's bottom would otherwise stop — enter the right column
-  // (the ← from any right-col cell will come back to ai-terminal).
+  // the left column's bottom would otherwise stop — enter the top-right panel.
   if (
     direction === 'down' &&
     store.taskSplitMode[taskId] &&
     pos.col === 0 &&
     current === 'ai-terminal'
   ) {
-    const target = pickRightColumnTarget(taskId, grid);
+    const target = pickTopRightColumnTarget(grid);
     if (target) setTaskFocusedPanel(taskId, target);
   }
 }
@@ -338,16 +326,13 @@ export function navigateColumn(direction: 'left' | 'right'): void {
     setTaskFocusedPanel(taskId, fallback);
   }
 
-  // In split mode, → from ai-terminal is row-aware: go to the last right-column
-  // cell the user visited, not the first match in findInGrid (which always
-  // returned `changed-files` at row 1 regardless of where they came from).
   if (
     direction === 'right' &&
     pos.col === 0 &&
     current === 'ai-terminal' &&
     store.taskSplitMode[taskId]
   ) {
-    const target = pickRightColumnTarget(taskId, grid);
+    const target = pickTopRightColumnTarget(grid);
     if (target) {
       setTaskFocusedPanel(taskId, target);
       return;
@@ -356,8 +341,6 @@ export function navigateColumn(direction: 'left' | 'right'): void {
 
   const row = grid[pos.row];
   const nextCol = direction === 'left' ? pos.col - 1 : pos.col + 1;
-
-  // Within-row movement
   if (nextCol >= 0 && nextCol < row.length) {
     setTaskFocusedPanel(taskId, row[nextCol]);
     return;

src/store/types.ts

@@ -230,7 +230,4 @@ export interface AppStore {
   focusMode: boolean;
   /** Per-task flag: true when the task is rendering its focus-mode two-column layout. */
   taskSplitMode: Record<string, boolean>;
-  /** Per-task memory of the last right-column cell focused, so crossing ai-terminal and back
-   *  with the arrow keys returns to where the user was instead of always jumping to `changed-files`. */
-  lastRightColFocus: Record<string, string>;
 }