/**
 * What has to let go when a session ends (#177): signing out takes the editor down while the page
 * stays up, so everything it registered outside itself needs a way back – the autosave's timer and
 * its `beforeunload` listener, and the handlers panels push into the focus manager. A handler left
 * behind would go on typing into an editor nobody can see.
 *
 * The editor as a whole is torn down in the browser (e2e step 45); the pieces are here.
 */
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import { CreateAssetCommand } from '../../src/core/commands/assetCommands';
import { createEmptyProject, type Project } from '../../src/core/model/Project';
import type { ProjectStore } from '../../src/core/store/ProjectStore';
import { attachAutosave } from '../../src/editor/autosave';
import { EditorState } from '../../src/editor/state';

/** Just enough `window` for the two modules under test; vitest runs these in node. */
function fakeWindow() {
  let next = 1;
  const timers = new Map<number, () => void>();
  const listeners: [string, unknown][] = [];
  return {
    listeners,
    /** Runs every timer that is still scheduled, newest first, as the browser eventually would. */
    fire: () => {
      for (const run of [...timers.values()]) run();
      timers.clear();
    },
    setTimeout: (fn: () => void) => {
      const id = next++;
      timers.set(id, fn);
      return id;
    },
    clearTimeout: (id: number) => void timers.delete(id),
    addEventListener: (type: string, fn: unknown) => void listeners.push([type, fn]),
    removeEventListener: (type: string, fn: unknown) => {
      const index = listeners.findIndex(([t, f]) => t === type && f === fn);
      if (index >= 0) listeners.splice(index, 1);
    },
  };
}

function savingStore(saves: Project[]): ProjectStore {
  return {
    list: () => Promise.resolve([]),
    load: () => Promise.reject(new Error('not used')),
    save: (project, revision) => {
      saves.push(project);
      return Promise.resolve(revision + 1);
    },
    create: () => Promise.reject(new Error('not used')),
    delete: () => Promise.resolve(),
  };
}

describe('autosave', () => {
  let win: ReturnType<typeof fakeWindow>;

  beforeEach(() => {
    win = fakeWindow();
    vi.stubGlobal('window', win);
  });
  afterEach(() => vi.unstubAllGlobals());

  const dirtyState = () => {
    const state = new EditorState();
    state.loadProject(createEmptyProject('p1', 'Teardown'), 1);
    state.execute(new CreateAssetCommand('sprite', 'Crate'));
    return state;
  };

  it('writes what is pending when it is flushed', async () => {
    const saves: Project[] = [];
    const state = dirtyState();
    const autosave = attachAutosave(state, savingStore(saves));
    expect(state.saveStatus).toBe('dirty');

    await autosave.flush();
    expect(saves).toHaveLength(1);
    expect(state.saveStatus).toBe('saved');
    expect(state.revision).toBe(2);
  });

  it('stops for good: no pending save fires, and the page listener is gone', async () => {
    const saves: Project[] = [];
    const state = dirtyState();
    const autosave = attachAutosave(state, savingStore(saves));
    expect(win.listeners.map(([type]) => type)).toEqual(['beforeunload']);

    autosave.stop();
    win.fire();
    await Promise.resolve();
    expect(saves).toEqual([]);
    expect(win.listeners).toEqual([]);
  });

  it('a change after the stop schedules nothing any more', async () => {
    const saves: Project[] = [];
    const state = dirtyState();
    const autosave = attachAutosave(state, savingStore(saves));
    await autosave.flush();
    autosave.stop();

    state.execute(new CreateAssetCommand('sprite', 'Box'));
    win.fire();
    await Promise.resolve();
    expect(saves).toHaveLength(1);
  });
});

describe('focus manager handlers', () => {
  beforeEach(() => vi.stubGlobal('window', fakeWindow()));
  afterEach(() => vi.unstubAllGlobals());

  it('hands back the call that removes a global key handler', async () => {
    const { FocusManager } = await import('../../src/ui/FocusManager');
    const { Container } = await import('pixi.js');
    const focus = new FocusManager(new Container());
    const seen: string[] = [];
    const remove = focus.onGlobalKey((event) => {
      seen.push(event.key);
      return false;
    });
    expect(focus.globalHandlers).toHaveLength(1);

    remove();
    expect(focus.globalHandlers).toEqual([]);
    // A second call is harmless – a widget may be destroyed after the editor already let go.
    remove();
    expect(seen).toEqual([]);
  });

  it('hands back the call that removes a focus-change handler', async () => {
    const { FocusManager } = await import('../../src/ui/FocusManager');
    const { Container } = await import('pixi.js');
    const focus = new FocusManager(new Container());
    let runs = 0;
    const remove = focus.onFocusChange(() => runs++);
    const other = focus.onFocusChange(() => runs++);
    expect(focus.changeHandlers).toHaveLength(2);

    remove();
    expect(focus.changeHandlers).toHaveLength(1);
    other();
    expect(focus.changeHandlers).toEqual([]);
    expect(runs).toBe(0);
  });
});