import type * as Pixi from 'pixi.js';
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';

/**
 * When the video library lets a player go (#402): after 2 s nobody asked for it, but never while
 * the page is hidden. Chrome draws no frames for a hidden page and so nothing asks, while the
 * sweeper's timer goes on; a sprite still wearing the video lost it and Pixi warned about the
 * destroyed source on the way back.
 */
// Pixi's own video source reads the page as it is made; a plain source stands in for it.
vi.mock('pixi.js', async (load) => {
  const pixi = await load<typeof Pixi>();
  class VideoSource extends pixi.TextureSource {
    constructor() {
      super({ width: 320, height: 180 });
    }
  }
  return { ...pixi, VideoSource };
});

const KEY = `video:a1b2c3d4e5f6/${'c7'.repeat(32)}.mp4#0~0~1~1`;

let videosMade = 0;

function fakeVideo() {
  videosMade += 1;
  return {
    muted: false,
    playsInline: false,
    preload: '',
    src: '',
    currentTime: 0,
    loop: false,
    paused: true,
    addEventListener: () => {},
    requestVideoFrameCallback: () => 0,
    play: () => Promise.resolve(),
    pause: () => {},
    removeAttribute: () => {},
    load: () => {},
  };
}

const page = { hidden: false, listeners: [] as (() => void)[] };

function setHidden(hidden: boolean): void {
  page.hidden = hidden;
  for (const listener of page.listeners) listener();
}

async function freshLibrary() {
  const { VideoLibrary } = await import('../../src/viewport/VideoLibrary');
  return new VideoLibrary();
}

describe('VideoLibrary sweeping', () => {
  beforeEach(() => {
    vi.useFakeTimers({ toFake: ['setInterval', 'clearInterval', 'performance'] });
    page.hidden = false;
    page.listeners = [];
    vi.stubGlobal('document', {
      get hidden() {
        return page.hidden;
      },
      addEventListener: (_type: string, listener: () => void) => page.listeners.push(listener),
      createElement: fakeVideo,
    });
  });

  afterEach(() => {
    vi.useRealTimers();
    vi.unstubAllGlobals();
  });

  it('lets a player go that nobody asked for in 2 s', async () => {
    const videos = await freshLibrary();
    videos.get(KEY);
    vi.advanceTimersByTime(4100);
    expect(videos.debugInfo()).toEqual([]);
  });

  it('keeps it while the page is hidden, however long', async () => {
    const videos = await freshLibrary();
    videos.get(KEY);
    setHidden(true);
    vi.advanceTimersByTime(60_000);
    expect(videos.debugInfo()).toHaveLength(1);
  });

  it('does not count the time hidden as idle once the page is back', async () => {
    const videos = await freshLibrary();
    videos.get(KEY);
    setHidden(true);
    vi.advanceTimersByTime(60_000);
    setHidden(false);
    vi.advanceTimersByTime(1900);
    expect(videos.debugInfo()).toHaveLength(1);
    vi.advanceTimersByTime(2200);
    expect(videos.debugInfo()).toEqual([]);
  });

  it('keeps a driven player that is only worn, as by a sprite switched off', async () => {
    const videos = await freshLibrary();
    const ref = { file: KEY, smooth: true, rect: null, sourceWidth: 320, sourceHeight: 180, slice: null };
    const props = { videoClock: 'driven', videoTime: 1.2 };
    videosMade = 0;
    for (let ms = 0; ms < 6000; ms += 100) {
      videos.wear(ref, props, 'view2:a', 'none');
      vi.advanceTimersByTime(100);
    }
    // Let go and opened again would be a second video, loading while the sprite shows white.
    expect(videosMade).toBe(1);
    expect(videos.debugInfo().map(({ key }) => key)).toEqual([`${KEY}@view2:a`]);
  });
});

describe('VideoLibrary driven players (#404)', () => {
  beforeEach(() => {
    vi.stubGlobal('document', { hidden: false, addEventListener: () => {}, createElement: fakeVideo });
  });

  afterEach(() => {
    vi.unstubAllGlobals();
    vi.restoreAllMocks();
  });

  const REF = { file: KEY, smooth: true, rect: null, sourceWidth: 320, sourceHeight: 180, slice: null };

  it('leaves a sprite with a free clock on the shared player', async () => {
    const videos = await freshLibrary();
    expect(videos.wear(REF, { videoTime: 1 }, 'view1:a', 'none')).toBe(REF);
    expect(videos.debugInfo()).toEqual([]);
  });

  it('gives every wearer of a driven video a player of its own, opened at its time', async () => {
    const videos = await freshLibrary();
    const a = videos.wear(REF, { videoClock: 'driven', videoTime: 0.5 }, 'view1:a', 'none');
    const b = videos.wear(REF, { videoClock: 'driven', videoTime: 1.25 }, 'view1:b', 'none');
    expect([a.file, b.file]).toEqual([`${KEY}@view1:a`, `${KEY}@view1:b`]);
    expect(videos.debugInfo().map(({ key, time }) => [key, time])).toEqual([
      [`${KEY}@view1:a`, 0.5],
      [`${KEY}@view1:b`, 1.25],
    ]);
  });

  it('reads the speed by the time of the frame, not by when the frame got round to it', async () => {
    const frame = { at: 0 };
    vi.stubGlobal('document', {
      hidden: false,
      addEventListener: () => {},
      createElement: fakeVideo,
      timeline: {
        get currentTime() {
          return frame.at;
        },
      },
    });
    // The first frames are drawn 45 ms late, as on a busy page; the time runs at 1x by the frames.
    let late = 45;
    vi.spyOn(performance, 'now').mockImplementation(() => frame.at + late);
    const videos = await freshLibrary();
    for (let i = 0; i <= 36; i++) {
      frame.at = (i * 1000) / 60;
      if (i === 7) late = 0;
      videos.wear(REF, { videoClock: 'driven', videoTime: i / 60 }, 'view1:a', 'none');
    }
    expect(videos.debugInfo()[0]!.speed).toBeCloseTo(1, 6);
  });

  it('lands a seek that Chrome hands over no frame for', async () => {
    vi.useFakeTimers({ toFake: ['setTimeout', 'setInterval', 'clearInterval'] });
    const events = new Map<string, (() => void)[]>();
    let frames: (() => void)[] = [];
    const element = {
      ...fakeVideo(),
      seeking: false,
      ended: false,
      duration: 2,
      playbackRate: 1,
      readyState: 4,
      videoWidth: 320,
      videoHeight: 180,
      at: 0,
      get currentTime() {
        return this.at;
      },
      set currentTime(time: number) {
        this.at = time;
        this.seeking = true;
      },
      addEventListener: (type: string, listener: () => void) =>
        events.set(type, [...(events.get(type) ?? []), listener]),
      requestVideoFrameCallback: (callback: () => void) => frames.push(callback),
    };
    const fire = (type: string) => events.get(type)?.forEach((listener) => listener());
    const seekDone = () => {
      element.seeking = false;
      fire('seeked');
    };
    vi.stubGlobal('document', { hidden: false, addEventListener: () => {}, createElement: () => element });
    const videos = await freshLibrary();
    const key = videos.wear(REF, { videoClock: 'driven', videoTime: 0.5 }, 'view1:a', 'none').file;
    fire('loadeddata');
    seekDone();
    [frames] = [[], ...frames.map((frame) => frame())];
    expect(videos.showsAsked(key)).toBe(true);
    // Switched on at 1.2 s: the seek is done, and no frame follows it.
    videos.wear(REF, { videoClock: 'driven', videoTime: 1.2 }, 'view1:a', 'none');
    expect(videos.showsAsked(key)).toBe(false);
    seekDone();
    vi.advanceTimersByTime(200);
    vi.useRealTimers();
    expect(videos.showsAsked(key)).toBe(true);
  });

  it('gives a player opened behind another tab its first picture, with no frame handed over (#423)', async () => {
    vi.useFakeTimers({ toFake: ['setInterval', 'clearInterval'] });
    const page = { hidden: true };
    const events = new Map<string, () => void>();
    const element = {
      ...fakeVideo(),
      seeking: false,
      ended: false,
      duration: 2,
      playbackRate: 1,
      readyState: 4,
      networkState: 1,
      addEventListener: (type: string, listener: () => void) => events.set(type, listener),
      // Behind another tab Chrome calls none of these.
      requestVideoFrameCallback: () => 0,
    };
    vi.stubGlobal('document', {
      get hidden() {
        return page.hidden;
      },
      addEventListener: () => {},
      createElement: () => element,
    });
    const videos = await freshLibrary();
    const key = videos.wear(REF, { videoClock: 'driven', videoTime: 0.5 }, 'view1:a', 'game').file;
    events.get('loadeddata')!();
    vi.advanceTimersByTime(100);
    const behind = videos.hasPicture(key);
    // In front Chrome hands over the frame, and the player waits for it.
    page.hidden = false;
    const front = videos.wear(REF, { videoClock: 'driven', videoTime: 0.5 }, 'view1:b', 'game').file;
    events.get('loadeddata')!();
    vi.advanceTimersByTime(100);
    vi.useRealTimers();
    expect(behind).toBe(true);
    expect(videos.hasPicture(front)).toBe(false);
  });

  it('holds a driven player quiet as soon as its wearer is gone, as an ended composition item', async () => {
    vi.useFakeTimers({ toFake: ['setInterval', 'clearInterval', 'performance'] });
    const events = new Map<string, () => void>();
    let frames: (() => void)[] = [];
    const element = {
      ...fakeVideo(),
      ended: false,
      duration: 10,
      playbackRate: 1,
      seeking: false,
      readyState: 4,
      videoWidth: 320,
      videoHeight: 180,
      play() {
        this.paused = false;
        return Promise.resolve();
      },
      pause() {
        this.paused = true;
      },
      addEventListener: (type: string, listener: () => void) => events.set(type, listener),
      requestVideoFrameCallback: (callback: () => void) => frames.push(callback),
    };
    vi.stubGlobal('document', { hidden: false, addEventListener: () => {}, createElement: () => element });
    const { soundLibrary } = await import('../../src/viewport/SoundLibrary');
    vi.spyOn(soundLibrary, 'mediaInput').mockReturnValue(null);
    const videos = await freshLibrary();
    const props = { videoClock: 'driven', videoTime: 0 };
    videos.wear(REF, props, 'view1:a', 'game');
    events.get('loadeddata')!();
    [frames] = [[], ...frames.map((frame) => frame())];
    // Worn at 1x for a second, heard.
    for (let ms = 0; ms <= 1000; ms += 1000 / 60) {
      element.currentTime = ms / 1000;
      videos.wear(REF, { ...props, videoTime: ms / 1000 }, 'view1:a', 'game');
      vi.advanceTimersByTime(1000 / 60);
    }
    expect([element.paused, element.muted]).toEqual([false, false]);
    // The item ends: nothing wears the player any more. Let go only after 2 s, it played on heard.
    vi.advanceTimersByTime(200);
    expect([element.paused, element.muted]).toEqual([true, true]);
    expect(videos.debugInfo()).toHaveLength(1);
    vi.useRealTimers();
  });

  it('holds a free player quiet once no sprite wears it, and plays it on when one does (#420)', async () => {
    vi.useFakeTimers({ toFake: ['setInterval', 'clearInterval', 'performance'] });
    const page = { hidden: false };
    const events = new Map<string, () => void>();
    let frames: (() => void)[] = [];
    const element = {
      ...fakeVideo(),
      play() {
        this.paused = false;
        return Promise.resolve();
      },
      pause() {
        this.paused = true;
      },
      addEventListener: (type: string, listener: () => void) => events.set(type, listener),
      requestVideoFrameCallback: (callback: () => void) => frames.push(callback),
    };
    vi.stubGlobal('document', {
      get hidden() {
        return page.hidden;
      },
      addEventListener: () => {},
      createElement: () => element,
    });
    const { soundLibrary } = await import('../../src/viewport/SoundLibrary');
    vi.spyOn(soundLibrary, 'mediaInput').mockReturnValue(null);
    const videos = await freshLibrary();
    const drawFor = (ms: number) => {
      for (let at = 0; at < ms; at += 1000 / 60) {
        videos.get(KEY);
        vi.advanceTimersByTime(1000 / 60);
      }
    };
    videos.get(KEY);
    events.get('loadeddata')!();
    [frames] = [[], ...frames.map((frame) => frame())];
    videos.startRun();
    drawFor(1000);
    const state = () => [element.paused, element.muted];
    expect(state()).toEqual([false, false]);
    // Its sprite is destroyed: held and quiet at once, not heard until it is let go 2-4 s later.
    vi.advanceTimersByTime(200);
    expect(state()).toEqual([true, true]);
    // A run started meanwhile takes it back to its start, still quiet.
    videos.startRun();
    vi.advanceTimersByTime(200);
    expect(state()).toEqual([true, true]);
    // Worn again before it is let go: it plays on, heard, the same video.
    videosMade = 0;
    drawFor(500);
    expect([...state(), videosMade]).toEqual([false, false, 0]);
    // A hidden page draws nothing, and asks for nothing: it plays on all the same.
    page.hidden = true;
    vi.advanceTimersByTime(1000);
    expect(state()).toEqual([false, false]);
    vi.useRealTimers();
  });

  it('tells a view whether one of its driven players still waits for its first picture', async () => {
    const videos = await freshLibrary();
    videos.get(KEY);
    expect(videos.loading('view12')).toBe(false);
    const worn = videos.wear(REF, { videoClock: 'driven', videoTime: 0 }, 'view12:a', 'none');
    expect(videos.hasPicture(worn.file)).toBe(false);
    // A run waits only for its own view: view12 is neither view1 nor view2.
    expect([videos.loading('view12'), videos.loading('view1'), videos.loading('view2')]).toEqual([
      true,
      false,
      false,
    ]);
  });
});