/**
 * A game hears of the end of what it played (#373): a playing of a pattern or song tells its sink
 * once nothing of it is left, the sink keeps it, and On music finished and On sound finished run for
 * what the run itself played – once, with "stopped" where a stop ended it.
 */
import { beforeAll, describe, expect, it } from 'vitest';
import { CreateAssetCommand, CreateSoundCommand } from '../../src/core/commands/assetCommands';
import { PlaceAssetCommand } from '../../src/core/commands/sceneObjectCommands';
import { Playbacks, type SequencePlay } from '../../src/core/music/playbacks';
import { INTERVAL } from '../../src/core/music/Scheduler';
import { GameRun } from '../../src/runtime/GameRun';
import { loadPhysics, readyPhysics } from '../../src/runtime/physics/engine';
import { type AudioSink, type EndedPlay, SILENT_AUDIO } from '../../src/runtime/systems/Audio';
import { Input } from '../../src/runtime/systems/Input';
import { PlayedEnds } from '../../src/runtime/systems/playedEnds';
import { graphEditor, makeBehavior, makeSpriteScene, place, startWorld } from '../helpers';

const Q = 480;

/** An audio clock moved by hand, its notes over as soon as they are struck; what ends is kept. */
function fakeHost() {
  const host = {
    time: 0,
    pumps: new Set<() => void>(),
    loading: [] as (() => void)[],
    timers: [] as { at: number; then: () => void }[],
    ended: [] as EndedPlay[],
  };
  const playbacks = new Playbacks({
    now: () => host.time,
    latency: () => 0,
    playing: () => false,
    stop: () => {},
    wake: (pump) => {
      host.pumps.add(pump);
      return () => host.pumps.delete(pump);
    },
    prepare: () => new Promise<void>((resolve) => host.loading.push(resolve)),
    level: () => {},
    after: (at, then) => host.timers.push({ at, then }),
    ended: (id, name, stopped) => host.ended.push({ id, name, stopped }),
  });
  const run = (seconds: number) => {
    const end = host.time + seconds;
    while (host.time + INTERVAL <= end + 1e-9) {
      host.time += INTERVAL;
      for (const pump of [...host.pumps]) pump();
      for (const timer of host.timers.filter((t) => t.at <= host.time + 1e-9)) {
        host.timers.splice(host.timers.indexOf(timer), 1);
        timer.then();
      }
    }
  };
  const loaded = async () => {
    for (const resolve of host.loading.splice(0)) resolve();
    await Promise.resolve();
  };
  return { host, playbacks, run, loaded };
}

/** A bar of four quarters at 120 BPM: two seconds long. */
function bar(loop: boolean): SequencePlay {
  let next = 100;
  return {
    sequence: {
      notes: [0, 1, 2, 3].map((i) => ({
        tick: i * Q,
        length: Q / 2,
        note: 60 + i,
        velocity: 1,
        instrument: 'p',
      })),
    },
    tempo: 120,
    length: 4 * Q,
    loop: loop ? { start: 0, end: 4 * Q } : null,
    needs: { layers: [], files: [] },
    strike: () => next++,
  };
}

describe('the end of a playing', () => {
  it('is told once it is played to its end, once, not stopped', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    playbacks.start(7, 'pattern:a', bar(false), '');
    await loaded();
    // Heard from 0.05 s on, so over at 2.05 s; its last note is long gone and the rest planned by then.
    run(2);
    playbacks.current();
    expect(host.ended).toEqual([]);
    run(0.1);
    playbacks.current();
    playbacks.current();
    expect(host.ended).toEqual([{ id: 7, name: 'pattern:a', stopped: false }]);
  });

  it('with a loop never by itself, only by a stop – after its fade out', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    playbacks.start(7, 'song:a', bar(true), '');
    await loaded();
    run(9);
    playbacks.current();
    expect(host.ended).toEqual([]);
    playbacks.stopNamed('song:a', false, 1);
    run(0.9);
    expect(host.ended).toEqual([]);
    run(0.2);
    expect(host.ended).toEqual([{ id: 7, name: 'song:a', stopped: true }]);
  });

  it('stopped while its files load, by its owner, it is told as stopped', () => {
    const { host, playbacks } = fakeHost();
    playbacks.start(7, 'pattern:a', bar(false), 'logic');
    playbacks.stopOwner('logic');
    expect(host.ended).toEqual([{ id: 7, name: 'pattern:a', stopped: true }]);
  });

  it('of a switch only once the number is over, by the song heard last (#338)', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    playbacks.start(7, 'song:a', bar(true), '');
    await loaded();
    run(1);
    playbacks.switchTo(7, 8, 'song:b', bar(true), '', (clock) => clock.soonest, 0);
    await loaded();
    run(1);
    expect(playbacks.named(7).map((p) => p.name)).toEqual(['song:b']);
    expect(host.ended).toEqual([]);
    playbacks.stopId(7);
    expect(host.ended).toEqual([{ id: 7, name: 'song:b', stopped: true }]);
  });

  it('of a switch stopped while the two cross, by the one it switched to', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    playbacks.start(7, 'song:a', bar(true), '');
    await loaded();
    run(1);
    playbacks.switchTo(7, 8, 'song:b', bar(true), '', (clock) => clock.soonest, 2);
    await loaded();
    run(0.5);
    expect(playbacks.named(7).map((p) => p.name)).toEqual(['song:a', 'song:b']);
    playbacks.stopId(7);
    expect(host.ended).toEqual([{ id: 7, name: 'song:b', stopped: true }]);
  });

  it('of a switch stopped before it is heard, by the song heard then', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    playbacks.start(7, 'song:a', bar(true), '');
    await loaded();
    run(1);
    playbacks.switchTo(7, 8, 'song:b', bar(true), '', (clock) => clock.soonest, 0);
    playbacks.stopId(7);
    expect(host.ended).toEqual([{ id: 7, name: 'song:a', stopped: true }]);
  });
});

describe('PlayedEnds', () => {
  it('tells only what the run played, each once, a playing by the song or pattern it ended as', () => {
    const ends = new PlayedEnds();
    ends.sound(3, 'blip');
    ends.playing(4);
    ends.playing(5);
    ends.playing(0);
    const log: EndedPlay[] = [
      { id: 2, name: 'x.ogg', stopped: false },
      { id: 3, name: 'b.ogg', stopped: true },
      { id: 4, name: 'song:boss', stopped: false },
      { id: 5, name: 'pattern:riff', stopped: true },
    ];
    expect(ends.follow(log)).toEqual([
      { id: 3, kind: 'sound', asset: 'blip', stopped: true },
      { id: 4, kind: 'song', asset: 'boss', stopped: false },
      { id: 5, kind: 'pattern', asset: 'riff', stopped: true },
    ]);
    expect(ends.follow(log)).toEqual([]);
  });
});

/**
 * A sink that plays its patterns and songs on real playings, on the hand-moved clock, and makes a
 * voice of each sound that lasts until `endVoice` or a stop.
 */
function playingSink() {
  const fake = fakeHost();
  let next = 1;
  const voices = new Map<number, string>();
  const endVoice = (id: number, stopped: boolean) => {
    const file = voices.get(id);
    if (file === undefined) return;
    voices.delete(id);
    fake.host.ended.push({ id, name: file, stopped });
  };
  const audio: AudioSink = {
    ...SILENT_AUDIO,
    play: (file) => {
      voices.set(next, file);
      return next++;
    },
    playSequence: (name, play, owner) => {
      const id = next++;
      fake.playbacks.start(id, name, play, owner);
      return id;
    },
    stopSequence: (name, letRing, fade) => fake.playbacks.stopNamed(name, letRing, fade),
    stopPlayback: (id, fade) => fake.playbacks.stopId(id, false, fade),
    stop: (file) => {
      if (file === '') fake.playbacks.stopNamed('');
      for (const [id, of] of voices) if (file === '' || of === file) endVoice(id, true);
    },
    stopVoice: (id) => endVoice(id, true),
    stopOwner: (owner) => fake.playbacks.stopOwner(owner),
    playing: (id) => voices.has(id) || fake.playbacks.has(id),
    endings: () => (fake.playbacks.current(), fake.host.ended),
  };
  return { ...fake, audio, endVoice };
}

/** A song and a pattern, each played without a loop on start, and a behavior that logs what ends. */
function listening() {
  const f = makeSpriteScene('Box');
  const create = (type: 'song' | 'pattern', name: string) => {
    const command = new CreateAssetCommand(type, name);
    f.stack.execute(command);
    return command.asset.id;
  };
  const song = create('song', 'Theme');
  const pattern = create('pattern', 'Riff');
  const blip = new CreateSoundCommand('Blip', `${'a1'.repeat(32)}.wav`);
  f.stack.execute(blip);
  const behavior = makeBehavior(f, 'Logic');
  place(f, behavior.id, { x: 0, y: 0 });
  const edit = graphEditor(f, behavior);
  /** An event that logs `prefix`, its number and "stopped", run together. */
  const logs = (type: string, params: Record<string, string>, prefix: string, number: string) => {
    const event = edit.addNode(type, params);
    const join = edit.addNode('Join');
    const first = edit.addNode('Join', { a: prefix });
    edit.connect(event, number, first, 'b');
    edit.connect(first, 'text', join, 'a');
    edit.connect(event, 'stopped', join, 'b');
    const log = edit.addNode('Log');
    edit.connect(event, 'exec', log, 'exec');
    edit.connect(join, 'text', log, 'message');
    return event;
  };
  return { ...f, song, pattern, sound: blip.asset.id, edit, logs };
}

describe('On music finished', () => {
  it('runs once when a song without a loop is over, not stopped; one with a loop never by itself', async () => {
    const f = listening();
    const start = f.edit.addNode('OnStart');
    const once = f.edit.addNode('PlaySong', { song: f.song, loop: false });
    const round = f.edit.addNode('PlaySong', { song: f.song, loop: true });
    f.edit.connect(start, 'exec', once, 'exec');
    f.edit.connect(once, 'exec', round, 'exec');
    f.logs('OnMusicFinished', {}, 'end ', 'playback');
    const { audio, playbacks, run, loaded } = playingSink();
    const { world, frame } = startWorld(f, { behaviors: true, audio });
    frame();
    const [first, second] = playbacks.current().map((p) => p.id);
    await loaded();
    const length = playbacks.current()[0]!.time.length / (2 * Q);
    run(length - 0.5);
    frame();
    expect(world.log).toEqual([]);
    run(1);
    frame();
    frame();
    expect(world.log).toEqual([`end ${first}false`]);
    run(3 * length);
    frame();
    expect(world.log).toHaveLength(1);
    expect(playbacks.has(second!)).toBe(true);
  });

  it('runs with "stopped" after Stop song, and hears only what its Song, Pattern or "playback" picks', async () => {
    const f = listening();
    const start = f.edit.addNode('OnStart');
    const song = f.edit.addNode('PlaySong', { song: f.song, loop: true });
    const again = f.edit.addNode('PlaySong', { song: f.song, loop: true });
    f.edit.connect(start, 'exec', song, 'exec');
    f.edit.connect(song, 'exec', again, 'exec');
    f.logs('OnMusicFinished', { pattern: f.pattern }, 'pattern ', 'playback');
    f.logs('OnMusicFinished', { song: f.song }, 'song ', 'playback');
    // The sink numbers the two playings 1 and 2.
    const picked = f.logs('OnMusicFinished', {}, 'picked ', 'playback');
    f.edit.connect(f.edit.addNode('Number', { value: 1 }), 'value', picked, 'playback');
    const other = f.logs('OnMusicFinished', {}, 'other ', 'playback');
    f.edit.connect(f.edit.addNode('Number', { value: 2 }), 'value', other, 'playback');
    const key = f.edit.addNode('OnKeyDown', { key: 's' });
    const stop = f.edit.addNode('StopSong', { song: f.song });
    f.edit.connect(key, 'exec', stop, 'exec');
    const { audio, playbacks, loaded } = playingSink();
    const { world, frame, input } = startWorld(f, { behaviors: true, audio });
    frame();
    expect(playbacks.current().map((p) => p.id)).toEqual([1, 2]);
    await loaded();
    input.press('s');
    frame();
    frame();
    expect(world.log).toEqual(['song 1true', 'song 2true', 'picked 1true', 'other 2true']);
  });
});

describe('On sound finished', () => {
  it('runs once for a sound this game played, by its Sound or its "voice", with "stopped" where stopped', () => {
    const f = listening();
    const start = f.edit.addNode('OnStart');
    const first = f.edit.addNode('PlaySound', { sound: f.sound });
    const second = f.edit.addNode('PlaySound', { sound: f.sound });
    f.edit.connect(start, 'exec', first, 'exec');
    f.edit.connect(first, 'exec', second, 'exec');
    f.logs('OnSoundFinished', {}, 'any ', 'voice');
    f.logs('OnSoundFinished', { sound: f.sound }, 'blip ', 'voice');
    f.logs('OnSoundFinished', { sound: 'other' }, 'other ', 'voice');
    const picked = f.logs('OnSoundFinished', {}, 'second ', 'voice');
    f.edit.connect(f.edit.addNode('Number', { value: 2 }), 'value', picked, 'voice');
    f.logs('OnMusicFinished', {}, 'music ', 'playback');
    const key = f.edit.addNode('OnKeyDown', { key: 's' });
    const stop = f.edit.addNode('StopSound', { sound: f.sound });
    f.edit.connect(key, 'exec', stop, 'exec');
    const { audio, endVoice } = playingSink();
    const { world, frame, input } = startWorld(f, { behaviors: true, audio });
    frame();
    expect([audio.playing!(1), audio.playing!(2)]).toEqual([true, true]);
    endVoice(1, false);
    frame();
    frame();
    expect(world.log).toEqual(['any 1false', 'blip 1false']);
    input.press('s');
    frame();
    frame();
    expect(world.log.slice(2)).toEqual(['any 2true', 'blip 2true', 'second 2true']);
  });

  it('hears nothing a run did not play itself', () => {
    const f = listening();
    f.logs('OnSoundFinished', {}, 'any ', 'voice');
    f.logs('OnMusicFinished', {}, 'music ', 'playback');
    const { audio, playbacks } = playingSink();
    audio.play('a.wav', 1, false, 'sound-preview');
    playbacks.start(9, `song:${f.song}`, bar(false), 'pattern-preview');
    playbacks.stopId(9);
    audio.stopVoice(1);
    const { world, frame } = startWorld(f, { behaviors: true, audio });
    frame();
    frame();
    expect(world.log).toEqual([]);
  });
});

describe('a run', () => {
  beforeAll(async () => {
    await loadPhysics();
  });

  it('hears a sound it played in one scene end in the next', () => {
    const f = listening();
    const start = f.edit.addNode('OnStart');
    const play = f.edit.addNode('PlaySound', { sound: f.sound, detached: true });
    const load = f.edit.addNode('LoadScene');
    f.edit.connect(start, 'exec', play, 'exec');
    f.edit.connect(play, 'exec', load, 'exec');
    const next = new CreateAssetCommand('scene', 'Level 2');
    f.stack.execute(next);
    load.params.scene = next.asset.id;
    const hearing = makeBehavior(f, 'Ears');
    f.stack.execute(new PlaceAssetCommand(next.asset.id, hearing.id, { x: 0, y: 0 }, ''));
    const ears = graphEditor(f, hearing);
    const log = ears.addNode('Log', { message: 'heard' });
    ears.connect(ears.addNode('OnSoundFinished', { sound: f.sound }), 'exec', log, 'exec');
    const { audio, endVoice } = playingSink();
    const run = GameRun.start(f.project, f.sceneId, new Input(), {
      audio,
      physics: readyPhysics()!,
      clock: { scale: 1 },
      saves: { read: () => ({}), write: () => {} },
    });
    expect(run.tick(1 / 60, 1 / 60)).toBe('scene');
    run.tick(1 / 60, 1 / 60);
    endVoice(1, false);
    run.tick(1 / 60, 1 / 60);
    expect(run.world.log).toEqual(['heard']);
  });
});