/**
 * A game plays a pattern through Play pattern and ends it through Stop pattern: each playing on a
 * scheduler of its own, numbered, owned and stopped like a voice, and gone by itself once played
 * to its end.
 */
import { describe, expect, it } from 'vitest';
import {
  CreateAssetCommand,
  CreateSoundCommand,
  SetAssetPropertyCommand,
} from '../../src/core/commands/assetCommands';
import { SetPatternNotesCommand } from '../../src/core/commands/patternCommands';
import type { InstrumentAsset } from '../../src/core/model/Asset';
import { Playbacks, type SequencePlay } from '../../src/core/music/playbacks';
import { INTERVAL, LEAD, type ScheduledNote } from '../../src/core/music/Scheduler';
import { type AudioSink, SILENT_AUDIO } from '../../src/runtime/systems/Audio';
import { graphEditor, makeBehavior, makeSpriteScene, place, startWorld } from '../helpers';

const FILE = `${'a1'.repeat(32)}.wav`;
const Q = 480;

/** An audio clock moved by hand, every voice sounding until it is stopped or let go. */
function fakeHost() {
  const host = {
    time: 0,
    sounding: new Set<number>(),
    stopped: [] as { voices: number[]; letRing: boolean }[],
    pumps: new Set<() => void>(),
    loading: [] as (() => void)[],
  };
  const playbacks = new Playbacks({
    now: () => host.time,
    latency: () => 0,
    playing: (voice) => host.sounding.has(voice),
    stop: (voices, letRing = false) => {
      host.stopped.push({ voices: [...voices], letRing });
      for (const voice of voices) host.sounding.delete(voice);
    },
    wake: (pump) => {
      host.pumps.add(pump);
      return () => host.pumps.delete(pump);
    },
    prepare: () => new Promise<void>((resolve) => host.loading.push(resolve)),
  });
  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();
    }
  };
  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. Its voices sound in `sounding` until stopped. */
function bar(struck: ScheduledNote[], loop: boolean, sounding = new Set<number>()): 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: 'piano',
      })),
    },
    tempo: 120,
    length: 4 * Q,
    loop,
    layers: [],
    strike: (note) => {
      struck.push(note);
      sounding.add(next);
      return next++;
    },
  };
}

describe('the patterns a game plays', () => {
  it('waits for its files, then plays the whole pattern once and is gone when its last note is', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    const struck: ScheduledNote[] = [];
    playbacks.start(7, 'pattern:a', bar(struck, false, host.sounding), 'logic');
    run(0.5);
    expect(struck).toEqual([]);
    await loaded();
    run(3);
    expect(struck.map((n) => n.note)).toEqual([60, 61, 62, 63]);
    struck.forEach((n, i) => expect(n.at - struck[0]!.at).toBeCloseTo(i * 0.5, 9));
    expect(host.pumps.size).toBe(0);
    expect(playbacks.has(7)).toBe(true);
    host.sounding.clear();
    expect(playbacks.has(7)).toBe(false);
  });

  it('with loop runs round and round, 2 s to the round, until it is stopped', async () => {
    const { host, playbacks, run, loaded } = fakeHost();
    const struck: ScheduledNote[] = [];
    playbacks.start(7, 'pattern:a', bar(struck, true, host.sounding), '');
    await loaded();
    run(5);
    expect(struck.map((n) => n.note).slice(0, 10)).toEqual([60, 61, 62, 63, 60, 61, 62, 63, 60, 61]);
    expect(struck[4]!.at - struck[0]!.at).toBeCloseTo(2, 9);
    expect(struck[0]!.at).toBeCloseTo(LEAD, 9);
    playbacks.stopId(7, true);
    expect(host.stopped.at(-1)?.letRing).toBe(true);
    expect([playbacks.has(7), host.pumps.size]).toEqual([false, 0]);
  });

  it('never starts when it was stopped while its files were loading', async () => {
    const { host, playbacks, loaded, run } = fakeHost();
    const struck: ScheduledNote[] = [];
    playbacks.start(7, 'pattern:a', bar(struck, true), 'logic');
    playbacks.stopOwner('logic');
    await loaded();
    run(1);
    expect([struck.length, host.pumps.size, playbacks.has(7)]).toEqual([0, 0, false]);
  });

  it('stops by name, every one for no name, by owner – and an owner of nobody stops nothing', async () => {
    const { playbacks, loaded } = fakeHost();
    playbacks.start(1, 'pattern:a', bar([], true), 'x');
    playbacks.start(2, 'pattern:a', bar([], true), '');
    playbacks.start(3, 'pattern:b', bar([], true), 'y');
    playbacks.start(4, 'pattern:c', bar([], true), '');
    await loaded();
    playbacks.stopOwner('');
    expect(playbacks.current().map((p) => p.id)).toEqual([1, 2, 3, 4]);
    playbacks.stopNamed('pattern:a');
    expect(playbacks.current().map((p) => p.id)).toEqual([3, 4]);
    playbacks.stopOwner('y');
    expect(playbacks.current().map((p) => p.id)).toEqual([4]);
    playbacks.stopNamed('');
    expect(playbacks.current()).toEqual([]);
  });
});

/** A scene whose behavior plays a pattern of C4 and E4 on start, through an instrument of one sample. */
function playingPattern(params: Record<string, string | number | boolean> = {}, instrument = true) {
  const f = makeSpriteScene('Box');
  const sound = new CreateSoundCommand('Blip', FILE);
  f.stack.execute(sound);
  const ins = new CreateAssetCommand('instrument', 'Lead');
  f.stack.execute(ins);
  const lead = ins.asset as InstrumentAsset;
  lead.graph.nodes.find((n) => n.type === 'InstrumentSample')!.params.sound = sound.asset.id;
  const pattern = new CreateAssetCommand('pattern', 'Tune');
  f.stack.execute(pattern);
  const id = pattern.asset.id;
  if (instrument) f.stack.execute(new SetAssetPropertyCommand(id, 'instrument', lead.id));
  f.stack.execute(new SetAssetPropertyCommand(id, 'tempo', 90));
  f.stack.execute(new SetAssetPropertyCommand(id, 'bars', 2));
  f.stack.execute(
    new SetPatternNotesCommand(id, [
      { id: 'n1', tick: 0, length: Q, note: 60, velocity: 0.5 },
      { id: 'n2', tick: Q, length: Q, note: 64, velocity: 1 },
    ]),
  );
  const behavior = makeBehavior(f, 'Logic');
  const box = place(f, f.spriteId, { x: 0, y: 0 });
  place(f, behavior.id, { x: 0, y: 0 }, box);
  const edit = graphEditor(f, behavior);
  const start = edit.addNode('OnStart');
  const play = edit.addNode('PlayPattern', { pattern: id, volume: 0.5, ...params });
  edit.connect(start, 'exec', play, 'exec');
  return { ...f, patternId: id, lead, behavior, edit, play };
}

function recordingAudio() {
  const sink = {
    ...SILENT_AUDIO,
    sequences: [] as { name: string; play: SequencePlay; owner: string }[],
    notes: [] as {
      name: string;
      volume: number;
      owner: string;
      duration: number;
      at?: number;
      tempo?: number;
    }[],
    stoppedSequences: [] as string[],
    stoppedVoices: [] as number[],
    playSequence: (name: string, play: SequencePlay, owner: string) => {
      sink.sequences.push({ name, play, owner });
      return 1000 + sink.sequences.length;
    },
    playNote: ((name, _layers, _params, volume, owner, duration, timing = {}) => {
      sink.notes.push({ name, volume, owner, duration, ...timing });
      return 1;
    }) satisfies AudioSink['playNote'],
    stopSequence: (name: string, letRing = false) =>
      sink.stoppedSequences.push(`${name}${letRing ? ' (let ring)' : ''}`),
    stopVoice: (voice: number) => sink.stoppedVoices.push(voice),
  };
  return sink;
}

describe('Play pattern', () => {
  it('hands the whole pattern to the player at its tempo, owned by the behavior, looping by default', () => {
    const f = playingPattern();
    const audio = recordingAudio();
    const { world, frame } = startWorld(f, { behaviors: true, audio });
    frame();
    const logic = world.entities.find((e) => e.name === 'Logic')!;
    const [asked] = audio.sequences;
    expect(asked?.name).toBe(`pattern:${f.patternId}`);
    expect(asked?.owner).toBe(logic.id);
    expect(asked?.play).toMatchObject({ tempo: 90, length: 2 * 4 * Q, loop: true });
    expect(asked?.play.sequence.notes.map((n) => [n.tick, n.note, n.instrument])).toEqual([
      [0, 60, f.lead.id],
      [Q, 64, f.lead.id],
    ]);
    expect(asked?.play.layers.length).toBe(2);
  });

  it('strikes each note through the instrument at the node’s volume, owned like the playing', () => {
    const f = playingPattern({ detached: true, loop: false });
    const audio = recordingAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    const [asked] = audio.sequences;
    expect([asked?.owner, asked?.play.loop]).toEqual(['', false]);
    asked!.play.strike({ at: 3, duration: 0.25, note: 60, velocity: 0.5, instrument: f.lead.id, tempo: 90 });
    expect(audio.notes).toEqual([
      { name: `instrument:${f.lead.id}`, volume: 0.25, owner: '', duration: 0.25, at: 3, tempo: 90 },
    ]);
  });

  it('plays nothing and hands out 0 for a pattern without an instrument', () => {
    const f = playingPattern({}, false);
    const audio = recordingAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    expect(audio.sequences).toEqual([]);
  });
});

describe('Stop pattern', () => {
  it('stops one pattern by its name, every pattern for none, and one playing by its number', () => {
    const f = playingPattern();
    const one = f.edit.addNode('StopPattern', { pattern: f.patternId, letRing: true });
    const all = f.edit.addNode('StopPattern', { pattern: '' });
    const byNumber = f.edit.addNode('StopPattern', { pattern: f.patternId });
    f.edit.connect(f.play, 'exec', one, 'exec');
    f.edit.connect(one, 'exec', all, 'exec');
    f.edit.connect(all, 'exec', byNumber, 'exec');
    f.edit.connect(f.play, 'playback', byNumber, 'playback');
    const audio = recordingAudio();
    startWorld(f, { behaviors: true, audio }).frame();
    expect(audio.stoppedSequences).toEqual([`pattern:${f.patternId} (let ring)`, '']);
    expect(audio.stoppedVoices).toEqual([1001]);
  });
});