import { describe, expect, it } from 'vitest';
import { newTrack } from '../../src/core/music/song';
import {
  cappedTake,
  MAX_TAKE_BYTES,
  maxTakeSamples,
  sampleCount,
  takeName,
  takeStart,
  takeTrack,
  takeTrackIndex,
  toPcm16,
  trimmedTake,
  wavBytes,
} from '../../src/core/music/take';

const pcm = (...values: number[]) => Int16Array.from(values);

describe('a recorded take (#342)', () => {
  it('turns samples into 16 bits, clipped at full scale', () => {
    expect([...toPcm16(Float32Array.from([0, 1, -1, 0.5, 2, -3]))]).toEqual([
      0, 32767, -32768, 16384, 32767, -32768,
    ]);
  });

  it('starts where the song is heard back through the input', () => {
    expect(takeStart(10, 0.02, 0.01)).toBeCloseTo(10.03, 9);
    expect(takeStart(10, -1, -1)).toBe(10);
  });

  it('drops what came before the start and cuts the chunk it falls in', () => {
    const chunks = [
      { frame: 0, samples: pcm(1, 2, 3, 4) },
      { frame: 4, samples: pcm(5, 6, 7, 8) },
      { frame: 8, samples: pcm(9, 10) },
    ];
    expect(trimmedTake(chunks, 6).map((part) => [...part])).toEqual([
      [7, 8],
      [9, 10],
    ]);
    expect(trimmedTake(chunks, 4).map((part) => [...part])).toEqual([
      [5, 6, 7, 8],
      [9, 10],
    ]);
    expect(sampleCount(trimmedTake(chunks, 0))).toBe(10);
    expect(trimmedTake(chunks, 20)).toEqual([]);
  });

  it('keeps no more than a sound may hold', () => {
    expect(cappedTake([pcm(1, 2, 3), pcm(4, 5, 6)], 4).map((part) => [...part])).toEqual([[1, 2, 3], [4]]);
    expect(maxTakeSamples() * 2 + 44).toBeLessThanOrEqual(MAX_TAKE_BYTES);
    expect(MAX_TAKE_BYTES).toBeLessThan(256 * 1024 * 1024);
  });

  it('writes a mono 16-bit PCM WAV the server knows by its RIFF header', () => {
    const bytes = wavBytes([pcm(1, -2), pcm(300)], 48000);
    const view = new DataView(bytes.buffer);
    const text = (at: number) => String.fromCharCode(...bytes.subarray(at, at + 4));
    expect(bytes.length).toBe(44 + 6);
    expect([text(0), text(8), text(12), text(36)]).toEqual(['RIFF', 'WAVE', 'fmt ', 'data']);
    expect(view.getUint32(4, true)).toBe(36 + 6);
    expect(view.getUint16(20, true)).toBe(1);
    expect(view.getUint16(22, true)).toBe(1);
    expect(view.getUint32(24, true)).toBe(48000);
    expect(view.getUint32(28, true)).toBe(96000);
    expect(view.getUint16(34, true)).toBe(16);
    expect(view.getUint32(40, true)).toBe(6);
    expect([view.getInt16(44, true), view.getInt16(46, true), view.getInt16(48, true)]).toEqual([1, -2, 300]);
  });

  it('is numbered past the takes its song keeps (#355)', () => {
    expect(takeName([])).toBe('Take 1');
    expect(takeName(['Take 1', 'Take 2', 'Intro'])).toBe('Take 3');
    expect(takeName(['Take 2'])).toBe('Take 1');
  });

  it('gets a track of its own under the one clicked last, else at the bottom', () => {
    const tracks = [newTrack(1), newTrack(2), newTrack(3)];
    expect(takeTrackIndex(tracks, tracks[0]!.id)).toBe(1);
    expect(takeTrackIndex(tracks, tracks[2]!.id)).toBe(3);
    expect(takeTrackIndex(tracks, '')).toBe(3);
    expect(takeTrack().name).toBe('Recording');
    expect(takeTrack().id).not.toBe(takeTrack().id);
  });
});