import assert from 'assert';
import fs from 'fs';
import path from 'path';

import {
  LIVE_SCALE_INTERVALS,
  describeScale,
  intervalsForScaleName,
  keyDiagram,
  keysOf,
  normalizeScaleName,
  pitchClassesOf,
  resolveScale,
  sameScale,
  summarizeScale,
  toBoolean,
  toIntervals,
  toPitchClass,
  toScaleSource,
} from '../src/live';
import type { LiveScale } from '../src/live';
import { start } from '../src/max/device';
import type { Device, Lights, MaxApi } from '../src/max/device';
import { SCALES } from '../src/scale';
import type { PitchClass } from '../src/scale';

/**
 * Tests run in order on one promise chain: the device's lighting work is async,
 * so a test may need to `await device.idle()` before asserting.
 */
let passed = 0;
let chain: Promise<void> = Promise.resolve();

function test(name: string, fn: () => void | Promise<void>): void {
  chain = chain.then(async () => {
    try {
      await fn();
      passed++;
      console.log(`  ok  ${name}`);
    } catch (err) {
      console.error(`  FAIL ${name}\n       ${err instanceof Error ? err.message : err}`);
      process.exitCode = 1;
    }
  });
}

function section(name: string): void {
  chain = chain.then(() => console.log(name));
}

const REPO = path.join(__dirname, '..', '..');

section('Live scale names');

test('Live scale names resolve, however they are spelled', () => {
  assert.deepStrictEqual(intervalsForScaleName('Major'), [0, 2, 4, 5, 7, 9, 11]);
  assert.deepStrictEqual(intervalsForScaleName('major'), [0, 2, 4, 5, 7, 9, 11]);
  assert.deepStrictEqual(intervalsForScaleName('Whole Tone'), [0, 2, 4, 6, 8, 10]);
  assert.deepStrictEqual(intervalsForScaleName('whole_tone'), [0, 2, 4, 6, 8, 10]);
  assert.deepStrictEqual(intervalsForScaleName('Half-whole Dim.'), [0, 1, 3, 4, 6, 7, 9, 10]);
  assert.deepStrictEqual(intervalsForScaleName('Minor Pentatonic'), [0, 3, 5, 7, 10]);
  assert.strictEqual(intervalsForScaleName('Bebop Dominant'), null);
  assert.strictEqual(intervalsForScaleName(''), null);
});

test('aliases point at the same intervals', () => {
  assert.deepStrictEqual(intervalsForScaleName('Aeolian'), LIVE_SCALE_INTERVALS.Minor);
  assert.deepStrictEqual(intervalsForScaleName('Ionian'), LIVE_SCALE_INTERVALS.Major);
  assert.deepStrictEqual(intervalsForScaleName('Blues'), LIVE_SCALE_INTERVALS['Minor Blues']);
});

test('the fallback table agrees with the CLI presets', () => {
  assert.deepStrictEqual(intervalsForScaleName('Major'), SCALES.major);
  assert.deepStrictEqual(intervalsForScaleName('Minor'), SCALES.minor);
  assert.deepStrictEqual(intervalsForScaleName('Dorian'), SCALES.dorian);
  assert.deepStrictEqual(intervalsForScaleName('Harmonic Minor'), SCALES['harmonic-minor']);
  assert.deepStrictEqual(intervalsForScaleName('Minor Blues'), SCALES.blues);
  assert.deepStrictEqual(intervalsForScaleName('Chromatic'), SCALES.chromatic);
});

test('every scale in the table is a sane interval set', () => {
  for (const [name, intervals] of Object.entries(LIVE_SCALE_INTERVALS)) {
    assert.ok(intervals.length >= 5, `${name} is suspiciously short`);
    assert.strictEqual(intervals[0], 0, `${name} does not start on the root`);
    assert.strictEqual(new Set(intervals).size, intervals.length, `${name} has duplicates`);
    for (const i of intervals) {
      assert.ok(Number.isInteger(i) && i >= 0 && i < 12, `${name} has a bad interval ${i}`);
    }
    const ascending = [...intervals].sort((a, b) => a - b);
    assert.deepStrictEqual(intervals, ascending, `${name} is not ascending`);
  }
});

test('name normalization collapses Live punctuation', () => {
  assert.strictEqual(normalizeScaleName('  Half-whole Dim. '), 'half whole dim');
  assert.strictEqual(normalizeScaleName('Major_Pentatonic'), 'major pentatonic');
  assert.strictEqual(normalizeScaleName('Dorian #4'), 'dorian #4');
});

section('coercion of Max atoms');

test('atoms coerce the way Max sends them', () => {
  assert.strictEqual(toPitchClass(0), 0);
  assert.strictEqual(toPitchClass(7.0), 7);
  assert.strictEqual(toPitchClass('11'), 11);
  assert.strictEqual(toPitchClass('F#'), 6);
  assert.throws(() => toPitchClass(12));

  assert.deepStrictEqual(toIntervals([0, 2, 4, 5, 7, 9, 11]), [0, 2, 4, 5, 7, 9, 11]);
  assert.deepStrictEqual(toIntervals(['0', '3', '7']), [0, 3, 7]);
  assert.throws(() => toIntervals([]));

  assert.strictEqual(toBoolean(1), true);
  assert.strictEqual(toBoolean(0), false);
  assert.strictEqual(toBoolean('0'), false);
  assert.strictEqual(toBoolean('off'), false);
  assert.strictEqual(toBoolean(undefined), true);
  assert.strictEqual(toBoolean(undefined, false), false);

  assert.strictEqual(toScaleSource('song'), 'song');
  assert.strictEqual(toScaleSource('Clip'), 'clip');
  assert.throws(() => toScaleSource('track'));
});

section('resolving what Live reports');

test('intervals from Live win over the name', () => {
  const scale = resolveScale({
    root: 2,
    name: 'Major',
    // A user-edited scale in Live 12.1 keeps the name but changes the notes.
    intervals: [0, 2, 4, 5, 7, 9, 10],
    scaleMode: true,
    source: 'song',
  });
  assert.deepStrictEqual(scale.intervals, [0, 2, 4, 5, 7, 9, 10]);
});

test('a missing scale_intervals falls back to the name (pre-12.1 Live)', () => {
  const scale = resolveScale({ root: 9, name: 'Dorian' });
  assert.deepStrictEqual(scale.intervals, [0, 2, 3, 5, 7, 9, 10]);
  assert.strictEqual(scale.source, 'song');
  assert.strictEqual(scale.scaleMode, true);
});

test('unresolvable input explains itself', () => {
  assert.throws(() => resolveScale({}), /root note/);
  assert.throws(() => resolveScale({ root: 0 }), /neither/);
  assert.throws(() => resolveScale({ root: 0, name: 'Bebop' }), /not a scale we know/);
});

test('scale equality ignores nothing that matters', () => {
  const base: LiveScale = {
    root: 0,
    intervals: [0, 2, 4, 5, 7, 9, 11],
    name: 'Major',
    scaleMode: true,
    source: 'song',
  };
  assert.ok(sameScale(base, { ...base }));
  assert.ok(!sameScale(base, { ...base, root: 1 }));
  assert.ok(!sameScale(base, { ...base, source: 'clip' }));
  assert.ok(!sameScale(base, { ...base, scaleMode: false }));
  assert.ok(!sameScale(base, { ...base, intervals: [0, 2, 4, 5, 7, 9, 10] }));
  assert.ok(!sameScale(base, null));
  assert.ok(sameScale(null, null));
});

section('reporting');

test('C major from the LOM lights the home row', () => {
  const scale = resolveScale({ root: 0, name: 'Major', intervals: SCALES.major });
  assert.deepStrictEqual(pitchClassesOf(scale), [0, 2, 4, 5, 7, 9, 11]);
  assert.deepStrictEqual(keysOf(scale), ['A', 'S', 'D', 'F', 'G', 'H', 'J', 'K']);
  assert.match(summarizeScale(scale), /^C Major \(song\) — A S D F G H J K$/);
});

test('the key diagram lines up with the mapping table in the brief', () => {
  const [header, marks] = keyDiagram(pitchClassesOf(
    resolveScale({ root: 0, name: 'Major', intervals: SCALES.major })
  ));
  assert.strictEqual(header, 'A W S E D F T G Y H U J K');
  assert.strictEqual(marks, '* . * . * * . * . * . * *');
  assert.strictEqual(header.length, marks.length);
});

test('F# major marks the black keys', () => {
  const scale = resolveScale({ root: 6, name: 'Major', intervals: SCALES.major });
  assert.deepStrictEqual(keysOf(scale), ['W', 'E', 'F', 'T', 'Y', 'U', 'J']);
});

test('describeScale flags scale mode being off', () => {
  const on = describeScale(resolveScale({ root: 0, name: 'Major', scaleMode: true }));
  const off = describeScale(resolveScale({ root: 0, name: 'Major', scaleMode: false }));
  assert.ok(!on[0].includes('OFF'));
  assert.ok(off[0].includes('OFF'));
  assert.strictEqual(on.length, 6);
});

section('the Node for Max device');

interface FakeMax extends MaxApi {
  handlers: Map<string, (...args: any[]) => void>;
  posts: string[];
  outlets: unknown[][];
  send(name: string, ...args: unknown[]): void;
}

function fakeMax(): FakeMax {
  const handlers = new Map<string, (...args: any[]) => void>();
  const posts: string[] = [];
  const outlets: unknown[][] = [];
  return {
    handlers,
    posts,
    outlets,
    post: (...args: unknown[]) => posts.push(args.map((a) => String(a)).join(' ')),
    outlet: (...args: unknown[]) => outlets.push(args),
    addHandler: (name, fn) => handlers.set(name, fn),
    send(name, ...args) {
      const handler = handlers.get(name);
      if (!handler) throw new Error(`no handler for ${name}`);
      handler(...args);
    },
  };
}

/** A stand-in for ScaleLighting: records what the keyboard was asked to do. */
interface FakeLights extends Omit<Lights, 'isStarted'> {
  isStarted: boolean;
  starts: number;
  stops: number;
  frames: { root: PitchClass; intervals: readonly number[] }[];
  /** When set, every call rejects with it — a GameSense that is not there. */
  fail: string | null;
}

function fakeLights(): FakeLights {
  const lights: FakeLights = {
    isStarted: false,
    starts: 0,
    stops: 0,
    frames: [],
    fail: null,
    async start() {
      if (lights.fail) throw new Error(lights.fail);
      lights.starts++;
      lights.isStarted = true;
    },
    async showScale(root, intervals) {
      if (lights.fail) throw new Error(lights.fail);
      lights.frames.push({ root, intervals });
      return {};
    },
    async stop() {
      lights.stops++;
      lights.isStarted = false;
    },
  };
  return lights;
}

/** The device, never touching real hardware. */
function startDevice(max: FakeMax, lights: FakeLights = fakeLights()): Device {
  return start(max, { createLights: () => lights });
}

/** What max/scale-observer.js emits for one scale. */
function observe(max: FakeMax, fields: Record<string, unknown[]>): void {
  max.send('reset');
  for (const [name, args] of Object.entries(fields)) max.send(name, ...args);
  max.send('commit');
}

test('the device registers every message the observer sends', () => {
  const max = fakeMax();
  startDevice(max);
  for (const name of ['reset', 'source', 'root', 'mode', 'name', 'intervals', 'commit']) {
    assert.ok(max.handlers.has(name), `missing handler: ${name}`);
  }
  assert.ok(max.posts.some((p) => p.includes('ready')));
});

test('a burst from the observer resolves to a scale', () => {
  const max = fakeMax();
  const device = startDevice(max);
  observe(max, {
    source: ['song'],
    root: [2],
    mode: [1],
    name: ['Dorian'],
    intervals: [0, 2, 3, 5, 7, 9, 10],
  });

  assert.ok(device.scale);
  assert.strictEqual(device.scale.root, 2);
  assert.strictEqual(device.scale.name, 'Dorian');
  assert.deepStrictEqual(device.pending, {}, 'commit should clear the pending fields');

  // D dorian is the white keys, so the notes outlet is what pins the root down.
  const notes = max.outlets.find((o) => o[0] === 'notes');
  assert.deepStrictEqual(notes, ['notes', 'C', 'D', 'E', 'F', 'G', 'A', 'B']);
  const keys = max.outlets.find((o) => o[0] === 'keys');
  assert.deepStrictEqual(keys, ['keys', 'A', 'S', 'D', 'F', 'G', 'H', 'J', 'K']);
  assert.ok(max.posts.some((p) => p.includes('D Dorian')));
});

test('a multi-word scale name survives being split into atoms', () => {
  const max = fakeMax();
  const device = startDevice(max);
  observe(max, { root: [0], name: ['Whole', 'Tone'] });
  assert.strictEqual(device.scale?.name, 'Whole Tone');
  assert.deepStrictEqual(device.scale?.intervals, [0, 2, 4, 6, 8, 10]);
});

test('an unchanged scale is not re-reported, a changed one is', () => {
  const max = fakeMax();
  startDevice(max);
  const fields = { root: [0], name: ['Major'], intervals: [0, 2, 4, 5, 7, 9, 11] };

  observe(max, fields);
  const afterFirst = max.posts.length;
  observe(max, fields);
  assert.strictEqual(max.posts.length, afterFirst, 'identical scale re-printed');

  observe(max, { ...fields, root: [5] });
  assert.ok(max.posts.length > afterFirst, 'changed scale not printed');
});

test('verbose reports every commit', () => {
  const max = fakeMax();
  startDevice(max);
  const fields = { root: [0], name: ['Major'] };

  observe(max, fields);
  max.send('verbose', 1);
  const before = max.posts.length;
  observe(max, fields);
  assert.ok(max.posts.length > before);
});

test('garbage from a message box is reported, not thrown', () => {
  const max = fakeMax();
  const device = startDevice(max);

  max.send('root', 99);
  max.send('source', 'track');
  max.send('intervals', 'x');
  max.send('commit');

  assert.strictEqual(device.scale, null);
  assert.ok(max.posts.some((p) => p.includes('root:')));
  assert.ok(max.posts.some((p) => p.includes('source:')));
  assert.ok(max.posts.some((p) => p.includes('intervals:')));
  assert.ok(max.posts.some((p) => p.includes('commit:')));
});

test('status prints the current scale, or says there is none', () => {
  const max = fakeMax();
  startDevice(max);
  max.send('status');
  assert.ok(max.posts.some((p) => p.includes('no scale yet')));

  observe(max, { root: [0], name: ['Major'] });
  const before = max.posts.length;
  max.send('status');
  assert.ok(max.posts.length > before);
});

section('driving the keyboard');

const C_MAJOR = { root: [0], name: ['Major'], intervals: [0, 2, 4, 5, 7, 9, 11] };

test('a commit from Live reaches the keyboard', async () => {
  const max = fakeMax();
  const lights = fakeLights();
  const device = startDevice(max, lights);

  observe(max, { source: ['song'], root: [2], name: ['Dorian'], intervals: [0, 2, 3, 5, 7, 9, 10] });
  await device.idle();

  assert.strictEqual(lights.starts, 1, 'GameSense should be started once, lazily');
  assert.deepStrictEqual(lights.frames, [{ root: 2, intervals: [0, 2, 3, 5, 7, 9, 10] }]);
  assert.ok(max.posts.some((p) => p.includes('lighting on')));
  assert.ok(max.outlets.some((o) => o[0] === 'lighting' && o[1] === 1));
});

test('an unchanged scale is not re-sent, a changed one is', async () => {
  const max = fakeMax();
  const lights = fakeLights();
  const device = startDevice(max, lights);

  observe(max, C_MAJOR);
  observe(max, C_MAJOR);
  await device.idle();
  assert.strictEqual(lights.frames.length, 1, 'the same scale was pushed twice');
  assert.strictEqual(lights.starts, 1, 'GameSense was re-registered');

  observe(max, { ...C_MAJOR, root: [5] });
  await device.idle();
  assert.deepStrictEqual(lights.frames.map((f) => f.root), [0, 5]);
});

test('lights 0 hands the board back, lights 1 takes it again', async () => {
  const max = fakeMax();
  const lights = fakeLights();
  const device = startDevice(max, lights);

  observe(max, C_MAJOR);
  await device.idle();

  max.send('lights', 0);
  await device.idle();
  assert.strictEqual(lights.stops, 1);
  assert.strictEqual(lights.isStarted, false);
  assert.strictEqual(device.lightsEnabled, false);
  assert.ok(max.outlets.some((o) => o[0] === 'lighting' && o[1] === 0));

  // Live keeps changing scale while the lighting is off; nothing is sent...
  observe(max, { ...C_MAJOR, root: [5] });
  await device.idle();
  assert.strictEqual(lights.frames.length, 1);
  assert.ok(device.scale, 'the scale should still be tracked');

  // ...but turning it back on catches the board up with the current scale.
  max.send('lights', 1);
  await device.idle();
  assert.strictEqual(lights.starts, 2);
  assert.deepStrictEqual(lights.frames.map((f) => f.root), [0, 5]);
});

test('a GameSense failure is reported once, and retry recovers', async () => {
  const max = fakeMax();
  const lights = fakeLights();
  lights.fail = 'coreProps.json not found. Is SteelSeries GG running?';
  const device = startDevice(max, lights);

  observe(max, C_MAJOR);
  await device.idle();
  const complaints = () => max.posts.filter((p) => p.includes('coreProps.json')).length;
  assert.strictEqual(complaints(), 1);
  assert.ok(max.posts.some((p) => p.includes('retry')), 'no hint about how to recover');

  // The same failure on every commit must not fill the Max console.
  observe(max, { ...C_MAJOR, root: [5] });
  observe(max, C_MAJOR);
  await device.idle();
  assert.strictEqual(complaints(), 1);
  assert.ok(device.scale, 'a dead GameSense must not stop the device tracking Live');

  lights.fail = null;
  max.send('retry');
  await device.idle();
  assert.deepStrictEqual(lights.frames, [{ root: 0, intervals: C_MAJOR.intervals }]);
  assert.ok(max.posts.some((p) => p.includes('recovered')));
});

test('address re-points the controller and re-sends', async () => {
  const max = fakeMax();
  const lights = fakeLights();
  const addresses: (string | undefined)[] = [];
  const device = start(max, {
    createLights: (opts) => {
      addresses.push(opts.address);
      return lights;
    },
  });

  observe(max, C_MAJOR);
  await device.idle();
  max.send('address', '127.0.0.1:51000');
  await device.idle();

  assert.deepStrictEqual(addresses, [undefined, '127.0.0.1:51000']);
  assert.strictEqual(lights.stops, 1, 'the old registration should be removed');
  assert.strictEqual(lights.frames.length, 2, 'the scale should be re-sent');
});

test('shutdown blanks the board', async () => {
  const max = fakeMax();
  const lights = fakeLights();
  const device = startDevice(max, lights);

  observe(max, C_MAJOR);
  await device.idle();
  await device.shutdown();

  assert.strictEqual(lights.stops, 1);
  assert.strictEqual(lights.isStarted, false);
  assert.strictEqual(device.lights, null);
});

test('status says whether the board is being driven', async () => {
  const max = fakeMax();
  const device = startDevice(max);

  observe(max, C_MAJOR);
  await device.idle();
  max.send('status');
  assert.ok(max.posts.some((p) => p.endsWith('lighting on')));

  max.send('lights', 0);
  await device.idle();
  max.send('status');
  assert.ok(max.posts.some((p) => p.endsWith('lighting off')));
});

section('Max patcher');

test('scale-lighting.maxpat is valid JSON with the objects we wired', () => {
  const raw = fs.readFileSync(path.join(REPO, 'max', 'scale-lighting.maxpat'), 'utf8');
  const patch = JSON.parse(raw) as {
    patcher: {
      boxes: { box: { id: string; text?: string } }[];
      lines: { patchline: { source: [string, number]; destination: [string, number] } }[];
    };
  };

  const boxes = patch.patcher.boxes.map((b) => b.box);
  const texts = boxes.map((b) => b.text ?? '');
  const expectedTexts = [
    'live.thisdevice',
    'js scale-observer.js',
    'midiin',
    'midiout',
    // Step 3: the lighting controls, and blanking the board on device deletion.
    'lights 1',
    'lights 0',
    'retry',
    'closebang',
    'shutdown',
  ];
  for (const expected of expectedTexts) {
    assert.ok(texts.includes(expected), `patcher is missing ${expected}`);
  }
  assert.ok(
    texts.some((t) => t.startsWith('node.script scale-device.js')),
    'patcher is missing node.script'
  );

  // Every patch cord must point at a box that exists.
  const ids = new Set(boxes.map((b) => b.id));
  for (const { patchline } of patch.patcher.lines) {
    assert.ok(ids.has(patchline.source[0]), `dangling source ${patchline.source[0]}`);
    assert.ok(ids.has(patchline.destination[0]), `dangling destination ${patchline.destination[0]}`);
  }
});

test('the scripts the patcher names exist next to it', () => {
  for (const file of ['scale-observer.js', 'scale-device.js']) {
    assert.ok(fs.existsSync(path.join(REPO, 'max', file)), `max/${file} is missing`);
  }
});

void chain.then(() => {
  console.log(`\n${passed} passed${process.exitCode ? ', with failures' : ''}`);
});