Lofi_Generator/lib/audio/audioEngine.ts

import * as Tone from 'tone';
import { DrumMachine } from './drumMachine';
import { ChordEngine } from './chordEngine';
import { AmbientLayer } from './ambientLayer';
import { BassEngine } from './bassEngine';
import { BrassEngine } from './brassEngine';
import { PianoEngine } from './pianoEngine';
import {
  EngineState,
  AudioEngineCallbacks,
  LayerName,
  Genre,
  GENRE_CONFIG,
  DrumKit,
  BassType,
  BrassType,
  PianoType,
  ChordType,
  AmbientType,
} from '@/types/audio';

class AudioEngine {
  private static instance: AudioEngine | null = null;

  private drumMachine: DrumMachine | null = null;
  private chordEngine: ChordEngine | null = null;
  private ambientLayer: AmbientLayer | null = null;
  private bassEngine: BassEngine | null = null;
  private brassEngine: BrassEngine | null = null;
  private pianoEngine: PianoEngine | null = null;

  private masterGain: Tone.Gain | null = null;
  private masterCompressor: Tone.Compressor | null = null;
  private masterLimiter: Tone.Limiter | null = null;
  private masterReverb: Tone.Reverb | null = null;

  private callbacks: AudioEngineCallbacks = {};

  private state: EngineState = {
    isPlaying: false,
    isInitialized: false,
    bpm: 90,
    swing: 0.15,
    currentStep: 0,
    genre: 'hiphop',
    duration: 3,
    instruments: {
      drums: 'acoustic',
      bass: 'synth',
      brass: 'trumpet',
      piano: 'grand',
      chords: 'pad',
      ambient: 'rain',
    },
    volumes: {
      master: 0.8,
      drums: 0.8,
      bass: 0.6,
      brass: 0.4,
      piano: 0.5,
      chords: 0.6,
      ambient: 0.4,
    },
    muted: {
      drums: false,
      bass: false,
      brass: true,
      piano: true,
      chords: false,
      ambient: false,
    },
  };

  private constructor() {}

  static getInstance(): AudioEngine {
    if (!AudioEngine.instance) {
      AudioEngine.instance = new AudioEngine();
    }
    return AudioEngine.instance;
  }

  async initialize(): Promise<void> {
    if (this.state.isInitialized) return;

    await Tone.start();

    const genreConfig = GENRE_CONFIG[this.state.genre];
    Tone.getTransport().bpm.value = genreConfig.bpm;
    Tone.getTransport().swing = genreConfig.swing;
    Tone.getTransport().swingSubdivision = '16n';

    // Master chain
    this.masterGain = new Tone.Gain(this.state.volumes.master);
    this.masterCompressor = new Tone.Compressor({
      threshold: -20,
      ratio: 4,
      attack: 0.003,
      release: 0.25,
    });
    this.masterLimiter = new Tone.Limiter(-1);
    this.masterReverb = new Tone.Reverb({
      decay: 2,
      wet: 0.15,
    });

    this.masterGain.connect(this.masterReverb);
    this.masterReverb.connect(this.masterCompressor);
    this.masterCompressor.connect(this.masterLimiter);
    this.masterLimiter.toDestination();

    // Initialize all layers
    this.drumMachine = new DrumMachine(this.masterGain);
    this.chordEngine = new ChordEngine(this.masterGain);
    this.ambientLayer = new AmbientLayer(this.masterGain);
    this.bassEngine = new BassEngine(this.masterGain);
    this.brassEngine = new BrassEngine(this.masterGain);
    this.pianoEngine = new PianoEngine(this.masterGain);

    // Set initial genre for all engines
    this.drumMachine.setGenre(this.state.genre);
    this.chordEngine.setGenre(this.state.genre);
    this.bassEngine.setGenre(this.state.genre);
    this.brassEngine.setGenre(this.state.genre);
    this.pianoEngine.setGenre(this.state.genre);

    // Apply initial mute states
    this.brassEngine.mute(this.state.muted.brass);
    this.pianoEngine.mute(this.state.muted.piano);

    // Create sequences
    this.drumMachine.createSequence((step) => {
      this.state.currentStep = step;
      this.callbacks.onStepChange?.(step);
    });
    this.chordEngine.createSequence();
    this.bassEngine.createSequence();
    this.brassEngine.createSequence();
    this.pianoEngine.createSequence();

    this.state.bpm = genreConfig.bpm;
    this.state.swing = genreConfig.swing;
    this.state.isInitialized = true;
    this.notifyStateChange();
  }

  setCallbacks(callbacks: AudioEngineCallbacks): void {
    this.callbacks = callbacks;
  }

  private notifyStateChange(): void {
    this.callbacks.onStateChange?.({ ...this.state });
  }

  async play(): Promise<void> {
    if (!this.state.isInitialized) {
      await this.initialize();
    }

    this.ambientLayer?.start();
    Tone.getTransport().start();
    this.state.isPlaying = true;
    this.notifyStateChange();
  }

  pause(): void {
    Tone.getTransport().pause();
    this.ambientLayer?.stop();
    this.state.isPlaying = false;
    this.notifyStateChange();
  }

  stop(): void {
    Tone.getTransport().stop();
    this.ambientLayer?.stop();
    this.state.isPlaying = false;
    this.state.currentStep = 0;
    this.notifyStateChange();
  }

  generateNewBeat(): void {
    this.drumMachine?.randomize();
    this.chordEngine?.randomize();
    this.bassEngine?.randomize();
    this.brassEngine?.randomize();
    this.pianoEngine?.randomize();
    this.notifyStateChange();
  }

  setGenre(genre: Genre): void {
    this.state.genre = genre;
    const genreConfig = GENRE_CONFIG[genre];

    // Update BPM and swing for genre
    this.state.bpm = genreConfig.bpm;
    this.state.swing = genreConfig.swing;
    Tone.getTransport().bpm.value = genreConfig.bpm;
    Tone.getTransport().swing = genreConfig.swing;

    // Update all engines with new genre
    this.drumMachine?.setGenre(genre);
    this.chordEngine?.setGenre(genre);
    this.bassEngine?.setGenre(genre);
    this.brassEngine?.setGenre(genre);
    this.pianoEngine?.setGenre(genre);

    this.notifyStateChange();
  }

  setDuration(minutes: number): void {
    this.state.duration = Math.max(1, Math.min(10, minutes));
    this.notifyStateChange();
  }

  setInstrument(layer: LayerName, instrument: string): void {
    switch (layer) {
      case 'drums':
        this.state.instruments.drums = instrument as DrumKit;
        this.drumMachine?.setInstrument(instrument as DrumKit);
        break;
      case 'bass':
        this.state.instruments.bass = instrument as BassType;
        this.bassEngine?.setInstrument(instrument as BassType);
        break;
      case 'brass':
        this.state.instruments.brass = instrument as BrassType;
        this.brassEngine?.setInstrument(instrument as BrassType);
        break;
      case 'piano':
        this.state.instruments.piano = instrument as PianoType;
        this.pianoEngine?.setInstrument(instrument as PianoType);
        break;
      case 'chords':
        this.state.instruments.chords = instrument as ChordType;
        this.chordEngine?.setInstrument(instrument as ChordType);
        break;
      case 'ambient':
        this.state.instruments.ambient = instrument as AmbientType;
        this.ambientLayer?.setInstrument(instrument as AmbientType);
        break;
    }
    this.notifyStateChange();
  }

  setBpm(bpm: number): void {
    this.state.bpm = Math.max(60, Math.min(180, bpm));
    Tone.getTransport().bpm.value = this.state.bpm;
    this.notifyStateChange();
  }

  setSwing(swing: number): void {
    this.state.swing = Math.max(0, Math.min(0.5, swing));
    Tone.getTransport().swing = this.state.swing;
    this.notifyStateChange();
  }

  setMasterVolume(volume: number): void {
    this.state.volumes.master = Math.max(0, Math.min(1, volume));
    this.masterGain?.gain.rampTo(this.state.volumes.master, 0.1);
    this.notifyStateChange();
  }

  setLayerVolume(layer: LayerName, volume: number): void {
    const normalizedVolume = Math.max(0, Math.min(1, volume));
    this.state.volumes[layer] = normalizedVolume;

    switch (layer) {
      case 'drums':
        this.drumMachine?.setVolume(normalizedVolume);
        break;
      case 'bass':
        this.bassEngine?.setVolume(normalizedVolume);
        break;
      case 'brass':
        this.brassEngine?.setVolume(normalizedVolume);
        break;
      case 'piano':
        this.pianoEngine?.setVolume(normalizedVolume);
        break;
      case 'chords':
        this.chordEngine?.setVolume(normalizedVolume);
        break;
      case 'ambient':
        this.ambientLayer?.setVolume(normalizedVolume);
        break;
    }

    this.notifyStateChange();
  }

  toggleMute(layer: LayerName): void {
    this.state.muted[layer] = !this.state.muted[layer];

    switch (layer) {
      case 'drums':
        this.drumMachine?.mute(this.state.muted[layer]);
        break;
      case 'bass':
        this.bassEngine?.mute(this.state.muted[layer]);
        break;
      case 'brass':
        this.brassEngine?.mute(this.state.muted[layer]);
        break;
      case 'piano':
        this.pianoEngine?.mute(this.state.muted[layer]);
        break;
      case 'chords':
        this.chordEngine?.mute(this.state.muted[layer]);
        break;
      case 'ambient':
        this.ambientLayer?.mute(this.state.muted[layer]);
        break;
    }

    this.notifyStateChange();
  }

  setMuted(layer: LayerName, muted: boolean): void {
    this.state.muted[layer] = muted;

    switch (layer) {
      case 'drums':
        this.drumMachine?.mute(muted);
        break;
      case 'bass':
        this.bassEngine?.mute(muted);
        break;
      case 'brass':
        this.brassEngine?.mute(muted);
        break;
      case 'piano':
        this.pianoEngine?.mute(muted);
        break;
      case 'chords':
        this.chordEngine?.mute(muted);
        break;
      case 'ambient':
        this.ambientLayer?.mute(muted);
        break;
    }

    this.notifyStateChange();
  }

  getState(): EngineState {
    return { ...this.state };
  }

  dispose(): void {
    this.stop();
    this.drumMachine?.dispose();
    this.chordEngine?.dispose();
    this.ambientLayer?.dispose();
    this.bassEngine?.dispose();
    this.brassEngine?.dispose();
    this.pianoEngine?.dispose();
    this.masterGain?.dispose();
    this.masterCompressor?.dispose();
    this.masterLimiter?.dispose();
    this.masterReverb?.dispose();

    this.drumMachine = null;
    this.chordEngine = null;
    this.ambientLayer = null;
    this.bassEngine = null;
    this.brassEngine = null;
    this.pianoEngine = null;
    this.masterGain = null;
    this.masterCompressor = null;
    this.masterLimiter = null;
    this.masterReverb = null;

    this.state.isInitialized = false;
    this.state.isPlaying = false;
    AudioEngine.instance = null;
  }
}

export const audioEngine = AudioEngine.getInstance();
export default audioEngine;