import { ContextState, OfflineAudioContextOptions } from '../types'; import { InvalidAccessError, NotSupportedError } from '../errors'; import BaseAudioContext from './BaseAudioContext'; import AnalyserNode from './AnalyserNode'; import AudioDestinationNode from './AudioDestinationNode'; import AudioBuffer from './AudioBuffer'; import AudioBufferSourceNode from './AudioBufferSourceNode'; import BiquadFilterNode from './BiquadFilterNode'; import IIRFilterNode from './IIRFilterNode'; import GainNode from './GainNode'; import OscillatorNode from './OscillatorNode'; import PeriodicWave from './PeriodicWave'; import StereoPannerNode from './StereoPannerNode'; import ConstantSourceNode from './ConstantSourceNode'; import WaveShaperNode from './WaveShaperNode'; import ConvolverNode from './ConvolverNode'; import DelayNode from './DelayNode'; export default class OfflineAudioContext implements BaseAudioContext { readonly context: globalThis.OfflineAudioContext; readonly destination: AudioDestinationNode; readonly sampleRate: number; constructor(options: OfflineAudioContextOptions); constructor(numberOfChannels: number, length: number, sampleRate: number); constructor( arg0: OfflineAudioContextOptions | number, arg1?: number, arg2?: number ) { if (typeof arg0 === 'object') { this.context = new window.OfflineAudioContext(arg0); } else if ( typeof arg0 === 'number' && typeof arg1 === 'number' && typeof arg2 === 'number' ) { this.context = new window.OfflineAudioContext(arg0, arg1, arg2); } else { throw new NotSupportedError('Invalid constructor arguments'); } this.sampleRate = this.context.sampleRate; this.destination = new AudioDestinationNode(this, this.context.destination); } public get currentTime(): number { return this.context.currentTime; } public get state(): ContextState { return this.context.state as ContextState; } createOscillator(): OscillatorNode { return new OscillatorNode(this); } createConstantSource(): ConstantSourceNode { return new ConstantSourceNode(this); } createGain(): GainNode { return new GainNode(this); } createDelay(maxDelayTime?: number): DelayNode { return new DelayNode(this, { maxDelayTime }); } createStereoPanner(): StereoPannerNode { return new StereoPannerNode(this); } createBiquadFilter(): BiquadFilterNode { return new BiquadFilterNode(this); } createConvolver(): ConvolverNode { return new ConvolverNode(this); } createIIRFilter(feedforward: number[], feedback: number[]): IIRFilterNode { return new IIRFilterNode(this, { feedforward, feedback }); } createBufferSource(pitchCorrection?: boolean): AudioBufferSourceNode { return new AudioBufferSourceNode(this, { pitchCorrection }); } createBuffer( numberOfChannels: number, length: number, sampleRate: number ): AudioBuffer { if (numberOfChannels < 1 || numberOfChannels >= 32) { throw new NotSupportedError( `The number of channels provided (${numberOfChannels}) is outside the range [1, 32]` ); } if (length <= 0) { throw new NotSupportedError( `The number of frames provided (${length}) is less than or equal to the minimum bound (0)` ); } if (sampleRate < 8000 || sampleRate > 96000) { throw new NotSupportedError( `The sample rate provided (${sampleRate}) is outside the range [8000, 96000]` ); } return new AudioBuffer({ numberOfChannels, length, sampleRate }); } createPeriodicWave( real: Float32Array, imag: Float32Array, constraints?: PeriodicWaveConstraints ): PeriodicWave { if (real.length !== imag.length) { throw new InvalidAccessError( `The lengths of the real (${real.length}) and imaginary (${imag.length}) arrays must match.` ); } return new PeriodicWave(this, { real, imag, ...constraints }); } createAnalyser(): AnalyserNode { return new AnalyserNode(this); } createWaveShaper(): WaveShaperNode { return new WaveShaperNode(this, this.context.createWaveShaper()); } async decodeAudioDataSource(source: string): Promise { const arrayBuffer = await fetch(source).then((response) => response.arrayBuffer() ); return this.decodeAudioData(arrayBuffer); } async decodeAudioData(arrayBuffer: ArrayBuffer): Promise { return new AudioBuffer(await this.context.decodeAudioData(arrayBuffer)); } async startRendering(): Promise { return new AudioBuffer(await this.context.startRendering()); } async resume(): Promise { await this.context.resume(); } async suspend(suspendTime: number): Promise { await this.context.suspend(suspendTime); } }