import { InvalidAccessError, NotSupportedError } from '../errors'; import { AudioContextOptions, ContextState, DecodeDataInput } from '../types'; import AnalyserNode from './AnalyserNode'; import AudioBuffer from './AudioBuffer'; import AudioBufferSourceNode from './AudioBufferSourceNode'; import AudioDestinationNode from './AudioDestinationNode'; import BaseAudioContext from './BaseAudioContext'; import BiquadFilterNode from './BiquadFilterNode'; import ConvolverNode from './ConvolverNode'; import DelayNode from './DelayNode'; import GainNode from './GainNode'; import IIRFilterNode from './IIRFilterNode'; import OscillatorNode from './OscillatorNode'; import PeriodicWave from './PeriodicWave'; import StereoPannerNode from './StereoPannerNode'; import ConstantSourceNode from './ConstantSourceNode'; import WaveShaperNode from './WaveShaperNode'; export default class AudioContext implements BaseAudioContext { readonly context: globalThis.AudioContext; readonly destination: AudioDestinationNode; readonly sampleRate: number; constructor(options?: AudioContextOptions) { if ( options && options.sampleRate && (options.sampleRate < 8000 || options.sampleRate > 96000) ) { throw new NotSupportedError( `The provided sampleRate is not supported: ${options.sampleRate}` ); } this.context = new window.AudioContext({ sampleRate: options?.sampleRate }); this.sampleRate = this.context.sampleRate; this.destination = new AudioDestinationNode(this, this.context.destination); } public get currentTime(): number { return this.context.currentTime; } public get state(): ContextState { return this.context.state as ContextState; } createOscillator(): OscillatorNode { return new OscillatorNode(this); } createConstantSource(): ConstantSourceNode { return new ConstantSourceNode(this); } createGain(): GainNode { return new GainNode(this); } createDelay(maxDelayTime?: number): DelayNode { return new DelayNode(this, { maxDelayTime }); } createStereoPanner(): StereoPannerNode { return new StereoPannerNode(this); } createBiquadFilter(): BiquadFilterNode { return new BiquadFilterNode(this); } createConvolver(): ConvolverNode { return new ConvolverNode(this); } createIIRFilter(feedforward: number[], feedback: number[]): IIRFilterNode { return new IIRFilterNode(this, { feedforward, feedback }); } createBufferSource(pitchCorrection?: boolean): AudioBufferSourceNode { return new AudioBufferSourceNode(this, { pitchCorrection }); } createBuffer( numberOfChannels: number, length: number, sampleRate: number ): AudioBuffer { if (numberOfChannels < 1 || numberOfChannels >= 32) { throw new NotSupportedError( `The number of channels provided (${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 decodeAudioData( source: DecodeDataInput, fetchOptions?: RequestInit ): Promise { if (source instanceof ArrayBuffer) { const decodedData = await this.context.decodeAudioData(source); return new AudioBuffer(decodedData); } if (typeof source === 'string') { const response = await fetch(source, fetchOptions); if (!response.ok) { throw new InvalidAccessError( `Failed to fetch audio data from the provided source: ${source}` ); } const arrayBuffer = await response.arrayBuffer(); const decodedData = await this.context.decodeAudioData(arrayBuffer); return new AudioBuffer(decodedData); } throw new TypeError('Unsupported source for decodeAudioData: ' + source); } async close(): Promise { await this.context.close(); } async resume(): Promise { await this.context.resume(); } async suspend(): Promise { await this.context.suspend(); } }