temporary

src/lib/bytebeat/BytebeatGenerator.ts

@@ -0,0 +1,154 @@
+import type { BytebeatOptions, BitDepth } from './types'
+import { encodeWAV } from './wavEncoder'
+import { EffectsChain } from './EffectsChain'
+import type { EffectValues } from '../../types/effects'
+
+export class BytebeatGenerator {
+  private sampleRate: number
+  private duration: number
+  private formula: string | null = null
+  private compiledFormula: ((t: number) => number) | null = null
+  private audioBuffer: Float32Array | null = null
+  private audioContext: AudioContext | null = null
+  private sourceNode: AudioBufferSourceNode | null = null
+  private effectsChain: EffectsChain | null = null
+  private effectValues: EffectValues = {}
+  private startTime: number = 0
+  private pauseTime: number = 0
+  private isLooping: boolean = true
+
+  constructor(options: BytebeatOptions = {}) {
+    this.sampleRate = options.sampleRate ?? 8000
+    this.duration = options.duration ?? 10
+  }
+
+  setFormula(formula: string): void {
+    this.formula = formula
+    try {
+      this.compiledFormula = new Function('t', `return ${formula}`) as (t: number) => number
+      this.audioBuffer = null
+    } catch (error) {
+      throw new Error(`Invalid formula: ${error instanceof Error ? error.message : 'Unknown error'}`)
+    }
+  }
+
+  generate(): Float32Array {
+    if (!this.compiledFormula) {
+      throw new Error('No formula set. Call setFormula() first.')
+    }
+
+    const numSamples = Math.floor(this.sampleRate * this.duration)
+    const buffer = new Float32Array(numSamples)
+
+    for (let t = 0; t < numSamples; t++) {
+      try {
+        const value = this.compiledFormula(t)
+        const byteValue = value & 0xFF
+        buffer[t] = (byteValue - 128) / 128
+      } catch (error) {
+        buffer[t] = 0
+      }
+    }
+
+    this.audioBuffer = buffer
+    return buffer
+  }
+
+  setEffects(values: EffectValues): void {
+    this.effectValues = values
+    if (this.effectsChain) {
+      this.effectsChain.updateEffects(values)
+    }
+  }
+
+  getPlaybackPosition(): number {
+    if (!this.audioContext || !this.sourceNode || this.startTime === 0) {
+      return 0
+    }
+    const elapsed = this.audioContext.currentTime - this.startTime
+    return (elapsed % this.duration) / this.duration
+  }
+
+  play(): void {
+    if (!this.audioBuffer) {
+      this.generate()
+    }
+
+    if (!this.audioContext) {
+      this.audioContext = new AudioContext({ sampleRate: this.sampleRate })
+    }
+
+    if (!this.effectsChain) {
+      this.effectsChain = new EffectsChain(this.audioContext)
+      this.effectsChain.updateEffects(this.effectValues)
+    }
+
+    if (this.sourceNode) {
+      this.sourceNode.stop()
+    }
+
+    const audioBuffer = this.audioContext.createBuffer(1, this.audioBuffer!.length, this.sampleRate)
+    audioBuffer.getChannelData(0).set(this.audioBuffer!)
+
+    this.sourceNode = this.audioContext.createBufferSource()
+    this.sourceNode.buffer = audioBuffer
+    this.sourceNode.loop = this.isLooping
+    this.sourceNode.connect(this.effectsChain.getInputNode())
+    this.effectsChain.getOutputNode().connect(this.audioContext.destination)
+
+    if (this.pauseTime > 0) {
+      this.sourceNode.start(0, this.pauseTime)
+      this.startTime = this.audioContext.currentTime - this.pauseTime
+      this.pauseTime = 0
+    } else {
+      this.sourceNode.start(0)
+      this.startTime = this.audioContext.currentTime
+    }
+  }
+
+  pause(): void {
+    if (this.sourceNode && this.audioContext) {
+      this.pauseTime = this.audioContext.currentTime - this.startTime
+      this.sourceNode.stop()
+      this.sourceNode = null
+    }
+  }
+
+  stop(): void {
+    if (this.sourceNode) {
+      this.sourceNode.stop()
+      this.sourceNode = null
+    }
+    this.startTime = 0
+    this.pauseTime = 0
+  }
+
+  exportWAV(bitDepth: BitDepth = 8): Blob {
+    if (!this.audioBuffer) {
+      this.generate()
+    }
+    return encodeWAV(this.audioBuffer!, this.sampleRate, bitDepth)
+  }
+
+  downloadWAV(filename: string = 'bytebeat.wav', bitDepth: BitDepth = 8): void {
+    const blob = this.exportWAV(bitDepth)
+    const url = URL.createObjectURL(blob)
+    const a = document.createElement('a')
+    a.href = url
+    a.download = filename
+    a.click()
+    URL.revokeObjectURL(url)
+  }
+
+  dispose(): void {
+    this.stop()
+    if (this.effectsChain) {
+      this.effectsChain.dispose()
+      this.effectsChain = null
+    }
+    if (this.audioContext) {
+      this.audioContext.close()
+      this.audioContext = null
+    }
+  }
+}