// Original deterministic cue track, not a recording of ceramic or an AI provider output.
import { writeFile } from "node:fs/promises";
const sampleRate = 24000,
  duration = 6,
  total = sampleRate * duration;
const wav = Buffer.alloc(44 + total * 2);
wav.write("RIFF", 0);
wav.writeUInt32LE(36 + total * 2, 4);
wav.write("WAVEfmt ", 8);
wav.writeUInt32LE(16, 16);
wav.writeUInt16LE(1, 20);
wav.writeUInt16LE(1, 22);
wav.writeUInt32LE(sampleRate, 24);
wav.writeUInt32LE(sampleRate * 2, 28);
wav.writeUInt16LE(2, 32);
wav.writeUInt16LE(16, 34);
wav.write("data", 36);
wav.writeUInt32LE(total * 2, 40);
for (let i = 0; i < total; i++) {
  const time = i / sampleRate;
  let value = 0;
  for (const onset of [1, 3, 5]) {
    const t = time - onset;
    if (t >= 0 && t < 0.25) {
      const envelope = Math.min(1, t / 0.002) * Math.exp(-t * 35);
      value +=
        0.22 *
        envelope *
        (0.7 * Math.sin(2 * Math.PI * 720 * t) + 0.3 * Math.sin(2 * Math.PI * 1170 * t));
    }
  }
  wav.writeInt16LE(Math.round(value * 32767), 44 + i * 2);
}
await writeFile("public/blog/asmr-timing-reference.wav", wav);