Record and Analyze a Call

const API = "https://engine.clutchcall.dev";
const KEY = process.env.CLUTCHCALL_CREDENTIALS!;
const ORG = "org_abc";

// Small tRPC caller — the audio SDK talks to these same endpoints under the hood.
async function trpc<T>(path: string, input: unknown): Promise<T> {
  const url = new URL(`/api/trpc/${path}`, API);
  url.searchParams.set("input", JSON.stringify(input));
  const res = await fetch(url, {
    headers: { authorization: `Bearer ${KEY}` },
  });
  if (!res.ok) throw new Error(`${path} ${res.status}`);
  const body = await res.json();
  return body.result.data as T;
}

// 1. list the most recent calls that have a recording
const { rows } = await trpc<{ rows: Array<{ call_id: string; duration: number }> }>(
  "cdr.recordings",
  { orgId: ORG, limit: 20 },
);

// 2. mint a 1-hour download URL for one of them
const { url, expiresIn } = await trpc<{ url: string; expiresIn: number }>(
  "storage.signedUrl",
  { orgId: ORG, callSid: rows[0].call_id },
);

console.log("download for", expiresIn, "s:", url);

// Deinterleave a 16-bit PCM stereo buffer into caller (L) and agent (R).
function splitStereoPcm16(interleaved: Int16Array) {
  const n = interleaved.length / 2;
  const caller = new Int16Array(n);
  const agent = new Int16Array(n);
  for (let i = 0; i < n; i++) {
    caller[i] = interleaved[2 * i];       // L
    agent[i] = interleaved[2 * i + 1];    // R
  }
  return { caller, agent };
}

// const wav = await (await fetch(url)).arrayBuffer();
// const pcm = new Int16Array(wav, 44);   // skip the 44-byte WAV header
// const { caller, agent } = splitStereoPcm16(pcm);
// await myAsr.transcribe(caller);   // what the caller said
// await myAsr.transcribe(agent);    // what the agent said