Slack bot

slack:T04AB:U0APP
      ^team ^user

import { App } from "@slack/bolt";

const app = new App({ token: process.env.SLACK_BOT_TOKEN,
                      signingSecret: process.env.SLACK_SIGNING_SECRET });

const BASE = "https://api.usepatchwork.co/v1/loom";
const threads = new Map(); // slack thread_ts → patchwork thread id

function pw(subject) {
  return {
    "Authorization": `Bearer ${process.env.PATCHWORK_API_KEY}`,
    "Patchwork-Subject": subject,
    "Content-Type": "application/json",
  };
}

app.event("app_mention", async ({ event, say }) => {
  const subject = `slack:${event.team}:${event.user}`;
  const key = event.thread_ts ?? event.ts;
  const headers = pw(subject);

  // One Patchwork thread per Slack thread.
  let threadId = threads.get(key);
  if (!threadId) {
    const res = await fetch(`${BASE}/threads`, {
      method: "POST", headers,
      body: JSON.stringify({ agent: process.env.PATCHWORK_AGENT }),
    }).then((r) => r.json());
    threadId = res.data.id;
    threads.set(key, threadId);
  }

  const started = await fetch(`${BASE}/threads/${threadId}/messages`, {
    method: "POST", headers,
    body: JSON.stringify({ content: event.text }),
  }).then((r) => r.json());

  const reply = await settle(started.data.run_id, headers);
  await say({ text: reply, thread_ts: key });
});

async function settle(runId, headers, tries = 60) {
  for (let i = 0; i < tries; i++) {
    const { data } = await fetch(`${BASE}/runs/${runId}`, { headers })
      .then((r) => r.json());
    if (data.terminal) {
      return data.state === "failed"
        ? "Something went wrong on my side."
        : data.message?.content ?? "(no reply)";
    }
    await new Promise((r) => setTimeout(r, 1000));
  }
  return "Still working on that one.";
}