/**
 * teal.fm → Bluesky bio updater
 * Adds "Currently listening to {song} by {artists}" to your Bluesky bio
 * when a track is playing, and removes it when the status expires.
 *
 * Required secrets (wrangler secret put …):
 *   BSKY_IDENTIFIER  — your Bluesky handle or DID
 *   BSKY_PASSWORD    — your Bluesky app password
 *
 * KV binding: TEALFM_BIO_KV
 */

const STATUS_URL =
  "https://rose.madebydanny.uk/xrpc/com.atproto.repo.getRecord" +
  "?repo=YOUR_DID_HERE" +
  "&collection=fm.teal.alpha.actor.status" +
  "&rkey=self";

const BSKY_PDS = "https://rose.madebydanny.uk";

// Marker so we can reliably find and strip the now-playing line later
const NOW_PLAYING_PREFIX = "Currently listening to: ";

// KV keys
const KV_SESSION_KEY   = "bsky_session";
const KV_LAST_LINE_KEY = "bio_last_np_line"; // the exact line we injected last time

// ─── Entry point ──────────────────────────────────────────────────────────────
export default {
  // Runs every 2 minutes — adjust crons in wrangler.toml as needed
  async scheduled(event, env, ctx) {
    ctx.waitUntil(run(env));
  },

  // Manual trigger: GET /run
  async fetch(request, env, ctx) {
    const url = new URL(request.url);
    if (url.pathname === "/run") {
      ctx.waitUntil(run(env));
      return new Response("Triggered", { status: 202 });
    }
    return new Response("teal.fm bio updater", { status: 200 });
  },
};

// ─── Core logic ───────────────────────────────────────────────────────────────
async function run(env) {
  // 1. Fetch teal.fm status
  let nowPlayingLine = null; // null means "not playing"

  try {
    const res = await fetch(STATUS_URL);
    if (res.ok) {
      const body = await res.json();
      const record = body.value;
      const now    = new Date();
      const expiry = new Date(record.expiry);

      if (now <= expiry && record.item) {
        const item       = record.item;
        const artistName = item.artists.map((a) => a.artistName).join(", ");
        nowPlayingLine   = `${NOW_PLAYING_PREFIX}${item.trackName} by ${artistName}`;
      }
    }
  } catch (err) {
    console.error("Failed to fetch teal.fm status:", err);
    // Treat as not playing — safe to continue and potentially clear the bio
  }

  // 2. Auth
  let session;
  try {
    session = await getBskySession(env);
  } catch (err) {
    console.error("Bluesky auth failed:", err);
    return;
  }

  // 3. Fetch the RAW profile record so we get actual blob CID refs for
  //    avatar and banner (getProfile only returns CDN URLs, not blob refs)
  let rawRecord;
  try {
    const res = await fetch(
      `${BSKY_PDS}/xrpc/com.atproto.repo.getRecord` +
        `?repo=${encodeURIComponent(session.did)}` +
        `&collection=app.bsky.actor.profile` +
        `&rkey=self`,
      { headers: { Authorization: `Bearer ${session.accessJwt}` } }
    );
    if (!res.ok) throw new Error(`getRecord (profile) returned ${res.status}`);
    const body = await res.json();
    rawRecord = body.value;
  } catch (err) {
    console.error("Failed to fetch raw profile record:", err);
    return;
  }

  const currentBio = rawRecord.description ?? "";

  // 4. Work out what the bio should look like
  const lastLine   = await env.TEALFM_BIO_KV.get(KV_LAST_LINE_KEY);
  const updatedBio = computeNewBio(currentBio, lastLine, nowPlayingLine);

  // 5. Skip the API call if nothing changed
  if (updatedBio === currentBio) {
    console.log("Bio unchanged, skipping update.");
    return;
  }

  // 6. Push the updated profile — spread the entire raw record so every field
  //    (avatar, banner, labels, joinedViaStarterPack, etc.) is preserved exactly
  //    as-is, and only override description.
  try {
    const res = await fetch(`${BSKY_PDS}/xrpc/com.atproto.repo.putRecord`, {
      method: "POST",
      headers: {
        "Content-Type": "application/json",
        Authorization: `Bearer ${session.accessJwt}`,
      },
      body: JSON.stringify({
        repo:       session.did,
        collection: "app.bsky.actor.profile",
        rkey:       "self",
        record: {
          ...rawRecord,
          description: updatedBio,
        },
      }),
    });

    if (!res.ok) {
      const err = await res.text();
      throw new Error(`putRecord failed: ${err}`);
    }
    console.log("Bio updated:", updatedBio);
  } catch (err) {
    console.error("Failed to update profile:", err);
    return;
  }

  // 7. Persist what we injected (or clear it)
  if (nowPlayingLine) {
    await env.TEALFM_BIO_KV.put(KV_LAST_LINE_KEY, nowPlayingLine, {
      expirationTtl: 60 * 60, // auto-clean after 1 hour just in case
    });
  } else {
    await env.TEALFM_BIO_KV.delete(KV_LAST_LINE_KEY);
  }
}

// ─── Bio manipulation ─────────────────────────────────────────────────────────
/**
 * Given the current bio, the line we injected last time (if any),
 * and the new now-playing line (or null), returns the desired bio string.
 *
 * Strategy:
 *  - Strip the old now-playing line if it's present (exact match or prefix match)
 *  - Append the new now-playing line at the end, separated by a blank line
 *  - If not playing, just return the stripped bio
 */
function computeNewBio(currentBio, lastLine, nowPlayingLine) {
  let base = currentBio;

  // Remove the line we previously injected
  if (lastLine) {
    // Try exact removal (handles trailing newlines gracefully)
    base = base.replace(`\n\n${lastLine}`, "").replace(`${lastLine}\n\n`, "").replace(lastLine, "");
  }

  // Also strip any line starting with the prefix in case KV was cleared manually
  base = base
    .split("\n")
    .filter((line) => !line.startsWith(NOW_PLAYING_PREFIX))
    .join("\n")
    .trimEnd();

  if (!nowPlayingLine) return base;

  // Append the new line, with a blank line separator if there's existing bio content
  return base.length > 0 ? `${base}\n\n${nowPlayingLine}` : nowPlayingLine;
}

// ─── Bluesky session helpers ──────────────────────────────────────────────────
async function getBskySession(env) {
  const cached = await env.TEALFM_BIO_KV.get(KV_SESSION_KEY, { type: "json" });
  if (cached) {
    try {
      const check = await fetch(`${BSKY_PDS}/xrpc/com.atproto.server.getSession`, {
        headers: { Authorization: `Bearer ${cached.accessJwt}` },
      });
      if (check.ok) return cached;
    } catch {
      // Fall through to re-auth
    }
  }

  const res = await fetch(`${BSKY_PDS}/xrpc/com.atproto.server.createSession`, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify({
      identifier: env.BSKY_IDENTIFIER,
      password:   env.BSKY_PASSWORD,
    }),
  });

  if (!res.ok) {
    const err = await res.text();
    throw new Error(`createSession failed: ${err}`);
  }

  const session = await res.json();
  await env.TEALFM_BIO_KV.put(KV_SESSION_KEY, JSON.stringify(session), {
    expirationTtl: 90 * 60,
  });
  return session;
}