'use strict';

/**
 * Band Lineup — server part.
 *
 * Owns the shared stage board and the uploaded-photo library, plus the one
 * Planning Center connection. The board is server-side and global: whoever
 * edits it (drag a library photo onto a slot, rename, clear) changes it for
 * every Band Lineup tile on every screen, over SSE. Planning Center sync is an
 * optional auto-fill — it only fills slots nobody has placed by hand. Browsers
 * never talk to Planning Center directly.
 *
 *   GET  /state              → { state }            (board + library; instant paint)
 *   GET  /stream             → SSE `state` events   (change-detected, heartbeat)
 *   GET  /library            → { people }            (the drag-in photo library)
 *   GET  /service-types      → { options }          (admin "Service type" select)
 *   GET  /plans              → { options }          (admin "Plan" select)
 *   GET  /people             → { options }          (gear "Force birthday" select)
 *   GET  /photo/<file>       → image bytes (library + cached PCO photos)
 *   POST /library/<id>       → rename / set birthday / replace photo (raw image body; ?name=&birthday=)
 *   POST /library/<id>/delete→ remove from the library and any slot
 *   POST /assign             → ?slot=&personId=  place a library person in a slot
 *   POST /move               → ?from=&to=  move or swap one slot's occupant
 *   POST /slot/<index>/name  → ?name=  rename the occupant (or make a name-only spot)
 *   POST /slot/<index>/clear → empty the slot
 *   POST /choir              → ?on=1|0  toggle the extra CHOIR slot (shared)
 *   POST /sync               → run a Planning Center + photo-folder sync now
 */

const fs = require('fs');
const path = require('path');
const os = require('os');
const crypto = require('crypto');

const { isAllowedTeamName, assignMembersToSlots, bestLibraryMatch, samePerson } = require('./matching');

const DEFAULT_API_BASE = 'https://api.planningcenteronline.com';
const API_BASE = String(process.env.BAND_LINEUP_API_BASE || process.env.PCO_PLAN_API_BASE || DEFAULT_API_BASE).replace(/\/+$/, '');
const SERVICES = '/services/v2';
const PEOPLE = '/people/v2';

const REQUEST_TIMEOUT_MS = 12000;
const PHOTO_TIMEOUT_MS = 15000;
const MIN_POLL_S = 10;
const RETRY_MS = 15000;
const HEARTBEAT_MS = 15000;
const MODULE_ID = 'band-lineup';
const MAX_UPLOAD = 20 * 1024 * 1024;

let current = null; // set by init(), read by routes; rebuilt together on remount

/* ── data directory (library + board + photo cache live here, never in the repo) ── */

function resolveDataDir() {
  const home = os.homedir();
  const fromEnv = String(process.env.PRODDASH_DATA_DIR || '').trim();
  const root = path.join(__dirname, '..', '..');
  if (fromEnv) return path.resolve(root, fromEnv);
  if (process.platform === 'win32') return path.join(process.env.APPDATA || path.join(home, 'AppData', 'Roaming'), 'ProdDash');
  if (process.platform === 'darwin') return path.join(home, 'Library', 'Application Support', 'ProdDash');
  return path.join(process.env.XDG_CONFIG_HOME || path.join(home, '.config'), 'proddash');
}

/* ── small helpers ─────────────────────────────────────────────────── */

function lines(text) { return String(text || '').split('\n').map((s) => s.trim()); }
function nonEmptyLines(text) { return lines(text).filter(Boolean); }
function localYmd(d) { return `${d.getFullYear()}-${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`; }
function birthdayMmdd(raw) {
  const s = String(raw || '').trim();
  const full = s.match(/^\d{4}-(\d{2})-(\d{2})$/);
  if (full) return `${full[1]}-${full[2]}`;
  return /^\d{2}-\d{2}$/.test(s) ? s : '';
}
function birthdayWeekSet(now = new Date()) {
  const daysSinceWed = (now.getDay() - 3 + 7) % 7;
  const start = new Date(now.getFullYear(), now.getMonth(), now.getDate() - daysSinceWed);
  const set = new Set();
  for (let i = 0; i < 7; i += 1) {
    const d = new Date(start.getFullYear(), start.getMonth(), start.getDate() + i);
    set.add(`${String(d.getMonth() + 1).padStart(2, '0')}-${String(d.getDate()).padStart(2, '0')}`);
  }
  return set;
}
function extFromContentType(ct) {
  const t = String(ct || '').toLowerCase();
  if (t.includes('png')) return 'png';
  if (t.includes('webp')) return 'webp';
  if (t.includes('gif')) return 'gif';
  return 'jpg';
}
function contentTypeForFile(file) {
  const e = path.extname(file).toLowerCase();
  if (e === '.png') return 'image/png';
  if (e === '.webp') return 'image/webp';
  if (e === '.gif') return 'image/gif';
  return 'image/jpeg';
}
function json(res, status, body) {
  res.writeHead(status, { 'Content-Type': 'application/json; charset=utf-8', 'Cache-Control': 'no-store' });
  res.end(JSON.stringify(body));
}
function readJsonFile(file, fallback) { try { return JSON.parse(fs.readFileSync(file, 'utf8')) || fallback; } catch { return fallback; } }
function newId() { return crypto.randomBytes(6).toString('hex'); }
function photoUrlFor(file) { return file ? `/api/modules/${MODULE_ID}/photo/${encodeURIComponent(file)}` : ''; }

/* ── Planning Center client ────────────────────────────────────────── */

function createPcoClient(config) {
  const token = String(config.accessToken || '').trim();
  const appId = String(config.appId || '').trim();
  const secret = String(config.secret || '');
  let auth = '';
  if (token) auth = `Bearer ${token}`;
  else if (appId && secret) auth = 'Basic ' + Buffer.from(`${appId}:${secret}`).toString('base64');
  const configured = Boolean(auth);

  async function get(target, params) {
    const url = new URL(/^https?:\/\//.test(target) ? target : API_BASE + target);
    for (const [k, v] of Object.entries(params || {})) url.searchParams.set(k, String(v));
    let response;
    try {
      response = await fetch(url, { headers: { Authorization: auth, Accept: 'application/json' }, signal: AbortSignal.timeout(REQUEST_TIMEOUT_MS) });
    } catch (err) {
      const e = new Error(`Planning Center unreachable: ${err?.message || err}`); e.network = true; throw e;
    }
    if (!response.ok) { const e = new Error(`Planning Center ${response.status}`); e.status = response.status; throw e; }
    const text = await response.text();
    return text ? JSON.parse(text) : {};
  }
  async function getAll(target, params) {
    const data = []; const included = []; let next = null;
    let query = { per_page: 100, ...(params || {}) }; let guard = 0;
    do {
      const body = next ? await get(next) : await get(target, query);
      if (Array.isArray(body.data)) data.push(...body.data);
      if (Array.isArray(body.included)) included.push(...body.included);
      next = body?.links?.next || null; query = null; guard += 1;
    } while (next && guard < 50);
    return { data, included };
  }
  return { configured, get, getAll };
}

/* ── Google Drive (public "anyone with the link" folder, no API key) ── */

const DRIVE_TIMEOUT_MS = 30000;
const DRIVE_UA = 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15) AppleWebKit/537.36';

/** Pull the folder id out of a Drive share link (or '' if it isn't a Drive folder link). */
function parseDriveFolderId(s) {
  const str = String(s || '');
  if (!/drive\.google\.com/i.test(str)) return '';
  const m = /\/folders\/([A-Za-z0-9_-]{10,})/.exec(str) || /[?&]id=([A-Za-z0-9_-]{10,})/.exec(str);
  return m ? m[1] : '';
}

/** List a public folder's files via Drive's embedded folder view — [{ id, name }]. */
async function driveList(folderId) {
  const resp = await fetch(`https://drive.google.com/embeddedfolderview?id=${encodeURIComponent(folderId)}#list`, {
    headers: { 'User-Agent': DRIVE_UA }, redirect: 'follow', signal: AbortSignal.timeout(DRIVE_TIMEOUT_MS),
  });
  if (!resp.ok) throw new Error(`Drive folder list ${resp.status}`);
  const html = await resp.text();
  const out = []; const seen = new Set();
  const re = /id="entry-([A-Za-z0-9_-]{20,})"[\s\S]*?flip-entry-title[^>]*>([^<]+)</g;
  let m;
  while ((m = re.exec(html))) {
    const id = m[1]; const name = m[2].trim();
    if (id && !seen.has(id)) { seen.add(id); out.push({ id, name }); }
  }
  return out;
}

/** Download one public Drive file at full resolution (falls back to a large thumbnail). */
async function driveFetchImage(fileId) {
  const base = 'https://drive.usercontent.google.com/download';
  const opts = { headers: { 'User-Agent': DRIVE_UA }, redirect: 'follow', signal: AbortSignal.timeout(DRIVE_TIMEOUT_MS) };
  let resp = await fetch(`${base}?id=${fileId}&export=download`, opts);
  let ct = String(resp.headers.get('content-type') || '');
  if (resp.ok && ct.startsWith('image/')) return { buf: Buffer.from(await resp.arrayBuffer()), ext: extFromContentType(ct) };
  // Large-file virus-scan interstitial: grab the confirm token and retry.
  if (ct.includes('text/html')) {
    const html = await resp.text();
    const conf = /name="confirm"\s+value="([^"]+)"/.exec(html) || /[?&]confirm=([0-9A-Za-z_-]+)/.exec(html);
    const uuid = /name="uuid"\s+value="([^"]+)"/.exec(html);
    if (conf) {
      resp = await fetch(`${base}?id=${fileId}&export=download&confirm=${conf[1]}${uuid ? `&uuid=${uuid[1]}` : ''}`, opts);
      ct = String(resp.headers.get('content-type') || '');
      if (resp.ok && ct.startsWith('image/')) return { buf: Buffer.from(await resp.arrayBuffer()), ext: extFromContentType(ct) };
    }
  }
  const th = await fetch(`https://drive.google.com/thumbnail?id=${fileId}&sz=w2000`, opts);
  const tct = String(th.headers.get('content-type') || '');
  if (th.ok && tct.startsWith('image/')) return { buf: Buffer.from(await th.arrayBuffer()), ext: extFromContentType(tct) };
  throw new Error('not an image');
}

/* ── the module ────────────────────────────────────────────────────── */

module.exports = {
  init({ config, log }) {
    const streams = new Set();
    const dataDir = path.join(resolveDataDir(), MODULE_ID);
    const photoDir = path.join(dataDir, 'photos');
    const libraryPath = path.join(dataDir, 'library.json');
    const boardPath = path.join(dataDir, 'board.json');
    try { fs.mkdirSync(photoDir, { recursive: true }); } catch (err) { log(`cannot create ${photoDir}: ${err?.message || err}`); }

    const slots = nonEmptyLines(config.slots).length ? lines(config.slots) : [];
    const teamKeywords = nonEmptyLines(config.teams).length ? nonEmptyLines(config.teams) : ['band', 'worship', 'vocal', 'production', 'communication'];
    const columns = Math.max(1, Number(config.columns) || 7);
    const serviceTypeId = String(config.serviceTypeId || '').trim();
    const planIdCfg = String(config.planId || '').trim();
    // Photos folder: the admin "Photos folder" field wins when set; otherwise it's whatever the
    // tile's "Choose folder…" picker saved into module state. Admin can't host a native picker
    // (the shell renders plain fields), so the picker lives in the tile as the no-typing option.
    const settingsPath = path.join(dataDir, 'settings.json');
    const settings = readJsonFile(settingsPath, {}) || {};
    const photoFolder = String(config.photoFolder || settings.photoFolder || '').trim(); // admin field (Drive link or local path)
    let choirOn = Boolean(settings.choir); // optional extra "CHOIR" slot, toggled from the tile
    // The photo the booth picked for a Planning Center person (PCO person id → library id), learned
    // when a library photo is dropped onto that person. Sync uses it before any name matching.
    if (!settings.photoFor || typeof settings.photoFor !== 'object') settings.photoFor = {};
    function rememberPhoto(pcoPersonId, libId) {
      if (!pcoPersonId || !libId || settings.photoFor[pcoPersonId] === libId) return;
      settings.photoFor[pcoPersonId] = libId; saveSettings();
    }
    // Library photo for a scheduled person: their remembered pick, else the best name match.
    function libraryPhotoFor(personId, name) {
      const picked = settings.photoFor[personId];
      if (picked && library[picked] && library[picked].file) return { id: picked, ...library[picked] };
      const m = bestLibraryMatch(name, Object.entries(library).map(([id, v]) => ({ id, name: v.name, file: v.file })));
      return m && m.file ? m : null;
    }
    function saveSettings() { try { fs.writeFileSync(settingsPath, JSON.stringify(settings, null, 2)); } catch (err) { log(`save settings failed: ${err?.message || err}`); } }

    const CHOIR_LABEL = 'CHOIR';
    // The board's slots plus an extra CHOIR spot when the toggle is on. Its index is slots.length,
    // so its assignment persists in board.json across toggles.
    const effectiveSlots = () => (choirOn ? slots.concat([CHOIR_LABEL]) : slots);

    const pco = createPcoClient(config);

    // Persisted, shared editor state.
    let library = readJsonFile(libraryPath, {}); // { id: { name, file, birthday } }
    let board = readJsonFile(boardPath, {});      // { slotIndex: { personId, name } }
    function saveLibrary() { try { fs.writeFileSync(libraryPath, JSON.stringify(library, null, 2)); } catch (err) { log(`save library failed: ${err?.message || err}`); } }
    function saveBoard() { try { fs.writeFileSync(boardPath, JSON.stringify(board, null, 2)); } catch (err) { log(`save board failed: ${err?.message || err}`); } }

    let latest = clearedState();
    let lastFrame = '';
    let celebrateTimer = null;
    let drivePollTimer = null;
    let watcher = null;
    let watchDebounce = null;
    let stopped = false;
    let syncing = false;

    function clearedState() {
      return {
        configured: pco.configured, serviceTypeSet: Boolean(serviceTypeId),
        reachable: false, lastError: '', lastFetched: 0, columns,
        plan: settings.lastPlan || null, // the last synced plan, so hand placements after a restart stamp right
        slots: effectiveSlots().map((label, index) => ({ index, label, person: null })),
        library: [], choir: choirOn,
      };
    }

    function libraryList() {
      return Object.entries(library)
        .map(([id, v]) => ({ id, name: v.name || '', photo: photoUrlFor(v.file || ''), birthday: v.birthday || '' }))
        .sort((a, b) => a.name.localeCompare(b.name, undefined, { sensitivity: 'base' }));
    }

    function broadcast() {
      if (!streams.size) return;
      let frame; try { frame = JSON.stringify(latest); } catch { return; }
      if (frame === lastFrame) return;
      lastFrame = frame;
      const payload = `event: state\ndata: ${frame}\n\n`;
      for (const res of streams) { try { res.write(payload); } catch { streams.delete(res); } }
    }

    async function listPlans(stId) {
      const [future, past] = await Promise.all([
        pco.get(`${SERVICES}/service_types/${encodeURIComponent(stId)}/plans`, { filter: 'future', order: 'sort_date', per_page: 6 }),
        pco.get(`${SERVICES}/service_types/${encodeURIComponent(stId)}/plans`, { filter: 'past', order: '-sort_date', per_page: 2 }),
      ]);
      const rows = [...(future.data || []), ...(past.data || [])];
      return rows.map((rec) => ({
        id: String(rec.id), sortDate: Date.parse(rec.attributes?.sort_date || '') || 0,
        title: String(rec.attributes?.title || rec.attributes?.series_title || '').trim(),
        dates: String(rec.attributes?.dates || rec.attributes?.short_dates || '').trim(),
      }));
    }
    function pickPlan(plans) {
      if (planIdCfg) return plans.find((p) => p.id === planIdCfg) || { id: planIdCfg, title: '', dates: '' };
      const todayY = localYmd(new Date());
      const today = plans.find((p) => p.sortDate && localYmd(new Date(p.sortDate)) === todayY);
      if (today) return today;
      const now = Date.now();
      const upcoming = plans.filter((p) => p.sortDate >= now - 12 * 3600000).sort((a, b) => a.sortDate - b.sortDate);
      return upcoming[0] || plans.sort((a, b) => b.sortDate - a.sortDate)[0] || null;
    }

    async function cachePcoPhoto(personId, url) {
      if (!url) return '';
      const hash = crypto.createHash('sha1').update(url).digest('hex').slice(0, 8);
      const existing = fs.existsSync(photoDir) ? fs.readdirSync(photoDir).find((f) => f.startsWith(`pco-${personId}-${hash}.`)) : null;
      if (existing) return existing;
      try {
        const resp = await fetch(url, { signal: AbortSignal.timeout(PHOTO_TIMEOUT_MS) });
        if (!resp.ok) return '';
        const buf = Buffer.from(await resp.arrayBuffer());
        if (!buf.length) return '';
        const file = `pco-${personId}-${hash}.${extFromContentType(resp.headers.get('content-type'))}`;
        fs.writeFileSync(path.join(photoDir, file), buf);
        return file;
      } catch { return ''; }
    }

    /**
     * Import a folder of photos into the library and keep it in sync: new files are added
     * (filename → name), changed files refreshed, and files removed from the folder dropped
     * from the library (and any slot they filled). Manually-uploaded photos (no folderKey) are
     * left alone, so a folder and hand-uploads can coexist. Returns true if anything changed.
     */
    const IMG_RE = /\.(jpe?g|png|webp|gif)$/i;
    const cleanNameFromFile = (f) => f.replace(/\.[^.]+$/, '').replace(/[_-]+/g, ' ').trim();
    function extOf(f) { const m = f.match(IMG_RE); const e = (m ? m[1] : 'jpg').toLowerCase(); return e === 'jpeg' ? 'jpg' : e; }
    function scanFolder() {
      if (!photoFolder) return false;
      let names; try { names = fs.readdirSync(photoFolder); } catch { return false; } // folder gone/unreadable
      const files = names.filter((n) => IMG_RE.test(n));
      const present = new Set(files);
      const byKey = new Map();
      for (const [id, v] of Object.entries(library)) if (v.folderKey) byKey.set(v.folderKey, id);
      let changed = false;
      for (const f of files) {
        let mtime = 0; try { mtime = fs.statSync(path.join(photoFolder, f)).mtimeMs; } catch { continue; }
        const id = byKey.get(f);
        try {
          if (id) {
            const v = library[id];
            if (v.mtime === mtime && v.file) continue; // unchanged
            const dest = `lib-${id}.${extOf(f)}`;
            fs.copyFileSync(path.join(photoFolder, f), path.join(photoDir, dest));
            if (v.file && v.file !== dest) { try { fs.unlinkSync(path.join(photoDir, v.file)); } catch { /* ignore */ } }
            v.file = dest; v.mtime = mtime; changed = true; // keep any in-app rename/birthday
          } else {
            const nid = newId();
            const dest = `lib-${nid}.${extOf(f)}`;
            fs.copyFileSync(path.join(photoFolder, f), path.join(photoDir, dest));
            library[nid] = { name: cleanNameFromFile(f), file: dest, birthday: '', folderKey: f, mtime };
            changed = true;
          }
        } catch (err) { log(`folder import of ${f} failed: ${err?.message || err}`); }
      }
      for (const [id, v] of Object.entries(library)) {
        if (v.folderKey && !present.has(v.folderKey)) {
          if (v.file) { try { fs.unlinkSync(path.join(photoDir, v.file)); } catch { /* ignore */ } }
          delete library[id];
          for (const [slot, b] of Object.entries(board)) if (b && b.personId === id) delete board[slot];
          changed = true;
        }
      }
      // De-duplicate: a hand-uploaded photo that shares a name with a folder photo is dropped
      // (the folder wins), and any slot it filled repoints to the folder photo. Fixes the case
      // where someone uploaded people by hand and then pointed at a folder of the same people.
      const folderByName = new Map();
      for (const [id, v] of Object.entries(library)) if (v.folderKey && v.name) folderByName.set(normName(v.name), id);
      for (const [id, v] of Object.entries(library)) {
        if (v.folderKey || !v.name) continue;
        const keepId = folderByName.get(normName(v.name));
        if (!keepId) continue;
        if (v.file) { try { fs.unlinkSync(path.join(photoDir, v.file)); } catch { /* ignore */ } }
        for (const [slot, b] of Object.entries(board)) if (b && b.personId === id) b.personId = keepId;
        delete library[id];
        changed = true;
      }
      if (changed) { saveLibrary(); saveBoard(); }
      return changed;
    }

    // Import a public Google Drive folder into the library (file name → name), keeping it in sync.
    // Keyed by Drive file id (folderKey "drive:<id>"). On a list failure we keep the last-good library.
    async function scanDrive(folderId) {
      let files;
      try { files = await driveList(folderId); } catch (err) { log(`Drive list failed: ${err?.message || err}`); return false; }
      files = files.filter((f) => IMG_RE.test(f.name));
      const present = new Set(files.map((f) => `drive:${f.id}`));
      const have = new Set();
      for (const v of Object.values(library)) if (v.folderKey && v.folderKey.startsWith('drive:')) have.add(v.folderKey);
      let changed = false;
      for (const f of files) {
        const key = `drive:${f.id}`;
        if (have.has(key)) continue; // already imported (by Drive file id)
        let img;
        try { img = await driveFetchImage(f.id); } catch (err) { log(`Drive image ${f.name} failed: ${err?.message || err}`); continue; }
        const nid = newId();
        const dest = `lib-${nid}.${img.ext}`;
        try { fs.writeFileSync(path.join(photoDir, dest), img.buf); library[nid] = { name: cleanNameFromFile(f.name), file: dest, birthday: '', folderKey: key }; changed = true; }
        catch (err) { log(`write ${dest} failed: ${err?.message || err}`); }
      }
      for (const [id, v] of Object.entries(library)) {
        if (v.folderKey && v.folderKey.startsWith('drive:') && !present.has(v.folderKey)) {
          if (v.file) { try { fs.unlinkSync(path.join(photoDir, v.file)); } catch { /* ignore */ } }
          delete library[id];
          for (const [slot, b] of Object.entries(board)) if (b && b.personId === id) delete board[slot];
          changed = true;
        }
      }
      // Drive photo wins over a same-named hand-upload (repoint any slot to it).
      const driveByName = new Map();
      for (const [id, v] of Object.entries(library)) if (v.folderKey && v.folderKey.startsWith('drive:') && v.name) driveByName.set(normName(v.name), id);
      for (const [id, v] of Object.entries(library)) {
        if ((v.folderKey && v.folderKey.startsWith('drive:')) || !v.name) continue;
        const keepId = driveByName.get(normName(v.name));
        if (!keepId) continue;
        if (v.file) { try { fs.unlinkSync(path.join(photoDir, v.file)); } catch { /* ignore */ } }
        for (const [slot, b] of Object.entries(board)) if (b && b.personId === id) b.personId = keepId;
        delete library[id]; changed = true;
      }
      if (changed) { saveLibrary(); saveBoard(); }
      return changed;
    }

    // Import the configured photo source — a Drive folder link, or a local folder path.
    async function syncPhotos() {
      const fid = parseDriveFolderId(photoFolder);
      if (fid) return scanDrive(fid);
      if (photoFolder) return scanFolder();
      return false;
    }

    function startWatch() {
      if (parseDriveFolderId(photoFolder)) return; // Drive folders are polled, not fs.watched
      if (!photoFolder) return;
      try {
        watcher = fs.watch(photoFolder, { persistent: false }, () => {
          clearTimeout(watchDebounce);
          watchDebounce = setTimeout(() => { if (!stopped && scanFolder()) rebuildLocal(); }, 800);
        });
        log(`watching photo folder ${photoFolder}`);
      } catch (err) { log(`cannot watch photo folder: ${err?.message || err}`); }
    }
    function setChoir(on) { choirOn = Boolean(on); settings.choir = choirOn; saveSettings(); rebuildLocal(); }

    // Remove cached PCO photos no longer referenced. Library files (lib-*) are never pruned here.
    function prunePcoPhotos(keep) {
      let files; try { files = fs.readdirSync(photoDir); } catch { return; }
      for (const f of files) { if (f.startsWith('pco-') && !keep.has(f)) { try { fs.unlinkSync(path.join(photoDir, f)); } catch { /* ignore */ } } }
    }

    const normName = (s) => String(s || '').trim().toLowerCase().replace(/\s+/g, ' ');

    // Resolve one board slot to a display person (or null). The board is the source of truth —
    // there is no live PCO overlay, so clearing a slot stays cleared until the next Sync. A PCO
    // entry prefers a same-named library photo, so uploading a photo updates the board without a re-sync.
    function resolveSlot(i, weekSet, keep) {
      const e = board[String(i)];
      if (!e) return null;
      let name = '', file = '', birthday = '', manual = true, personId = '';
      if (e.pco) {
        // A synced person. Their library photo (if any) is read live, so replacing that photo
        // updates the board; otherwise the photo chosen at Sync time (a PCO headshot).
        manual = false; personId = e.pco.personId || '';
        name = String(e.pco.name || '').trim();
        const lib = e.pco.libId ? library[e.pco.libId] : null;
        file = (lib && lib.file) || e.pco.file || '';
        birthday = e.pco.birthday || (lib && lib.birthday) || '';
      } else if (e.personId) {
        const lib = library[e.personId];
        if (!lib) return null; // its library photo was deleted → slot is empty
        personId = e.personId;
        name = String(e.name || lib.name || '').trim();
        file = lib.file || ''; birthday = lib.birthday || '';
      } else if (e.name) {
        name = String(e.name).trim();
      } else return null;
      if (file) keep.add(file);
      return { name, photo: photoUrlFor(file), birthday, celebrating: Boolean(birthday) && weekSet.has(birthday), manual, personId };
    }

    // Repaint the display from the board (no Planning Center calls). Cheap — used after every edit
    // and on a slow timer so a birthday week rolling over lights up on its own.
    function renderBoard() {
      const weekSet = birthdayWeekSet();
      const keep = new Set();
      const outSlots = effectiveSlots().map((label, i) => ({ index: i, label, person: resolveSlot(i, weekSet, keep) }));
      for (const v of Object.values(library)) if (v.file) keep.add(v.file);
      prunePcoPhotos(keep);
      latest = {
        configured: pco.configured, serviceTypeSet: Boolean(serviceTypeId),
        reachable: latest.reachable, lastError: latest.lastError || '', lastFetched: latest.lastFetched || 0,
        columns, plan: latest.plan || null, slots: outSlots, library: libraryList(), choir: choirOn,
      };
    }

    function rebuildLocal() { renderBoard(); broadcast(); }

    // Pull the current plan from Planning Center and write matched people INTO the board. Fills only
    // slots nobody placed by hand; drops PCO entries no longer scheduled; leaves manual placements be.
    async function syncNow() {
      if (syncing) return;
      syncing = true;
      try {
        await syncPhotos(); // import the photo source (Drive folder or local path) on every sync
        if (pco.configured && serviceTypeId) {
        const plan = pickPlan(await listPlans(serviceTypeId));
        latest.plan = plan ? { id: String(plan.id), title: plan.title, dates: plan.dates } : null;
        if (plan) { settings.lastPlan = latest.plan; saveSettings(); }
        if (!plan) { latest.reachable = true; latest.lastError = 'No plan found for that service type.'; }
        else {

        const tm = await pco.getAll(`${SERVICES}/service_types/${encodeURIComponent(serviceTypeId)}/plans/${encodeURIComponent(plan.id)}/team_members`, { include: 'person,team' });
        const byKey = new Map((tm.included || []).map((e) => [`${e.type}:${e.id}`, e]));
        const members = []; const seen = new Set();
        for (const m of tm.data || []) {
          const status = String(m.attributes?.status || '').trim();
          if (status === 'D' || /^declined$/i.test(status)) continue;
          const personId = String(m.relationships?.person?.data?.id || '');
          const team = byKey.get(`Team:${String(m.relationships?.team?.data?.id || '')}`);
          if (!isAllowedTeamName(String(team?.attributes?.name || ''), teamKeywords)) continue;
          const person = byKey.get(`Person:${personId}`);
          members.push({
            personId,
            name: String(person?.attributes?.full_name || person?.attributes?.name || m.attributes?.name || 'Unknown').trim() || 'Unknown',
            label: String(m.attributes?.team_position_name || '').trim(),
            note: String(m.attributes?.notes || '').trim(), // "Mix 8, VOX 5" — where the booth wants them this week
            photoUrl: String(person?.attributes?.photo_url || person?.attributes?.photo_thumbnail_url || '').trim(),
          });
          if (personId) seen.add(personId);
        }
        const bdays = new Map();
        for (const id of seen) { try { const b = await pco.get(`${PEOPLE}/people/${encodeURIComponent(id)}`, { 'fields[Person]': 'birthdate' }); bdays.set(id, birthdayMmdd(b?.data?.attributes?.birthdate)); } catch { bdays.set(id, ''); } }
        for (const m of members) m.birthday = bdays.get(m.personId) || '';

        // A library photo dragged by hand onto a spot for this plan, of someone who IS scheduled
        // ("Rose" for Rosaliz Gaitan): that's their photo. Remember it, and show them under their
        // Planning Center name, kept in that spot.
        for (const [i, e] of Object.entries(board)) {
          if (!e || !e.personId || e.plan !== String(plan.id) || !library[e.personId]) continue;
          const libName = library[e.personId].name;
          const who = [...new Map(members.map((m) => [m.personId, m])).values()].filter((m) => m.personId && samePerson(m.name, libName));
          if (who.length !== 1) continue; // nobody, or can't tell which — leave it a plain hand placement
          const m = who[0];
          rememberPhoto(m.personId, e.personId);
          board[i] = { pco: { name: m.name, file: library[e.personId].file, libId: e.personId, birthday: m.birthday || '', personId: m.personId }, plan: e.plan };
        }

        // Slots a person was placed in by hand FOR THIS PLAN — don't fill them, and don't place that
        // same person twice. A hand placement made for an earlier plan (last week's lineup, or one
        // from before placements were stamped) is stale: Sync replaces it like any synced slot.
        const eff = effectiveSlots();
        const planId = String(plan.id);
        const openIdx = []; const manualNames = new Set();
        for (let i = 0; i < eff.length; i += 1) {
          const e = board[String(i)];
          if (e && (e.personId || e.name || e.pco) && e.plan === planId) {
            const nm = e.pco ? e.pco.name : e.personId ? (library[e.personId] && library[e.personId].name) : e.name;
            if (nm) manualNames.add(normName(nm));
          } else openIdx.push(i);
        }
        const pool = members.filter((m) => !manualNames.has(normName(m.name)));
        const assigned = assignMembersToSlots(openIdx.map((i) => eff[i]), pool);

        for (let k = 0; k < openIdx.length; k += 1) {
          const i = openIdx[k]; const m = assigned[k];
          if (m) {
            const lib = libraryPhotoFor(m.personId, m.name); // the booth's own photos win over the PCO headshot
            const file = lib ? lib.file : await cachePcoPhoto(m.personId, m.photoUrl);
            board[String(i)] = { pco: { name: m.name, file, libId: lib ? lib.id : '', birthday: m.birthday || '', personId: m.personId } };
          } else if (board[String(i)]) {
            delete board[String(i)]; // synced or stale, and no longer on the plan
          }
        }
        saveBoard();
        latest.reachable = true; latest.lastError = ''; latest.lastFetched = Date.now();
        log(`synced ${members.length} scheduled from ${plan.dates || plan.id}`);
        } // end else (plan found)
        } // end if (Planning Center configured)
      } catch (err) {
        latest.reachable = false; latest.lastError = err?.message || String(err);
        log(`sync failed: ${err?.message || err}`);
      } finally {
        syncing = false;
        renderBoard(); broadcast();
      }
    }

    const heartbeat = setInterval(() => { for (const res of streams) { try { res.write(': ping\n\n'); } catch { streams.delete(res); } } }, HEARTBEAT_MS);
    heartbeat.unref?.();
    // Repaint on a slow timer so a birthday week (Wed→Tue) rolling over lights up unattended.
    celebrateTimer = setInterval(() => { if (!stopped) rebuildLocal(); }, 15 * 60 * 1000);
    celebrateTimer.unref?.();
    // A Drive folder can't be fs.watched — re-import it on a slow timer so photos added/removed
    // in Drive show up without a manual Sync.
    drivePollTimer = setInterval(() => {
      if (stopped || !parseDriveFolderId(photoFolder)) return;
      syncPhotos().then((ch) => { if (ch) rebuildLocal(); }).catch(() => {});
    }, 5 * 60 * 1000);
    drivePollTimer.unref?.();

    if (pco.configured && serviceTypeId) log('ready — press Sync to load the plan from Planning Center');
    else log('manual board (add Planning Center credentials + a service type in /admin to enable Sync)');
    rebuildLocal(); // paint the saved board immediately
    startWatch();   // local folders keep in sync via fs.watch (Drive folders are polled)
    syncPhotos().then((ch) => { if (ch) rebuildLocal(); }).catch((err) => log(`initial photo import failed: ${err?.message || err}`));

    current = {
      streams, getLatest: () => latest, pco, listPlans, photoDir,
      library, board, saveLibrary, saveBoard, rebuildLocal, refresh: () => syncNow(), slots,
      planId: () => (latest.plan && latest.plan.id) || '',
      rememberPhoto,
      photoUrlFor, libraryList,
      setChoir, choirOn: () => choirOn,
    };

    return {
      stop() {
        stopped = true; if (celebrateTimer) clearInterval(celebrateTimer); if (drivePollTimer) clearInterval(drivePollTimer); clearInterval(heartbeat);
        if (watcher) { try { watcher.close(); } catch { /* gone */ } watcher = null; }
        if (watchDebounce) clearTimeout(watchDebounce);
        for (const res of streams) { try { res.end(); } catch { /* gone */ } }
        streams.clear(); if (current && current.streams === streams) current = null;
      },
      health() {
        if (!pco.configured || !serviceTypeId) return { status: 'ok', message: 'Manual board (add Planning Center to enable Sync)' };
        if (latest.lastError) return { status: 'error', message: latest.lastError };
        if (latest.reachable) return { status: 'ok', message: latest.plan?.dates ? `Synced: ${latest.plan.dates}` : 'Synced' };
        return { status: 'ok', message: 'Ready — press Sync to load the plan' };
      },
    };
  },

  routes({ log }) {
    // Read an image request body (raw bytes) with a size cap.
    function readBody(req, cb) {
      const chunks = []; let size = 0; let bad = false;
      req.on('data', (c) => { size += c.length; if (size > MAX_UPLOAD) { bad = true; req.destroy(); } else chunks.push(c); });
      req.on('end', () => cb(bad ? null : Buffer.concat(chunks)));
      req.on('error', () => cb(null));
    }

    return {
      'GET /state': (req, res) => json(res, 200, { state: current ? current.getLatest() : null }),

      'GET /stream': (req, res) => {
        res.writeHead(200, { 'Content-Type': 'text/event-stream; charset=utf-8', 'Cache-Control': 'no-cache, no-transform', Connection: 'keep-alive', 'X-Accel-Buffering': 'no' });
        res.write('retry: 3000\n\n');
        res.write(`event: state\ndata: ${JSON.stringify(current ? current.getLatest() : null)}\n\n`);
        if (!current) return void res.end();
        try { req.socket.setKeepAlive(true, 15000); } catch { /* gone */ }
        current.streams.add(res);
        req.on('close', () => current && current.streams.delete(res));
      },

      'GET /library': (req, res) => json(res, 200, { people: current ? current.libraryList() : [] }),

      // Update a library entry: ?name=&birthday= and/or a replacement image body. /library/<id>/delete removes it.
      'POST /library/*': (req, res) => {
        if (!current) return json(res, 503, { error: 'Module not running.' });
        const rest = decodeURIComponent(req.wildcard || '').replace(/^\/+/, '');
        const del = /\/delete$/.test(rest);
        const id = rest.replace(/\/delete$/, '').trim();
        const entry = current.library[id];
        if (!entry) return json(res, 404, { error: 'No such library photo.' });
        if (del) {
          if (entry.file) { try { fs.unlinkSync(path.join(current.photoDir, entry.file)); } catch { /* ignore */ } }
          delete current.library[id];
          for (const [slot, v] of Object.entries(current.board)) if (v && v.personId === id) delete current.board[slot];
          current.saveLibrary(); current.saveBoard(); current.rebuildLocal();
          return json(res, 200, { ok: true });
        }
        const q = new URLSearchParams(req.search || '');
        readBody(req, (buf) => {
          if (q.has('name')) entry.name = String(q.get('name') || '').trim();
          if (q.has('birthday')) entry.birthday = birthdayMmdd(q.get('birthday'));
          if (buf && buf.length) {
            if (entry.file) { try { fs.unlinkSync(path.join(current.photoDir, entry.file)); } catch { /* ignore */ } }
            const file = `lib-${id}.${extFromContentType(req.headers['content-type'])}`;
            try { fs.writeFileSync(path.join(current.photoDir, file), buf); entry.file = file; } catch (err) { return json(res, 500, { error: `write failed: ${err?.message || err}` }); }
          }
          current.saveLibrary(); current.rebuildLocal();
          json(res, 200, { ok: true });
        });
      },

      // Toggle the extra CHOIR slot on/off (?on=1|0, or omit to flip). Shared across all screens.
      'POST /choir': (req, res) => {
        if (!current) return json(res, 503, { error: 'Module not running.' });
        const p = new URLSearchParams(req.search || '');
        const on = p.has('on') ? (p.get('on') === '1' || p.get('on') === 'true') : !current.choirOn();
        current.setChoir(on);
        json(res, 200, { ok: true, choir: on });
      },

      // Move (or swap) one slot's occupant to another slot: ?from=<i>&to=<j>.
      'POST /move': (req, res) => {
        if (!current) return json(res, 503, { error: 'Module not running.' });
        const p = new URLSearchParams(req.search || '');
        const from = String(p.get('from') || ''); const to = String(p.get('to') || '');
        if (!/^\d+$/.test(from) || !/^\d+$/.test(to) || from === to) return json(res, 400, { error: 'Bad move.' });
        const a = current.board[from]; const b = current.board[to];
        // Moving a spot is a hand placement for this plan: Sync must not move it back.
        const plan = current.planId();
        if (a) a.plan = plan;
        if (b) b.plan = plan;
        if (a === undefined) delete current.board[to]; else current.board[to] = a;
        if (b === undefined) delete current.board[from]; else current.board[from] = b;
        current.saveBoard(); current.rebuildLocal();
        json(res, 200, { ok: true });
      },

      // Place a library person in a slot: ?slot=<index>&personId=<id> (empty personId clears the slot).
      'POST /assign': (req, res) => {
        if (!current) return json(res, 503, { error: 'Module not running.' });
        const q = new URLSearchParams(req.search || '');
        const slot = String(q.get('slot') || '').trim();
        const personId = String(q.get('personId') || '').trim();
        if (!/^\d+$/.test(slot)) return json(res, 400, { error: 'Bad slot.' });
        if (personId && !current.library[personId]) return json(res, 404, { error: 'No such library photo.' });
        const here = current.board[slot];
        if (personId && here && here.pco && here.pco.personId && samePerson(here.pco.name, current.library[personId].name)) {
          // A photo of the person already in this spot: it's their photo now — this week and every
          // Sync after. They keep their Planning Center name and their spot.
          current.rememberPhoto(here.pco.personId, personId);
          current.board[slot] = { pco: { ...here.pco, libId: personId, file: current.library[personId].file }, plan: current.planId() };
        } else if (personId) current.board[slot] = { personId, name: '', plan: current.planId() };
        else delete current.board[slot];
        current.saveBoard(); current.rebuildLocal();
        json(res, 200, { ok: true });
      },

      // Rename a slot's occupant, or make a name-only spot (no photo). /slot/<index>/clear empties it.
      'POST /slot/*': (req, res) => {
        if (!current) return json(res, 503, { error: 'Module not running.' });
        const rest = decodeURIComponent(req.wildcard || '').replace(/^\/+/, '');
        const clearing = /\/clear$/.test(rest);
        const index = rest.replace(/\/(clear|name)$/, '').trim();
        if (!/^\d+$/.test(index)) return json(res, 400, { error: 'Bad slot.' });
        if (clearing) { delete current.board[index]; current.saveBoard(); current.rebuildLocal(); return json(res, 200, { ok: true }); }
        const q = new URLSearchParams(req.search || '');
        const name = String(q.get('name') || '').trim();
        const existing = current.board[index] || { personId: '', name: '' };
        existing.name = name;
        existing.plan = current.planId();
        if (!existing.personId && !name) delete current.board[index];
        else current.board[index] = existing;
        current.saveBoard(); current.rebuildLocal();
        json(res, 200, { ok: true });
      },

      // Force an immediate Planning Center refresh (the "Sync" button). Auto-fill also
      // runs on its own timer; this just does it now.
      'POST /sync': (req, res) => {
        if (!current) return json(res, 503, { error: 'Module not running.' });
        current.refresh(); // scans the photos folder + pulls the plan if Planning Center is configured
        json(res, 200, { ok: true });
      },

      'GET /people': (req, res) => {
        const state = current ? current.getLatest() : null;
        const options = [{ value: '', label: 'Off' }];
        for (const slot of state?.slots || []) if (slot.person && slot.person.name) options.push({ value: String(slot.index), label: slot.person.name });
        json(res, 200, { options });
      },

      'GET /photo/*': (req, res) => {
        if (!current) return void res.writeHead(404).end();
        const name = path.basename(decodeURIComponent(req.wildcard || '').replace(/^\/+/, ''));
        if (!name || name.includes('..')) return void res.writeHead(400).end();
        fs.readFile(path.join(current.photoDir, name), (err, buf) => {
          if (err) return void res.writeHead(404).end();
          res.writeHead(200, { 'Content-Type': contentTypeForFile(name), 'Cache-Control': 'public, max-age=60' });
          res.end(buf);
        });
      },

      'GET /service-types': async (req, res) => {
        if (!current) return json(res, 503, { options: [], error: 'Module not running.' });
        if (!current.pco.configured) return json(res, 200, { options: [], error: 'No Planning Center credentials yet.' });
        try {
          const [folderBody, stBody] = await Promise.all([current.pco.getAll(`${SERVICES}/folders`), current.pco.getAll(`${SERVICES}/service_types`)]);
          const folders = new Map();
          for (const f of folderBody.data || []) folders.set(String(f.id), { name: String(f.attributes?.name || 'Folder'), parentId: f.relationships?.parent?.data?.id ? String(f.relationships.parent.data.id) : '' });
          const pathOf = (parentId) => { const names = []; let id = parentId; const seen = new Set(); while (id && folders.has(id) && !seen.has(id)) { seen.add(id); names.unshift(folders.get(id).name); id = folders.get(id).parentId; } return names.join(' › '); };
          const options = (stBody.data || []).map((st) => ({ value: String(st.id), label: String(st.attributes?.name || 'Service type'), group: pathOf(st.relationships?.parent?.data?.id ? String(st.relationships.parent.data.id) : '') })).sort((a, b) => a.group.localeCompare(b.group) || a.label.localeCompare(b.label));
          json(res, 200, { options });
        } catch (err) { log(`service type list failed: ${err?.message || err}`); json(res, err?.status === 401 ? 401 : 502, { options: [], error: err?.message || String(err) }); }
      },

      'GET /plans': async (req, res) => {
        if (!current) return json(res, 503, { options: [] });
        const params = new URLSearchParams(req.search || '');
        const stId = String(params.get('serviceTypeId') || '').trim();
        const auto = { value: '', label: 'Automatic — today\'s plan, else the next upcoming' };
        if (!current.pco.configured || !stId) return json(res, 200, { options: [auto] });
        try {
          const plans = await current.listPlans(stId); const now = Date.now();
          const ordered = [...plans.filter((p) => p.sortDate >= now - 12 * 3600000).sort((a, b) => a.sortDate - b.sortDate), ...plans.filter((p) => p.sortDate < now - 12 * 3600000).sort((a, b) => b.sortDate - a.sortDate)];
          json(res, 200, { options: [auto, ...ordered.map((p) => ({ value: p.id, label: [p.dates, p.title].filter(Boolean).join(' — ') || p.id }))] });
        } catch (err) { json(res, 502, { options: [auto], error: err?.message || String(err) }); }
      },
    };
  },
};