/*
 * Museum Gallery — Information Wall boot (non-primary surface).
 *
 * Structurally identical in principle to artifact.boot.js: no Core here,
 * only an attachment to the Control Room's Core over surface-bus.js, and a
 * clear waiting state if that Core is not reachable.
 */
(function () {
  'use strict';

  var Shell = window.XZBTShell;
  var el = Shell.el;
  var statusEl = el('status');
  var announcer = new Shell.Announcer({ node: el('announcement'), idleText: 'Waiting for shared state.' });
  var toggleButton = el('toggle-button');

  var ARTIFACT_LABELS = { 'the-orrery': 'The Orrery', 'star-map': 'Star Map', meteorite: 'Meteorite Fragment' };

  var latest = null; // read-only mirror; see artifact.boot.js for the rationale

  function render() {
    if (!latest) return;
    Shell.setText(el('artifact-name'), ARTIFACT_LABELS[latest['artifact.selected']] || latest['artifact.selected']);
    Shell.setText(el('labels-readout'), latest['labels.enabled'] ? 'Labels: ON' : 'Labels: OFF');
  }

  var link = window.MuseumGallerySurfaceBus.attach({
    timeoutMs: 1500,
    onSnapshot: function (snapshot) {
      latest = snapshot.values;
      Shell.setText(statusEl, 'Attached to Control Room.');
      statusEl.classList.remove('is-waiting');
      toggleButton.disabled = false;
      render();
    },
    onEvent: function (event) {
      if (!latest) return;
      if (event.type === 'state.changed' || event.type === 'selection.changed') {
        latest[event.target] = event.value;
        render();
      } else if (event.type === 'action.executed' && event.target === 'action.spotlight-flash') {
        announcer.flash('Spotlight flashed.');
      }
    },
    onTimeout: function () {
      Shell.setText(statusEl, 'Waiting for the Control Room surface to be open…');
      statusEl.classList.add('is-waiting');
      toggleButton.disabled = true;
    }
  });

  toggleButton.addEventListener('click', function () {
    if (!latest) return;
    /* Same canonical mutation path proof as the Artifact Display's cycle
     * button, exercising a boolean state target instead of a selection. */
    link.mutate('set', 'labels.enabled', !latest['labels.enabled']);
  });

  /* Same rationale as artifact.boot.js: `__xzbtSurfaceDispose` is the
   * deterministic path (called synchronously by local-surfaces.js right
   * before it removes this frame); `beforeunload` remains only as a
   * best-effort fallback for the cases NGN can't foresee (e.g. the tab
   * closing on its own). detach() is idempotent either way. */
  window.__xzbtSurfaceDispose = function () { link.detach(); };
  window.addEventListener('beforeunload', function () { link.detach(); });
  window.__museumGalleryDebug = { link: link };
})();