/*
 * Museum Gallery — XZBT Exhibit Contract 5.3 adapter.
 *
 * Same three responsibilities as every other reference exhibit's adapter
 * (declare the catalog, bind it to the real exhibit, hold no state of its
 * own) plus one addition that only this exhibit needs: declaring the
 * Contract 5.3 `surfaces` catalog (Section 31).
 *
 * This file constructs exactly ONE Exhibit State Core. It is loaded only by
 * control.html — the primary surface — which is the sole owner of the Core
 * this exhibit instance uses. artifact.html and info-wall.html never load
 * this file; they attach to the Core that control.html created, over the
 * exhibit-internal bus in surface-bus.js. See README.md for the full
 * attachment-architecture writeup.
 */
(function () {
  'use strict';

  var Core = window.XZBTContractCore;
  var Gallery = window.MuseumGalleryExhibit.Gallery;
  var ARTIFACTS = window.MuseumGalleryExhibit.ARTIFACTS;
  var ARTIFACT_LABELS = window.MuseumGalleryExhibit.ARTIFACT_LABELS;

  var IDENTITY = {
    product: 'Museum Gallery',
    version: '0.1.0',
    build: 'reference-exhibit'
  };

  var DESCRIPTORS = [
    {
      id: 'artifact.selected',
      kind: 'selection',
      label: 'Selected Artifact',
      description: 'The artifact currently on display.',
      options: ARTIFACTS.map(function (id) {
        return { value: id, label: ARTIFACT_LABELS[id] };
      }),
      readable: true, writable: true, restorable: true,
      category: 'gallery', requires: []
    },
    {
      id: 'lighting.level',
      kind: 'range',
      label: 'Lighting Level',
      description: 'Gallery lighting, 0 (dark) to 1 (full).',
      min: 0, max: 1, step: 0.01,
      readable: true, writable: true, restorable: true,
      category: 'gallery', requires: []
    },
    {
      id: 'rotation.speed',
      kind: 'range',
      label: 'Rotation Speed',
      description: 'Turntable speed under the displayed artifact.',
      min: 0, max: 2, step: 0.1,
      readable: true, writable: true, restorable: true,
      category: 'gallery', requires: []
    },
    {
      id: 'labels.enabled',
      kind: 'state',
      valueType: 'boolean',
      label: 'Labels Enabled',
      description: 'Whether descriptive labels are shown on the wall and display.',
      readable: true, writable: true, restorable: true,
      category: 'gallery', requires: []
    },
    {
      id: 'action.spotlight-flash',
      kind: 'impulse',
      label: 'Spotlight Flash',
      description: 'Briefly flash a spotlight on the current artifact.',
      readable: false, writable: false, restorable: false,
      category: 'action', requires: [], arguments: []
    }
  ];

  /* Contract 5.3 §31.2 surface descriptors. surface.control is primary. */
  var SURFACES = [
    {
      id: 'surface.control', label: 'Control Room', kind: 'surface',
      primary: true, url: 'control.html', role: 'control'
    },
    {
      id: 'surface.artifact', label: 'Artifact Display', kind: 'surface',
      primary: false, url: 'artifact.html', role: 'ambient'
    },
    {
      id: 'surface.info-wall', label: 'Information Wall', kind: 'surface',
      primary: false, url: 'info-wall.html', role: 'information'
    }
  ];

  function createMuseumGalleryContract(gallery) {
    var catalog = new Core.Catalog(DESCRIPTORS);

    var capabilities = new Core.CapabilityRegistry();
    capabilities.declare('render', 'ready');

    var surfaces = new Core.SurfaceCatalog(SURFACES);

    var setters = {
      'artifact.selected': function (v) { return gallery.setArtifact(v); },
      'lighting.level': function (v) { return gallery.setLightingLevel(v); },
      'rotation.speed': function (v) { return gallery.setRotationSpeed(v); },
      'labels.enabled': function (v) { return gallery.setLabelsEnabled(v); }
    };

    var readers = {};
    var ids = catalog.ids();
    for (var i = 0; i < ids.length; i++) {
      (function (id) {
        readers[id] = function () { return gallery.read(id); };
      })(ids[i]);
    }

    var actions = {
      'action.spotlight-flash': function () { return gallery.flashSpotlight(); }
    };

    var core = new Core.ContractCore({
      identity: IDENTITY,
      catalog: catalog,
      capabilities: capabilities,
      setters: setters,
      readers: readers,
      actions: actions,
      /* contractMinor/xzbtVersion are intentionally omitted: the shared
       * contract-core.js now defaults every exhibit to Contract 5.3, and
       * Museum Gallery has no reason to override that default. `surfaces`
       * is the one thing that makes this exhibit's contract usage different
       * from the others -- Contract 5.3 §31 presentation surfaces. */
      surfaces: surfaces
    });

    return core;
  }

  window.MuseumGalleryContract = {
    create: createMuseumGalleryContract,
    IDENTITY: IDENTITY,
    DESCRIPTORS: DESCRIPTORS,
    SURFACES: SURFACES
  };
})();