/static/js/controllers/searchresultcontroller.js

define([
  'config',
  'config/searchProviders',
  'underscore',
  'backbone',
  'lib/template',
  'lib/routecontroller',

  'models/searchcollections',
  'views/postlistview',

  'views/widgetview',
  'views/searchviews',
  'logger'
], function(
  config,
  searchProviders,
  util,
  Backbone,
  template,
  RouteController,

  searchCollections,
  PostListView,

  WidgetView,
  searchViews,
  logger
) {
  // We need to pass an empty array into empty collections that need options
  // (null gets interpreted as a value and wrapped). It's a bit fussy, but it
  // should be faster to share a single object than create one.
  var emptyArray = [];

  var SearchResultsController = RouteController.extend({
    initialize: function (options) {
      // Initialize collections object for storing search collections.
      var collections = this.collections = {};

      // > Depending on how many providers we end up with, we may want to
      // > figure out a way to lazily create collections based on what we
      // > actually need. Prototypal objects are fast, though, so it might
      // > not actually matter -GB.
      collections.bings = new searchCollections.Bing(emptyArray, {
        urlTokens: {
          base: config.searchRoot,
          path: 'bing'
        },
        urlQuery: {
          // `q: query.terms,` should be manually configured in the `enter`
          // method using `terms` method.
          format: 'json'
        }
      });

      collections.tweets = new searchCollections.Tweets(emptyArray, {
        urlTokens: {
          base: config.searchRoot,
          path: 'twitter'
        },
        urlQuery: {
          // `q: query.terms,` should be manually configured in the `enter`
          // method using `terms` method.
          format: 'json'
        }        
      });

      this.mainView = new searchViews.SearchTabsView();

      var bingListView = this.bings(collections.bings);
      var tweetListView = this.tweets(collections.tweets);

      this.mainView.widgets({
        '#bing-results': bingListView,
        '#twitter-results': tweetListView
      });

      this.mainView.bind('activate', function (view) {
        var activeView = view.widget(view.active);
        var collection = activeView.collection;
        if (collection.state() === 'invalid') {
          activeView.render();
          collection.fetchDebounced();
        }
      });

      this.mainView.activateTab('#bing-results');
    },

    enter: function (query, options) {
      util.extend(this, options || {});

      // Set this view as active in the app.
      this.appView.widget(
        '#main',
        this.mainView
      );
    },

    update: function (query, options) {
      // Update instance from options.
      // 
      // TODO: I'm not wild about the way this works -- it's too brittle -GB
      util.extend(this, options || {});

      var terms = this.parseQuery(query).terms;
      var collections = this.collections;

      // Update terms on all collections.
      for(var key in collections) collections[key].terms(terms);

      // Fetch active search collection.
      this.mainView.widget(this.mainView.active).collection.fetchDebounced();
    },

    exit: function () {
      // Empty collections on exit.
      var collections = this.collections;
      for (var key in collections) collections[key].reset();

      // These memoized collections are available as properties on the
      // bings collection.
      this.collections.bings.images().reset();
      this.collections.bings.suggestions().reset();
    },

    // Factory function for creating tweet result view with configured
    // click handlers. This is all a little bit obtuse, and could probably
    // be cleaner, but I want to avoid binding handlers in the view constructor.
    tweets: function (collection) {
      var searchTweetsView = new searchViews.SearchTweetsView({
        collection: collection
      });

      searchTweetsView.bind('visit', function (placeView, siteModel, e) {
        // TODO
      }, this);

      return searchTweetsView;
    },

    // Factory function for creating bing result view with configured
    // click handlers. This is all a little bit obtuse, and could probably
    // be cleaner, but I want to avoid binding handlers in the view constructor.
    bings: function (collection) {
      var searchBingView = new searchViews.SearchBingView({
        collection: collection
      });

      // Define a handler for `visit` events on the `searchBingView`.
      searchBingView.bind('visit', function (placeView, siteModel, e) {
        // do nothing, allow the link click to proceed
      }, this);

      // Define a handler for `suggest` events on the `searchBingView`.
      searchBingView.bind('suggest', function (view, model, e) {
        // TODO
      }, this);

      return searchBingView;
    },

    parseQuery: function (query) {
      var // parse out the query - it can be something like twitter/term1/term2
          // or just 'term'
          terms = query.split('/'),
          // a master list of search providers we support, with name: prefix.
          // define in config maybe?
          providers = searchProviders;

      var parsed = {};

      // We consider the first term to be a provider if it matches one of the
      // providers in our list.
      if(terms.length > 1 && providers[terms[0]]) {
        parsed.provider = terms.shift();
      }

      parsed.terms = terms.join(' ');
      return parsed;
    }
  });

  return new SearchResultsController();
});