$(function() {
  var qs = recline.View.parseQueryString(window.location.search);
  if (qs.url) {
    var dataset = new recline.Model.Dataset({
        id: 'my-dataset',
        url: qs.url,
        webstore_url: qs.url 
      },
      qs.backend || 'elasticsearch'
    );
  } else {
    dataset = localDataset();
  }

  createExplorer(dataset);
  Backbone.history.start();

  // setup the loader menu in top bar
  setupLoader(createExplorer);

  // set up readonly enabling in top bar
  $('a.set-read-only').click(function() {
    window.dataExplorer.setReadOnly();
    alert('Read-only mode set');
  });
});

// make Explorer creation / initialization in a function so we can call it
// again and again
function createExplorer(dataset) {
  // remove existing data explorer view
  var reload = false;
  if (window.dataExplorer) {
    window.dataExplorer.remove();
    reload = true;
  }
  window.dataExplorer = null;
  var $el = $('<div />');
  $el.appendTo($('.data-explorer-here'));
  var views = standardViews(dataset);
  window.dataExplorer = new recline.View.DataExplorer({
    el: $el
    , model: dataset
    , views: views
  });
  // HACK (a bit). Issue is that Backbone will not trigger the route
  // if you are already at that location so we have to make sure we genuinely switch
  if (reload) {
    window.dataExplorer.router.navigate('graph');
    window.dataExplorer.router.navigate('', true);
  }
}

// convenience function
function standardViews(dataset) {
  var views = [
    {
      id: 'grid',
      label: 'Grid',
      view: new recline.View.DataGrid({
        model: dataset
      })
    },
    {
      id: 'graph',
      label: 'Graph',
      view: new recline.View.FlotGraph({
        model: dataset
      })
    }
  ];
  return views;
}

// provide a demonstration in memory dataset
function localDataset() {
  var datasetId = 'test-dataset';
  var inData = {
    metadata: {
      title: 'My Test Dataset'
      , name: '1-my-test-dataset' 
      , id: datasetId
    },
    fields: [{id: 'x'}, {id: 'y'}, {id: 'z'}, {id: 'label'}],
    documents: [
      {id: 0, x: 1, y: 2, z: 3, label: 'first'}
      , {id: 1, x: 2, y: 4, z: 6, label: 'second'}
      , {id: 2, x: 3, y: 6, z: 9, label: 'third'}
      , {id: 3, x: 4, y: 8, z: 12, label: 'fourth'}
      , {id: 4, x: 5, y: 10, z: 15, label: 'fifth'}
      , {id: 5, x: 6, y: 12, z: 18, label: 'sixth'}
    ]
  };
  var backend = new recline.Backend.Memory();
  backend.addDataset(inData);
  var dataset = new recline.Model.Dataset({id: datasetId}, backend);
  return dataset;
}

// setup the loader menu in top bar
function setupLoader(callback) {
  // pre-populate webstore load form with an example url
  var demoUrl = 'http://thedatahub.org/api/data/b9aae52b-b082-4159-b46f-7bb9c158d013';
  $('form.webstore-load input[name="source"]').val(demoUrl);
  $('form.webstore-load').submit(function(e) {
    e.preventDefault();
    var $form = $(e.target);
    var source = $form.find('input[name="source"]').val();
    var type = $form.find('select[name="backend_type"]').val();
    var dataset = new recline.Model.Dataset({
        id: 'my-dataset',
        url: source,
        webstore_url: source
      },
      type
    );
    callback(dataset);
  });
}