/*
 *		This file contains the javascript code for our gallery
 */

// variables for all of the templates so we only have to compile
// them once on page load and can then use the same compiled
// templates many times
var albums_template, photos_template, photo_template, slideshow_template;

// variables to store the current displayed album and photo
var current_album = gallery.albums[0];
var current_photo = current_album.photos[0];

// a helper function that instantiates a template
// and displays the results in the content div
function showTemplate(template, data) {
  var html = template(data);
  $("#content").html(html);
}

// document read gets called when the whole document
// is loaded, so we put most of the code that needs to run
// in here
$(document).ready(function () {
  //
  // compile all of our templates ready for use
  //
  var source = $("#albums-template").html();
  albums_template = Handlebars.compile(source);

  source = $("#photos-template").html();
  photos_template = Handlebars.compile(source);

  source = $("#photo-template").html();
  photo_template = Handlebars.compile(source);

  source = $("#slideshow-template").html();
  slideshow_template = Handlebars.compile(source);

  //
  //  clicking on the albums tab shows the
  //  thumbnails of all the albums
  //
  $("#albums-tab").click(function () {
    // displays the albums template
    showTemplate(albums_template, gallery);

    // make the albums tab the active one
    // first make the currently active tab inactive
    $(".nav-tabs .active").removeClass("active");
    // then make albums tab active
    $("#albums-tab").addClass("active");

    // add a click callback to each album
    // thumbnail which displays the photos
    // template on that album
    // (I have written out the code for this
    // function for clarity but it is actually
    // pretty much the same as the photos tab
    // function so we could acutally just
    // call $(".photo-thumbnail").click() )
    $(".album-thumbnail").click(function () {

      // get the index (position in the array)
      // of the album we clicked on
      // "this" is the element that was clicked on
      // data("id") gets the attribute data-id
      // (which we set to the index of the album in
      // the array - @index)
      var index = $(this).data("id");

      // set the current album to this album
      current_album = gallery.albums[index];

      // displays the photos template
      showTemplate(photos_template, current_album);

      // add an on click al all the photo thumbnails
      // which displays the photo in a modal popup
      $(".photo-thumbnail").click(function () {
        // get the index (position in the array)
        // of the photo we clicked on
        // "this" is the element that was clicked on
        // data("id") gets the attribute data-id
        // (which we set to the index of the photo in
        // the array - @index)
        var index = $(this).data("id");

        // set the current photo to this photo
        current_photo = current_album.photos[index];

        // displays the single photo template
        showTemplate(photo_template, current_photo);
      });
    });
  });

  //
  //  clicking on the photos tab shows all of the
  //  photos in the current album
  //
  $("#photos-tab").click(function () {
    // displays the photos template
    showTemplate(photos_template, current_album);

    // make the photos tab the active one
    // first make the currently active tab inactive
    $(".nav-tabs .active").removeClass("active");
    // then make photos tab active
    $("#photos-tab").addClass("active");

    // add an on click al all the photo thumbnails
    // which displays the photo in a modal popup
    $(".photo-thumbnail").click(function () {
      // get the index (position in the array)
      // of the photo we clicked on
      // "this" is the element that was clicked on
      // data("id") gets the attribute data-id
      // (which we set to the index of the photo in
      // the array - @index)
      var index = $(this).data("id");

      // set the current photo to this photo
      current_photo = current_album.photos[index];

      // displays the single photo template
      showTemplate(photo_template, current_photo);
    });
  });

  //
  //  clicking on the slideshow tab displays the
  //  current album as a slide show
  //
  $("#slideshow-tab").click(function () {
    // display the slideshow template using the
    // current album
    showTemplate(slideshow_template, current_album);

    // make the slideshow tab the active one
    // first make the currently active tab inactive
    $(".nav-tabs .active").removeClass("active");
    // then make slideshow tab active
    $("#slideshow-tab").addClass("active");
  });

  // start the page by showing the albums view
  // we do this by virtually clicking on the
  // albums tab
  $("#albums-tab").click();
});