/**
 * Galleria (http://monc.se/kitchen)
 *
 * Galleria is a javascript image gallery written in jQuery. 
 * It loads the images one by one from an unordered list and displays thumbnails when each image is loaded. 
 * It will create thumbnails for you if you choose so, scaled or unscaled, 
 * centered and cropped inside a fixed thumbnail box defined by CSS.
 * 
 * The core of Galleria lies in it's smart preloading behaviour, snappiness and the fresh absence 
 * of obtrusive design elements. Use it as a foundation for your custom styled image gallery.
 *
 * MAJOR CHANGES v.FROM 0.9
 * Galleria now features a useful history extension, enabling back button and bookmarking for each image.
 * The main image is no longer stored inside each list item, instead it is placed inside a container
 * onImage and onThumb functions lets you customize the behaviours of the images on the site
 *
 * Tested in Safari 3, Firefox 2, MSIE 6, MSIE 7, Opera 9
 * 
 * Version 1.0
 * Februari 21, 2008
 *
 * Copyright (c) 2008 David Hellsing (http://monc.se)
 * Licensed under the GPL licenses.
 * http://www.gnu.org/licenses/gpl.txt
 **/

(function($){

var $$;


/**
 * 
 * @desc Convert images from a simple html <ul> into a thumbnail gallery
 * @author David Hellsing
 * @version 1.0
 *
 * @name Galleria
 * @type jQuery
 *
 * @cat plugins/Media
 * 
 * @example $('ul.gallery').galleria({options});
 * @desc Create a a gallery from an unordered list of images with thumbnails
 * @options
 *   insert:   (selector string) by default, Galleria will create a container div before your ul that holds the image.
 *             You can, however, specify a selector where the image will be placed instead (f.ex '#main_img')
 *   history:  Boolean for setting the history object in action with enabled back button, bookmarking etc.
 *   onImage:  (function) a function that gets fired when the image is displayed and brings the jQuery image object.
 *             You can use it to add click functionality and effects.
 *             f.ex onImage(image) { image.css('display','none').fadeIn(); } will fadeIn each image that is displayed
 *   onThumb:  (function) a function that gets fired when the thumbnail is displayed and brings the jQuery thumb object.
 *             Works the same as onImage except it targets the thumbnail after it's loaded.
 *
**/

$$ = $.fn.galleria = function($options) {
  
  // check for basic CSS support
  if (!$$.hasCSS()) { return false; }
  
  // init the modified history object
  $.historyInit($$.onPageLoad);
  
  // set default options
  var $defaults = {
    insert      : '.galleria_container',
    history     : true,
    clickNext   : true,
    onImage     : function(image,caption,thumb) {},
    onThumb     : function(thumb) {}
  };
  

  // extend the options
  var $opts = $.extend($defaults, $options);

  // bring the options to the galleria object
  for (var i in $opts) {
    if (i) {
      $.galleria[i]  = $opts[i];
    }
  }

  // if no insert selector, create a new division and insert it before the ul
  var _insert = ( $($opts.insert).is($opts.insert) ) ? 
    $($opts.insert) : 
    jQuery(document.createElement('div')).insertBefore(this);

  // create a wrapping div for the image
  var _div = $(document.createElement('div')).addClass('galleria_wrapper');

  // create a caption span
  var _span = $(document.createElement('span')).addClass('caption');
  var _desc = $(document.createElement('span')).addClass('description');

  // inject the wrapper in in the insert selector
  _insert.addClass('galleria_container').append(_div).append(_span).append(_desc);

  //-------------

  return this.each(function(){

    // add the Galleria class
    $(this).addClass('galleria');

    // loop through list
    $(this).children('li').each(function(i) {

      // bring the scope
      var _container = $(this);

      // build element specific options
      var _o = $.meta ? $.extend({}, $opts, _container.data()) : $opts;

      // remove the clickNext if image is only child
      _o.clickNext = $(this).is(':only-child') ? false : _o.clickNext;

      // try to fetch an anchor
      var _a = $(this).find('a').is('a') ? $(this).find('a') : false;

      // reference the original image as a variable and hide it
      var _img = $(this).children('img').css('display','none');

      // extract the original source
      var _src = _a ? _a.attr('href') : _img.attr('src');

      // find a title
      var _title = _a ? _a.attr('title') : _img.attr('title');

      var _description = _img.attr('description');

      // create loader image
      var _loader = new Image();

      // check url and activate container if match
      if (_o.history && (window.location.hash && window.location.hash.replace(/\#/,'') == _src)) {
        _container.siblings('.active').removeClass('active');
        _container.addClass('active');
      }

      // begin loader
      $(_loader).load(function () {

        // try to bring the alt
        $(this).attr('alt',_img.attr('alt'));

        //-----------------------------------------------------------------
        // the image is loaded, let's create the thumbnail

        var _thumb = _a ?
          _a.find('img').addClass('thumb noscale').css('display','none') :
          _img.clone(true).addClass('thumb').css('display','none');

        if (_a) { _a.replaceWith(_thumb); }

        if (!_thumb.hasClass('noscale')) { // scaled tumbnails!
          var w = Math.ceil( _img.width() / _img.height() * _container.height() );
          var h = Math.ceil( _img.height() / _img.width() * _container.width() );
          if (w < h) {
            _thumb.css({ height: 'auto', width: _container.width(), marginTop: -(h-_container.height())/2 });
          } else {
            _thumb.css({ width: 'auto', height: _container.height(), marginLeft: -(w-_container.width())/2 });
          }
        } else { // Center thumbnails.
          // a tiny timer fixed the width/height
          window.setTimeout(function() {
            _thumb.css({
              marginLeft: -( _thumb.width() - _container.width() )/2, 
              marginTop:  -( _thumb.height() - _container.height() )/2
            });
          }, 1);
        }

        // add the rel attribute
        _thumb.attr('rel',_src);

        // add the title attribute
        _thumb.attr('title',_title);
        _thumb.attr('description',_description);

        // add the click functionality to the _thumb
        _thumb.click(function() {
          $.galleria.activate(_src);
        });

        // hover classes for IE6
        _thumb.hover(
          function() { $(this).addClass('hover'); },
          function() { $(this).removeClass('hover'); }
        );
        _container.hover(
          function() { _container.addClass('hover'); },
          function() { _container.removeClass('hover'); }
        );

        // prepend the thumbnail in the container
        _container.prepend(_thumb);

        // show the thumbnail
        _thumb.css('display','block');

        // call the onThumb function
        _o.onThumb(jQuery(_thumb));

        // check active class and activate image if match
        if (_container.hasClass('active')) {
          $.galleria.activate(_src);
          //_span.text(_title);
        }

        //-----------------------------------------------------------------

        // finally delete the original image
        _img.remove();

      }).error(function () {

        // Error handling
          _container.html('<span class="error" style="color:red">Error loading image: '+_src+'</span>');

      }).attr('src', _src);
    });
  });
};

/**
 *
 * @name NextSelector
 *
 * @desc Returns the sibling sibling, or the first one
 *
**/

$$.nextSelector = function(selector) {
  return $(selector).is(':last-child') ?
       $(selector).siblings(':first-child') :
         $(selector).next();

};

/**
 *
 * @name previousSelector
 *
 * @desc Returns the previous sibling, or the last one
 *
**/

$$.previousSelector = function(selector) {
  return $(selector).is(':first-child') ?
       $(selector).siblings(':last-child') :
         $(selector).prev();

};

/**
 *
 * @name hasCSS
 *
 * @desc Checks for CSS support and returns a boolean value
 *
**/

$$.hasCSS = function()  {
  $('body').append(
    $(document.createElement('div')).attr('id','css_test').css({ width:'1px', height:'1px', display:'none' })
  );
  var _v = ($('#css_test').width() != 1) ? false : true;
  $('#css_test').remove();
  return _v;
};

/**
 *
 * @name onPageLoad
 *
 * @desc The function that displays the image and alters the active classes
 *
 * Note: This function gets called when:
 * 1. after calling $.historyInit();
 * 2. after calling $.historyLoad();
 * 3. after pushing "Go Back" button of a browser
 *
**/

$$.onPageLoad = function(_src) {  

  // get the wrapper
  var _wrapper = $('.galleria_wrapper');

  // get the thumb
  var _thumb = $('.galleria img[rel="'+_src+'"]');

  if (_src) {

    // new hash location
    if ($.galleria.history) {
      window.location = window.location.href.replace(/\#.*/,'') + '#' + _src;
    }

    // alter the active classes
    _thumb.parents('li').siblings('.active').removeClass('active');
    _thumb.parents('li').addClass('active');

    // define a new image
    var _img   = $(new Image()).attr('src',_src).addClass('replaced');

    // empty the wrapper and insert the new image
    _wrapper.empty().append(_img);

    // insert the caption
    _wrapper.siblings('.caption').text(_thumb.attr('title'));

    _wrapper.siblings('.description').text(_thumb.attr('description'));

    // fire the onImage function to customize the loaded image's features
    $.galleria.onImage(_img,_wrapper.siblings('.caption'),_thumb);

    // add clickable image helper
    if($.galleria.clickNext) {
      _img.css('cursor','pointer').click(function() { $.galleria.next(); });
    }
  } else {
    // clean up the container if none are active
    _wrapper.siblings().andSelf().empty();
    // remove active classes
    $('.galleria li.active').removeClass('active');
  }

  // place the source in the galleria.current variable
  $.galleria.current = _src;

};

/**
 *
 * @name jQuery.galleria
 *
 * @desc The global galleria object holds four constant variables and four public methods:
 *       $.galleria.history = a boolean for setting the history object in action with named URLs
 *       $.galleria.current = is the current source that's being viewed.
 *       $.galleria.clickNext = boolean helper for adding a clickable image that leads to the next one in line
 *       $.galleria.next() = displays the next image in line, returns to first image after the last.
 *       $.galleria.prev() = displays the previous image in line, returns to last image after the first.
 *       $.galleria.activate(_src) = displays an image from _src in the galleria container.
 *       $.galleria.onImage(image,caption) = gets fired when the image is displayed.
 *
**/

$.extend({galleria : {
  current : '',
  onImage : function(){},
  activate : function(_src) { 
    if ($.galleria.history) {
      $.historyLoad(_src);
    } else {
      $$.onPageLoad(_src);
    }
  },
  next : function() {
    var _next = $($$.nextSelector($('.galleria img[rel="'+$.galleria.current+'"]').parents('li'))).find('img').attr('rel');
    $.galleria.activate(_next);
  },
  prev : function() {
    var _prev = $($$.previousSelector($('.galleria img[rel="'+$.galleria.current+'"]').parents('li'))).find('img').attr('rel');
    $.galleria.activate(_prev);
  }
}
});

})(jQuery);


/**
 *
 * History extension for jQuery
 * Credits to http://www.mikage.to/
 *
**/


/*
 * jQuery history plugin
 *
 * Copyright (c) 2006 Taku Sano (Mikage Sawatari)
 * Licensed under the MIT License:
 * http://www.opensource.org/licenses/mit-license.php
 *
 * Modified by Lincoln Cooper to add Safari support and only call the callback once during initialization
 * for msie when no initial hash supplied.
 */


jQuery.extend({
  historyCurrentHash: undefined,
  
  historyCallback: undefined,
  
  historyInit: function(callback){
    jQuery.historyCallback = callback;
    var current_hash = location.hash;
    
    jQuery.historyCurrentHash = current_hash;
    if(jQuery.browser.msie) {
      // To stop the callback firing twice during initilization if no hash present
      if (jQuery.historyCurrentHash === '') {
      jQuery.historyCurrentHash = '#';
    }
    
      // add hidden iframe for IE
      $("body").prepend('<iframe id="jQuery_history" style="display: none;"></iframe>');
      var ihistory = $("#jQuery_history")[0];
      var iframe = ihistory.contentWindow.document;
      iframe.open();
      iframe.close();
      iframe.location.hash = current_hash;
    }
    else if ($.browser.safari) {
      // etablish back/forward stacks
      jQuery.historyBackStack = [];
      jQuery.historyBackStack.length = history.length;
      jQuery.historyForwardStack = [];
      
      jQuery.isFirst = true;
    }
    jQuery.historyCallback(current_hash.replace(/^#/, ''));
    setInterval(jQuery.historyCheck, 100);
  },
  
  historyAddHistory: function(hash) {
    // This makes the looping function do something
    jQuery.historyBackStack.push(hash);
    
    jQuery.historyForwardStack.length = 0; // clear forwardStack (true click occured)
    this.isFirst = true;
  },
  
  historyCheck: function(){
    if(jQuery.browser.msie) {
      // On IE, check for location.hash of iframe
      var ihistory = $("#jQuery_history")[0];
      var iframe = ihistory.contentDocument || ihistory.contentWindow.document;
      var current_hash = iframe.location.hash;
      if(current_hash != jQuery.historyCurrentHash) {
        location.hash = current_hash;
        jQuery.historyCurrentHash = current_hash;
        jQuery.historyCallback(current_hash.replace(/^#/, ''));
      }
    } else if ($.browser.safari) {
      if (!jQuery.dontCheck) {
        var historyDelta = history.length - jQuery.historyBackStack.length;
        if (historyDelta) { // back or forward button has been pushed
          jQuery.isFirst = false;
          var i;
          if (historyDelta < 0) { // back button has been pushed
            // move items to forward stack
            for (i = 0; i < Math.abs(historyDelta); i++) {
              jQuery.historyForwardStack.unshift(jQuery.historyBackStack.pop());
            }
          } else { // forward button has been pushed
            // move items to back stack
            for (i = 0; i < historyDelta; i++) {
              jQuery.historyBackStack.push(jQuery.historyForwardStack.shift());
            }
          }
          var cachedHash = jQuery.historyBackStack[jQuery.historyBackStack.length - 1];
          if (cachedHash !== undefined) {
            jQuery.historyCurrentHash = location.hash;
            jQuery.historyCallback(cachedHash);
          }
        } else if (jQuery.historyBackStack[jQuery.historyBackStack.length - 1] === undefined && !jQuery.isFirst) {
          // back button has been pushed to beginning and URL already pointed to hash (e.g. a bookmark)
          // document.URL doesn't change in Safari
          if (document.URL.indexOf('#') >= 0) {
            jQuery.historyCallback(document.URL.split('#')[1]);
          } else {
            current_hash = location.hash;
            jQuery.historyCallback('');
          }
          jQuery.isFirst = true;
        }
      }
    } else {
      // otherwise, check for location.hash
      current_hash = location.hash;
      if(current_hash != jQuery.historyCurrentHash) {
        jQuery.historyCurrentHash = current_hash;
        jQuery.historyCallback(current_hash.replace(/^#/, ''));
      }
    }
  },
  historyLoad: function(hash){
    var newhash;
    
    if (jQuery.browser.safari) {
      newhash = hash;
    }
    else {
      newhash = '#' + hash;
      location.hash = newhash;
    }
    jQuery.historyCurrentHash = newhash;
    
    if(jQuery.browser.msie) {
      var ihistory = $("#jQuery_history")[0];
      var iframe = ihistory.contentWindow.document;
      iframe.open();
      iframe.close();
      iframe.location.hash = newhash;
      jQuery.historyCallback(hash);
    }
    else if (jQuery.browser.safari) {
      jQuery.dontCheck = true;
      // Manually keep track of the history values for Safari
      this.historyAddHistory(hash);
      
      // Wait a while before allowing checking so that Safari has time to update the "history" object
      // correctly (otherwise the check loop would detect a false change in hash).
      var fn = function() {jQuery.dontCheck = false;};
      window.setTimeout(fn, 200);
      jQuery.historyCallback(hash);
      // N.B. "location.hash=" must be the last line of code for Safari as execution stops afterwards.
      //      By explicitly using the "location.hash" command (instead of using a variable set to "location.hash") the
      //      URL in the browser and the "history" object are both updated correctly.
      location.hash = newhash;
    }
    else {
      jQuery.historyCallback(hash);
    }
  }
});