/**
* Purpose:              Font sizer class, handles increasing and decreasing font size of a page.
*                       It increases the font in 10% increments. By getting the level / 10 + 1.
*                       i.e. level 2 is .2 + 1 so 1.2 or 120%.
*
* Requires:             JQuery and the JQuery cookies plugin.
*
* Use:                  Setup the fontsizer $.FontSizer.Init(options); the two options are
*                       min and max, for the min level and max level.
*                       Defaults are min: -3 and max: 5.
*
* Author:               Stefan Sedich (stefan.sedich@gmail.com
*/
$.FontSizer = {
  
  level: 0,
  
  options: { min: -3, max: 5 },
  
  Init: function(options) {
    if(options)
      $.FontSizer.options = $.extend($.FontSizer.options, options);
    
    //Get the current level from cookies.
    var level = ($.cookie('font_level') != null) ? $.cookie('font_level') : 0;
    
    //Set the font size to the current leve.
    $.FontSizer.SetSize(level);
    
  },
  
  IncreaseSize: function() {
  
    if(($.FontSizer.level + 1) <= $.FontSizer.options.max) {
      //If we have not exceded the max level,
      //Get the next level and the set the size to this level.
      var next = (parseInt($.FontSizer.level) + 1);
      $.FontSizer.SetSize(next);
    }
  
  },
  
  DecreaseSize: function() {
  
    if(($.FontSizer.level - 1) >= $.FontSizer.options.min) {
      //If we have not exceded the min level,
      //Get the next level and the set the size to this level.
      var next = (parseInt($.FontSizer.level) - 1);
      $.FontSizer.SetSize(next);
    }
  
  },
  
  SetSize: function(level) {
  
    //Set the current level in the member variable and the cookie.
    $.FontSizer.level = level;      
    $.cookie('font_level', level, { path:'/' });
    
    //Work out the new em value and set it.
    var level = (level / 10) + 1;
    $('#page-margins').css("fontSize", level+"em");
    
    // hide or show the button
    $.FontSizer.ChangeButton();
    
  },
  
  Reset: function() {
    //Reset the level back to 0
    $.FontSizer.SetSize(0);
    
    // hide or show the button
    $.FontSizer.ChangeButton();
    
  },
  
  ChangeButton: function() {
    if ($.FontSizer.level == $.FontSizer.options.min) { $('.fs-minus').css('display','none'); $('.fs-minus1').css('display','inline'); } else { $('.fs-minus').css('display','inline'); $('.fs-minus1').css('display','none'); }
    if ($.FontSizer.level == $.FontSizer.options.max) { $('.fs-plus').css('display','none'); $('.fs-plus1').css('display','inline'); } else { $('.fs-plus').css('display','inline'); $('.fs-plus1').css('display','none'); }
  }

};