(function($) {
 /**
  * Main function; used to initialize the plugin or for calling the available functions provides by the plugin (such as 'open' or 'close').
  * We are going to use the 'arguments' array to obtain the passed parameters
  */
  $.fn.busyBox = function() {

    $.fn.busyBox.self = this;

    if(arguments[0] == 'open') {
      $.fn.busyBox.open();
    } else if(arguments[0] == 'close') {
      $.fn.busyBox.close();
    } else {
      $.fn.busyBox.init(arguments[0]);
    }

    return this;
  };

 /**
  * Initialize the plugin using the passed options
  */
  $.fn.busyBox.init = function(options) {

    $.fn.busyBox.opts = $.extend({}, $.fn.busyBox.defaults, options);

    // Adds the default classes if they are not present in the passed classes
    if($.fn.busyBox.opts.classes.indexOf($.fn.busyBox.defaults.classes) === -1){
      $.fn.busyBox.opts.classes += ' ' + $.fn.busyBox.defaults.classes;
    }

    $.fn.busyBox.container = $(document.body);

    if($.fn.busyBox.opts.autoOpen){
      $.fn.busyBox.open();
    }
  };

 /**
  * Display all the 'busyBoxes' over the matched boxes
  */
  $.fn.busyBox.open = function(){

    var box, inner, e, bOffset, bWidth, bHeight, iTop, iLeft;

    $.fn.busyBox.self.each(function(index) {

      e = $(this);
      bWidth = e.outerWidth();
      bHeight = e.outerHeight();
      bOffset = e.offset();

      box = $('<div>');
      box.attr('id', 'busy_box_' + index);
      box.addClass($.fn.busyBox.opts.classes);

      box.css({
        width: bWidth,
        height: bHeight,
        padding: 0,
        margin: 0,
        position: 'absolute',
        top: bOffset.top,
        left: -9999, // Used to not display the box yet without hidden it (needed to be able to calculate its dimensions)
        zIndex: $.fn.busyBox.opts.zIndex,
        opacity: $.fn.busyBox.opts.opacity,
        color: $.fn.busyBox.opts.color,
        backgroundColor: $.fn.busyBox.opts.backgroundColor
      });

      inner = $($.fn.busyBox.opts.spinner);
      inner.attr('id', 'busy_box_spinner_' + index);
      inner.addClass('busy-box-spinner');

      box.append(inner);

      $.fn.busyBox.container.append(box);

      // Set the position of the inner message inside its parent. Calculates the 'top' and/or 'left' coordinates of the inner-message (inside its parent) if those properties were configured as 'auto'
      iTop = ($.fn.busyBox.opts.top == 'auto' ? ((bHeight / 2) - (inner.outerHeight() / 2)) + 'px' : $.fn.busyBox.opts.top);
      iLeft = ($.fn.busyBox.opts.left == 'auto' ? ((bWidth / 2) - (inner.outerWidth() / 2)) + 'px' : $.fn.busyBox.opts.left);

      inner.css({
        position: 'absolute',
        top: iTop,
        left: iLeft,
        opacity: 1.0
      });

      // Relocate and hidde the 'busyBox' (previously displayed using a negative left-coord to be able to calculate its dimensions)
      box.css({left: bOffset.left, display: 'none'});
    });

    // Display all the 'busyBoxes'
    $.fn.busyBox.container.find('div.' + $.fn.busyBox.defaults.classes).fadeIn('fast');
  };

 /**
  * Closes all the 'busyBoxes' being showed
  */
  $.fn.busyBox.close = function(){
    $.fn.busyBox.container.find('div.' + $.fn.busyBox.defaults.classes).fadeOut('fast', function(){
      $(this).remove();
    });
  };

 /**
  * Default configuration
  */
  $.fn.busyBox.defaults = {
    autoOpen: true,
    spinner: '<em>Cargando…</em>',
    classes: 'busy-box',
    zIndex: 999,
    opacity: 0.5,
    top: 'auto',
    left: 'auto',
    color: '#fff',
    backgroundColor: '#666'
  };

})(jQuery);