/*!
 * jquery even heights plugin
 * author: glen cheney
 * modified: 2014-03-08
 * dependencies: jquery 1.2.6+
 * sets a jquery collection to all be the same height
 * if you need to set multiple collection, please use `$.evenheights( collectionsarray )`
 * because it is much faster
 */

(function( $ ) {
  'use strict';

  function gettallest( $elements ) {
    var tallest = 0;
    $elements.each(function() {
      if ( this.offsetheight > tallest ) {
        tallest = this.offsetheight;
      }
    });
    return tallest;
  }


  $.fn.evenheights = function() {
    return this.css( 'height', '' ).css( 'height', gettallest( this ) );
  };


  /**
   * for groups of elements which should be the same height. using this method
   * will create far less style recalculations and layouts.
   * @param {array.<jquery>} groups array of jquery collections.
   * @return {array.<number>} an array containing the pixel value of the
   *     tallest element for each group.
   */
  $.evenheights = function( groups ) {
    var winners = [];

    // first, reset the height for every element.
    // this is done first, otherwise we dirty the dom on each loop!
    $.each(groups, function( i, $elements ) {
      $elements.css( 'height', '' );
    });

    // now, measure heights in each group and save the tallest value. instead of
    // setting the height value for the entire group, save it. if it were set,
    // the next iteration in the loop would have to recalculate styles in the dom
    $.each(groups, function( i, $elements ) {
      winners.push( gettallest( $elements ) );
    });

    // lastly, set them all.
    $.each(groups, function( i, $elements ) {
      $elements.css( 'height', winners[ i ] );
    });

    return winners;
  };
})(window.$);