$(document).ready( mount_magazines_default );

var left_mag;
var slider;
var child;
var childs;

var slider_width;
var child_width;

function mount_magazines_default()
{
  slider = $('.revistas');
  child = $('.revistas ul li');

  childs = $(child).length;
  
  child_width = $(child).outerWidth(true);
  
  slider.width( child_width * childs );
  slider_width = slider.width();
  
  mount_magazines_slider();
}

function mount_magazines_slider()
{
  set_magazines_triggers();
  check_visible_magazines();
}

function set_magazines_triggers()
{
  var next_button;
  var prev_button;
  
  next_button = $('.next_button a');
  prev_button = $('.prev_button a');
  
  next_button.click( next );
  prev_button.click( prev );
}

function next()
{
  $('.revistas').animate({left: -left_mag},{duration:500, easing:"easeOutExpo"});
}

function prev()
{
  $('.revistas').animate({left: 0},{duration:500, easing:"easeOutExpo"});
}

function check_visible_magazines()
{
  var mask;
  var mask_width;
  var appearing;
  var restant;
  
  mask = $('.revistas_container');
  mask_width = mask.width();
  
  appearing = Math.round( mask_width / child_width );
  restant = childs - appearing;
  
  left_mag = restant * child_width;
}