Advertisement = Class.create();
Advertisement.prototype = {
  initialize: function(size) {
    this.size = size;
    if (advertisements[this.size]) {
      var count = advertisements[this.size].length;
      var random = parseInt(Math.random()*count);
      this.ad = advertisements[this.size][random];
    }
    else {
      console.error("Unable to generate advertisement.");
    }
  },
  
  getHTML: function() {
    if (this.ad.mouseover) {
      return this.templates[this.size + "_mouseover"].process(this.ad);
    }
    else {
      return this.templates[this.size].process(this.ad);
    }
  },
  
  renderToPage: function() {
    document.write(this.getHTML());
  },
  
  templates: {
    '300x250':  '<div class="square_ad">' +
            			'<div class="square_advertisement_callout">' +
            				'Advertisement <img src="/images/AdvertisementDownArrow.png" alt="" />' +
            			'</div>' +
            			'<div class="ad300x250">' +
            				'<a href="${link}" target="_BLANK"><img src="/images/ads/${image}" alt=""/></a>' +
            			'</div>' +
            		'</div>',
    '300x250-b':  '<div class="square_ad">' +
            			'<div class="square_advertisement_callout">' +
            				'Advertisement <img src="/images/AdvertisementDownArrow.png" alt="" />' +
            			'</div>' +
            			'<div class="ad300x250">' +
            				'<a href="${link}" target="_BLANK"><img src="/images/ads/${image}" alt=""/></a>' +
            			'</div>' +
            		'</div>',
    'tshirt':  '<div class="square_ad">' +
            			'<div class="square_advertisement_callout">' +
            				'Advertisement <img src="/images/AdvertisementDownArrow.png" alt="" />' +
            			'</div>' +
            			'<div class="ad300x250">' +
            				'<a href="${link}" target="_BLANK"><img src="/images/ads/${image}" alt=""/></a>' +
            			'</div>' +
            		'</div>',
    'tshirt_mouseover':  '<div class="square_ad">' +
            			'<div class="square_advertisement_callout">' +
            				'Advertisement <img src="/images/AdvertisementDownArrow.png" alt="" />' +
            			'</div>' +
            			'<div class="ad300x250">' +
            				'<a href="${link}" target="_BLANK"><img src="/images/ads/${image}" ' +
            				'onmouseover="if (this.src != \'/images/ads/${mouseover}\') this.src=\'/images/ads/${mouseover}\';" ' +
            				'onmouseout="if (this.src != \'/images/ads/${image}\')this.src=\'/images/ads/${image}\';" ' +
            				' alt=""/></a>' +
            			'</div>' +
            		'</div>',
    '728x90':   '<div class="banner_ad">' +
      						'<div class="ad728x90">' +
      							'<a href="${link}" target="_BLANK"><img src="/images/ads/${image}" alt="" class="ad banner bottom_of_page" /></a>' +
      							'<div class="banner_advertisement_callout">' +
      								'<img src="/images/AdvertisementUpArrow.png" alt="" /> Advertisement' +
      							'</div></div></div>',
    '160x600':  '<div class="skyscraper_ad">' +
            			'<div class="skyscraper_advertisement_callout">' +
            				'Advertisement <img src="/images/AdvertisementDownArrow.png" alt="" />' +
            			'</div>' +
            			'<div class="ad160x600">' +
            				'<a href="${link}" target="_BLANK"><img src="/images/ads/${image}" alt="" class="ad wide_skyscraper" /></a>' +
            			'</div>' +
            		'</div>'
  }
};