var DownloadButton = new function()
{
	function queryParameters() 
	{
		var query = document.location.search;
		var keyValuePairs = query.split(new RegExp('['+decodeURIComponent('%26')+'?]'));
		var params = {};
		for ( var i = 0, n = keyValuePairs.length; i < n; ++i) {
			var m = keyValuePairs[i].match(/^([^=]+)(?:=([\s\S]*))?/);
			if (m) {
				var key = decodeURIComponent(m[1]);
				(params[key] || (params[key] = []))
						.push(decodeURIComponent(m[2]));
			}
		}

		return params;
	}

	this.init = function()
	{
		var queryParams = queryParameters();
		if ('utm_campaign' in queryParams)
		{
			var campaign = queryParams['utm_campaign'][0];
			if (campaign.substr(0,6) == 'promo_')
			{
				jQuery('a[href*="/download"]').each(function(index,obj)
					{
						var promo = campaign.replace('promo_','');
						var url = jQuery(obj).attr('href');
						
						var params = [];
						params.push('src=email');
						params.push('promo='+promo);
						url = 'http://www.wisestamp.com/download?' + params.join(decodeURIComponent('%26'));
						
						jQuery(obj).attr('href',url);
					});
			}
		}
	}
}