// amazon_to_goodreads.user.js
// version 1.0 
// 2008-09-01
// Copyright (c) 2008, Giacomo Lacava <g.lacava@gmail.com>
// Released under the GPL license v.2
// http://www.gnu.org/copyleft/gpl.html
//
// ==UserScript==
// @name          Amazon to Goodreads
// @description   Add a link on Amazon pages to "see reviews on Goodreads"
// @include       http://www.amazon.*
// ==/UserScript==

var re=/([\/-]|is[bs]n=)(\d{7,9}[\dX])/i;
if(re.test(location.href)==true){
	var isbn = RegExp.$2;
	
	searchUrl = 'http://www.goodreads.com/search/search?q='+isbn+'&group_id=&search_type=books&commit=search'

	reTitle = /\<a\shref="(.*)"\sclass="bookTitle"/gmi ;

	GM_xmlhttpRequest({
		method: 'GET',
		url: searchUrl,
		headers: {
			'User-agent': 'Mozilla/4.0 (compatible) Greasemonkey/0.3',
			'Accept': 'application/atom+xml,application/xml,text/xml',
		},
		onload: function(responseDetails) {
			m = reTitle.exec(responseDetails.responseText);
			if (m.length > 0){
				amzPriceBlock = document.getElementById('btAsinTitle').parentNode.parentNode.nextSibling
				newLink = document.createElement("a");
				newLink.innerHTML = '<a href="'+m[1]+'" target="_blank">See reviews on GoodReads</a><br />';
				amzPriceBlock.parentNode.insertBefore(newLink,amzPriceBlock);
			}
		}
	});
}