// ==UserScript==
// @name           Wait for it
// @namespace      http://userscripts.org/scripts/show/128187
// @description    Wait for something. Silently reloads the page every X seconds until some condition is met
// @version        1.02
// @include        *
// ==/UserScript==
GM_registerMenuCommand('Wait for something...', function(){
var search = prompt('Wait for what?\n'+
'Can be some literal text in the page, a regular expression, CSS selector or XPath query\n'+
'Leave blank to wait for any change',
localStorage['wfi_wfw'] || '');
if(search === null) return;
var html = null;
try{ var re = new RegExp(search, 'i'); }
catch(e){ re = null; }
function check(doc){
if(!search){
if(doc == document) return false;
var d = doc.documentElement.innerHTML;
if(!html) html = d;
return html != d;
}
//CSS
try{ if(doc.querySelector(search)) return true; }
catch(e){}
//XPath
try{
var res = doc.evaluate(search, doc, null, XPathR###lt.ANY_UNORDERED_NODE_TYPE, null);
if(res.singleNodeValue) return true;
}
catch(e){}
//RegExp
if(re && re.test(doc.documentElement.textContent)) return true;
//text
return doc.documentElement.textContent.indexOf(search) > -1;
}
if(check(document)){
alert('"'+search+'" is already there, nothing to wait for...');
return;
}
var secs = prompt('Check every how many seconds?', localStorage['wfi_secs'] || 30)*1;
if(!secs) return;
localStorage['wfi_wfw'] = search;
localStorage['wfi_secs'] = secs;
var div = document.createElement('div');
div.innerHTML = 'Waiting for '+(search ? '"'+search+'"' : 'anything')+' every '+secs+' seconds... Last checked at <span id="wfi_last"/>';
div.style.position = 'fixed';
div.style.top = '0';
div.style.left = '0';
div.style.backgroundColor = '#ffc';
document.body.appendChild(div);
var last = document.getElementById('wfi_last');
var xhr = new XMLHttpRequest();
function load(){
document.body.removeChild(div);
if(check(document)){
alert((search ? '"'+search+'"' : 'somehing')+' found in '+document.title);
}
else{
document.body.appendChild(div);
xhr.open('GET', document.location.href, true);
xhr.send();
last.innerHTML = new Date();
}
}
var doc = document.implementation.createHTMLDocument('');
xhr.onreadystatechange = function(){
if (xhr.readyState == 4 && xhr.status == 200){
doc.documentElement.innerHTML = xhr.responseText;
if(check(doc)){
alert((search ? '"'+search+'"' : 'somehing')+' found in '+document.title);
document.location.reload();
}
else setTimeout(load, secs*1000);
}
};
load();
});