Validate Library Card

Performs error detection and correction.

K instalaci tototo skriptu si budete muset nainstalovat rozšíření jako Tampermonkey, Greasemonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Violentmonkey.

K instalaci tohoto skriptu si budete muset nainstalovat rozšíření jako Tampermonkey nebo Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

K instalaci tohoto skriptu si budete muset nainstalovat manažer uživatelských skriptů.

(Už mám manažer uživatelských skriptů, nechte mě ho nainstalovat!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(Už mám manažer uživatelských stylů, nechte mě ho nainstalovat!)

// ==UserScript==
// @name           Validate Library Card
// @namespace      http://mailerdaemon.home.comcast.com/
// @include        https://*.libraryreserve.com/*/SignIn*.htm*
// @include        https://*.libraryreserve.com/*/LogIn*.htm*
// @version        1.0
// @description Performs error detection and correction.
// ==/UserScript==

const extrasize = 3;

function luhn(str){
	if(typeof(str) !== "string")
		str = Array.join(str, "");
	if((str = str.replace(/\D/g, "")).length) {
		var t = [0,2,4,6,8,1,3,5,7,9]
		var [valid, concat] = Array.reduce(str, function([b, a], c){ let j = Number(c); return [a + j, b + t[j]];}, [0, 0]);
		return [str, !(valid % 10), str.concat(9 - (concat + 9) % 10)];
	}
	return [str, undefined, "0"];
}

$Z("//input[(@id='card' or @name='LibraryCardNumber') and @type='text']", function(input){
		let checksum = document.createElement("span");
		insertAfter(checksum, input)
		let update = function (e){
				let value = input.value.replace(/[\s\-_]/g,'');
				let len = value.length;
				let num = Number(value);
				let check;
				if(len && !isNaN(num))
				{
					if(len < 13){
						input.style.backgroundColor = "";
						checksum.innerHTML = check = "";
					}
					else if(len == 13){
						checksum.innerHTML = check = luhn(value)[2].slice(-1);
						input.style.backgroundColor = "#AFA";
					}
					else if(len == 14){
						var [str, success] = luhn(value);
						checksum.innerHTML = ""
						check = str.slice(-1);
						if(success)
							input.style.backgroundColor = "#5F5";
						else
							input.style.backgroundColor = "#FAA";
					}
					else
						input.style.backgroundColor = "#F00";
					//log(value, len, check)
				}
				//else log(value, "wtf?")
				if(input.value.length + extrasize > input.size)
					input.size = input.value.length + extrasize;
			}
		addEvent(input, "keyup", update);
		addEvent(input, "change", update);
		addEvent(checksum, "click", function(){input.value += checksum.innerHTML; update();});
	});

function $Z(_xpath, func, node){
    var doc = (node && (typeof(node.ownerDocument) === "object"))?(node.ownerDocument || node):(node = document);
    var res = doc.evaluate(_xpath, node, null,	XPathResult.ORDERED_NODE_SNAPSHOT_TYPE, null);
    var args = Array.prototype.slice.call(arguments, 3);
    var i = 0;
    for (; i < res.snapshotLength; ++i)
        func.apply(func, [res.snapshotItem(i), i].concat(args));
    return i;
}


function insertAfter(insert, after){return after.parentNode.insertBefore(insert, after.nextSibling);}
function insertBefore(insert, before){return before.parentNode.insertBefore(insert, before);}

function addEvent( obj, type, fn, capture ) {
 	if ( obj.attachEvent ) {
 		obj["e"+type+fn] = fn;
 		obj[type+fn] = function() { obj["e"+type+fn]( window.event ); }
 		obj.attachEvent( "on"+type, obj[type+fn] );
 	} else
 		obj.addEventListener( type, fn, capture?capture:false );
}
function removeEvent( obj, type, fn, capture ) {
 	if ( obj.detachEvent ) {
 		obj.detachEvent( "on"+type, obj[type+fn] );
 		obj[type+fn] = obj["e"+type+fn] = null;
 	} else
 		obj.removeEventListener( type, fn, capture?capture:false );
}
function log(){
	var arg;
	switch(arguments.length)
	{
		case 1:
			arg = arguments[0];
			break;
		case 0:
			arg = null;
			break;
		default:
			arg = arguments;
			break;
	}
	
	var f = arg//JSON.stringify(arg);
	if(typeof(unsafeWindow.console) != "undefined" && typeof(unsafeWindow.console.log) != "undefined")
		unsafeWindow.console.log(f);
	else
		GM_log(f);
	return arg;
}