Formats image links real quick

fv_new_items.user.js

// ==UserScript==
// @name         FV New Items Formatter
// @author       msjanny (7302)
// @description  Given an item image index sorted by recent, returns linked images
// @version      0.1
// @include        /http://www\.furvilla\.com/img/items/\d+/\?MD/
// ==/UserScript==

(function() {

    // gets array of links
    var html = document.getElementsByTagName("a");
    var links = Array.prototype.slice.call(html);
    links.splice(0, 5);

    // prompts for range
    var lastItem = links[0].href.split(/img\/items\/\d+\//)[1].split('-')[0];
    var minimum = links[links.length - 1].href.split(/img\/items\/\d+\//)[1].split('-')[0];
    var firstItem = prompt("First item ID");
    var valid = firstItem <= lastItem && minimum <= firstItem;
    while (!valid) {
        firstItem = prompt("First item ID must be less than or equal to " + lastItem + " and greater than or equal to " + minimum + ".");
        valid = firstItem <= lastItem && minimum <= firstItem;
    }

    // finds image URLs and IDs
    links = links.slice(0, lastItem - firstItem + 1);
    var images = [];
    var itemIDs = [];
    for ( x = 0; x < links.length ; x++ ) {
        images.unshift(links[x].href);
        itemIDs.unshift(links[x].href.split(/img\/items\/\d+\//)[1].split('-')[0]);
    }

    // bbcode concantenation
    var bbcode = "";
    for ( x = 0; x < images.length ; x++) {
        bbcode = bbcode + "[url=http://www.furvilla.com/museum/items?id=" + itemIDs[x] + "][img]" + images[x] + "[/img][/url]";
    }

    document.getElementsByTagName("h1")[0].innerHTML = document.getElementsByTagName("h1")[0].innerHTML + '<textarea style="float: right;">' + bbcode + "</textarea>";

})();