twitterdrit.user.js

/**
 * @fileOverview
 * This file is a GreaseMonkey user script containing various Twitter hacks.
 *
 * Changelog
 * ---------
 * Version 1.0 (2009-11-07):
 * - adds "Following you" to users in following/followers pages
 *
 * @author       <a href="http://twitter.com/robinsk">Robin Skoglund</a>
 * @version      1.0
 */
 
// ==UserScript==
// @name           Twitterdrit
// @namespace      http://dev.robinsk.net/twitter
// @description    Various Twitter hacks.
// @include        http://twitter.com/*
// ==/UserScript==

/**
 * Runs an XPath query
 *
 * @param  {String} query        XPath query to evaluate
 * @param  {Number} resultType   [optional] One of the XPathResult constants.
 * @param  {Node}   contextNode  [optional] Context node for evaluation.
 * @return The XPathResult of the evaluated query, or simple value if the 
           resultType is one of NUMBER_TYPE, STRING_TYPE, or BOOLEAN_TYPE.
 */
function xpath(query, resultType, contextNode) {
    if (!resultType) resultType = XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE;
    if (!contextNode) contextNode = document;
    var result = document.evaluate(query, contextNode, null, resultType, null);
    switch (resultType) {
        case XPathResult.NUMBER_TYPE:
            return result.numberValue;
        case XPathResult.STRING_TYPE:
            return result.stringValue;
        case XPathResult.BOOLEAN_TYPE:
            return result.booleanValue;
        default:
            return result;
    }
}

/**
 * Adds "Following you" to users following you.
 */
function addIsFollowingYouRelationship() {
    var followGrid = document.getElementById('follow_grid');
    if (!followGrid) return;
    var q = 'table/tbody/tr[contains(@class, "direct-messageable")]'
          + '/td[@class = "user-detail"]/address'
          + '/span[@class = "is-relationship"]';
    var allRelationships = xpath(q, null, followGrid);
    
    for (var i = 0; i < allRelationships.snapshotLength; i++) {
        var relationship = allRelationships.snapshotItem(i);
        q = 'span[contains(@class, "screenname")]/a = "' + sessionUser + '"';
        if (xpath(q, XPathResult.BOOLEAN_TYPE, relationship.parentNode)) {
            // That's you!
            continue;
        }
        
        var followingYou = document.createElement('span');
        followingYou.className = 'is-following';
        followingYou.style.display = 'inline-block';
        if (relationship.children.length > 0) {
            // put "Following you" below "Following"
            followingYou.style.top = '18px';
        }
        
        var lbl = document.createElement('strong');
        lbl.innerHTML = 'Following you';
        
        followingYou.appendChild(document.createElement('i'));
        followingYou.appendChild(lbl);
        relationship.appendChild(followingYou);
    }
}

/**
 * Session user's screen name.
 * @type String
 */
var sessionUser = xpath('//meta[@name = "session-user-screen_name"]/@content', XPathResult.STRING_TYPE);

/**
 * Page user's screen name.
 * @type String
 */
var pageUser = xpath('//meta[@name = "page-user-screen_name"]/@content', XPathResult.STRING_TYPE);

// Add "Following you" to follow grids (except for your own followers list, 
// that would be silly).
if (sessionUser != pageUser ||
    !window.location.pathname.match(/\/followers$/)) {
    addIsFollowingYouRelationship();
}