embed_typograffit.user.js

// ==UserScript==
// @name           embed typograffit
// @namespace      http://www.relucks.org/
// @include        http://twitter.com/
// ==/UserScript==

(function() {
    var loaded = {}
    url2img(document)
    document.addEventListener("DOMNodeInserted", function(e){
        if (e.target.tagName) {
            setTimeout(function() { url2img(e.target) }, 100)
        }
    }, false)

    function url2img(doc) {
        var re_t = new RegExp('^http://typograffit\.com/posts/compose/')
        $X('.//a[@href]', doc).forEach(function(a) {
            if (re_t.test(a.href) && !loaded[a.href]) {
                loaded[a.href] = true
                replace_typograffit(a)
            }
        })
    }

    function replace_typograffit(a) {
        var img = document.createElement('img')
        img.src = a.href.replace('compose', 'getImage')
        img.style.maxWidth = '400px'
        a.appendChild(img)
    }

    // http://gist.github.com/raw/3242/1a7950e033a207efcfc233ae8d9939b676bdbf46
    // simple version of $X
    // $X(exp);
    // $X(exp, context);
    function $X (exp, context) {
        context || (context = document);
        var expr = (context.ownerDocument || context).createExpression(exp, function (prefix) {
            return document.createNSResolver(context)(prefix) ||
                (document.contentType == "application/xhtml+xml") ? "http://www.w3.org/1999/xhtml" : "";
        });

        var result = expr.evaluate(context, XPathResult.ANY_TYPE, null);
        switch (result.resultType) {
            case XPathResult.STRING_TYPE : return result.stringValue;
            case XPathResult.NUMBER_TYPE : return result.numberValue;
            case XPathResult.BOOLEAN_TYPE: return result.booleanValue;
            case XPathResult.UNORDERED_NODE_ITERATOR_TYPE:
                // not ensure the order.
            var ret = [], i = null;
            while (i = result.iterateNext()) ret.push(i);
                return ret;
        }
        return null;
    }
})()