// ==UserScript==
// @name        Github Commit Whitespace
// @namespace   https://github.com/jerone/UserScripts
// @description Adds button to hide whitespaces from commit
// @author      jerone
// @copyright   2014+, jerone (http://jeroenvanwarmerdam.nl)
// @license     GNU GPLv3
// @homepage    https://github.com/jerone/UserScripts/tree/master/Github_Commit_Whitespace
// @homepageURL https://github.com/jerone/UserScripts/tree/master/Github_Commit_Whitespace
// @supportURL  https://github.com/jerone/UserScripts/issues
// @contributionURL https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=VCYMHWQ7ZMBKW
// @icon        https://github.com/fluidicon.png
// @include     https://github.com/*
// @version     1.4.4
// @grant       none
// @downloadURL none
// ==/UserScript==
/* global unsafeWindow */

(function() {

    function addButton() {
        var e;
        if ((/\/commit\//.test(location.href) || /\/compare\//.test(location.href)) && (e = document.getElementById("toc"))) {

            var r = e.querySelector(".GithubCommitWhitespaceButton");
            if (r) {
                r.parentElement.removeChild(r);
            }

            var on = /w=/.test(location.search); // any occurense results in enabling;

            var b = e.querySelector(".toc-diff-stats");

            var a = document.createElement("a");
            a.classList.add("btn", "btn-sm", "tooltipped", "tooltipped-n");
            if (on) {
                a.classList.add("selected");
            }
            a.setAttribute("href", url(on));
            a.setAttribute("rel", "nofollow");
            a.setAttribute("aria-label", on ? "Show commit whitespace" : "Hide commit whitespace");
            a.appendChild(document.createTextNode(" \u2423"));

            var g = document.createElement("div");
            g.classList.add("GithubCommitWhitespaceButton", "right");
            g.style.margin = "0 10px 0 0"; // give us some room;
            g.appendChild(a);

            b.parentNode.insertBefore(g, b);
        } else if (/\/pull\/\d*\/files/.test(location.href) && (e = document.querySelector("#files_bucket .pr-toolbar .diffbar > .float-right"))) {

            var r = e.querySelector(".GithubCommitWhitespaceButton");
            if (r) {
                r.parentElement.removeChild(r);
            }

            var on = /w=/.test(location.search); // any occurense results in enabling;

            var a = document.createElement("a");
            a.classList.add("btn-link", "muted-link");
            a.setAttribute("href", url(on));
            a.setAttribute("rel", "nofollow");
            a.setAttribute("aria-label", on ? "Show commit whitespace" : "Hide commit whitespace");
            a.appendChild(document.createTextNode(on ? "Show whitespace" : "Hide whitespace"));

            var g = document.createElement("div");
            g.classList.add("GithubCommitWhitespaceButton", "diffbar-item");
            g.appendChild(a);

            e.insertBefore(g, e.firstChild);
        }
    }

    function url(on) {
        var searches = location.search.replace(/^\?/, "").split("&").filter(function(item) {
            return item && !/w=.*/.test(item);
        });
        if (!on) {
            searches.push("w=1");
        }
        return location.href.replace(location.search, "") + (searches.length > 0 ? "?" + searches.join("&") : "");
    }

    // init;
    addButton();

    // on pjax;
    document.addEventListener('pjax:end', addButton);

})();