// ==UserScript==
// @name         Go.dev Golang Website Code Highlight
// @version      1.1.7
// @description  Golang code highlighter
// @author       Anton Vi
// @match        https://*.go.dev/*

// @resource     IMPORTED_CSS  https://cdnjs.cloudflare.com/ajax/libs/prism/1.29.0/themes/prism-tomorrow.min.css

// @grant        GM_getResourceText
// @grant        GM_addStyle
// @license      GNU GPLv3

// @exclude      https://go.dev/tour/*
// @exclude      https://go.dev/solutions/*
// @exclude      https://go.dev/security/*
// @namespace GolangDevNamespace
// @downloadURL https://update.greasyfork.icu/scripts/482660/Godev%20Golang%20Website%20Code%20Highlight.user.js
// @updateURL https://update.greasyfork.icu/scripts/482660/Godev%20Golang%20Website%20Code%20Highlight.meta.js
// ==/UserScript==

(function() {

    'use strict';

    document.addEventListener('readystatechange', (e) => {
        if (e.target.readyState === 'complete') {
            resetBlogCss();
            start();
        }
    })


})();

function resetBlogCss() {
    // reset styles for go dev blog
    let css = `#blog pre, #content .code, #content .playground {
        background: black; 
        font-family: Consolas,Monaco,'Andale Mono','Ubuntu Mono',monospace;
        font-size: 1rem;
    }`;
    GM_addStyle(css);

}

function start() {
    // create Prisma object
    window.Prism = window.Prism || {};
    // no highlight on auto
    Prism.manual = true;

    // add highlight styles css
    const my_css = GM_getResourceText("IMPORTED_CSS");
    GM_addStyle(my_css);


    // loop pre-s and add code child elements for highlight
    let pre_s = document.getElementsByTagName('pre');
    for (let el of pre_s) {
        // skip pre element for ==Output== code run in documentation
        if (el.getElementsByClassName('Documentation-exampleOutputLabel').length > 0) {
            continue;
        }

        el.className = 'language-go';


        if (!el.getElementsByTagName('code').length > 0) {
            let text = el.innerHTML;
            el.innerHTML = '';

            let code = document.createElement('code');
            code.innerHTML = text;
            code.className = 'language-go';
            el.appendChild(code);
        }

    }


    // get examples in go library doc
    let divS = document.getElementsByClassName('Documentation-exampleDetailsBody');
    for (divEl of divS) {
        let outputPre = divEl.getElementsByTagName('pre')[0];
        outputPre.className = 'language-go';


        let textareaBlock = divEl.querySelector('textarea.Documentation-exampleCode.code');
        textareaBlock.style.display = 'none';
        // textareaBlock.remove();
        divEl.insertAdjacentHTML('afterbegin', '<pre class="language-go"><code>' + textareaBlock.value + '</code></pre>');


    }


    // start prism
    initPrismCore();

    // add languages syntax
    addClikeSyntax();
    addGoSyntax();


    // start highlight syntax
    Prism.highlightAll();

}

function initPrismCore() {
    var _self = "undefined" != typeof window ? window : "undefined" != typeof WorkerGlobalScope && self instanceof WorkerGlobalScope ? self : {},
        Prism = function(e) {
            var n = /(?:^|\s)lang(?:uage)?-([\w-]+)(?=\s|$)/i,
                t = 0,
                r = {},
                a = {
                    manual: e.Prism && e.Prism.manual,
                    disableWorkerMessageHandler: e.Prism && e.Prism.disableWorkerMessageHandler,
                    util: {
                        encode: function e(n) { return n instanceof i ? new i(n.type, e(n.content), n.alias) : Array.isArray(n) ? n.map(e) : n.replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/\u00a0/g, " ") },
                        type: function(e) { return Object.prototype.toString.call(e).slice(8, -1) },
                        objId: function(e) { return e.__id || Object.defineProperty(e, "__id", { value: ++t }), e.__id },
                        clone: function e(n, t) {
                            var r, i;
                            switch (t = t || {}, a.util.type(n)) {
                                case "Object":
                                    if (i = a.util.objId(n), t[i]) return t[i];
                                    for (var l in r = {}, t[i] = r, n) n.hasOwnProperty(l) && (r[l] = e(n[l], t));
                                    return r;
                                case "Array":
                                    return i = a.util.objId(n), t[i] ? t[i] : (r = [], t[i] = r, n.forEach((function(n, a) { r[a] = e(n, t) })), r);
                                default:
                                    return n
                            }
                        },
                        getLanguage: function(e) {
                            for (; e;) {
                                var t = n.exec(e.className);
                                if (t) return t[1].toLowerCase();
                                e = e.parentElement
                            }
                            return "none"
                        },
                        setLanguage: function(e, t) { e.className = e.className.replace(RegExp(n, "gi"), ""), e.classList.add("language-" + t) },
                        currentScript: function() {
                            if ("undefined" == typeof document) return null;
                            if ("currentScript" in document) return document.currentScript;
                            try { throw new Error } catch (r) {
                                var e = (/at [^(\r\n]*\((.*):[^:]+:[^:]+\)$/i.exec(r.stack) || [])[1];
                                if (e) {
                                    var n = document.getElementsByTagName("script");
                                    for (var t in n)
                                        if (n[t].src == e) return n[t]
                                }
                                return null
                            }
                        },
                        isActive: function(e, n, t) {
                            for (var r = "no-" + n; e;) {
                                var a = e.classList;
                                if (a.contains(n)) return !0;
                                if (a.contains(r)) return !1;
                                e = e.parentElement
                            }
                            return !!t
                        }
                    },
                    languages: {
                        plain: r,
                        plaintext: r,
                        text: r,
                        txt: r,
                        extend: function(e, n) { var t = a.util.clone(a.languages[e]); for (var r in n) t[r] = n[r]; return t },
                        insertBefore: function(e, n, t, r) {
                            var i = (r = r || a.languages)[e],
                                l = {};
                            for (var o in i)
                                if (i.hasOwnProperty(o)) {
                                    if (o == n)
                                        for (var s in t) t.hasOwnProperty(s) && (l[s] = t[s]);
                                    t.hasOwnProperty(o) || (l[o] = i[o])
                                } var u = r[e];
                            return r[e] = l, a.languages.DFS(a.languages, (function(n, t) { t === u && n != e && (this[n] = l) })), l
                        },
                        DFS: function e(n, t, r, i) {
                            i = i || {};
                            var l = a.util.objId;
                            for (var o in n)
                                if (n.hasOwnProperty(o)) {
                                    t.call(n, o, n[o], r || o);
                                    var s = n[o],
                                        u = a.util.type(s);
                                    "Object" !== u || i[l(s)] ? "Array" !== u || i[l(s)] || (i[l(s)] = !0, e(s, t, o, i)) : (i[l(s)] = !0, e(s, t, null, i))
                                }
                        }
                    },
                    plugins: {},
                    highlightAll: function(e, n) { a.highlightAllUnder(document, e, n) },
                    highlightAllUnder: function(e, n, t) {
                        var r = { callback: t, container: e, selector: 'code[class*="language-"], [class*="language-"] code, code[class*="lang-"], [class*="lang-"] code' };
                        a.hooks.run("before-highlightall", r), r.elements = Array.prototype.slice.apply(r.container.querySelectorAll(r.selector)), a.hooks.run("before-all-elements-highlight", r);
                        for (var i, l = 0; i = r.elements[l++];) a.highlightElement(i, !0 === n, r.callback)
                    },
                    highlightElement: function(n, t, r) {
                        var i = a.util.getLanguage(n),
                            l = a.languages[i];
                        a.util.setLanguage(n, i);
                        var o = n.parentElement;
                        o && "pre" === o.nodeName.toLowerCase() && a.util.setLanguage(o, i);
                        var s = { element: n, language: i, grammar: l, code: n.textContent };

                        function u(e) { s.highlightedCode = e, a.hooks.run("before-insert", s), s.element.innerHTML = s.highlightedCode, a.hooks.run("after-highlight", s), a.hooks.run("complete", s), r && r.call(s.element) }
                        if (a.hooks.run("before-sanity-check", s), (o = s.element.parentElement) && "pre" === o.nodeName.toLowerCase() && !o.hasAttribute("tabindex") && o.setAttribute("tabindex", "0"), !s.code) return a.hooks.run("complete", s), void(r && r.call(s.element));
                        if (a.hooks.run("before-highlight", s), s.grammar)
                            if (t && e.Worker) {
                                var c = new Worker(a.filename);
                                c.onmessage = function(e) { u(e.data) }, c.postMessage(JSON.stringify({ language: s.language, code: s.code, immediateClose: !0 }))
                            } else u(a.highlight(s.code, s.grammar, s.language));
                        else u(a.util.encode(s.code))
                    },
                    highlight: function(e, n, t) { var r = { code: e, grammar: n, language: t }; if (a.hooks.run("before-tokenize", r), !r.grammar) throw new Error('The language "' + r.language + '" has no grammar.'); return r.tokens = a.tokenize(r.code, r.grammar), a.hooks.run("after-tokenize", r), i.stringify(a.util.encode(r.tokens), r.language) },
                    tokenize: function(e, n) {
                        var t = n.rest;
                        if (t) {
                            for (var r in t) n[r] = t[r];
                            delete n.rest
                        }
                        var a = new s;
                        return u(a, a.head, e), o(e, a, n, a.head, 0),
                            function(e) { for (var n = [], t = e.head.next; t !== e.tail;) n.push(t.value), t = t.next; return n }(a)
                    },
                    hooks: {
                        all: {},
                        add: function(e, n) {
                            var t = a.hooks.all;
                            t[e] = t[e] || [], t[e].push(n)
                        },
                        run: function(e, n) {
                            var t = a.hooks.all[e];
                            if (t && t.length)
                                for (var r, i = 0; r = t[i++];) r(n)
                        }
                    },
                    Token: i
                };

            function i(e, n, t, r) { this.type = e, this.content = n, this.alias = t, this.length = 0 | (r || "").length }

            function l(e, n, t, r) {
                e.lastIndex = n;
                var a = e.exec(t);
                if (a && r && a[1]) {
                    var i = a[1].length;
                    a.index += i, a[0] = a[0].slice(i)
                }
                return a
            }

            function o(e, n, t, r, s, g) {
                for (var f in t)
                    if (t.hasOwnProperty(f) && t[f]) {
                        var h = t[f];
                        h = Array.isArray(h) ? h : [h];
                        for (var d = 0; d < h.length; ++d) {
                            if (g && g.cause == f + "," + d) return;
                            var v = h[d],
                                p = v.inside,
                                m = !!v.lookbehind,
                                y = !!v.greedy,
                                k = v.alias;
                            if (y && !v.pattern.global) {
                                var x = v.pattern.toString().match(/[imsuy]*$/)[0];
                                v.pattern = RegExp(v.pattern.source, x + "g")
                            }
                            for (var b = v.pattern || v, w = r.next, A = s; w !== n.tail && !(g && A >= g.reach); A += w.value.length, w = w.next) {
                                var E = w.value;
                                if (n.length > e.length) return;
                                if (!(E instanceof i)) {
                                    var P, L = 1;
                                    if (y) {
                                        if (!(P = l(b, A, e, m)) || P.index >= e.length) break;
                                        var S = P.index,
                                            O = P.index + P[0].length,
                                            j = A;
                                        for (j += w.value.length; S >= j;) j += (w = w.next).value.length;
                                        if (A = j -= w.value.length, w.value instanceof i) continue;
                                        for (var C = w; C !== n.tail && (j < O || "string" == typeof C.value); C = C.next) L++, j += C.value.length;
                                        L--, E = e.slice(A, j), P.index -= A
                                    } else if (!(P = l(b, 0, E, m))) continue;
                                    S = P.index;
                                    var N = P[0],
                                        _ = E.slice(0, S),
                                        M = E.slice(S + N.length),
                                        W = A + E.length;
                                    g && W > g.reach && (g.reach = W);
                                    var z = w.prev;
                                    if (_ && (z = u(n, z, _), A += _.length), c(n, z, L), w = u(n, z, new i(f, p ? a.tokenize(N, p) : N, k, N)), M && u(n, w, M), L > 1) {
                                        var I = { cause: f + "," + d, reach: W };
                                        o(e, n, t, w.prev, A, I), g && I.reach > g.reach && (g.reach = I.reach)
                                    }
                                }
                            }
                        }
                    }
            }

            function s() {
                var e = { value: null, prev: null, next: null },
                    n = { value: null, prev: e, next: null };
                e.next = n, this.head = e, this.tail = n, this.length = 0
            }

            function u(e, n, t) {
                var r = n.next,
                    a = { value: t, prev: n, next: r };
                return n.next = a, r.prev = a, e.length++, a
            }

            function c(e, n, t) {
                for (var r = n.next, a = 0; a < t && r !== e.tail; a++) r = r.next;
                n.next = r, r.prev = n, e.length -= a
            }
            if (e.Prism = a, i.stringify = function e(n, t) {
                    if ("string" == typeof n) return n;
                    if (Array.isArray(n)) { var r = ""; return n.forEach((function(n) { r += e(n, t) })), r }
                    var i = { type: n.type, content: e(n.content, t), tag: "span", classes: ["token", n.type], attributes: {}, language: t },
                        l = n.alias;
                    l && (Array.isArray(l) ? Array.prototype.push.apply(i.classes, l) : i.classes.push(l)), a.hooks.run("wrap", i);
                    var o = "";
                    for (var s in i.attributes) o += " " + s + '="' + (i.attributes[s] || "").replace(/"/g, "&quot;") + '"';
                    return "<" + i.tag + ' class="' + i.classes.join(" ") + '"' + o + ">" + i.content + "</" + i.tag + ">"
                }, !e.document) return e.addEventListener ? (a.disableWorkerMessageHandler || e.addEventListener("message", (function(n) {
                var t = JSON.parse(n.data),
                    r = t.language,
                    i = t.code,
                    l = t.immediateClose;
                e.postMessage(a.highlight(i, a.languages[r], r)), l && e.close()
            }), !1), a) : a;
            var g = a.util.currentScript();

            function f() { a.manual || a.highlightAll() }
            if (g && (a.filename = g.src, g.hasAttribute("data-manual") && (a.manual = !0)), !a.manual) { var h = document.readyState; "loading" === h || "interactive" === h && g && g.defer ? document.addEventListener("DOMContentLoaded", f) : window.requestAnimationFrame ? window.requestAnimationFrame(f) : window.setTimeout(f, 16) }
            return a
        }(_self);
    "undefined" != typeof module && module.exports && (module.exports = Prism), "undefined" != typeof global && (global.Prism = Prism);
}

function addClikeSyntax() {
    Prism.languages.clike = {
        comment: [{ pattern: /(^|[^\\])\/\*[\s\S]*?(?:\*\/|$)/, lookbehind: !0, greedy: !0 },
            { pattern: /(^|[^\\:])\/\/.*/, lookbehind: !0, greedy: !0 }
        ],
        string: { pattern: /(["'])(?:\\(?:\r\n|[\s\S])|(?!\1)[^\\\r\n])*\1/, greedy: !0 },
        "class-name": { pattern: /(\b(?:class|extends|implements|instanceof|interface|new|trait)\s+|\bcatch\s+\()[\w.\\]+/i, lookbehind: !0, inside: { punctuation: /[.\\]/ } },
        keyword: /\b(?:break|catch|continue|do|else|finally|for|function|if|in|instanceof|new|null|return|throw|try|while)\b/,
        boolean: /\b(?:false|true)\b/,
        function: /\b\w+(?=\()/,
        number: /\b0x[\da-f]+\b|(?:\b\d+(?:\.\d*)?|\B\.\d+)(?:e[+-]?\d+)?/i,
        operator: /[<>]=?|[!=]=?=?|--?|\+\+?|&&?|\|\|?|[?*/~^%]/,
        punctuation: /[{}[\];(),.:]/
    };
}

function addGoSyntax() {
    Prism.languages.go = Prism.languages
        .extend("clike", {
            string: { pattern: /(^|[^\\])"(?:\\.|[^"\\\r\n])*"|`[^`]*`/, lookbehind: !0, greedy: !0 },
            keyword: /\b(?:break|case|chan|const|continue|default|defer|else|fallthrough|for|func|go(?:to)?|if|import|interface|map|package|range|return|select|struct|switch|type|var)\b/,
            boolean: /\b(?:_|false|iota|nil|true)\b/,
            number: [/\b0(?:b[01_]+|o[0-7_]+)i?\b/i, /\b0x(?:[a-f\d_]+(?:\.[a-f\d_]*)?|\.[a-f\d_]+)(?:p[+-]?\d+(?:_\d+)*)?i?(?!\w)/i, /(?:\b\d[\d_]*(?:\.[\d_]*)?|\B\.\d[\d_]*)(?:e[+-]?[\d_]+)?i?(?!\w)/i],
            operator: /[*\/%^!=]=?|\+[=+]?|-[=-]?|\|[=|]?|&(?:=|&|\^=?)?|>(?:>=?|=)?|<(?:<=?|=|-)?|:=|\.\.\./,
            builtin: /\b(?:append|bool|byte|cap|close|complex|complex(?:64|128)|copy|delete|error|float(?:32|64)|u?int(?:8|16|32|64)?|imag|len|make|new|panic|print(?:ln)?|real|recover|rune|string|uintptr)\b/
        }),
        Prism.languages.insertBefore("go", "string", { char: { pattern: /'(?:\\.|[^'\\\r\n]){0,10}'/, greedy: !0 } }), delete Prism.languages.go["class-name"];
}