// ==UserScript==
// @name        forth-highlighter.js
// @namespace   fforum.winglion.ru
// @description highlights forth code
// @include     http://fforum.winglion.ru/*
// @require     https://code.jquery.com/jquery-3.4.1.slim.min.js
// @version     1
// @grant       none
// ==/UserScript==

(function($) {
    'use strict';
    function highlight (text) {
        if (!text) return "";
        const all_source = text.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;'); // внимание!!! в исходнике заэскейплены спецсимволы HTML
        let rest_all_source = all_source;
        let source;
        let rest_source = '';
        let latest;
        let state = false;
        let dstack = [];
        let output = [];
        let currenttags;  // стиль, который наследует слово
        let current = []; // сюда компилируется слово
        function compile(word) {
            if (word in words) {
                const t = words[word][words[word].length - 1].tags;
                if (t && !currenttags) currenttags = t;
                current.push('this["' + word.replace(/['"\\]/g, '\\$&') + '"][' + String(words[word].length - 1) + ']();');
            }
        }
        function notfound (word) {
            if (word.match(/^(0x)?[0-9a-f]+$/i)) return number;
            return ['', ''];
        }
        const words = {
            parse: [function() {
                let c = dstack[dstack.length - 1];
                c = c === ' ' ? '\\s' : c.replace(/[^\w\s]/g, '\\$&');
                const regex = new RegExp('^[^' + c + ']*', 'g');
                const match = regex.exec(rest_source);
                dstack.push(match[0]);
                output.push(rest_source.slice(0, regex.lastIndex + 1));
                rest_source = rest_source.slice(regex.lastIndex + 1, rest_source.length);
            }],
            word: [function() {
                let c = dstack[dstack.length - 1];
                c = c == ' ' ? '\\s' : s.replace(/[^\w\s]/g, '\\$&');
                const regex = new RegExp('^[' + c + ']*', 'g');
                const match = regex.exec(rest_source);
                rest_source = rest_source.slice(regex.lastIndex, rest_source.length);
                output.push(match[0]);
                words.parse[0]();
            }],
            name: [function() {
                dstack.push(' ');
                words.word[0]();
            }],
            interpret: [function() {
                do {
                    words.name[0]();
                    const word = dstack.pop().toLowerCase();
                    let xt = words[word] || false;
                    xt = xt && xt[xt.length - 1];
                    const tags = xt.tags || (!(word in words) && notfound(word));
                    const t = output.pop();
                    output.push(tags[0]);
                    output.push(t);
                    if (xt) {
                        if (xt.immediate || !state) {
                            xt();
                        } else {
                            compile(word);
                        }
                    }
                    output.push(tags[1]);
                } while (rest_source);
            }],
            refill: [function() {
                output.push(rest_source);
                source = rest_source = '';
                if (!rest_all_source) {
                    return;
                }
                const line = /^[^\n]*\n?/g;
                const match = line.exec(rest_all_source);
                source = rest_source = match[0];
                rest_all_source = rest_all_source.slice(line.lastIndex, rest_all_source.length);
            }],
            ':': [function() {
                words.name[0]();
                latest = dstack.pop().toLowerCase();
                current = [];
                state = true;
            }],
            ';': [function() {
                if (!words[latest]) words[latest] = [];
                words[latest].push(new Function(current.join('')).bind(words));
                state = false;
                words[latest][words[latest].length - 1].tags = currenttags;
                currenttags = undefined;
                current = [];
            }],
            '[': [function() {
                state = false;
            }],
            ']': [function() {
                state = true;
            }],
            bl: [function() {
                dstack.push(' ')
            }],
            immediate: [function() {
                words[latest][words[latest].length - 1].immediate = true;
            }],
            '(': [function() {
                dstack.push(')');
                words.parse[0]();
            }],
            '\\': [function() {
                words.refill[0]();
            }],
            'if': [function(){}],
            'else': [function(){}],
            then: [function(){}],
            begin: [function(){}],
            'while': [function(){}],
            repeat: [function(){}],
            until: [function(){}],
            again: [function(){}],
            'do': [function(){}],
            loop: [function(){}],
            '?do': [function(){}],
            create: [function() {
                words.name[0]();
                latest = dstack.pop();
                if (!words[latest]) words[latest] = [];
                words[latest].push(function(){});
            }],
            'does&gt;': [function(){}],
            postpone: [function() {
                words.name[0]();
                compile(dstack.pop().toLowerCase());
            }],
            'char': [function() {
                words.name[0]();
                dstack.push(dstack.pop()[0]);
            }],
            '[char]': [function() {
                words.name[0]();
                current.push('this.push[0]("' + dstack.pop()[0].replace(/[\\"]/g, "\\$&") + '");');
            }],
            push: [function(x) {
                dstack.push(x);
            }],
        };
        words[';'][0].immediate = true;
        words['('][0].immediate = true;
        words['\\'][0].immediate = true;
        words['['][0].immediate = true;
        words['does&gt;'][0].immediate = true;
        words['if'][0].immediate = true;
        words['else'][0].immediate = true;
        words['then'][0].immediate = true;
        words.begin[0].immediate = true;
        words['while'][0].immediate = true;
        words.repeat[0].immediate = true;
        words.until[0].immediate = true;
        words.again[0].immediate = true;
        words['do'][0].immediate = true;
        words.loop[0].immediate = true;
        words['?do'][0].immediate = true;
        words.postpone[0].immediate = true;
        words['[char]'][0].immediate = true;
        // в св-ве tags хранится пара тегов: начало и конец
        const literal = ['<span style="color: green;">', '</span>'];
        const define = ['<span style="color: darkorange;">', '</span>'];
        const comment = ['<span style="color: gray;">', '</span>'];
        const control = ['<span style="color: blue;">', '</span>'];
        const number = ['<span style="color: red;">', '</span>'];
        words.parse[0].tags = literal;
        words.word[0].tags = literal;
        words.name[0].tags = literal;
        words[':'][0].tags = define;
        words[';'][0].tags = define;
        words.create[0].tags = define;
        words['does&gt;'][0].tags = define;
        words['('][0].tags = comment;
        words['\\'][0].tags = comment;
        words['['][0].tags = ['<i>', ''];
        words[']'][0].tags = ['', '</i>'];
        words['if'][0].tags = control;
        words['else'][0].tags = control;
        words['then'][0].tags = control;
        words.begin[0].tags = control;
        words['while'][0].tags = control;
        words.repeat[0].tags = control;
        words.until[0].tags = control;
        words.again[0].tags = control;
        words['do'][0].tags = control;
        words.loop[0].tags = control;
        words['?do'][0].tags = control;
        words.postpone[0].tags = literal;
        words['[char]'][0].tags = literal;
        function e(s) {
            source = rest_source = s;
            words.interpret[0]();
            output = [];
            dstack = [];
        }
        e(": ' name ; : ['] ' ; immediate");
        e(': "  [char] " parse ; immediate');
        words['."'] = words['c"'] = words['s"'] = words['"'];
        e(': .(  [char] ) parse ; immediate');
        e(': constant create ; : variable create ; : value create ; : vect create ; : ->vect create ; : defer create ; : vocabulary create ;');
        e(': case postpone if ; immediate : of postpone if ; immediate : endof postpone if ; immediate : endcase postpone if ; immediate : exit postpone if ; immediate');
        e(': code  : ;');
        e(': end-code  postpone ; ; immediate');
        function run () {
            do {
                words.refill[0]();
                words.interpret[0]();
            } while (rest_all_source);
        }
        try {
            run();
        } catch (e) {
            console.log(e);
        }
        return output.join('').replace(/\n/g, '<br>');
    }

    $('.codecontent').each(function(){
        const code = $(this)[0];
        code.setAttribute('style', 'color: black; font-size: 12pt; font-style: bold;');
        const src = code.innerText;
        try {
            code.innerHTML = highlight(src);
        } catch (e) {
            console.log(e);
        }
        try {
            $(code).append('<div><button>оригинал</button></div>');
            const t = $(code).children('div');
            t.children('button').bind('click', () => t.children('div').css('display', 'block'))
            t.append('<div></div>');
            t.children('div').css('display', 'none')[0].innerText = src;
        } catch (e) {
            console.log(e);
        }
    });
})($);