Difference between revisions of "MediaWiki:Gadget-DotsSyntaxHighlighter.js"

//Syntax highlighter with various advantages
//See [[User:Remember the dot/Syntax highlighter]] for more information
 
(function () {
    "use strict";
 
    //variables that are preserved between function calls
    var wgAction = mw.config.get("wgAction");
    var wgPageContentModel = mw.config.get("wgPageContentModel");
    var wgUserLanguage = mw.config.get("wgUserLanguage");
    var textboxContainer;
    var wpTextbox0;
    var wpTextbox1;
    var syntaxStyleTextNode;
    var lastText;
    var maxSpanNumber = -1; //the number of the last span available, used to tell if creating additional spans is necessary
    var highlightSyntaxIfNeededIntervalID;
 
    /* Define context-specific regexes, one for every common token that ends the
       current context.
 
       An attempt has been made to search for the most common syntaxes first,
       thus maximizing performance. Syntaxes that begin with the same character
       are searched for at the same time.
 
       Wiki syntaxes from most common to least common:
           [[internal link]] [http:// named external link]
           {{template}} {{{template parameter}}} {| table |}
           <tag> <!-- comment -->
           http:// bare external link
           =Heading= * unordered list # ordered list : indent ; small heading  pre ---- horizontal line
           ''italic'' '''bold'''
           three tildes username four tildes signature five tildes timestamp
           &entity;
 
       The tag-matching regex follows the XML standard closely so that users
       won't feel like they have to escape sequences that MediaWiki will never
       consider to be tags.
 
       Only entities for characters which need to be escaped or cannot be
       unambiguously represented in a monospace font are highlighted, such as
       Greek letters that strongly resemble Latin letters. Use of other entities
       is discouraged as a matter of style. For the same reasons, numeric
       entities should be in hexadecimal (giving character codes in decimal only
       adds confusion).
 
       Flags: g for global search, m for make ^ match the beginning of each line
       and $ the end of each line
    */
    var breakerRegexBase = "\\[(?:\\[|(?:https?:|ftp:)?//|mailto:)|\\{(?:\\{\\{?|\\|)|<(?:[:A-Z_a-z\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u02FF\u0370-\u037D\u037F-\u1FFF\u200C\u200D\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-\uFFFD][:\\w\u00C0-\u00D6\u00D8-\u00F6\u00F8-\u02FF\u0370-\u037D\u037F-\u1FFF\u200C\u200D\u2070-\u218F\u2C00-\u2FEF\u3001-\uD7FF\uF900-\uFDCF\uFDF0-\uFFFD-\\.\u00B7\u0300-\u036F\u203F-\u203F-\u2040]*(?=/?>| )|!--[^]*?-->)|(?:https?://|ftp://|mailto:)[^\\s\"<>[\\]{-}]*[^\\s\",\\.:;<>[\\]{-}]|^(?:=|[*#:;]+|-{4,})|\\\\'\\\\'(?:\\\\')?|&(?:(?:n(?:bsp|dash)|m(?:dash|inus)|lt|e[mn]sp|thinsp|amp|quot|gt|shy|zwn?j|lrm|rlm|Alpha|Beta|Epsilon|Zeta|Eta|Iota|Kappa|[Mm]u|micro|Nu|[Oo]micron|[Rr]ho|Tau|Upsilon|Chi)|#x[0-9a-fA-F]+);|~{3,5}";
    function breakerRegexWithPrefix(prefix)
    {
        //the stop token has to be at the beginning of the regex so that it takes precedence over substrings of itself.
        //suck up newlines into the end token to avoid creating spans with nothing but newlines in them
        return new RegExp("(" + prefix + ")\n*|" + breakerRegexBase, "gm");
    }
    var defaultBreakerRegex           = new RegExp(breakerRegexBase, "gm");
    var wikilinkBreakerRegex          = breakerRegexWithPrefix("]][a-zA-Z]*");
    var namedExternalLinkBreakerRegex = breakerRegexWithPrefix("]");
    var parameterBreakerRegex         = breakerRegexWithPrefix("}}}");
    var templateBreakerRegex          = breakerRegexWithPrefix("}}");
    var tableBreakerRegex             = breakerRegexWithPrefix("\\|}");
    var headingBreakerRegex           = breakerRegexWithPrefix("\n");
    var tagBreakerRegexCache          = {};
 
    //browser workaround triggers
    var trident = ($.client.profile().layout == "trident");
 
    function highlightSyntax()
    {
        lastText = wpTextbox1.value;
        /* Backslashes and apostrophes are CSS-escaped at the beginning and all
           parsing regexes and functions are designed to match. On the other hand,
           newlines are not escaped until written so that in the regexes ^ and $
           work for both newlines and the beginning or end of the string. */
        var text = lastText.replace(/['\\]/g, "\\$&") + "\n"; //add a newline to fix scrolling and parsing issues
        var i = 0; //the location of the parser as it goes through var text
 
        var css = "";
        var spanNumber = 0;
        var lastColor;
        var before = true;
 
        /* Highlighting bold or italic markup presents a special challenge
           because the actual MediaWiki parser uses multiple passes to determine
           which ticks represent start tags and which represent end tags.
           Because that would be too slow for us here, we instead keep track of
           what kinds of unclosed opening ticks have been encountered and use
           that to make a good guess as to whether the next ticks encountered
           are an opening tag or a closing tag.
 
           The major downsides to this method are that '''apostrophe italic''
           and ''italic apostrophe''' are not highlighted correctly, and bold
           and italic are both highlighted in the same color. */
        var assumedBold = false;
        var assumedItalic = false;
 
        //writes text into to-be-created span elements of wpTextbox0 using :before and :after pseudo-elements
        //both :before and :after are used because using two pseudo-elements per span is significantly faster than doubling the number of spans required
        function writeText(text, color)
        {
            //no need to use another span if using the same color
            if (color != lastColor)
            {
                //whitespace is omitted in the hope of increasing performance
                css += "'}#s" + spanNumber; //spans will be created with IDs s0 through sN
                if (before)
                {
                    css += ":before{";
                    before = false;
                }
                else
                {
                    css += ":after{";
                    before = true;
                    ++spanNumber;
                }
                if (color)
                {
                    //"background-color" is 6 characters longer than "background" but the browser processes it faster
                    css += "background-color:" + color + ";";
                }
                css += "content:'";
                lastColor = color;
            }
            css += text;
        }
 
        function highlightBlock(color, breakerRegex)
        {
            var match;
 
            for (breakerRegex.lastIndex = i; match = breakerRegex.exec(text); breakerRegex.lastIndex = i)
            {
                if (match[1])
                {
                    //end token found
                    writeText(text.substring(i, breakerRegex.lastIndex), color);
                    i = breakerRegex.lastIndex;
                    return;
                }
 
                var endIndexOfLastColor = breakerRegex.lastIndex - match[0].length;
                if (i < endIndexOfLastColor) //avoid calling writeText with text == "" to improve performance
                {
                    writeText(text.substring(i, endIndexOfLastColor), color);
                }
 
                i = breakerRegex.lastIndex;
 
                switch (match[0].charAt(0)) //cases in this switch should be arranged from most common to least common
                {
                    case "[":
                        if (match[0].charAt(1) == "[")
                        {
                            //wikilink
                            writeText("[[", syntaxHighlighterConfig.wikilinkColor || color);
                            highlightBlock(syntaxHighlighterConfig.wikilinkColor || color, wikilinkBreakerRegex);
                        }
                        else
                        {
                            //named external link
                            writeText(match[0], syntaxHighlighterConfig.externalLinkColor || color);
                            highlightBlock(syntaxHighlighterConfig.externalLinkColor || color, namedExternalLinkBreakerRegex);
                        }
                        break;
                    case "{":
                        if (match[0].charAt(1) == "{")
                        {
                            if (match[0].length == 3)
                            {
                                //parameter
                                writeText("{{{", syntaxHighlighterConfig.parameterColor || color);
                                highlightBlock(syntaxHighlighterConfig.parameterColor || color, parameterBreakerRegex);
                            }
                            else
                            {
                                //template
                                writeText("{{", syntaxHighlighterConfig.templateColor || color);
                                highlightBlock(syntaxHighlighterConfig.templateColor || color, templateBreakerRegex);
                            }
                        }
                        else //|
                        {
                            //table
                            writeText("{|", syntaxHighlighterConfig.tableColor || color);
                            highlightBlock(syntaxHighlighterConfig.tableColor || color, tableBreakerRegex);
                        }
                        break;
                    case "<":
                        if (match[0].charAt(1) == "!")
                        {
                            //comment tag
                            writeText(match[0], syntaxHighlighterConfig.commentColor || color);
                            break;
                        }
                        else
                        {
                            //some other kind of tag, search for its end
                            //the search is made easier because XML attributes may not contain the character ">"
                            var tagEnd = text.indexOf(">", i) + 1;
                            if (tagEnd == 0)
                            {
                                //not a tag, just a "<" with some text after it
                                writeText("<", color);
                                i = i - match[0].length + 1;
                                break;
                            }
 
                            if (text.charAt(tagEnd - 2) == "/")
                            {
                                //empty tag
                                writeText(text.substring(i - match[0].length, tagEnd), syntaxHighlighterConfig.tagColor || color);
                                i = tagEnd;
                            }
                            else
                            {
                                var tagName = match[0].substring(1);
 
                                //again, cases are ordered from most common to least common
                                if (/^(?:nowiki|pre|math|syntaxhighlight|source|timeline|hiero)$/.test(tagName))
                                {
                                    //tag that can contain only plain text
                                    var stopAfter = "</" + tagName + ">";
                                    var endIndex = text.indexOf(stopAfter, i);
                                    if (endIndex == -1)
                                    {
                                        endIndex = text.length;
                                    }
                                    else
                                    {
                                        endIndex += stopAfter.length;
                                    }
                                    writeText(text.substring(i - match[0].length, endIndex), syntaxHighlighterConfig.tagColor || color);
                                    i = endIndex;
                                }
                                else
                                {
                                    //ordinary tag
                                    writeText(text.substring(i - match[0].length, tagEnd), syntaxHighlighterConfig.tagColor || color);
                                    i = tagEnd;
                                    if (!tagBreakerRegexCache[tagName])
                                    {
                                        tagBreakerRegexCache[tagName] = breakerRegexWithPrefix("</" + tagName + ">");
                                    }
                                    highlightBlock(syntaxHighlighterConfig.tagColor || color, tagBreakerRegexCache[tagName]);
                                }
                            }
                        }
                        break;
                    case "h":
                    case "f":
                    case "m":
                        //bare external link
                        writeText(match[0], syntaxHighlighterConfig.externalLinkColor || color);
                        break;
                    case "=":
                        if (/[^=]=+$/.test(text.substring(i, text.indexOf("\n", i)))) //the line begins and ends with an equals sign and has something else in the middle
                        {
                            //heading
                            writeText("=", syntaxHighlighterConfig.headingColor || color);
                            highlightBlock(syntaxHighlighterConfig.headingColor || color, headingBreakerRegex);
                        }
                        else
                        {
                            writeText("=", color); //move on, process this line as regular wikitext
                        }
                        break;
                    case "*":
                    case "#":
                    case ":":
                        //unordered list, ordered list, indent, small heading
                        //just highlight the marker
                        writeText(match[0], syntaxHighlighterConfig.listOrIndentColor || color);
                        break;
                    case ";":
                        //small heading
                        writeText(";", syntaxHighlighterConfig.headingColor || color);
                        highlightBlock(syntaxHighlighterConfig.headingColor || color, headingBreakerRegex);
                        break;
                    case "-":
                        //horizontal line
                        writeText(match[0], syntaxHighlighterConfig.hrColor || color);
                        break;
                    case "\\":
                        writeText(match[0], syntaxHighlighterConfig.boldOrItalicColor || color);
                        if (match[0].length == 6)
                        {
                            //bold
                            if (assumedBold)
                            {
                                //end tag
                                assumedBold = false;
                                return;
                            }
                            else
                            {
                                //start tag
                                assumedBold = true;
                                highlightBlock(syntaxHighlighterConfig.boldOrItalicColor || color, defaultBreakerRegex);
                            }
                        }
                        else
                        {
                            //italic
                            if (assumedItalic)
                            {
                                //end tag
                                assumedItalic = false;
                                return;
                            }
                            else
                            {
                                //start tag
                                assumedItalic = true;
                                highlightBlock(syntaxHighlighterConfig.boldOrItalicColor || color, defaultBreakerRegex);
                            }
                        }
                        break;
                    case "&":
                        //entity
                        writeText(match[0], syntaxHighlighterConfig.entityColor || color);
                        break;
                    case "~":
                        //username, signature, timestamp
                        writeText(match[0], syntaxHighlighterConfig.signatureColor || color);
                }
            }
        }
 
 
        //start!
        var startTime = Date.now();
        highlightBlock("", defaultBreakerRegex);
 
        //output the leftovers (if any) to make sure whitespace etc. matches
        if (i < text.length)
        {
            writeText(text.substring(i), "");
        }
 
        //do we have enough span elements to match the generated CSS?
        while (maxSpanNumber < spanNumber)
        {
            wpTextbox0.appendChild(document.createElement("span")).id = "s" + ++maxSpanNumber;
        }
 
        /* finish CSS: move the extra '} from the beginning to the end and CSS-
           escape newlines. CSS ignores the space after the hex code of the
           escaped character */
        syntaxStyleTextNode.nodeValue = css.substring(2).replace(/\n/g, "\\A ") + "'}";
 
        //if highlighting took too long, disable it.
        var endTime = Date.now();
        /*if (typeof(bestTime) == "undefined")
        {
            window.bestTime = 10000;
            highlightSyntaxIfNeededIntervalID = setInterval(highlightSyntax, 250);
        }
        else
        {
            if (endTime - startTime < bestTime)
            {
                bestTime = endTime - startTime;
                document.title = bestTime;
            }
        }//*/
        if (endTime - startTime > syntaxHighlighterConfig.timeout)
        {
            clearInterval(highlightSyntaxIfNeededIntervalID);
            syntaxStyleTextNode.nodeValue = "";
            wpTextbox1.removeEventListener("input", highlightSyntax);
 
            var errorMessage = {};
            errorMessage["ca"] = "S'ha desactivat el remarcar de sintaxi en aquesta pàgina perquè ha tardat massa. El temps màxim permès per a remarcar és $1ms, i el teu ordinador ha trigat $2ms. Prova tancar algunes pestanyes i programes i fer clic en \"Mostra la previsualització\" o \"Mostra els canvis\". Si no funciona això, prova altre navegador web, i si això no funciona, prova un ordinador més ràpid.";
            errorMessage["de"] = "Die Syntaxhervorhebung wurde auf dieser Seite deaktiviert, da diese zu lange gedauert hat. Die maximal erlaubte Zeit zur Hervorhebung beträgt $1ms und dein Computer benötigte $2ms. Versuche einige Tabs und Programme zu schließen und klicke \"Vorschau zeigen\" oder \"Änderungen zeigen\". Wenn das nicht funktioniert, probiere einen anderen Webbrowser und wenn immer noch nicht, probiere einen schnelleren Computer.";
            errorMessage["en"] = "Syntax highlighting on this page was disabled because it took too long. The maximum allowed highlighting time is $1ms, and your computer took $2ms. Try closing some tabs and programs and clicking \"Show preview\" or \"Show changes\". If that doesn't work, try a different web browser, and if that doesn't work, try a faster computer.";
            errorMessage["es"] = "Se desactivó el resaltar de sintaxis en esta página porque tardó demasiado. El tiempo máximum permitido para resaltar es $1ms, y tu ordenador tardó $2ms. Prueba cerrar algunas pestañas y programas y hacer clic en \"Mostrar previsualización\" o \"Mostrar cambios\". Si no funciona esto, prueba otro navegador web, y si eso no funciona, prueba un ordenador más rápido.";
            errorMessage["io"] = "Sintaxo-hailaitar en ca pagino esis nekapabligata pro ke konsumis tro multa tempo. La maxima permisata hailaitala tempo es $1ms, e tua ordinatro konsumis $2ms. Probez klozar kelka tabi e programi e kliktar \"Previdar\" o \"Montrez chanji\". Se to ne funcionas, probez altra brauzero, e se to ne funcionas, probez plu rapida ordinatro.";
            errorMessage["pt"] = "O marcador de sintaxe foi desativado nesta pagina porque demorou demais. O tempo máximo permitido para marcar e $1ms, e seu computador demorou $2ms. Tenta sair de alguns programas e clique em \"Mostrar previsão\" ou \"Mostrar alterações\". Se isso não funciona, tenta usar uma outra navegador web, e se ainda não funciona, procura um computador mais rápido.";
 
            errorMessage = errorMessage[wgUserLanguage] || errorMessage[wgUserLanguage.substring(0, wgUserLanguage.indexOf("-"))] || errorMessage["en"];
 
            wpTextbox1.style.backgroundColor = "";
            wpTextbox1.style.position = "";
            wpTextbox0.style.color = "red";
            wpTextbox0.style.fontFamily = "";
            wpTextbox0.style.fontWeight = "bold";
            wpTextbox0.style.height = "";
 
            var range = document.createRange();
            range.selectNode(wpTextbox0); //chrome can't live without this
            wpTextbox0.appendChild(range.createContextualFragment(errorMessage.replace("$1", syntaxHighlighterConfig.timeout).replace("$2", endTime - startTime)));
        }
    }
 
    function syncScrollX()
    {
        wpTextbox0.scrollLeft = wpTextbox1.scrollLeft;
    }
 
    function syncScrollY()
    {
        wpTextbox0.scrollTop = wpTextbox1.scrollTop;
    }
 
    //this function runs once every 500ms to detect changes to wpTextbox1's text that the input event does not catch
    //this happens when another script changes the text without knowing that the syntax highlighter needs to be informed
    function highlightSyntaxIfNeeded()
    {
        if (wpTextbox1.value != lastText)
        {
            highlightSyntax();
        }
        if (wpTextbox1.scrollLeft != wpTextbox0.scrollLeft)
        {
            syncScrollX();
        }
        if (wpTextbox1.scrollTop != wpTextbox0.scrollTop)
        {
            syncScrollY();
        }
    }
 
    function setup()
    {
        function configureColor(parameterName, hardcodedFallback)
        {
            if (syntaxHighlighterConfig[parameterName] == "normal")
            {
                syntaxHighlighterConfig[parameterName] = hardcodedFallback;
            }
            else if (typeof(syntaxHighlighterConfig[parameterName]) != "undefined")
            {
                return;
            }
            else if (typeof(syntaxHighlighterConfig.defaultColor) != "undefined")
            {
                syntaxHighlighterConfig[parameterName] = syntaxHighlighterConfig.defaultColor;
            }
            else
            {
                syntaxHighlighterConfig[parameterName] = hardcodedFallback;
            }
        }
 
        window.syntaxHighlighterConfig = window.syntaxHighlighterConfig || {};
 
        //use 3-digit colors instead of 6-digit colors for performance
        configureColor("boldOrItalicColor",  "#EEE"); //gray
        configureColor("commentColor",       "#EFE"); //green
        configureColor("entityColor",        "#DFD"); //green
        configureColor("externalLinkColor",  "#EFF"); //cyan
        configureColor("headingColor",       "#EEE"); //gray
        configureColor("hrColor",            "#EEE"); //gray
        configureColor("listOrIndentColor",  "#EFE"); //green
        configureColor("parameterColor",     "#FC6"); //orange
        configureColor("signatureColor",     "#FC6"); //orange
        configureColor("tagColor",           "#FEF"); //pink
        configureColor("tableColor",         "#FFC"); //yellow
        configureColor("templateColor",      "#FFC"); //yellow
        configureColor("wikilinkColor",      "#EEF"); //blue
 
        syntaxHighlighterConfig.timeout = syntaxHighlighterConfig.timeout || 100;
 
        textboxContainer = document.createElement("div");
        wpTextbox0 = document.createElement("div");
        wpTextbox1 = document.getElementById("wpTextbox1");
 
        var syntaxStyleElement = document.createElement("style");
        syntaxStyleElement.type = "text/css";
        syntaxStyleTextNode = syntaxStyleElement.appendChild(document.createTextNode(""));
 
        //the styling of the textbox and the background div must be kept very similar
        var wpTextbox1Style = window.getComputedStyle(wpTextbox1);
        var scrollTop = wpTextbox1.scrollTop;
        var focus = (document.activeElement == wpTextbox1);
 
        wpTextbox0.style.backgroundColor = wpTextbox1Style.backgroundColor;
        wpTextbox0.style.border          = "1px solid transparent";
        wpTextbox0.style.boxSizing       = "border-box";
        wpTextbox0.style.color           = "transparent"; //makes it look just a little bit smoother
        wpTextbox0.style.direction       = wpTextbox1Style.direction; //because your UI language set in Preferences may have a different direction than the edit box
        wpTextbox0.style.fontFamily      = wpTextbox1Style.fontFamily;
        wpTextbox0.style.fontSize        = wpTextbox1Style.fontSize;
        wpTextbox0.style.lineHeight      = "normal";
        wpTextbox0.style.overflowX       = "auto";
        wpTextbox0.style.overflowY       = "scroll";
        wpTextbox0.style.tabSize         = wpTextbox1Style.tabSize;
        wpTextbox0.style.whiteSpace      = "pre-wrap";
        wpTextbox0.style.width           = "100%";
        wpTextbox0.style.wordWrap        = "normal"; //see below
 
        wpTextbox1.style.backgroundColor = "transparent";
        wpTextbox1.style.border          = "1px inset gray";
        wpTextbox1.style.boxSizing       = "border-box";
        wpTextbox1.style.lineHeight      = "normal";
        wpTextbox1.style.left            = "0";
        wpTextbox1.style.margin          = "0"; //firefox wants to put a 1px margin on the top and bottom of the textbox, which throws it out of alignment with wpTextbox0
        wpTextbox1.style.overflowX       = "auto";
        wpTextbox1.style.overflowY       = "scroll";
        wpTextbox1.style.padding         = "0";
        wpTextbox1.style.position        = "absolute";
        wpTextbox1.style.resize          = "none";
        wpTextbox1.style.top             = "0";
        wpTextbox1.style.width           = "100%";
        wpTextbox1.style.wordWrap        = "normal"; //overall more visually appealing
 
        //lock both heights to pixel values so that the browser zoom feature works better
        wpTextbox0.style.height          = wpTextbox1.offsetHeight + "px";
        wpTextbox1.style.height          = wpTextbox0.style.height;
 
        textboxContainer.style.position = "relative";
        wpTextbox1.parentNode.insertBefore(textboxContainer, wpTextbox1);
        textboxContainer.appendChild(wpTextbox1);
        textboxContainer.appendChild(wpTextbox0);
 
        //changing the parent resets scrollTop to 0 and removes focus, so we have to bring that back
        wpTextbox0.scrollTop = scrollTop;
        wpTextbox1.scrollTop = scrollTop;
        if (focus) wpTextbox1.focus();
 
        //fix drop-downs in editing toolbar
        $('.tool-select *').css({zIndex: 5});
 
        document.head.appendChild(syntaxStyleElement);
 
        wpTextbox1.addEventListener("input", highlightSyntax);
        wpTextbox1.addEventListener("scroll", syncScrollX);
        wpTextbox1.addEventListener("scroll", syncScrollY);
        highlightSyntaxIfNeededIntervalID = setInterval(highlightSyntaxIfNeeded, 500);
        highlightSyntax();
    }
 
    function queueSetup()
    {
        setTimeout(setup, 0);
    }
 
 
    //enable the highlighter only when editing wikitext pages
    //in the future a separate parser could be added for CSS and JS pages
    //blacklist Internet Explorer, it's just too broken
    if ((wgAction == "edit" || wgAction == "submit") && wgPageContentModel == "wikitext" && !trident)
    {
        /* The highlighter has to run after any other script (such as the
           editing toolbar) that reparents wpTextbox1. We make sure that
           everything else has run by waiting for the page to completely load
           and then adding a call to the setup function to the end of the event
           queue, so that the setup function runs after any other triggers set
           on the load event. */
        if (document.readyState == "complete")
        {
            queueSetup();
        }
        else
        {
            $(window).load(queueSetup);
        }
    }
})();