// Copyright (C) 2006 Google Inc. // // Licensed under the Apache License, Version 2.0 (the “License”); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an “AS IS” BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License.

/**

* @fileoverview
* some functions for browser-side pretty printing of code contained in html.
*
* <p>
* For a fairly comprehensive set of languages see the
* <a href="http://google-code-prettify.googlecode.com/svn/trunk/README.html#langs">README</a>
* file that came with this source.  At a minimum, the lexer should work on a
* number of languages including C and friends, Java, Python, Bash, SQL, HTML,
* XML, CSS, Javascript, and Makefiles.  It works passably on Ruby, PHP and Awk
* and a subset of Perl, but, because of commenting conventions, doesn't work on
* Smalltalk, Lisp-like, or CAML-like languages without an explicit lang class.
* <p>
* Usage: <ol>
* <li> include this source file in an html page via
*   {@code <script type="text/javascript" src="/path/to/prettify.js"></script>}
* <li> define style rules.  See the example page for examples.
* <li> mark the {@code <pre>} and {@code <code>} tags in your source with
*    {@code class=prettyprint.}
*    You can also use the (html deprecated) {@code <xmp>} tag, but the pretty
*    printer needs to do more substantial DOM manipulations to support that, so
*    some css styles may not be preserved.
* </ol>
* That's it.  I wanted to keep the API as simple as possible, so there's no
* need to specify which language the code is in, but if you wish, you can add
* another class to the {@code <pre>} or {@code <code>} element to specify the
* language, as in {@code <pre class="prettyprint lang-java">}.  Any class that
* starts with "lang-" followed by a file extension, specifies the file type.
* See the "lang-*.js" files in this directory for code that implements
* per-language file handlers.
* <p>
* Change log:<br>
* cbeust, 2006/08/22
* <blockquote>
*   Java annotations (start with "@") are now captured as literals ("lit")
* </blockquote>
* @requires console
*/

// JSLint declarations /*global console, document, navigator, setTimeout, window */

/**

* Split {@code prettyPrint} into multiple timeouts so as not to interfere with
* UI events.
* If set to {@code false}, {@code prettyPrint()} is synchronous.
*/

window = true;

(function () {

// Keyword lists for various languages.
// We use things that coerce to strings to make them compact when minified
// and to defeat aggressive optimizers that fold large string constants.
var FLOW_CONTROL_KEYWORDS = ["break,continue,do,else,for,if,return,while"];
var C_KEYWORDS = [FLOW_CONTROL_KEYWORDS,"auto,case,char,const,default," + 
    "double,enum,extern,float,goto,int,long,register,short,signed,sizeof," +
    "static,struct,switch,typedef,union,unsigned,void,volatile"];
var COMMON_KEYWORDS = [C_KEYWORDS,"catch,class,delete,false,import," +
    "new,operator,private,protected,public,this,throw,true,try,typeof"];
var CPP_KEYWORDS = [COMMON_KEYWORDS,"alignof,align_union,asm,axiom,bool," +
    "concept,concept_map,const_cast,constexpr,decltype," +
    "dynamic_cast,explicit,export,friend,inline,late_check," +
    "mutable,namespace,nullptr,reinterpret_cast,static_assert,static_cast," +
    "template,typeid,typename,using,virtual,where"];
var JAVA_KEYWORDS = [COMMON_KEYWORDS,
    "abstract,boolean,byte,extends,final,finally,implements,import," +
    "instanceof,null,native,package,strictfp,super,synchronized,throws," +
    "transient"];
var CSHARP_KEYWORDS = [JAVA_KEYWORDS,
    "as,base,by,checked,decimal,delegate,descending,dynamic,event," +
    "fixed,foreach,from,group,implicit,in,interface,internal,into,is,lock," +
    "object,out,override,orderby,params,partial,readonly,ref,sbyte,sealed," +
    "stackalloc,string,select,uint,ulong,unchecked,unsafe,ushort,var"];
var COFFEE_KEYWORDS = "all,and,by,catch,class,else,extends,false,finally," +
    "for,if,in,is,isnt,loop,new,no,not,null,of,off,on,or,return,super,then," +
    "true,try,unless,until,when,while,yes";
var JSCRIPT_KEYWORDS = [COMMON_KEYWORDS,
    "debugger,eval,export,function,get,null,set,undefined,var,with," +
    "Infinity,NaN"];
var PERL_KEYWORDS = "caller,delete,die,do,dump,elsif,eval,exit,foreach,for," +
    "goto,if,import,last,local,my,next,no,our,print,package,redo,require," +
    "sub,undef,unless,until,use,wantarray,while,BEGIN,END";
var PYTHON_KEYWORDS = [FLOW_CONTROL_KEYWORDS, "and,as,assert,class,def,del," +
    "elif,except,exec,finally,from,global,import,in,is,lambda," +
    "nonlocal,not,or,pass,print,raise,try,with,yield," +
    "False,True,None"];
var RUBY_KEYWORDS = [FLOW_CONTROL_KEYWORDS, "alias,and,begin,case,class," +
    "def,defined,elsif,end,ensure,false,in,module,next,nil,not,or,redo," +
    "rescue,retry,self,super,then,true,undef,unless,until,when,yield," +
    "BEGIN,END"];
var SH_KEYWORDS = [FLOW_CONTROL_KEYWORDS, "case,done,elif,esac,eval,fi," +
    "function,in,local,set,then,until"];
var ALL_KEYWORDS = [
    CPP_KEYWORDS, CSHARP_KEYWORDS, JSCRIPT_KEYWORDS, PERL_KEYWORDS +
    PYTHON_KEYWORDS, RUBY_KEYWORDS, SH_KEYWORDS];
var C_TYPES = /^(DIR|FILE|vector|(de|priority_)?queue|list|stack|(const_)?iterator|(multi)?(set|map)|bitset|u?(int|float)\d*)/;

// token style names.  correspond to css classes
/**
 * token style for a string literal
 * @const
 */
var PR_STRING = 'str';
/**
 * token style for a keyword
 * @const
 */
var PR_KEYWORD = 'kwd';
/**
 * token style for a comment
 * @const
 */
var PR_COMMENT = 'com';
/**
 * token style for a type
 * @const
 */
var PR_TYPE = 'typ';
/**
 * token style for a literal value.  e.g. 1, null, true.
 * @const
 */
var PR_LITERAL = 'lit';
/**
 * token style for a punctuation string.
 * @const
 */
var PR_PUNCTUATION = 'pun';
/**
 * token style for a punctuation string.
 * @const
 */
var PR_PLAIN = 'pln';

/**
 * token style for an sgml tag.
 * @const
 */
var PR_TAG = 'tag';
/**
 * token style for a markup declaration such as a DOCTYPE.
 * @const
 */
var PR_DECLARATION = 'dec';
/**
 * token style for embedded source.
 * @const
 */
var PR_SOURCE = 'src';
/**
 * token style for an sgml attribute name.
 * @const
 */
var PR_ATTRIB_NAME = 'atn';
/**
 * token style for an sgml attribute value.
 * @const
 */
var PR_ATTRIB_VALUE = 'atv';

/**
 * A class that indicates a section of markup that is not code, e.g. to allow
 * embedding of line numbers within code listings.
 * @const
 */
var PR_NOCODE = 'nocode';

/**

* A set of tokens that can precede a regular expression literal in
* javascript
* http://web.archive.org/web/20070717142515/http://www.mozilla.org/js/language/js20/rationale/syntax.html
* has the full list, but I've removed ones that might be problematic when
* seen in languages that don't support regular expression literals.
*
* <p>Specifically, I've removed any keywords that can't precede a regexp
* literal in a syntactically legal javascript program, and I've removed the
* "in" keyword since it's not a keyword in many languages, and might be used
* as a count of inches.
*
* <p>The link a above does not accurately describe EcmaScript rules since
* it fails to distinguish between (a=++/b/i) and (a++/b/i) but it works
* very well in practice.
*
* @private
* @const
*/

var REGEXP_PRECEDER_PATTERN = '(?:^^\.?|[+-]|\!|\!=|\!==|\#|\%|\%=|&|&&|&&=|&=|\(|*|*=|+=|\,|\-=|\->|\/|\/=|:|::|\;|<|<<|<<=|<=|=|==|===|>|>=|>>|>>=|>>>|>>>=|\?|\@|\[|\^|\^=|\^\^|\^\^=|\{|\||\|=|\|\||\|\|=|\~|break|case|continue|delete|do|else|finally|instanceof|return|throw|try|typeof)\s*';

// CAVEAT: this does not properly handle the case where a regular // expression immediately follows another since a regular expression may // have flags for case-sensitivity and the like. Having regexp tokens // adjacent is not valid in any language I'm aware of, so I'm punting. // TODO: maybe style special characters inside a regexp as punctuation.

/**
 * Given a group of {@link RegExp}s, returns a {@code RegExp} that globally
 * matches the union of the sets of strings matched by the input RegExp.
 * Since it matches globally, if the input strings have a start-of-input
 * anchor (/^.../), it is ignored for the purposes of unioning.
 * @param {Array.<RegExp>} regexs non multiline, non-global regexs.
 * @return {RegExp} a global regex.
 */
function combinePrefixPatterns(regexs) {
  var capturedGroupIndex = 0;

  var needToFoldCase = false;
  var ignoreCase = false;
  for (var i = 0, n = regexs.length; i < n; ++i) {
    var regex = regexs[i];
    if (regex.ignoreCase) {
      ignoreCase = true;
    } else if (/[a-z]/i.test(regex.source.replace(
                   /\\u[0-9a-f]{4}|\\x[0-9a-f]{2}|\\[^ux]/gi, ''))) {
      needToFoldCase = true;
      ignoreCase = false;
      break;
    }
  }

  var escapeCharToCodeUnit = {
    'b': 8,
    't': 9,
    'n': 0xa,
    'v': 0xb,
    'f': 0xc,
    'r': 0xd
  };

  function decodeEscape(charsetPart) {
    var cc0 = charsetPart.charCodeAt(0);
    if (cc0 !== 92 /* \\ */) {
      return cc0;
    }
    var c1 = charsetPart.charAt(1);
    cc0 = escapeCharToCodeUnit[c1];
    if (cc0) {
      return cc0;
    } else if ('0' <= c1 && c1 <= '7') {
      return parseInt(charsetPart.substring(1), 8);
    } else if (c1 === 'u' || c1 === 'x') {
      return parseInt(charsetPart.substring(2), 16);
    } else {
      return charsetPart.charCodeAt(1);
    }
  }

  function encodeEscape(charCode) {
    if (charCode < 0x20) {
      return (charCode < 0x10 ? '\\x0' : '\\x') + charCode.toString(16);
    }
    var ch = String.fromCharCode(charCode);
    if (ch === '\\' || ch === '-' || ch === '[' || ch === ']') {
      ch = '\\' + ch;
    }
    return ch;
  }

  function caseFoldCharset(charSet) {
    var charsetParts = charSet.substring(1, charSet.length - 1).match(
        new RegExp(
            '\\\\u[0-9A-Fa-f]{4}'
            + '|\\\\x[0-9A-Fa-f]{2}'
            + '|\\\\[0-3][0-7]{0,2}'
            + '|\\\\[0-7]{1,2}'
            + '|\\\\[\\s\\S]'
            + '|-'
            + '|[^-\\\\]',
            'g'));
    var groups = [];
    var ranges = [];
    var inverse = charsetParts[0] === '^';
    for (var i = inverse ? 1 : 0, n = charsetParts.length; i < n; ++i) {
      var p = charsetParts[i];
      if (/\\[bdsw]/i.test(p)) {  // Don't muck with named groups.
        groups.push(p);
      } else {
        var start = decodeEscape(p);
        var end;
        if (i + 2 < n && '-' === charsetParts[i + 1]) {
          end = decodeEscape(charsetParts[i + 2]);
          i += 2;
        } else {
          end = start;
        }
        ranges.push([start, end]);
        // If the range might intersect letters, then expand it.
        // This case handling is too simplistic.
        // It does not deal with non-latin case folding.
        // It works for latin source code identifiers though.
        if (!(end < 65 || start > 122)) {
          if (!(end < 65 || start > 90)) {
            ranges.push([Math.max(65, start) | 32, Math.min(end, 90) | 32]);
          }
          if (!(end < 97 || start > 122)) {
            ranges.push([Math.max(97, start) & ~32, Math.min(end, 122) & ~32]);
          }
        }
      }
    }

    // [[1, 10], [3, 4], [8, 12], [14, 14], [16, 16], [17, 17]]
    // -> [[1, 12], [14, 14], [16, 17]]
    ranges.sort(function (a, b) { return (a[0] - b[0]) || (b[1]  - a[1]); });
    var consolidatedRanges = [];
    var lastRange = [NaN, NaN];
    for (var i = 0; i < ranges.length; ++i) {
      var range = ranges[i];
      if (range[0] <= lastRange[1] + 1) {
        lastRange[1] = Math.max(lastRange[1], range[1]);
      } else {
        consolidatedRanges.push(lastRange = range);
      }
    }

    var out = ['['];
    if (inverse) { out.push('^'); }
    out.push.apply(out, groups);
    for (var i = 0; i < consolidatedRanges.length; ++i) {
      var range = consolidatedRanges[i];
      out.push(encodeEscape(range[0]));
      if (range[1] > range[0]) {
        if (range[1] + 1 > range[0]) { out.push('-'); }
        out.push(encodeEscape(range[1]));
      }
    }
    out.push(']');
    return out.join('');
  }

  function allowAnywhereFoldCaseAndRenumberGroups(regex) {
    // Split into character sets, escape sequences, punctuation strings
    // like ('(', '(?:', ')', '^'), and runs of characters that do not
    // include any of the above.
    var parts = regex.source.match(
        new RegExp(
            '(?:'
            + '\\[(?:[^\\x5C\\x5D]|\\\\[\\s\\S])*\\]'  // a character set
            + '|\\\\u[A-Fa-f0-9]{4}'  // a unicode escape
            + '|\\\\x[A-Fa-f0-9]{2}'  // a hex escape
            + '|\\\\[0-9]+'  // a back-reference or octal escape
            + '|\\\\[^ux0-9]'  // other escape sequence
            + '|\\(\\?[:!=]'  // start of a non-capturing group
            + '|[\\(\\)\\^]'  // start/emd of a group, or line start
            + '|[^\\x5B\\x5C\\(\\)\\^]+'  // run of other characters
            + ')',
            'g'));
    var n = parts.length;

    // Maps captured group numbers to the number they will occupy in
    // the output or to -1 if that has not been determined, or to
    // undefined if they need not be capturing in the output.
    var capturedGroups = [];

    // Walk over and identify back references to build the capturedGroups
    // mapping.
    for (var i = 0, groupIndex = 0; i < n; ++i) {
      var p = parts[i];
      if (p === '(') {
        // groups are 1-indexed, so max group index is count of '('
        ++groupIndex;
      } else if ('\\' === p.charAt(0)) {
        var decimalValue = +p.substring(1);
        if (decimalValue && decimalValue <= groupIndex) {
          capturedGroups[decimalValue] = -1;
        }
      }
    }

    // Renumber groups and reduce capturing groups to non-capturing groups
    // where possible.
    for (var i = 1; i < capturedGroups.length; ++i) {
      if (-1 === capturedGroups[i]) {
        capturedGroups[i] = ++capturedGroupIndex;
      }
    }
    for (var i = 0, groupIndex = 0; i < n; ++i) {
      var p = parts[i];
      if (p === '(') {
        ++groupIndex;
        if (capturedGroups[groupIndex] === undefined) {
          parts[i] = '(?:';
        }
      } else if ('\\' === p.charAt(0)) {
        var decimalValue = +p.substring(1);
        if (decimalValue && decimalValue <= groupIndex) {
          parts[i] = '\\' + capturedGroups[groupIndex];
        }
      }
    }

    // Remove any prefix anchors so that the output will match anywhere.
    // ^^ really does mean an anchored match though.
    for (var i = 0, groupIndex = 0; i < n; ++i) {
      if ('^' === parts[i] && '^' !== parts[i + 1]) { parts[i] = ''; }
    }

    // Expand letters to groups to handle mixing of case-sensitive and
    // case-insensitive patterns if necessary.
    if (regex.ignoreCase && needToFoldCase) {
      for (var i = 0; i < n; ++i) {
        var p = parts[i];
        var ch0 = p.charAt(0);
        if (p.length >= 2 && ch0 === '[') {
          parts[i] = caseFoldCharset(p);
        } else if (ch0 !== '\\') {
          // TODO: handle letters in numeric escapes.
          parts[i] = p.replace(
              /[a-zA-Z]/g,
              function (ch) {
                var cc = ch.charCodeAt(0);
                return '[' + String.fromCharCode(cc & ~32, cc | 32) + ']';
              });
        }
      }
    }

    return parts.join('');
  }

  var rewritten = [];
  for (var i = 0, n = regexs.length; i < n; ++i) {
    var regex = regexs[i];
    if (regex.global || regex.multiline) { throw new Error('' + regex); }
    rewritten.push(
        '(?:' + allowAnywhereFoldCaseAndRenumberGroups(regex) + ')');
  }

  return new RegExp(rewritten.join('|'), ignoreCase ? 'gi' : 'g');
}

/**
 * Split markup into a string of source code and an array mapping ranges in
 * that string to the text nodes in which they appear.
 *
 * <p>
 * The HTML DOM structure:</p>
 * <pre>
 * (Element   "p"
 *   (Element "b"
 *     (Text  "print "))       ; #1
 *   (Text    "'Hello '")      ; #2
 *   (Element "br")            ; #3
 *   (Text    "  + 'World';")) ; #4
 * </pre>
 * <p>
 * corresponds to the HTML
 * {@code <p><b>print </b>'Hello '<br>  + 'World';</p>}.</p>
 *
 * <p>
 * It will produce the output:</p>
 * <pre>
 * {
 *   sourceCode: "print 'Hello '\n  + 'World';",
 *   //                 1         2
 *   //       012345678901234 5678901234567
 *   spans: [0, #1, 6, #2, 14, #3, 15, #4]
 * }
 * </pre>
 * <p>
 * where #1 is a reference to the {@code "print "} text node above, and so
 * on for the other text nodes.
 * </p>
 *
 * <p>
 * The {@code} spans array is an array of pairs.  Even elements are the start
 * indices of substrings, and odd elements are the text nodes (or BR elements)
 * that contain the text for those substrings.
 * Substrings continue until the next index or the end of the source.
 * </p>
 *
 * @param {Node} node an HTML DOM subtree containing source-code.
 * @return {Object} source code and the text nodes in which they occur.
 */
function extractSourceSpans(node) {
  var nocode = /(?:^|\s)nocode(?:\s|$)/;

  var chunks = [];
  var length = 0;
  var spans = [];
  var k = 0;

  var whitespace;
  if (node.currentStyle) {
    whitespace = node.currentStyle.whiteSpace;
  } else if (window.getComputedStyle) {
    whitespace = document.defaultView.getComputedStyle(node, null)
        .getPropertyValue('white-space');
  }
  var isPreformatted = whitespace && 'pre' === whitespace.substring(0, 3);

  function walk(node) {
    switch (node.nodeType) {
      case 1:  // Element
        if (nocode.test(node.className)) { return; }
        for (var child = node.firstChild; child; child = child.nextSibling) {
          walk(child);
        }
        var nodeName = node.nodeName;
        if ('BR' === nodeName || 'LI' === nodeName) {
          chunks[k] = '\n';
          spans[k << 1] = length++;
          spans[(k++ << 1) | 1] = node;
        }
        break;
      case 3: case 4:  // Text
        var text = node.nodeValue;
        if (text.length) {
          if (!isPreformatted) {
            text = text.replace(/[ \t\r\n]+/g, ' ');
          } else {
            text = text.replace(/\r\n?/g, '\n');  // Normalize newlines.
          }
          // TODO: handle tabs here?
          chunks[k] = text;
          spans[k << 1] = length;
          length += text.length;
          spans[(k++ << 1) | 1] = node;
        }
        break;
    }
  }

  walk(node);

  return {
    sourceCode: chunks.join('').replace(/\n$/, ''),
    spans: spans
  };
}

/**
 * Apply the given language handler to sourceCode and add the resulting
 * decorations to out.
 * @param {number} basePos the index of sourceCode within the chunk of source
 *    whose decorations are already present on out.
 */
function appendDecorations(basePos, sourceCode, langHandler, out) {
  if (!sourceCode) { return; }
  var job = {
    sourceCode: sourceCode,
    basePos: basePos
  };
  langHandler(job);
  out.push.apply(out, job.decorations);
}

var notWs = /\S/;

/**
 * Given an element, if it contains only one child element and any text nodes
 * it contains contain only space characters, return the sole child element.
 * Otherwise returns undefined.
 * <p>
 * This is meant to return the CODE element in {@code <pre><code ...>} when
 * there is a single child element that contains all the non-space textual
 * content, but not to return anything where there are multiple child elements
 * as in {@code <pre><code>...</code><code>...</code></pre>} or when there
 * is textual content.
 */
function childContentWrapper(element) {
  var wrapper = undefined;
  for (var c = element.firstChild; c; c = c.nextSibling) {
    var type = c.nodeType;
    wrapper = (type === 1)  // Element Node
        ? (wrapper ? element : c)
        : (type === 3)  // Text Node
        ? (notWs.test(c.nodeValue) ? element : wrapper)
        : wrapper;
  }
  return wrapper === element ? undefined : wrapper;
}

/** Given triples of [style, pattern, context] returns a lexing function,
  * The lexing function interprets the patterns to find token boundaries and
  * returns a decoration list of the form
  * [index_0, style_0, index_1, style_1, ..., index_n, style_n]
  * where index_n is an index into the sourceCode, and style_n is a style
  * constant like PR_PLAIN.  index_n-1 <= index_n, and style_n-1 applies to
  * all characters in sourceCode[index_n-1:index_n].
  *
  * The stylePatterns is a list whose elements have the form
  * [style : string, pattern : RegExp, DEPRECATED, shortcut : string].
  *
  * Style is a style constant like PR_PLAIN, or can be a string of the
  * form 'lang-FOO', where FOO is a language extension describing the
  * language of the portion of the token in $1 after pattern executes.
  * E.g., if style is 'lang-lisp', and group 1 contains the text
  * '(hello (world))', then that portion of the token will be passed to the
  * registered lisp handler for formatting.
  * The text before and after group 1 will be restyled using this decorator
  * so decorators should take care that this doesn't result in infinite
  * recursion.  For example, the HTML lexer rule for SCRIPT elements looks
  * something like ['lang-js', /<[s]cript>(.+?)<\/script>/].  This may match
  * '<script>foo()<\/script>', which would cause the current decorator to
  * be called with '<script>' which would not match the same rule since
  * group 1 must not be empty, so it would be instead styled as PR_TAG by
  * the generic tag rule.  The handler registered for the 'js' extension would
  * then be called with 'foo()', and finally, the current decorator would
  * be called with '<\/script>' which would not match the original rule and
  * so the generic tag rule would identify it as a tag.
  *
  * Pattern must only match prefixes, and if it matches a prefix, then that
  * match is considered a token with the same style.
  *
  * Context is applied to the last non-whitespace, non-comment token
  * recognized.
  *
  * Shortcut is an optional string of characters, any of which, if the first
  * character, gurantee that this pattern and only this pattern matches.
  *
  * @param {Array} shortcutStylePatterns patterns that always start with
  *   a known character.  Must have a shortcut string.
  * @param {Array} fallthroughStylePatterns patterns that will be tried in
  *   order if the shortcut ones fail.  May have shortcuts.
  *
  * @return {function (Object)} a
  *   function that takes source code and returns a list of decorations.
  */
function createSimpleLexer(shortcutStylePatterns, fallthroughStylePatterns) {
  var shortcuts = {};
  var tokenizer;
  (function () {
    var allPatterns = shortcutStylePatterns.concat(fallthroughStylePatterns);
    var allRegexs = [];
    var regexKeys = {};
    for (var i = 0, n = allPatterns.length; i < n; ++i) {
      var patternParts = allPatterns[i];
      var shortcutChars = patternParts[3];
      if (shortcutChars) {
        for (var c = shortcutChars.length; --c >= 0;) {
          shortcuts[shortcutChars.charAt(c)] = patternParts;
        }
      }
      var regex = patternParts[1];
      var k = '' + regex;
      if (!regexKeys.hasOwnProperty(k)) {
        allRegexs.push(regex);
        regexKeys[k] = null;
      }
    }
    allRegexs.push(/[\0-\uffff]/);
    tokenizer = combinePrefixPatterns(allRegexs);
  })();

  var nPatterns = fallthroughStylePatterns.length;

  /**
   * Lexes job.sourceCode and produces an output array job.decorations of
   * style classes preceded by the position at which they start in
   * job.sourceCode in order.
   *
   * @param {Object} job an object like <pre>{
   *    sourceCode: {string} sourceText plain text,
   *    basePos: {int} position of job.sourceCode in the larger chunk of
   *        sourceCode.
   * }</pre>
   */
  var decorate = function (job) {
    var sourceCode = job.sourceCode, basePos = job.basePos;
    /** Even entries are positions in source in ascending order.  Odd enties
      * are style markers (e.g., PR_COMMENT) that run from that position until
      * the end.
      * @type {Array.<number|string>}
      */
    var decorations = [basePos, PR_PLAIN];
    var pos = 0;  // index into sourceCode
    var tokens = sourceCode.match(tokenizer) || [];
    var styleCache = {};

    for (var ti = 0, nTokens = tokens.length; ti < nTokens; ++ti) {
      var token = tokens[ti];
      var style = styleCache[token];
      var match = void 0;

      var isEmbedded;
      if (typeof style === 'string') {
        isEmbedded = false;
      } else {
        var patternParts = shortcuts[token.charAt(0)];
        if (patternParts) {
          match = token.match(patternParts[1]);
          style = patternParts[0];
        } else {
          for (var i = 0; i < nPatterns; ++i) {
            patternParts = fallthroughStylePatterns[i];
            match = token.match(patternParts[1]);
            if (match) {
              style = patternParts[0];
              break;
            }
          }

          if (!match) {  // make sure that we make progress
            style = PR_PLAIN;
          }
        }

        isEmbedded = style.length >= 5 && 'lang-' === style.substring(0, 5);
        if (isEmbedded && !(match && typeof match[1] === 'string')) {
          isEmbedded = false;
          style = PR_SOURCE;
        }

        if (!isEmbedded) { styleCache[token] = style; }
      }

      var tokenStart = pos;
      pos += token.length;

      if (!isEmbedded) {
        decorations.push(basePos + tokenStart, style);
      } else {  // Treat group 1 as an embedded block of source code.
        var embeddedSource = match[1];
        var embeddedSourceStart = token.indexOf(embeddedSource);
        var embeddedSourceEnd = embeddedSourceStart + embeddedSource.length;
        if (match[2]) {
          // If embeddedSource can be blank, then it would match at the
          // beginning which would cause us to infinitely recurse on the
          // entire token, so we catch the right context in match[2].
          embeddedSourceEnd = token.length - match[2].length;
          embeddedSourceStart = embeddedSourceEnd - embeddedSource.length;
        }
        var lang = style.substring(5);
        // Decorate the left of the embedded source
        appendDecorations(
            basePos + tokenStart,
            token.substring(0, embeddedSourceStart),
            decorate, decorations);
        // Decorate the embedded source
        appendDecorations(
            basePos + tokenStart + embeddedSourceStart,
            embeddedSource,
            langHandlerForExtension(lang, embeddedSource),
            decorations);
        // Decorate the right of the embedded section
        appendDecorations(
            basePos + tokenStart + embeddedSourceEnd,
            token.substring(embeddedSourceEnd),
            decorate, decorations);
      }
    }
    job.decorations = decorations;
  };
  return decorate;
}

/** returns a function that produces a list of decorations from source text.
  *
  * This code treats ", ', and ` as string delimiters, and \ as a string
  * escape.  It does not recognize perl's qq() style strings.
  * It has no special handling for double delimiter escapes as in basic, or
  * the tripled delimiters used in python, but should work on those regardless
  * although in those cases a single string literal may be broken up into
  * multiple adjacent string literals.
  *
  * It recognizes C, C++, and shell style comments.
  *
  * @param {Object} options a set of optional parameters.
  * @return {function (Object)} a function that examines the source code
  *     in the input job and builds the decoration list.
  */
function sourceDecorator(options) {
  var shortcutStylePatterns = [], fallthroughStylePatterns = [];
  if (options['tripleQuotedStrings']) {
    // '''multi-line-string''', 'single-line-string', and double-quoted
    shortcutStylePatterns.push(
        [PR_STRING,  /^(?:\'\'\'(?:[^\'\\]|\\[\s\S]|\'{1,2}(?=[^\']))*(?:\'\'\'|$)|\"\"\"(?:[^\"\\]|\\[\s\S]|\"{1,2}(?=[^\"]))*(?:\"\"\"|$)|\'(?:[^\\\']|\\[\s\S])*(?:\'|$)|\"(?:[^\\\"]|\\[\s\S])*(?:\"|$))/,
         null, '\'"']);
  } else if (options['multiLineStrings']) {
    // 'multi-line-string', "multi-line-string"
    shortcutStylePatterns.push(
        [PR_STRING,  /^(?:\'(?:[^\\\']|\\[\s\S])*(?:\'|$)|\"(?:[^\\\"]|\\[\s\S])*(?:\"|$)|\`(?:[^\\\`]|\\[\s\S])*(?:\`|$))/,
         null, '\'"`']);
  } else {
    // 'single-line-string', "single-line-string"
    shortcutStylePatterns.push(
        [PR_STRING,
         /^(?:\'(?:[^\\\'\r\n]|\\.)*(?:\'|$)|\"(?:[^\\\"\r\n]|\\.)*(?:\"|$))/,
         null, '"\'']);
  }
  if (options['verbatimStrings']) {
    // verbatim-string-literal production from the C# grammar.  See issue 93.
    fallthroughStylePatterns.push(
        [PR_STRING, /^@\"(?:[^\"]|\"\")*(?:\"|$)/, null]);
  }
  var hc = options['hashComments'];
  if (hc) {
    if (options['cStyleComments']) {
      if (hc > 1) {  // multiline hash comments
        shortcutStylePatterns.push(
            [PR_COMMENT, /^#(?:##(?:[^#]|#(?!##))*(?:###|$)|.*)/, null, '#']);
      } else {
        // Stop C preprocessor declarations at an unclosed open comment
        shortcutStylePatterns.push(
            [PR_COMMENT, /^#(?:(?:define|elif|else|endif|error|ifdef|include|ifndef|line|pragma|undef|warning)\b|[^\r\n]*)/,
             null, '#']);
      }
      fallthroughStylePatterns.push(
          [PR_STRING,
           /^<(?:(?:(?:\.\.\/)*|\/?)(?:[\w-]+(?:\/[\w-]+)+)?[\w-]+\.h|[a-z]\w*)>/,
           null]);
    } else {
      shortcutStylePatterns.push([PR_COMMENT, /^#[^\r\n]*/, null, '#']);
    }
  }
  if (options['cStyleComments']) {
    fallthroughStylePatterns.push([PR_COMMENT, /^\/\/[^\r\n]*/, null]);
    fallthroughStylePatterns.push(
        [PR_COMMENT, /^\/\*[\s\S]*?(?:\*\/|$)/, null]);
  }
  if (options['regexLiterals']) {
    /**
     * @const
     */
    var REGEX_LITERAL = (
        // A regular expression literal starts with a slash that is
        // not followed by * or / so that it is not confused with
        // comments.
        '/(?=[^/*])'
        // and then contains any number of raw characters,
        + '(?:[^/\\x5B\\x5C]'
        // escape sequences (\x5C),
        +    '|\\x5C[\\s\\S]'
        // or non-nesting character sets (\x5B\x5D);
        +    '|\\x5B(?:[^\\x5C\\x5D]|\\x5C[\\s\\S])*(?:\\x5D|$))+'
        // finally closed by a /.
        + '/');
    fallthroughStylePatterns.push(
        ['lang-regex',
         new RegExp('^' + REGEXP_PRECEDER_PATTERN + '(' + REGEX_LITERAL + ')')
         ]);
  }

  var types = options['types'];
  if (types) {
    fallthroughStylePatterns.push([PR_TYPE, types]);
  }

  var keywords = ("" + options['keywords']).replace(/^ | $/g, '');
  if (keywords.length) {
    fallthroughStylePatterns.push(
        [PR_KEYWORD,
         new RegExp('^(?:' + keywords.replace(/[\s,]+/g, '|') + ')\\b'),
         null]);
  }

  shortcutStylePatterns.push([PR_PLAIN,       /^\s+/, null, ' \r\n\t\xA0']);
  fallthroughStylePatterns.push(
      // TODO(mikesamuel): recognize non-latin letters and numerals in idents
      [PR_LITERAL,     /^@[a-z_$][a-z_$@0-9]*/i, null],
      [PR_TYPE,        /^(?:[@_]?[A-Z]+[a-z][A-Za-z_$@0-9]*|\w+_t\b)/, null],
      [PR_PLAIN,       /^[a-z_$][a-z_$@0-9]*/i, null],
      [PR_LITERAL,
       new RegExp(
           '^(?:'
           // A hex number
           + '0x[a-f0-9]+'
           // or an octal or decimal number,
           + '|(?:\\d(?:_\\d+)*\\d*(?:\\.\\d*)?|\\.\\d\\+)'
           // possibly in scientific notation
           + '(?:e[+\\-]?\\d+)?'
           + ')'
           // with an optional modifier like UL for unsigned long
           + '[a-z]*', 'i'),
       null, '0123456789'],
      // Don't treat escaped quotes in bash as starting strings.  See issue 144.
      [PR_PLAIN,       /^\\[\s\S]?/, null],
      [PR_PUNCTUATION, /^.[^\s\w\.$@\'\"\`\/\#\\]*/, null]);

  return createSimpleLexer(shortcutStylePatterns, fallthroughStylePatterns);
}

var decorateSource = sourceDecorator({
      'keywords': ALL_KEYWORDS,
      'hashComments': true,
      'cStyleComments': true,
      'multiLineStrings': true,
      'regexLiterals': true
    });

/**
 * Given a DOM subtree, wraps it in a list, and puts each line into its own
 * list item.
 *
 * @param {Node} node modified in place.  Its content is pulled into an
 *     HTMLOListElement, and each line is moved into a separate list item.
 *     This requires cloning elements, so the input might not have unique
 *     IDs after numbering.
 */
function numberLines(node, opt_startLineNum) {
  var nocode = /(?:^|\s)nocode(?:\s|$)/;
  var lineBreak = /\r\n?|\n/;

  var document = node.ownerDocument;

  var whitespace;
  if (node.currentStyle) {
    whitespace = node.currentStyle.whiteSpace;
  } else if (window.getComputedStyle) {
    whitespace = document.defaultView.getComputedStyle(node, null)
        .getPropertyValue('white-space');
  }
  // If it's preformatted, then we need to split lines on line breaks
  // in addition to <BR>s.
  var isPreformatted = whitespace && 'pre' === whitespace.substring(0, 3);

  var li = document.createElement('LI');
  while (node.firstChild) {
    li.appendChild(node.firstChild);
  }
  // An array of lines.  We split below, so this is initialized to one
  // un-split line.
  var listItems = [li];

  function walk(node) {
    switch (node.nodeType) {
      case 1:  // Element
        if (nocode.test(node.className)) { break; }
        if ('BR' === node.nodeName) {
          breakAfter(node);
          // Discard the <BR> since it is now flush against a </LI>.
          if (node.parentNode) {
            node.parentNode.removeChild(node);
          }
        } else {
          for (var child = node.firstChild; child; child = child.nextSibling) {
            walk(child);
          }
        }
        break;
      case 3: case 4:  // Text
        if (isPreformatted) {
          var text = node.nodeValue;
          var match = text.match(lineBreak);
          if (match) {
            var firstLine = text.substring(0, match.index);
            node.nodeValue = firstLine;
            var tail = text.substring(match.index + match[0].length);
            if (tail) {
              var parent = node.parentNode;
              parent.insertBefore(
                  document.createTextNode(tail), node.nextSibling);
            }
            breakAfter(node);
            if (!firstLine) {
              // Don't leave blank text nodes in the DOM.
              node.parentNode.removeChild(node);
            }
          }
        }
        break;
    }
  }

  // Split a line after the given node.
  function breakAfter(lineEndNode) {
    // If there's nothing to the right, then we can skip ending the line
    // here, and move root-wards since splitting just before an end-tag
    // would require us to create a bunch of empty copies.
    while (!lineEndNode.nextSibling) {
      lineEndNode = lineEndNode.parentNode;
      if (!lineEndNode) { return; }
    }

    function breakLeftOf(limit, copy) {
      // Clone shallowly if this node needs to be on both sides of the break.
      var rightSide = copy ? limit.cloneNode(false) : limit;
      var parent = limit.parentNode;
      if (parent) {
        // We clone the parent chain.
        // This helps us resurrect important styling elements that cross lines.
        // E.g. in <i>Foo<br>Bar</i>
        // should be rewritten to <li><i>Foo</i></li><li><i>Bar</i></li>.
        var parentClone = breakLeftOf(parent, 1);
        // Move the clone and everything to the right of the original
        // onto the cloned parent.
        var next = limit.nextSibling;
        parentClone.appendChild(rightSide);
        for (var sibling = next; sibling; sibling = next) {
          next = sibling.nextSibling;
          parentClone.appendChild(sibling);
        }
      }
      return rightSide;
    }

    var copiedListItem = breakLeftOf(lineEndNode.nextSibling, 0);

    // Walk the parent chain until we reach an unattached LI.
    for (var parent;
         // Check nodeType since IE invents document fragments.
         (parent = copiedListItem.parentNode) && parent.nodeType === 1;) {
      copiedListItem = parent;
    }
    // Put it on the list of lines for later processing.
    listItems.push(copiedListItem);
  }

  // Split lines while there are lines left to split.
  for (var i = 0;  // Number of lines that have been split so far.
       i < listItems.length;  // length updated by breakAfter calls.
       ++i) {
    walk(listItems[i]);
  }

  // Make sure numeric indices show correctly.
  if (opt_startLineNum === (opt_startLineNum|0)) {
    listItems[0].setAttribute('value', opt_startLineNum);
  }

  var ol = document.createElement('OL');
  ol.className = 'linenums';
  var offset = Math.max(0, ((opt_startLineNum - 1 /* zero index */)) | 0) || 0;
  for (var i = 0, n = listItems.length; i < n; ++i) {
    li = listItems[i];
    // Stick a class on the LIs so that stylesheets can
    // color odd/even rows, or any other row pattern that
    // is co-prime with 10.
    li.className = 'L' + ((i + offset) % 10);
    if (!li.firstChild) {
      li.appendChild(document.createTextNode('\xA0'));
    }
    ol.appendChild(li);
  }

  node.appendChild(ol);
}

/**
 * Breaks {@code job.sourceCode} around style boundaries in
 * {@code job.decorations} and modifies {@code job.sourceNode} in place.
 * @param {Object} job like <pre>{
 *    sourceCode: {string} source as plain text,
 *    spans: {Array.<number|Node>} alternating span start indices into source
 *       and the text node or element (e.g. {@code <BR>}) corresponding to that
 *       span.
 *    decorations: {Array.<number|string} an array of style classes preceded
 *       by the position at which they start in job.sourceCode in order
 * }</pre>
 * @private
 */
function recombineTagsAndDecorations(job) {
  var isIE = /\bMSIE\b/.test(navigator.userAgent);
  var newlineRe = /\n/g;

  var source = job.sourceCode;
  var sourceLength = source.length;
  // Index into source after the last code-unit recombined.
  var sourceIndex = 0;

  var spans = job.spans;
  var nSpans = spans.length;
  // Index into spans after the last span which ends at or before sourceIndex.
  var spanIndex = 0;

  var decorations = job.decorations;
  var nDecorations = decorations.length;
  // Index into decorations after the last decoration which ends at or before
  // sourceIndex.
  var decorationIndex = 0;

  // Remove all zero-length decorations.
  decorations[nDecorations] = sourceLength;
  var decPos, i;
  for (i = decPos = 0; i < nDecorations;) {
    if (decorations[i] !== decorations[i + 2]) {
      decorations[decPos++] = decorations[i++];
      decorations[decPos++] = decorations[i++];
    } else {
      i += 2;
    }
  }
  nDecorations = decPos;

  // Simplify decorations.
  for (i = decPos = 0; i < nDecorations;) {
    var startPos = decorations[i];
    // Conflate all adjacent decorations that use the same style.
    var startDec = decorations[i + 1];
    var end = i + 2;
    while (end + 2 <= nDecorations && decorations[end + 1] === startDec) {
      end += 2;
    }
    decorations[decPos++] = startPos;
    decorations[decPos++] = startDec;
    i = end;
  }

  nDecorations = decorations.length = decPos;

  var decoration = null;
  while (spanIndex < nSpans) {
    var spanStart = spans[spanIndex];
    var spanEnd = spans[spanIndex + 2] || sourceLength;

    var decStart = decorations[decorationIndex];
    var decEnd = decorations[decorationIndex + 2] || sourceLength;

    var end = Math.min(spanEnd, decEnd);

    var textNode = spans[spanIndex + 1];
    var styledText;
    if (textNode.nodeType !== 1  // Don't muck with <BR>s or <LI>s
        // Don't introduce spans around empty text nodes.
        && (styledText = source.substring(sourceIndex, end))) {
      // This may seem bizarre, and it is.  Emitting LF on IE causes the
      // code to display with spaces instead of line breaks.
      // Emitting Windows standard issue linebreaks (CRLF) causes a blank
      // space to appear at the beginning of every line but the first.
      // Emitting an old Mac OS 9 line separator makes everything spiffy.
      if (isIE) { styledText = styledText.replace(newlineRe, '\r'); }
      textNode.nodeValue = styledText;
      var document = textNode.ownerDocument;
      var span = document.createElement('SPAN');
      span.className = decorations[decorationIndex + 1];
      var parentNode = textNode.parentNode;
      parentNode.replaceChild(span, textNode);
      span.appendChild(textNode);
      if (sourceIndex < spanEnd) {  // Split off a text node.
        spans[spanIndex + 1] = textNode
            // TODO: Possibly optimize by using '' if there's no flicker.
            = document.createTextNode(source.substring(end, spanEnd));
        parentNode.insertBefore(textNode, span.nextSibling);
      }
    }

    sourceIndex = end;

    if (sourceIndex >= spanEnd) {
      spanIndex += 2;
    }
    if (sourceIndex >= decEnd) {
      decorationIndex += 2;
    }
  }
}

/** Maps language-specific file extensions to handlers. */
var langHandlerRegistry = {};
/** Register a language handler for the given file extensions.
  * @param {function (Object)} handler a function from source code to a list
  *      of decorations.  Takes a single argument job which describes the
  *      state of the computation.   The single parameter has the form
  *      {@code {
  *        sourceCode: {string} as plain text.
  *        decorations: {Array.<number|string>} an array of style classes
  *                     preceded by the position at which they start in
  *                     job.sourceCode in order.
  *                     The language handler should assigned this field.
  *        basePos: {int} the position of source in the larger source chunk.
  *                 All positions in the output decorations array are relative
  *                 to the larger source chunk.
  *      } }
  * @param {Array.<string>} fileExtensions
  */
function registerLangHandler(handler, fileExtensions) {
  for (var i = fileExtensions.length; --i >= 0;) {
    var ext = fileExtensions[i];
    if (!langHandlerRegistry.hasOwnProperty(ext)) {
      langHandlerRegistry[ext] = handler;
    } else if (window['console']) {
      console['warn']('cannot override language handler %s', ext);
    }
  }
}
function langHandlerForExtension(extension, source) {
  if (!(extension && langHandlerRegistry.hasOwnProperty(extension))) {
    // Treat it as markup if the first non whitespace character is a < and
    // the last non-whitespace character is a >.
    extension = /^\s*</.test(source)
        ? 'default-markup'
        : 'default-code';
  }
  return langHandlerRegistry[extension];
}
registerLangHandler(decorateSource, ['default-code']);
registerLangHandler(
    createSimpleLexer(
        [],
        [
         [PR_PLAIN,       /^[^<?]+/],
         [PR_DECLARATION, /^<!\w[^>]*(?:>|$)/],
         [PR_COMMENT,     /^<\!--[\s\S]*?(?:-\->|$)/],
         // Unescaped content in an unknown language
         ['lang-',        /^<\?([\s\S]+?)(?:\?>|$)/],
         ['lang-',        /^<%([\s\S]+?)(?:%>|$)/],
         [PR_PUNCTUATION, /^(?:<[%?]|[%?]>)/],
         ['lang-',        /^<xmp\b[^>]*>([\s\S]+?)<\/xmp\b[^>]*>/i],
         // Unescaped content in javascript.  (Or possibly vbscript).
         ['lang-js',      /^<script\b[^>]*>([\s\S]*?)(<\/script\b[^>]*>)/i],
         // Contains unescaped stylesheet content
         ['lang-css',     /^<style\b[^>]*>([\s\S]*?)(<\/style\b[^>]*>)/i],
         ['lang-in.tag',  /^(<\/?[a-z][^<>]*>)/i]
        ]),
    ['default-markup', 'htm', 'html', 'mxml', 'xhtml', 'xml', 'xsl']);
registerLangHandler(
    createSimpleLexer(
        [
         [PR_PLAIN,        /^[\s]+/, null, ' \t\r\n'],
         [PR_ATTRIB_VALUE, /^(?:\"[^\"]*\"?|\'[^\']*\'?)/, null, '\"\'']
         ],
        [
         [PR_TAG,          /^^<\/?[a-z](?:[\w.:-]*\w)?|\/?>$/i],
         [PR_ATTRIB_NAME,  /^(?!style[\s=]|on)[a-z](?:[\w:-]*\w)?/i],
         ['lang-uq.val',   /^=\s*([^>\'\"\s]*(?:[^>\'\"\s\/]|\/(?=\s)))/],
         [PR_PUNCTUATION,  /^[=<>\/]+/],
         ['lang-js',       /^on\w+\s*=\s*\"([^\"]+)\"/i],
         ['lang-js',       /^on\w+\s*=\s*\'([^\']+)\'/i],
         ['lang-js',       /^on\w+\s*=\s*([^\"\'>\s]+)/i],
         ['lang-css',      /^style\s*=\s*\"([^\"]+)\"/i],
         ['lang-css',      /^style\s*=\s*\'([^\']+)\'/i],
         ['lang-css',      /^style\s*=\s*([^\"\'>\s]+)/i]
         ]),
    ['in.tag']);
registerLangHandler(
    createSimpleLexer([], [[PR_ATTRIB_VALUE, /^[\s\S]+/]]), ['uq.val']);
registerLangHandler(sourceDecorator({
        'keywords': CPP_KEYWORDS,
        'hashComments': true,
        'cStyleComments': true,
        'types': C_TYPES
      }), ['c', 'cc', 'cpp', 'cxx', 'cyc', 'm']);
registerLangHandler(sourceDecorator({
        'keywords': 'null,true,false'
      }), ['json']);
registerLangHandler(sourceDecorator({
        'keywords': CSHARP_KEYWORDS,
        'hashComments': true,
        'cStyleComments': true,
        'verbatimStrings': true,
        'types': C_TYPES
      }), ['cs']);
registerLangHandler(sourceDecorator({
        'keywords': JAVA_KEYWORDS,
        'cStyleComments': true
      }), ['java']);
registerLangHandler(sourceDecorator({
        'keywords': SH_KEYWORDS,
        'hashComments': true,
        'multiLineStrings': true
      }), ['bsh', 'csh', 'sh']);
registerLangHandler(sourceDecorator({
        'keywords': PYTHON_KEYWORDS,
        'hashComments': true,
        'multiLineStrings': true,
        'tripleQuotedStrings': true
      }), ['cv', 'py']);
registerLangHandler(sourceDecorator({
        'keywords': PERL_KEYWORDS,
        'hashComments': true,
        'multiLineStrings': true,
        'regexLiterals': true
      }), ['perl', 'pl', 'pm']);
registerLangHandler(sourceDecorator({
        'keywords': RUBY_KEYWORDS,
        'hashComments': true,
        'multiLineStrings': true,
        'regexLiterals': true
      }), ['rb']);
registerLangHandler(sourceDecorator({
        'keywords': JSCRIPT_KEYWORDS,
        'cStyleComments': true,
        'regexLiterals': true
      }), ['js']);
registerLangHandler(sourceDecorator({
        'keywords': COFFEE_KEYWORDS,
        'hashComments': 3,  // ### style block comments
        'cStyleComments': true,
        'multilineStrings': true,
        'tripleQuotedStrings': true,
        'regexLiterals': true
      }), ['coffee']);
registerLangHandler(createSimpleLexer([], [[PR_STRING, /^[\s\S]+/]]), ['regex']);

function applyDecorator(job) {
  var opt_langExtension = job.langExtension;

  try {
    // Extract tags, and convert the source code to plain text.
    var sourceAndSpans = extractSourceSpans(job.sourceNode);
    /** Plain text. @type {string} */
    var source = sourceAndSpans.sourceCode;
    job.sourceCode = source;
    job.spans = sourceAndSpans.spans;
    job.basePos = 0;

    // Apply the appropriate language handler
    langHandlerForExtension(opt_langExtension, source)(job);

    // Integrate the decorations and tags back into the source code,
    // modifying the sourceNode in place.
    recombineTagsAndDecorations(job);
  } catch (e) {
    if ('console' in window) {
      console['log'](e && e['stack'] ? e['stack'] : e);
    }
  }
}

/**
 * @param sourceCodeHtml {string} The HTML to pretty print.
 * @param opt_langExtension {string} The language name to use.
 *     Typically, a filename extension like 'cpp' or 'java'.
 * @param opt_numberLines {number|boolean} True to number lines,
 *     or the 1-indexed number of the first line in sourceCodeHtml.
 */
function prettyPrintOne(sourceCodeHtml, opt_langExtension, opt_numberLines) {
  var container = document.createElement('PRE');
  // This could cause images to load and onload listeners to fire.
  // E.g. <img onerror="alert(1337)" src="nosuchimage.png">.
  // We assume that the inner HTML is from a trusted source.
  container.innerHTML = sourceCodeHtml;
  if (opt_numberLines) {
    numberLines(container, opt_numberLines);
  }

  var job = {
    langExtension: opt_langExtension,
    numberLines: opt_numberLines,
    sourceNode: container
  };
  applyDecorator(job);
  return container.innerHTML;
}

function prettyPrint(opt_whenDone) {
  function byTagName(tn) { return document.getElementsByTagName(tn); }
  // fetch a list of nodes to rewrite
  var codeSegments = [byTagName('pre'), byTagName('code'), byTagName('xmp')];
  var elements = [];
  for (var i = 0; i < codeSegments.length; ++i) {
    for (var j = 0, n = codeSegments[i].length; j < n; ++j) {
      elements.push(codeSegments[i][j]);
    }
  }
  codeSegments = null;

  var clock = Date;
  if (!clock['now']) {
    clock = { 'now': function () { return +(new Date); } };
  }

  // The loop is broken into a series of continuations to make sure that we
  // don't make the browser unresponsive when rewriting a large page.
  var k = 0;
  var prettyPrintingJob;

  var langExtensionRe = /\blang(?:uage)?-([\w.]+)(?!\S)/;
  var prettyPrintRe = /\bprettyprint\b/;

  function doWork() {
    var endTime = (window['PR_SHOULD_USE_CONTINUATION'] ?
                   clock['now']() + 250 /* ms */ :
                   Infinity);
    for (; k < elements.length && clock['now']() < endTime; k++) {
      var cs = elements[k];
      var className = cs.className;
      if (className.indexOf('prettyprint') >= 0) {
        // If the classes includes a language extensions, use it.
        // Language extensions can be specified like
        //     <pre class="prettyprint lang-cpp">
        // the language extension "cpp" is used to find a language handler as
        // passed to PR.registerLangHandler.
        // HTML5 recommends that a language be specified using "language-"
        // as the prefix instead.  Google Code Prettify supports both.
        // http://dev.w3.org/html5/spec-author-view/the-code-element.html
        var langExtension = className.match(langExtensionRe);
        // Support <pre class="prettyprint"><code class="language-c">
        var wrapper;
        if (!langExtension && (wrapper = childContentWrapper(cs))
            && "CODE" === wrapper.tagName) {
          langExtension = wrapper.className.match(langExtensionRe);
        }

        if (langExtension) {
          langExtension = langExtension[1];
        }

        // make sure this is not nested in an already prettified element
        var nested = false;
        for (var p = cs.parentNode; p; p = p.parentNode) {
          if ((p.tagName === 'pre' || p.tagName === 'code' ||
               p.tagName === 'xmp') &&
              p.className && p.className.indexOf('prettyprint') >= 0) {
            nested = true;
            break;
          }
        }
        if (!nested) {
          // Look for a class like linenums or linenums:<n> where <n> is the
          // 1-indexed number of the first line.
          var lineNums = cs.className.match(/\blinenums\b(?::(\d+))?/);
          lineNums = lineNums
                ? lineNums[1] && lineNums[1].length ? +lineNums[1] : true
                : false;
          if (lineNums) { numberLines(cs, lineNums); }

          // do the pretty printing
          prettyPrintingJob = {
            langExtension: langExtension,
            sourceNode: cs,
            numberLines: lineNums
          };
          applyDecorator(prettyPrintingJob);
        }
      }
    }
    if (k < elements.length) {
      // finish up in a continuation
      setTimeout(doWork, 250);
    } else if (opt_whenDone) {
      opt_whenDone();
    }
  }

  doWork();
}

 /**
  * Find all the {@code <pre>} and {@code <code>} tags in the DOM with
  * {@code class=prettyprint} and prettify them.
  *
  * @param {Function?} opt_whenDone if specified, called when the last entry
  *     has been finished.
  */
window['prettyPrintOne'] = prettyPrintOne;
 /**
  * Pretty print a chunk of code.
  *
  * @param {string} sourceCodeHtml code as html
  * @return {string} code as html, but prettier
  */
window['prettyPrint'] = prettyPrint;
 /**
  * Contains functions for creating and registering new language handlers.
  * @type {Object}
  */
window['PR'] = {
      'createSimpleLexer': createSimpleLexer,
      'registerLangHandler': registerLangHandler,
      'sourceDecorator': sourceDecorator,
      'PR_ATTRIB_NAME': PR_ATTRIB_NAME,
      'PR_ATTRIB_VALUE': PR_ATTRIB_VALUE,
      'PR_COMMENT': PR_COMMENT,
      'PR_DECLARATION': PR_DECLARATION,
      'PR_KEYWORD': PR_KEYWORD,
      'PR_LITERAL': PR_LITERAL,
      'PR_NOCODE': PR_NOCODE,
      'PR_PLAIN': PR_PLAIN,
      'PR_PUNCTUATION': PR_PUNCTUATION,
      'PR_SOURCE': PR_SOURCE,
      'PR_STRING': PR_STRING,
      'PR_TAG': PR_TAG,
      'PR_TYPE': PR_TYPE
    };

})();