lca20-bt/lib/js/showdown.js
2012-07-31 01:13:33 -04:00

1341 lines
34 KiB
JavaScript

//
// showdown.js -- A javascript port of Markdown.
//
// Copyright (c) 2007 John Fraser.
//
// Original Markdown Copyright (c) 2004-2005 John Gruber
// <http://daringfireball.net/projects/markdown/>
//
// Redistributable under a BSD-style open source license.
// See license.txt for more information.
//
// The full source distribution is at:
//
// A A L
// T C A
// T K B
//
// <http://www.attacklab.net/>
//
//
// Wherever possible, Showdown is a straight, line-by-line port
// of the Perl version of Markdown.
//
// This is not a normal parser design; it's basically just a
// series of string substitutions. It's hard to read and
// maintain this way, but keeping Showdown close to the original
// design makes it easier to port new features.
//
// More importantly, Showdown behaves like markdown.pl in most
// edge cases. So web applications can do client-side preview
// in Javascript, and then build identical HTML on the server.
//
// This port needs the new RegExp functionality of ECMA 262,
// 3rd Edition (i.e. Javascript 1.5). Most modern web browsers
// should do fine. Even with the new regular expression features,
// We do a lot of work to emulate Perl's regex functionality.
// The tricky changes in this file mostly have the "attacklab:"
// label. Major or self-explanatory changes don't.
//
// Smart diff tools like Araxis Merge will be able to match up
// this file with markdown.pl in a useful way. A little tweaking
// helps: in a copy of markdown.pl, replace "#" with "//" and
// replace "$text" with "text". Be sure to ignore whitespace
// and line endings.
//
//
// Showdown usage:
//
// var text = "Markdown *rocks*.";
//
// var converter = new Showdown.converter();
// var html = converter.makeHtml(text);
//
// alert(html);
//
// Note: move the sample code to the bottom of this
// file before uncommenting it.
//
//
// Showdown namespace
//
var Showdown = {};
//
// converter
//
// Wraps all "globals" so that the only thing
// exposed is makeHtml().
//
Showdown.converter = function() {
//
// Globals:
//
// Global hashes, used by various utility routines
var g_urls;
var g_titles;
var g_html_blocks;
// Used to track when we're inside an ordered or unordered list
// (see _ProcessListItems() for details):
var g_list_level = 0;
this.makeHtml = function(text) {
//
// Main function. The order in which other subs are called here is
// essential. Link and image substitutions need to happen before
// _EscapeSpecialCharsWithinTagAttributes(), so that any *'s or _'s in the <a>
// and <img> tags get encoded.
//
// Clear the global hashes. If we don't clear these, you get conflicts
// from other articles when generating a page which contains more than
// one article (e.g. an index page that shows the N most recent
// articles):
g_urls = new Array();
g_titles = new Array();
g_html_blocks = new Array();
// attacklab: Replace ~ with ~T
// This lets us use tilde as an escape char to avoid md5 hashes
// The choice of character is arbitray; anything that isn't
// magic in Markdown will work.
text = text.replace(/~/g,"~T");
// attacklab: Replace $ with ~D
// RegExp interprets $ as a special character
// when it's in a replacement string
text = text.replace(/\$/g,"~D");
// Standardize line endings
text = text.replace(/\r\n/g,"\n"); // DOS to Unix
text = text.replace(/\r/g,"\n"); // Mac to Unix
// Make sure text begins and ends with a couple of newlines:
text = "\n\n" + text + "\n\n";
// Convert all tabs to spaces.
text = _Detab(text);
// Strip any lines consisting only of spaces and tabs.
// This makes subsequent regexen easier to write, because we can
// match consecutive blank lines with /\n+/ instead of something
// contorted like /[ \t]*\n+/ .
text = text.replace(/^[ \t]+$/mg,"");
// Handle github codeblocks prior to running HashHTML so that
// HTML contained within the codeblock gets escaped propertly
text = _DoGithubCodeBlocks(text);
// Turn block-level HTML blocks into hash entries
text = _HashHTMLBlocks(text);
// Strip link definitions, store in hashes.
text = _StripLinkDefinitions(text);
text = _RunBlockGamut(text);
text = _UnescapeSpecialChars(text);
// attacklab: Restore dollar signs
text = text.replace(/~D/g,"$$");
// attacklab: Restore tildes
text = text.replace(/~T/g,"~");
return text;
};
var _StripLinkDefinitions = function(text) {
//
// Strips link definitions from text, stores the URLs and titles in
// hash references.
//
// Link defs are in the form: ^[id]: url "optional title"
/*
var text = text.replace(/
^[ ]{0,3}\[(.+)\]: // id = $1 attacklab: g_tab_width - 1
[ \t]*
\n? // maybe *one* newline
[ \t]*
<?(\S+?)>? // url = $2
[ \t]*
\n? // maybe one newline
[ \t]*
(?:
(\n*) // any lines skipped = $3 attacklab: lookbehind removed
["(]
(.+?) // title = $4
[")]
[ \t]*
)? // title is optional
(?:\n+|$)
/gm,
function(){...});
*/
var text = text.replace(/^[ ]{0,3}\[(.+)\]:[ \t]*\n?[ \t]*<?(\S+?)>?[ \t]*\n?[ \t]*(?:(\n*)["(](.+?)[")][ \t]*)?(?:\n+|\Z)/gm,
function (wholeMatch,m1,m2,m3,m4) {
m1 = m1.toLowerCase();
g_urls[m1] = _EncodeAmpsAndAngles(m2); // Link IDs are case-insensitive
if (m3) {
// Oops, found blank lines, so it's not a title.
// Put back the parenthetical statement we stole.
return m3+m4;
} else if (m4) {
g_titles[m1] = m4.replace(/"/g,"&quot;");
}
// Completely remove the definition from the text
return "";
}
);
return text;
}
var _HashHTMLBlocks = function(text) {
// attacklab: Double up blank lines to reduce lookaround
text = text.replace(/\n/g,"\n\n");
// Hashify HTML blocks:
// We only want to do this for block-level HTML tags, such as headers,
// lists, and tables. That's because we still want to wrap <p>s around
// "paragraphs" that are wrapped in non-block-level tags, such as anchors,
// phrase emphasis, and spans. The list of tags we're looking for is
// hard-coded:
var block_tags_a = "p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del|style|section|header|footer|nav|article|aside";
var block_tags_b = "p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|style|section|header|footer|nav|article|aside";
// First, look for nested blocks, e.g.:
// <div>
// <div>
// tags for inner block must be indented.
// </div>
// </div>
//
// The outermost tags must start at the left margin for this to match, and
// the inner nested divs must be indented.
// We need to do this before the next, more liberal match, because the next
// match will start at the first `<div>` and stop at the first `</div>`.
// attacklab: This regex can be expensive when it fails.
/*
var text = text.replace(/
( // save in $1
^ // start of line (with /m)
<($block_tags_a) // start tag = $2
\b // word break
// attacklab: hack around khtml/pcre bug...
[^\r]*?\n // any number of lines, minimally matching
</\2> // the matching end tag
[ \t]* // trailing spaces/tabs
(?=\n+) // followed by a newline
) // attacklab: there are sentinel newlines at end of document
/gm,function(){...}};
*/
text = text.replace(/^(<(p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|ins|del)\b[^\r]*?\n<\/\2>[ \t]*(?=\n+))/gm,hashElement);
//
// Now match more liberally, simply from `\n<tag>` to `</tag>\n`
//
/*
var text = text.replace(/
( // save in $1
^ // start of line (with /m)
<($block_tags_b) // start tag = $2
\b // word break
// attacklab: hack around khtml/pcre bug...
[^\r]*? // any number of lines, minimally matching
.*</\2> // the matching end tag
[ \t]* // trailing spaces/tabs
(?=\n+) // followed by a newline
) // attacklab: there are sentinel newlines at end of document
/gm,function(){...}};
*/
text = text.replace(/^(<(p|div|h[1-6]|blockquote|pre|table|dl|ol|ul|script|noscript|form|fieldset|iframe|math|style|section|header|footer|nav|article|aside)\b[^\r]*?.*<\/\2>[ \t]*(?=\n+)\n)/gm,hashElement);
// Special case just for <hr />. It was easier to make a special case than
// to make the other regex more complicated.
/*
text = text.replace(/
( // save in $1
\n\n // Starting after a blank line
[ ]{0,3}
(<(hr) // start tag = $2
\b // word break
([^<>])*? //
\/?>) // the matching end tag
[ \t]*
(?=\n{2,}) // followed by a blank line
)
/g,hashElement);
*/
text = text.replace(/(\n[ ]{0,3}(<(hr)\b([^<>])*?\/?>)[ \t]*(?=\n{2,}))/g,hashElement);
// Special case for standalone HTML comments:
/*
text = text.replace(/
( // save in $1
\n\n // Starting after a blank line
[ ]{0,3} // attacklab: g_tab_width - 1
<!
(--[^\r]*?--\s*)+
>
[ \t]*
(?=\n{2,}) // followed by a blank line
)
/g,hashElement);
*/
text = text.replace(/(\n\n[ ]{0,3}<!(--[^\r]*?--\s*)+>[ \t]*(?=\n{2,}))/g,hashElement);
// PHP and ASP-style processor instructions (<?...?> and <%...%>)
/*
text = text.replace(/
(?:
\n\n // Starting after a blank line
)
( // save in $1
[ ]{0,3} // attacklab: g_tab_width - 1
(?:
<([?%]) // $2
[^\r]*?
\2>
)
[ \t]*
(?=\n{2,}) // followed by a blank line
)
/g,hashElement);
*/
text = text.replace(/(?:\n\n)([ ]{0,3}(?:<([?%])[^\r]*?\2>)[ \t]*(?=\n{2,}))/g,hashElement);
// attacklab: Undo double lines (see comment at top of this function)
text = text.replace(/\n\n/g,"\n");
return text;
}
var hashElement = function(wholeMatch,m1) {
var blockText = m1;
// Undo double lines
blockText = blockText.replace(/\n\n/g,"\n");
blockText = blockText.replace(/^\n/,"");
// strip trailing blank lines
blockText = blockText.replace(/\n+$/g,"");
// Replace the element text with a marker ("~KxK" where x is its key)
blockText = "\n\n~K" + (g_html_blocks.push(blockText)-1) + "K\n\n";
return blockText;
};
var _RunBlockGamut = function(text) {
//
// These are all the transformations that form block-level
// tags like paragraphs, headers, and list items.
//
text = _DoHeaders(text);
// Do Horizontal Rules:
var key = hashBlock("<hr />");
text = text.replace(/^[ ]{0,2}([ ]?\*[ ]?){3,}[ \t]*$/gm,key);
text = text.replace(/^[ ]{0,2}([ ]?\-[ ]?){3,}[ \t]*$/gm,key);
text = text.replace(/^[ ]{0,2}([ ]?\_[ ]?){3,}[ \t]*$/gm,key);
text = _DoLists(text);
text = _DoCodeBlocks(text);
text = _DoBlockQuotes(text);
// We already ran _HashHTMLBlocks() before, in Markdown(), but that
// was to escape raw HTML in the original Markdown source. This time,
// we're escaping the markup we've just created, so that we don't wrap
// <p> tags around block-level tags.
text = _HashHTMLBlocks(text);
text = _FormParagraphs(text);
return text;
};
var _RunSpanGamut = function(text) {
//
// These are all the transformations that occur *within* block-level
// tags like paragraphs, headers, and list items.
//
text = _DoCodeSpans(text);
text = _EscapeSpecialCharsWithinTagAttributes(text);
text = _EncodeBackslashEscapes(text);
// Process anchor and image tags. Images must come first,
// because ![foo][f] looks like an anchor.
text = _DoImages(text);
text = _DoAnchors(text);
// Make links out of things like `<http://example.com/>`
// Must come after _DoAnchors(), because you can use < and >
// delimiters in inline links like [this](<url>).
text = _DoAutoLinks(text);
text = _EncodeAmpsAndAngles(text);
text = _DoItalicsAndBold(text);
// Do hard breaks:
text = text.replace(/ +\n/g," <br />\n");
return text;
}
var _EscapeSpecialCharsWithinTagAttributes = function(text) {
//
// Within tags -- meaning between < and > -- encode [\ ` * _] so they
// don't conflict with their use in Markdown for code, italics and strong.
//
// Build a regex to find HTML tags and comments. See Friedl's
// "Mastering Regular Expressions", 2nd Ed., pp. 200-201.
var regex = /(<[a-z\/!$]("[^"]*"|'[^']*'|[^'">])*>|<!(--.*?--\s*)+>)/gi;
text = text.replace(regex, function(wholeMatch) {
var tag = wholeMatch.replace(/(.)<\/?code>(?=.)/g,"$1`");
tag = escapeCharacters(tag,"\\`*_");
return tag;
});
return text;
}
var _DoAnchors = function(text) {
//
// Turn Markdown link shortcuts into XHTML <a> tags.
//
//
// First, handle reference-style links: [link text] [id]
//
/*
text = text.replace(/
( // wrap whole match in $1
\[
(
(?:
\[[^\]]*\] // allow brackets nested one level
|
[^\[] // or anything else
)*
)
\]
[ ]? // one optional space
(?:\n[ ]*)? // one optional newline followed by spaces
\[
(.*?) // id = $3
\]
)()()()() // pad remaining backreferences
/g,_DoAnchors_callback);
*/
text = text.replace(/(\[((?:\[[^\]]*\]|[^\[\]])*)\][ ]?(?:\n[ ]*)?\[(.*?)\])()()()()/g,writeAnchorTag);
//
// Next, inline-style links: [link text](url "optional title")
//
/*
text = text.replace(/
( // wrap whole match in $1
\[
(
(?:
\[[^\]]*\] // allow brackets nested one level
|
[^\[\]] // or anything else
)
)
\]
\( // literal paren
[ \t]*
() // no id, so leave $3 empty
<?(.*?)>? // href = $4
[ \t]*
( // $5
(['"]) // quote char = $6
(.*?) // Title = $7
\6 // matching quote
[ \t]* // ignore any spaces/tabs between closing quote and )
)? // title is optional
\)
)
/g,writeAnchorTag);
*/
text = text.replace(/(\[((?:\[[^\]]*\]|[^\[\]])*)\]\([ \t]*()<?(.*?)>?[ \t]*((['"])(.*?)\6[ \t]*)?\))/g,writeAnchorTag);
//
// Last, handle reference-style shortcuts: [link text]
// These must come last in case you've also got [link test][1]
// or [link test](/foo)
//
/*
text = text.replace(/
( // wrap whole match in $1
\[
([^\[\]]+) // link text = $2; can't contain '[' or ']'
\]
)()()()()() // pad rest of backreferences
/g, writeAnchorTag);
*/
text = text.replace(/(\[([^\[\]]+)\])()()()()()/g, writeAnchorTag);
return text;
}
var writeAnchorTag = function(wholeMatch,m1,m2,m3,m4,m5,m6,m7) {
if (m7 == undefined) m7 = "";
var whole_match = m1;
var link_text = m2;
var link_id = m3.toLowerCase();
var url = m4;
var title = m7;
if (url == "") {
if (link_id == "") {
// lower-case and turn embedded newlines into spaces
link_id = link_text.toLowerCase().replace(/ ?\n/g," ");
}
url = "#"+link_id;
if (g_urls[link_id] != undefined) {
url = g_urls[link_id];
if (g_titles[link_id] != undefined) {
title = g_titles[link_id];
}
}
else {
if (whole_match.search(/\(\s*\)$/m)>-1) {
// Special case for explicit empty url
url = "";
} else {
return whole_match;
}
}
}
url = escapeCharacters(url,"*_");
var result = "<a href=\"" + url + "\"";
if (title != "") {
title = title.replace(/"/g,"&quot;");
title = escapeCharacters(title,"*_");
result += " title=\"" + title + "\"";
}
result += ">" + link_text + "</a>";
return result;
}
var _DoImages = function(text) {
//
// Turn Markdown image shortcuts into <img> tags.
//
//
// First, handle reference-style labeled images: ![alt text][id]
//
/*
text = text.replace(/
( // wrap whole match in $1
!\[
(.*?) // alt text = $2
\]
[ ]? // one optional space
(?:\n[ ]*)? // one optional newline followed by spaces
\[
(.*?) // id = $3
\]
)()()()() // pad rest of backreferences
/g,writeImageTag);
*/
text = text.replace(/(!\[(.*?)\][ ]?(?:\n[ ]*)?\[(.*?)\])()()()()/g,writeImageTag);
//
// Next, handle inline images: ![alt text](url "optional title")
// Don't forget: encode * and _
/*
text = text.replace(/
( // wrap whole match in $1
!\[
(.*?) // alt text = $2
\]
\s? // One optional whitespace character
\( // literal paren
[ \t]*
() // no id, so leave $3 empty
<?(\S+?)>? // src url = $4
[ \t]*
( // $5
(['"]) // quote char = $6
(.*?) // title = $7
\6 // matching quote
[ \t]*
)? // title is optional
\)
)
/g,writeImageTag);
*/
text = text.replace(/(!\[(.*?)\]\s?\([ \t]*()<?(\S+?)>?[ \t]*((['"])(.*?)\6[ \t]*)?\))/g,writeImageTag);
return text;
}
var writeImageTag = function(wholeMatch,m1,m2,m3,m4,m5,m6,m7) {
var whole_match = m1;
var alt_text = m2;
var link_id = m3.toLowerCase();
var url = m4;
var title = m7;
if (!title) title = "";
if (url == "") {
if (link_id == "") {
// lower-case and turn embedded newlines into spaces
link_id = alt_text.toLowerCase().replace(/ ?\n/g," ");
}
url = "#"+link_id;
if (g_urls[link_id] != undefined) {
url = g_urls[link_id];
if (g_titles[link_id] != undefined) {
title = g_titles[link_id];
}
}
else {
return whole_match;
}
}
alt_text = alt_text.replace(/"/g,"&quot;");
url = escapeCharacters(url,"*_");
var result = "<img src=\"" + url + "\" alt=\"" + alt_text + "\"";
// attacklab: Markdown.pl adds empty title attributes to images.
// Replicate this bug.
//if (title != "") {
title = title.replace(/"/g,"&quot;");
title = escapeCharacters(title,"*_");
result += " title=\"" + title + "\"";
//}
result += " />";
return result;
}
var _DoHeaders = function(text) {
// Setext-style headers:
// Header 1
// ========
//
// Header 2
// --------
//
text = text.replace(/^(.+)[ \t]*\n=+[ \t]*\n+/gm,
function(wholeMatch,m1){return hashBlock('<h1 id="' + headerId(m1) + '">' + _RunSpanGamut(m1) + "</h1>");});
text = text.replace(/^(.+)[ \t]*\n-+[ \t]*\n+/gm,
function(matchFound,m1){return hashBlock('<h2 id="' + headerId(m1) + '">' + _RunSpanGamut(m1) + "</h2>");});
// atx-style headers:
// # Header 1
// ## Header 2
// ## Header 2 with closing hashes ##
// ...
// ###### Header 6
//
/*
text = text.replace(/
^(\#{1,6}) // $1 = string of #'s
[ \t]*
(.+?) // $2 = Header text
[ \t]*
\#* // optional closing #'s (not counted)
\n+
/gm, function() {...});
*/
text = text.replace(/^(\#{1,6})[ \t]*(.+?)[ \t]*\#*\n+/gm,
function(wholeMatch,m1,m2) {
var h_level = m1.length;
return hashBlock("<h" + h_level + ' id="' + headerId(m2) + '">' + _RunSpanGamut(m2) + "</h" + h_level + ">");
});
function headerId(m) {
return m.replace(/[^\w]/g, '').toLowerCase();
}
return text;
}
// This declaration keeps Dojo compressor from outputting garbage:
var _ProcessListItems;
var _DoLists = function(text) {
//
// Form HTML ordered (numbered) and unordered (bulleted) lists.
//
// attacklab: add sentinel to hack around khtml/safari bug:
// http://bugs.webkit.org/show_bug.cgi?id=11231
text += "~0";
// Re-usable pattern to match any entirel ul or ol list:
/*
var whole_list = /
( // $1 = whole list
( // $2
[ ]{0,3} // attacklab: g_tab_width - 1
([*+-]|\d+[.]) // $3 = first list item marker
[ \t]+
)
[^\r]+?
( // $4
~0 // sentinel for workaround; should be $
|
\n{2,}
(?=\S)
(?! // Negative lookahead for another list item marker
[ \t]*
(?:[*+-]|\d+[.])[ \t]+
)
)
)/g
*/
var whole_list = /^(([ ]{0,3}([*+-]|\d+[.])[ \t]+)[^\r]+?(~0|\n{2,}(?=\S)(?![ \t]*(?:[*+-]|\d+[.])[ \t]+)))/gm;
if (g_list_level) {
text = text.replace(whole_list,function(wholeMatch,m1,m2) {
var list = m1;
var list_type = (m2.search(/[*+-]/g)>-1) ? "ul" : "ol";
// Turn double returns into triple returns, so that we can make a
// paragraph for the last item in a list, if necessary:
list = list.replace(/\n{2,}/g,"\n\n\n");;
var result = _ProcessListItems(list);
// Trim any trailing whitespace, to put the closing `</$list_type>`
// up on the preceding line, to get it past the current stupid
// HTML block parser. This is a hack to work around the terrible
// hack that is the HTML block parser.
result = result.replace(/\s+$/,"");
result = "<"+list_type+">" + result + "</"+list_type+">\n";
return result;
});
} else {
whole_list = /(\n\n|^\n?)(([ ]{0,3}([*+-]|\d+[.])[ \t]+)[^\r]+?(~0|\n{2,}(?=\S)(?![ \t]*(?:[*+-]|\d+[.])[ \t]+)))/g;
text = text.replace(whole_list,function(wholeMatch,m1,m2,m3) {
var runup = m1;
var list = m2;
var list_type = (m3.search(/[*+-]/g)>-1) ? "ul" : "ol";
// Turn double returns into triple returns, so that we can make a
// paragraph for the last item in a list, if necessary:
var list = list.replace(/\n{2,}/g,"\n\n\n");;
var result = _ProcessListItems(list);
result = runup + "<"+list_type+">\n" + result + "</"+list_type+">\n";
return result;
});
}
// attacklab: strip sentinel
text = text.replace(/~0/,"");
return text;
}
_ProcessListItems = function(list_str) {
//
// Process the contents of a single ordered or unordered list, splitting it
// into individual list items.
//
// The $g_list_level global keeps track of when we're inside a list.
// Each time we enter a list, we increment it; when we leave a list,
// we decrement. If it's zero, we're not in a list anymore.
//
// We do this because when we're not inside a list, we want to treat
// something like this:
//
// I recommend upgrading to version
// 8. Oops, now this line is treated
// as a sub-list.
//
// As a single paragraph, despite the fact that the second line starts
// with a digit-period-space sequence.
//
// Whereas when we're inside a list (or sub-list), that line will be
// treated as the start of a sub-list. What a kludge, huh? This is
// an aspect of Markdown's syntax that's hard to parse perfectly
// without resorting to mind-reading. Perhaps the solution is to
// change the syntax rules such that sub-lists must start with a
// starting cardinal number; e.g. "1." or "a.".
g_list_level++;
// trim trailing blank lines:
list_str = list_str.replace(/\n{2,}$/,"\n");
// attacklab: add sentinel to emulate \z
list_str += "~0";
/*
list_str = list_str.replace(/
(\n)? // leading line = $1
(^[ \t]*) // leading whitespace = $2
([*+-]|\d+[.]) [ \t]+ // list marker = $3
([^\r]+? // list item text = $4
(\n{1,2}))
(?= \n* (~0 | \2 ([*+-]|\d+[.]) [ \t]+))
/gm, function(){...});
*/
list_str = list_str.replace(/(\n)?(^[ \t]*)([*+-]|\d+[.])[ \t]+([^\r]+?(\n{1,2}))(?=\n*(~0|\2([*+-]|\d+[.])[ \t]+))/gm,
function(wholeMatch,m1,m2,m3,m4){
var item = m4;
var leading_line = m1;
var leading_space = m2;
if (leading_line || (item.search(/\n{2,}/)>-1)) {
item = _RunBlockGamut(_Outdent(item));
}
else {
// Recursion for sub-lists:
item = _DoLists(_Outdent(item));
item = item.replace(/\n$/,""); // chomp(item)
item = _RunSpanGamut(item);
}
return "<li>" + item + "</li>\n";
}
);
// attacklab: strip sentinel
list_str = list_str.replace(/~0/g,"");
g_list_level--;
return list_str;
}
var _DoCodeBlocks = function(text) {
//
// Process Markdown `<pre><code>` blocks.
//
/*
text = text.replace(text,
/(?:\n\n|^)
( // $1 = the code block -- one or more lines, starting with a space/tab
(?:
(?:[ ]{4}|\t) // Lines must start with a tab or a tab-width of spaces - attacklab: g_tab_width
.*\n+
)+
)
(\n*[ ]{0,3}[^ \t\n]|(?=~0)) // attacklab: g_tab_width
/g,function(){...});
*/
// attacklab: sentinel workarounds for lack of \A and \Z, safari\khtml bug
text += "~0";
text = text.replace(/(?:\n\n|^)((?:(?:[ ]{4}|\t).*\n+)+)(\n*[ ]{0,3}[^ \t\n]|(?=~0))/g,
function(wholeMatch,m1,m2) {
var codeblock = m1;
var nextChar = m2;
codeblock = _EncodeCode( _Outdent(codeblock));
codeblock = _Detab(codeblock);
codeblock = codeblock.replace(/^\n+/g,""); // trim leading newlines
codeblock = codeblock.replace(/\n+$/g,""); // trim trailing whitespace
codeblock = "<pre><code>" + codeblock + "\n</code></pre>";
return hashBlock(codeblock) + nextChar;
}
);
// attacklab: strip sentinel
text = text.replace(/~0/,"");
return text;
};
var _DoGithubCodeBlocks = function(text) {
//
// Process Github-style code blocks
// Example:
// ```ruby
// def hello_world(x)
// puts "Hello, #{x}"
// end
// ```
//
// attacklab: sentinel workarounds for lack of \A and \Z, safari\khtml bug
text += "~0";
text = text.replace(/(?:^|\n)```(.*)\n([\s\S]*?)\n```/g,
function(wholeMatch,m1,m2) {
var language = m1;
var codeblock = m2;
codeblock = _EncodeCode(codeblock);
codeblock = _Detab(codeblock);
codeblock = codeblock.replace(/^\n+/g,""); // trim leading newlines
codeblock = codeblock.replace(/\n+$/g,""); // trim trailing whitespace
codeblock = "<pre><code" + (language ? " class=\"" + language + '"' : "") + ">" + codeblock + "\n</code></pre>";
return hashBlock(codeblock);
}
);
// attacklab: strip sentinel
text = text.replace(/~0/,"");
return text;
}
var hashBlock = function(text) {
text = text.replace(/(^\n+|\n+$)/g,"");
return "\n\n~K" + (g_html_blocks.push(text)-1) + "K\n\n";
}
var _DoCodeSpans = function(text) {
//
// * Backtick quotes are used for <code></code> spans.
//
// * You can use multiple backticks as the delimiters if you want to
// include literal backticks in the code span. So, this input:
//
// Just type ``foo `bar` baz`` at the prompt.
//
// Will translate to:
//
// <p>Just type <code>foo `bar` baz</code> at the prompt.</p>
//
// There's no arbitrary limit to the number of backticks you
// can use as delimters. If you need three consecutive backticks
// in your code, use four for delimiters, etc.
//
// * You can use spaces to get literal backticks at the edges:
//
// ... type `` `bar` `` ...
//
// Turns to:
//
// ... type <code>`bar`</code> ...
//
/*
text = text.replace(/
(^|[^\\]) // Character before opening ` can't be a backslash
(`+) // $2 = Opening run of `
( // $3 = The code block
[^\r]*?
[^`] // attacklab: work around lack of lookbehind
)
\2 // Matching closer
(?!`)
/gm, function(){...});
*/
text = text.replace(/(^|[^\\])(`+)([^\r]*?[^`])\2(?!`)/gm,
function(wholeMatch,m1,m2,m3,m4) {
var c = m3;
c = c.replace(/^([ \t]*)/g,""); // leading whitespace
c = c.replace(/[ \t]*$/g,""); // trailing whitespace
c = _EncodeCode(c);
return m1+"<code>"+c+"</code>";
});
return text;
}
var _EncodeCode = function(text) {
//
// Encode/escape certain characters inside Markdown code runs.
// The point is that in code, these characters are literals,
// and lose their special Markdown meanings.
//
// Encode all ampersands; HTML entities are not
// entities within a Markdown code span.
text = text.replace(/&/g,"&amp;");
// Do the angle bracket song and dance:
text = text.replace(/</g,"&lt;");
text = text.replace(/>/g,"&gt;");
// Now, escape characters that are magic in Markdown:
text = escapeCharacters(text,"\*_{}[]\\",false);
// jj the line above breaks this:
//---
//* Item
// 1. Subitem
// special char: *
//---
return text;
}
var _DoItalicsAndBold = function(text) {
// <strong> must go first:
text = text.replace(/(\*\*|__)(?=\S)([^\r]*?\S[*_]*)\1/g,
"<strong>$2</strong>");
text = text.replace(/(\*|_)(?=\S)([^\r]*?\S)\1/g,
"<em>$2</em>");
return text;
}
var _DoBlockQuotes = function(text) {
/*
text = text.replace(/
( // Wrap whole match in $1
(
^[ \t]*>[ \t]? // '>' at the start of a line
.+\n // rest of the first line
(.+\n)* // subsequent consecutive lines
\n* // blanks
)+
)
/gm, function(){...});
*/
text = text.replace(/((^[ \t]*>[ \t]?.+\n(.+\n)*\n*)+)/gm,
function(wholeMatch,m1) {
var bq = m1;
// attacklab: hack around Konqueror 3.5.4 bug:
// "----------bug".replace(/^-/g,"") == "bug"
bq = bq.replace(/^[ \t]*>[ \t]?/gm,"~0"); // trim one level of quoting
// attacklab: clean up hack
bq = bq.replace(/~0/g,"");
bq = bq.replace(/^[ \t]+$/gm,""); // trim whitespace-only lines
bq = _RunBlockGamut(bq); // recurse
bq = bq.replace(/(^|\n)/g,"$1 ");
// These leading spaces screw with <pre> content, so we need to fix that:
bq = bq.replace(
/(\s*<pre>[^\r]+?<\/pre>)/gm,
function(wholeMatch,m1) {
var pre = m1;
// attacklab: hack around Konqueror 3.5.4 bug:
pre = pre.replace(/^ /mg,"~0");
pre = pre.replace(/~0/g,"");
return pre;
});
return hashBlock("<blockquote>\n" + bq + "\n</blockquote>");
});
return text;
}
var _FormParagraphs = function(text) {
//
// Params:
// $text - string to process with html <p> tags
//
// Strip leading and trailing lines:
text = text.replace(/^\n+/g,"");
text = text.replace(/\n+$/g,"");
var grafs = text.split(/\n{2,}/g);
var grafsOut = new Array();
//
// Wrap <p> tags.
//
var end = grafs.length;
for (var i=0; i<end; i++) {
var str = grafs[i];
// if this is an HTML marker, copy it
if (str.search(/~K(\d+)K/g) >= 0) {
grafsOut.push(str);
}
else if (str.search(/\S/) >= 0) {
str = _RunSpanGamut(str);
str = str.replace(/^([ \t]*)/g,"<p>");
str += "</p>"
grafsOut.push(str);
}
}
//
// Unhashify HTML blocks
//
end = grafsOut.length;
for (var i=0; i<end; i++) {
// if this is a marker for an html block...
while (grafsOut[i].search(/~K(\d+)K/) >= 0) {
var blockText = g_html_blocks[RegExp.$1];
blockText = blockText.replace(/\$/g,"$$$$"); // Escape any dollar signs
grafsOut[i] = grafsOut[i].replace(/~K\d+K/,blockText);
}
}
return grafsOut.join("\n\n");
}
var _EncodeAmpsAndAngles = function(text) {
// Smart processing for ampersands and angle brackets that need to be encoded.
// Ampersand-encoding based entirely on Nat Irons's Amputator MT plugin:
// http://bumppo.net/projects/amputator/
text = text.replace(/&(?!#?[xX]?(?:[0-9a-fA-F]+|\w+);)/g,"&amp;");
// Encode naked <'s
text = text.replace(/<(?![a-z\/?\$!])/gi,"&lt;");
return text;
}
var _EncodeBackslashEscapes = function(text) {
//
// Parameter: String.
// Returns: The string, with after processing the following backslash
// escape sequences.
//
// attacklab: The polite way to do this is with the new
// escapeCharacters() function:
//
// text = escapeCharacters(text,"\\",true);
// text = escapeCharacters(text,"`*_{}[]()>#+-.!",true);
//
// ...but we're sidestepping its use of the (slow) RegExp constructor
// as an optimization for Firefox. This function gets called a LOT.
text = text.replace(/\\(\\)/g,escapeCharacters_callback);
text = text.replace(/\\([`*_{}\[\]()>#+-.!])/g,escapeCharacters_callback);
return text;
}
var _DoAutoLinks = function(text) {
text = text.replace(/<((https?|ftp|dict):[^'">\s]+)>/gi,"<a href=\"$1\">$1</a>");
// Email addresses: <address@domain.foo>
/*
text = text.replace(/
<
(?:mailto:)?
(
[-.\w]+
\@
[-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+
)
>
/gi, _DoAutoLinks_callback());
*/
text = text.replace(/<(?:mailto:)?([-.\w]+\@[-a-z0-9]+(\.[-a-z0-9]+)*\.[a-z]+)>/gi,
function(wholeMatch,m1) {
return _EncodeEmailAddress( _UnescapeSpecialChars(m1) );
}
);
return text;
}
var _EncodeEmailAddress = function(addr) {
//
// Input: an email address, e.g. "foo@example.com"
//
// Output: the email address as a mailto link, with each character
// of the address encoded as either a decimal or hex entity, in
// the hopes of foiling most address harvesting spam bots. E.g.:
//
// <a href="&#x6D;&#97;&#105;&#108;&#x74;&#111;:&#102;&#111;&#111;&#64;&#101;
// x&#x61;&#109;&#x70;&#108;&#x65;&#x2E;&#99;&#111;&#109;">&#102;&#111;&#111;
// &#64;&#101;x&#x61;&#109;&#x70;&#108;&#x65;&#x2E;&#99;&#111;&#109;</a>
//
// Based on a filter by Matthew Wickline, posted to the BBEdit-Talk
// mailing list: <http://tinyurl.com/yu7ue>
//
// attacklab: why can't javascript speak hex?
function char2hex(ch) {
var hexDigits = '0123456789ABCDEF';
var dec = ch.charCodeAt(0);
return(hexDigits.charAt(dec>>4) + hexDigits.charAt(dec&15));
}
var encode = [
function(ch){return "&#"+ch.charCodeAt(0)+";";},
function(ch){return "&#x"+char2hex(ch)+";";},
function(ch){return ch;}
];
addr = "mailto:" + addr;
addr = addr.replace(/./g, function(ch) {
if (ch == "@") {
// this *must* be encoded. I insist.
ch = encode[Math.floor(Math.random()*2)](ch);
} else if (ch !=":") {
// leave ':' alone (to spot mailto: later)
var r = Math.random();
// roughly 10% raw, 45% hex, 45% dec
ch = (
r > .9 ? encode[2](ch) :
r > .45 ? encode[1](ch) :
encode[0](ch)
);
}
return ch;
});
addr = "<a href=\"" + addr + "\">" + addr + "</a>";
addr = addr.replace(/">.+:/g,"\">"); // strip the mailto: from the visible part
return addr;
}
var _UnescapeSpecialChars = function(text) {
//
// Swap back in all the special characters we've hidden.
//
text = text.replace(/~E(\d+)E/g,
function(wholeMatch,m1) {
var charCodeToReplace = parseInt(m1);
return String.fromCharCode(charCodeToReplace);
}
);
return text;
}
var _Outdent = function(text) {
//
// Remove one level of line-leading tabs or spaces
//
// attacklab: hack around Konqueror 3.5.4 bug:
// "----------bug".replace(/^-/g,"") == "bug"
text = text.replace(/^(\t|[ ]{1,4})/gm,"~0"); // attacklab: g_tab_width
// attacklab: clean up hack
text = text.replace(/~0/g,"")
return text;
}
var _Detab = function(text) {
// attacklab: Detab's completely rewritten for speed.
// In perl we could fix it by anchoring the regexp with \G.
// In javascript we're less fortunate.
// expand first n-1 tabs
text = text.replace(/\t(?=\t)/g," "); // attacklab: g_tab_width
// replace the nth with two sentinels
text = text.replace(/\t/g,"~A~B");
// use the sentinel to anchor our regex so it doesn't explode
text = text.replace(/~B(.+?)~A/g,
function(wholeMatch,m1,m2) {
var leadingText = m1;
var numSpaces = 4 - leadingText.length % 4; // attacklab: g_tab_width
// there *must* be a better way to do this:
for (var i=0; i<numSpaces; i++) leadingText+=" ";
return leadingText;
}
);
// clean up sentinels
text = text.replace(/~A/g," "); // attacklab: g_tab_width
text = text.replace(/~B/g,"");
return text;
}
//
// attacklab: Utility functions
//
var escapeCharacters = function(text, charsToEscape, afterBackslash) {
// First we have to escape the escape characters so that
// we can build a character class out of them
var regexString = "([" + charsToEscape.replace(/([\[\]\\])/g,"\\$1") + "])";
if (afterBackslash) {
regexString = "\\\\" + regexString;
}
var regex = new RegExp(regexString,"g");
text = text.replace(regex,escapeCharacters_callback);
return text;
}
var escapeCharacters_callback = function(wholeMatch,m1) {
var charCodeToEscape = m1.charCodeAt(0);
return "~E"+charCodeToEscape+"E";
}
} // end of Showdown.converter
// export
if (typeof module !== 'undefined') module.exports = Showdown;