showdown/src/subParsers/stripLinkDefinitions.js

A Markdown to HTML converter written in Javascript

/**
 * Strips link definitions from text, stores the URLs and titles in
 * hash references.
 * Link defs are in the form: ^[id]: url "optional title"
 */
showdown.subParser('stripLinkDefinitions', function (text, options, globals) {
  'use strict';

  var regex = /^ {0,3}\[(.+)]:[ \t]*\n?[ \t]*<?(\S+?)>?(?: =([*\d]+[A-Za-z%]{0,4})x([*\d]+[A-Za-z%]{0,4}))?[ \t]*\n?[ \t]*(?:(\n*)["|'(](.+?)["|')][ \t]*)?(?:\n+|(?=~0))/gm;

  // attacklab: sentinel workarounds for lack of \A and \Z, safari\khtml bug
  text += '~0';

  text = text.replace(regex, function (wholeMatch, linkId, url, width, height, blankLines, title) {
    linkId = linkId.toLowerCase();
    globals.gUrls[linkId] = showdown.subParser('encodeAmpsAndAngles')(url);  // Link IDs are case-insensitive

    if (blankLines) {
      // Oops, found blank lines, so it's not a title.
      // Put back the parenthetical statement we stole.
      return blankLines + title;

    } else {
      if (title) {
        globals.gTitles[linkId] = title.replace(/"|'/g, '&quot;');
      }
      if (options.parseImgDimensions && width && height) {
        globals.gDimensions[linkId] = {
          width:  width,
          height: height
        };
      }
    }
    // Completely remove the definition from the text
    return '';
  });

  // attacklab: strip sentinel
  text = text.replace(/~0/, '');

  return text;
});