path: root/public/prism/prism-markdown.js

(function (Prism) {
  // Allow only one line break
  var inner = /(?:\\.|[^\\\n\r]|(?:\n|\r\n?)(?![\r\n]))/.source;

  /**
   * This function is intended for the creation of the bold or italic pattern.
   *
   * This also adds a lookbehind group to the given pattern to ensure that the pattern is not backslash-escaped.
   *
   * _Note:_ Keep in mind that this adds a capturing group.
   *
   * @param {string} pattern
   * @returns {RegExp}
   */
  function createInline(pattern) {
    pattern = pattern.replace(/<inner>/g, function () {
      return inner;
    });
    return RegExp(/((?:^|[^\\])(?:\\{2})*)/.source + '(?:' + pattern + ')');
  }

  var tableCell = /(?:\\.|``(?:[^`\r\n]|`(?!`))+``|`[^`\r\n]+`|[^\\|\r\n`])+/
    .source;
  var tableRow = /\|?__(?:\|__)+\|?(?:(?:\n|\r\n?)|(?![\s\S]))/.source.replace(
    /__/g,
    function () {
      return tableCell;
    }
  );
  var tableLine =
    /\|?[ \t]*:?-{3,}:?[ \t]*(?:\|[ \t]*:?-{3,}:?[ \t]*)+\|?(?:\n|\r\n?)/
      .source;

  Prism.languages.markdown = Prism.languages.extend('markup', {});
  Prism.languages.insertBefore('markdown', 'prolog', {
    'front-matter-block': {
      pattern: /(^(?:\s*[\r\n])?)---(?!.)[\s\S]*?[\r\n]---(?!.)/,
      lookbehind: true,
      greedy: true,
      inside: {
        punctuation: /^---|---$/,
        'front-matter': {
          pattern: /\S+(?:\s+\S+)*/,
          alias: ['yaml', 'language-yaml'],
          inside: Prism.languages.yaml,
        },
      },
    },
    blockquote: {
      // > ...
      pattern: /^>(?:[\t ]*>)*/m,
      alias: 'punctuation',
    },
    table: {
      pattern: RegExp(
        '^' + tableRow + tableLine + '(?:' + tableRow + ')*',
        'm'
      ),
      inside: {
        'table-data-rows': {
          pattern: RegExp(
            '^(' + tableRow + tableLine + ')(?:' + tableRow + ')*$'
          ),
          lookbehind: true,
          inside: {
            'table-data': {
              pattern: RegExp(tableCell),
              inside: Prism.languages.markdown,
            },
            punctuation: /\|/,
          },
        },
        'table-line': {
          pattern: RegExp('^(' + tableRow + ')' + tableLine + '$'),
          lookbehind: true,
          inside: {
            punctuation: /\||:?-{3,}:?/,
          },
        },
        'table-header-row': {
          pattern: RegExp('^' + tableRow + '$'),
          inside: {
            'table-header': {
              pattern: RegExp(tableCell),
              alias: 'important',
              inside: Prism.languages.markdown,
            },
            punctuation: /\|/,
          },
        },
      },
    },
    code: [
      {
        // Prefixed by 4 spaces or 1 tab and preceded by an empty line
        pattern:
          /((?:^|\n)[ \t]*\n|(?:^|\r\n?)[ \t]*\r\n?)(?: {4}|\t).+(?:(?:\n|\r\n?)(?: {4}|\t).+)*/,
        lookbehind: true,
        alias: 'keyword',
      },
      {
        // ```optional language
        // code block
        // ```
        pattern: /^```[\s\S]*?^```$/m,
        greedy: true,
        inside: {
          'code-block': {
            pattern: /^(```.*(?:\n|\r\n?))[\s\S]+?(?=(?:\n|\r\n?)^```$)/m,
            lookbehind: true,
          },
          'code-language': {
            pattern: /^(```).+/,
            lookbehind: true,
          },
          punctuation: /```/,
        },
      },
    ],
    title: [
      {
        // title 1
        // =======

        // title 2
        // -------
        pattern: /\S.*(?:\n|\r\n?)(?:==+|--+)(?=[ \t]*$)/m,
        alias: 'important',
        inside: {
          punctuation: /==+$|--+$/,
        },
      },
      {
        // # title 1
        // ###### title 6
        pattern: /(^\s*)#.+/m,
        lookbehind: true,
        alias: 'important',
        inside: {
          punctuation: /^#+|#+$/,
        },
      },
    ],
    hr: {
      // ***
      // ---
      // * * *
      // -----------
      pattern: /(^\s*)([*-])(?:[\t ]*\2){2,}(?=\s*$)/m,
      lookbehind: true,
      alias: 'punctuation',
    },
    list: {
      // * item
      // + item
      // - item
      // 1. item
      pattern: /(^\s*)(?:[*+-]|\d+\.)(?=[\t ].)/m,
      lookbehind: true,
      alias: 'punctuation',
    },
    'url-reference': {
      // [id]: http://example.com "Optional title"
      // [id]: http://example.com 'Optional title'
      // [id]: http://example.com (Optional title)
      // [id]: <http://example.com> "Optional title"
      pattern:
        /!?\[[^\]]+\]:[\t ]+(?:\S+|<(?:\\.|[^>\\])+>)(?:[\t ]+(?:"(?:\\.|[^"\\])*"|'(?:\\.|[^'\\])*'|\((?:\\.|[^)\\])*\)))?/,
      inside: {
        variable: {
          pattern: /^(!?\[)[^\]]+/,
          lookbehind: true,
        },
        string: /(?:"(?:\\.|[^"\\])*"|'(?:\\.|[^'\\])*'|\((?:\\.|[^)\\])*\))$/,
        punctuation: /^[\[\]!:]|[<>]/,
      },
      alias: 'url',
    },
    bold: {
      // **strong**
      // __strong__

      // allow one nested instance of italic text using the same delimiter
      pattern: createInline(
        /\b__(?:(?!_)<inner>|_(?:(?!_)<inner>)+_)+__\b|\*\*(?:(?!\*)<inner>|\*(?:(?!\*)<inner>)+\*)+\*\*/
          .source
      ),
      lookbehind: true,
      greedy: true,
      inside: {
        content: {
          pattern: /(^..)[\s\S]+(?=..$)/,
          lookbehind: true,
          inside: {}, // see below
        },
        punctuation: /\*\*|__/,
      },
    },
    italic: {
      // *em*
      // _em_

      // allow one nested instance of bold text using the same delimiter
      pattern: createInline(
        /\b_(?:(?!_)<inner>|__(?:(?!_)<inner>)+__)+_\b|\*(?:(?!\*)<inner>|\*\*(?:(?!\*)<inner>)+\*\*)+\*/
          .source
      ),
      lookbehind: true,
      greedy: true,
      inside: {
        content: {
          pattern: /(^.)[\s\S]+(?=.$)/,
          lookbehind: true,
          inside: {}, // see below
        },
        punctuation: /[*_]/,
      },
    },
    strike: {
      // ~~strike through~~
      // ~strike~
      // eslint-disable-next-line regexp/strict
      pattern: createInline(/(~~?)(?:(?!~)<inner>)+\2/.source),
      lookbehind: true,
      greedy: true,
      inside: {
        content: {
          pattern: /(^~~?)[\s\S]+(?=\1$)/,
          lookbehind: true,
          inside: {}, // see below
        },
        punctuation: /~~?/,
      },
    },
    'code-snippet': {
      // `code`
      // ``code``
      pattern:
        /(^|[^\\`])(?:``[^`\r\n]+(?:`[^`\r\n]+)*``(?!`)|`[^`\r\n]+`(?!`))/,
      lookbehind: true,
      greedy: true,
      alias: ['code', 'keyword'],
    },
    url: {
      // [example](http://example.com "Optional title")
      // [example][id]
      // [example] [id]
      pattern: createInline(
        /!?\[(?:(?!\])<inner>)+\](?:\([^\s)]+(?:[\t ]+"(?:\\.|[^"\\])*")?\)|[ \t]?\[(?:(?!\])<inner>)+\])/
          .source
      ),
      lookbehind: true,
      greedy: true,
      inside: {
        operator: /^!/,
        content: {
          pattern: /(^\[)[^\]]+(?=\])/,
          lookbehind: true,
          inside: {}, // see below
        },
        variable: {
          pattern: /(^\][ \t]?\[)[^\]]+(?=\]$)/,
          lookbehind: true,
        },
        url: {
          pattern: /(^\]\()[^\s)]+/,
          lookbehind: true,
        },
        string: {
          pattern: /(^[ \t]+)"(?:\\.|[^"\\])*"(?=\)$)/,
          lookbehind: true,
        },
      },
    },
  });

  ['url', 'bold', 'italic', 'strike'].forEach(function (token) {
    ['url', 'bold', 'italic', 'strike', 'code-snippet'].forEach(function (
      inside
    ) {
      if (token !== inside) {
        Prism.languages.markdown[token].inside.content.inside[inside] =
          Prism.languages.markdown[inside];
      }
    });
  });

  Prism.hooks.add('after-tokenize', function (env) {
    if (env.language !== 'markdown' && env.language !== 'md') {
      return;
    }

    function walkTokens(tokens) {
      if (!tokens || typeof tokens === 'string') {
        return;
      }

      for (var i = 0, l = tokens.length; i < l; i++) {
        var token = tokens[i];

        if (token.type !== 'code') {
          walkTokens(token.content);
          continue;
        }

        /*
         * Add the correct `language-xxxx` class to this code block. Keep in mind that the `code-language` token
         * is optional. But the grammar is defined so that there is only one case we have to handle:
         *
         * token.content = [
         *     <span class="punctuation">```</span>,
         *     <span class="code-language">xxxx</span>,
         *     '\n', // exactly one new lines (\r or \n or \r\n)
         *     <span class="code-block">...</span>,
         *     '\n', // exactly one new lines again
         *     <span class="punctuation">```</span>
         * ];
         */

        var codeLang = token.content[1];
        var codeBlock = token.content[3];

        if (
          codeLang &&
          codeBlock &&
          codeLang.type === 'code-language' &&
          codeBlock.type === 'code-block' &&
          typeof codeLang.content === 'string'
        ) {
          // this might be a language that Prism does not support

          // do some replacements to support C++, C#, and F#
          var lang = codeLang.content
            .replace(/\b#/g, 'sharp')
            .replace(/\b\+\+/g, 'pp');
          // only use the first word
          lang = (/[a-z][\w-]*/i.exec(lang) || [''])[0].toLowerCase();
          var alias = 'language-' + lang;

          // add alias
          if (!codeBlock.alias) {
            codeBlock.alias = [alias];
          } else if (typeof codeBlock.alias === 'string') {
            codeBlock.alias = [codeBlock.alias, alias];
          } else {
            codeBlock.alias.push(alias);
          }
        }
      }
    }

    walkTokens(env.tokens);
  });

  Prism.hooks.add('wrap', function (env) {
    if (env.type !== 'code-block') {
      return;
    }

    var codeLang = '';
    for (var i = 0, l = env.classes.length; i < l; i++) {
      var cls = env.classes[i];
      var match = /language-(.+)/.exec(cls);
      if (match) {
        codeLang = match[1];
        break;
      }
    }

    var grammar = Prism.languages[codeLang];

    if (!grammar) {
      if (codeLang && codeLang !== 'none' && Prism.plugins.autoloader) {
        var id =
          'md-' + new Date().valueOf() + '-' + Math.floor(Math.random() * 1e16);
        env.attributes['id'] = id;

        Prism.plugins.autoloader.loadLanguages(codeLang, function () {
          var ele = document.getElementById(id);
          if (ele) {
            ele.innerHTML = Prism.highlight(
              ele.textContent,
              Prism.languages[codeLang],
              codeLang
            );
          }
        });
      }
    } else {
      env.content = Prism.highlight(
        textContent(env.content),
        grammar,
        codeLang
      );
    }
  });

  var tagPattern = RegExp(Prism.languages.markup.tag.pattern.source, 'gi');

  /**
   * A list of known entity names.
   *
   * This will always be incomplete to save space. The current list is the one used by lowdash's unescape function.
   *
   * @see {@link https://github.com/lodash/lodash/blob/2da024c3b4f9947a48517639de7560457cd4ec6c/unescape.js#L2}
   */
  var KNOWN_ENTITY_NAMES = {
    amp: '&',
    lt: '<',
    gt: '>',
    quot: '"',
  };

  // IE 11 doesn't support `String.fromCodePoint`
  var fromCodePoint = String.fromCodePoint || String.fromCharCode;

  /**
   * Returns the text content of a given HTML source code string.
   *
   * @param {string} html
   * @returns {string}
   */
  function textContent(html) {
    // remove all tags
    var text = html.replace(tagPattern, '');

    // decode known entities
    text = text.replace(/&(\w{1,8}|#x?[\da-f]{1,8});/gi, function (m, code) {
      code = code.toLowerCase();

      if (code[0] === '#') {
        var value;
        if (code[1] === 'x') {
          value = parseInt(code.slice(2), 16);
        } else {
          value = Number(code.slice(1));
        }

        return fromCodePoint(value);
      } else {
        var known = KNOWN_ENTITY_NAMES[code];
        if (known) {
          return known;
        }

        // unable to decode
        return m;
      }
    });

    return text;
  }

  Prism.languages.md = Prism.languages.markdown;
})(Prism);