(function (Prism) {
  var funcPattern = /\\(?:[^a-z()[\]]|[a-z*]+)/i;
  var insideEqu = {
    'equation-command': {
      pattern: funcPattern,
      alias: 'regex',
    },
  };

  Prism.languages.latex = {
    comment: /%.*/,
    // the verbatim environment prints whitespace to the document
    cdata: {
      pattern:
        /(\\begin\{((?:lstlisting|verbatim)\*?)\})[\s\S]*?(?=\\end\{\2\})/,
      lookbehind: true,
    },
    /*
     * equations can be between $$ $$ or $ $ or \( \) or \[ \]
     * (all are multiline)
     */
    equation: [
      {
        pattern:
          /\$\$(?:\\[\s\S]|[^\\$])+\$\$|\$(?:\\[\s\S]|[^\\$])+\$|\\\([\s\S]*?\\\)|\\\[[\s\S]*?\\\]/,
        inside: insideEqu,
        alias: 'string',
      },
      {
        pattern:
          /(\\begin\{((?:align|eqnarray|equation|gather|math|multline)\*?)\})[\s\S]*?(?=\\end\{\2\})/,
        lookbehind: true,
        inside: insideEqu,
        alias: 'string',
      },
    ],
    /*
     * arguments which are keywords or references are highlighted
     * as keywords
     */
    keyword: {
      pattern:
        /(\\(?:begin|cite|documentclass|end|label|ref|usepackage)(?:\[[^\]]+\])?\{)[^}]+(?=\})/,
      lookbehind: true,
    },
    url: {
      pattern: /(\\url\{)[^}]+(?=\})/,
      lookbehind: true,
    },
    /*
     * section or chapter headlines are highlighted as bold so that
     * they stand out more
     */
    headline: {
      pattern:
        /(\\(?:chapter|frametitle|paragraph|part|section|subparagraph|subsection|subsubparagraph|subsubsection|subsubsubparagraph)\*?(?:\[[^\]]+\])?\{)[^}]+(?=\})/,
      lookbehind: true,
      alias: 'class-name',
    },
    function: {
      pattern: funcPattern,
      alias: 'selector',
    },
    punctuation: /[[\]{}&]/,
  };

  Prism.languages.tex = Prism.languages.latex;
  Prism.languages.context = Prism.languages.latex;
})(Prism);