(function (Prism) {
  // https://cuelang.org/docs/references/spec/

  // eslint-disable-next-line regexp/strict
  var stringEscape = /\\(?:(?!\2)|\2(?:[^()\r\n]|\([^()]*\)))/.source;
  // eslint-disable-next-line regexp/strict
  var stringTypes =
    /"""(?:[^\\"]|"(?!""\2)|<esc>)*"""/.source +
    // eslint-disable-next-line regexp/strict
    '|' +
    /'''(?:[^\\']|'(?!''\2)|<esc>)*'''/.source +
    // eslint-disable-next-line regexp/strict
    '|' +
    /"(?:[^\\\r\n"]|"(?!\2)|<esc>)*"/.source +
    // eslint-disable-next-line regexp/strict
    '|' +
    /'(?:[^\\\r\n']|'(?!\2)|<esc>)*'/.source;
  var stringLiteral = '(?:' + stringTypes.replace(/<esc>/g, stringEscape) + ')';

  Prism.languages.cue = {
    comment: {
      pattern: /\/\/.*/,
      greedy: true,
    },
    'string-literal': {
      // eslint-disable-next-line regexp/strict
      pattern: RegExp(
        /(^|[^#"'\\])(#*)/.source + stringLiteral + /(?!["'])\2/.source
      ),
      lookbehind: true,
      greedy: true,
      inside: {
        // I'm using dirty hack here. We have to know the number hashes at the start of the string somehow,
        // but we can't look back. So instead, we will use a lookahead, go to the end of the string, and
        // capture the hashes at the end of the string.
        escape: {
          pattern:
            /(?=[\s\S]*["'](#*)$)\\\1(?:U[a-fA-F0-9]{1,8}|u[a-fA-F0-9]{1,4}|x[a-fA-F0-9]{1,2}|\d{2,3}|[^(])/,
          greedy: true,
          alias: 'string',
        },
        interpolation: {
          pattern: /(?=[\s\S]*["'](#*)$)\\\1\([^()]*\)/,
          greedy: true,
          inside: {
            punctuation: /^\\#*\(|\)$/,
            expression: {
              pattern: /[\s\S]+/,
              inside: null,
            },
          },
        },
        string: /[\s\S]+/,
      },
    },

    keyword: {
      pattern: /(^|[^\w$])(?:for|if|import|in|let|null|package)(?![\w$])/,
      lookbehind: true,
    },
    boolean: {
      pattern: /(^|[^\w$])(?:false|true)(?![\w$])/,
      lookbehind: true,
    },
    builtin: {
      pattern:
        /(^|[^\w$])(?:bool|bytes|float|float(?:32|64)|u?int(?:8|16|32|64|128)?|number|rune|string)(?![\w$])/,
      lookbehind: true,
    },

    attribute: {
      pattern: /@[\w$]+(?=\s*\()/,
      alias: 'function',
    },
    function: {
      pattern: /(^|[^\w$])[a-z_$][\w$]*(?=\s*\()/i,
      lookbehind: true,
    },

    number: {
      pattern:
        /(^|[^\w$.])(?:0b[01]+(?:_[01]+)*|0o[0-7]+(?:_[0-7]+)*|0[xX][0-9A-Fa-f]+(?:_[0-9A-Fa-f]+)*|(?:\d+(?:_\d+)*(?:\.(?:\d+(?:_\d+)*)?)?|\.\d+(?:_\d+)*)(?:[eE][+-]?\d+(?:_\d+)*)?(?:[KMGTP]i?)?)(?![\w$])/,
      lookbehind: true,
    },

    operator: /\.{3}|_\|_|&&?|\|\|?|[=!]~|[<>=!]=?|[+\-*/?]/,
    punctuation: /[()[\]{},.:]/,
  };

  Prism.languages.cue[
    'string-literal'
  ].inside.interpolation.inside.expression.inside = Prism.languages.cue;
})(Prism);