(function (Prism) {
  var interpolationExpr = {
    pattern: /[\s\S]+/,
    inside: null,
  };

  Prism.languages.v = Prism.languages.extend('clike', {
    string: {
      pattern: /r?(["'])(?:\\(?:\r\n|[\s\S])|(?!\1)[^\\\r\n])*\1/,
      alias: 'quoted-string',
      greedy: true,
      inside: {
        interpolation: {
          pattern:
            /((?:^|[^\\])(?:\\{2})*)\$(?:\{[^{}]*\}|\w+(?:\.\w+(?:\([^\(\)]*\))?|\[[^\[\]]+\])*)/,
          lookbehind: true,
          inside: {
            'interpolation-variable': {
              pattern: /^\$\w[\s\S]*$/,
              alias: 'variable',
            },
            'interpolation-punctuation': {
              pattern: /^\$\{|\}$/,
              alias: 'punctuation',
            },
            'interpolation-expression': interpolationExpr,
          },
        },
      },
    },
    'class-name': {
      pattern: /(\b(?:enum|interface|struct|type)\s+)(?:C\.)?\w+/,
      lookbehind: true,
    },
    keyword:
      /(?:\b(?:__global|as|asm|assert|atomic|break|chan|const|continue|defer|else|embed|enum|fn|for|go(?:to)?|if|import|in|interface|is|lock|match|module|mut|none|or|pub|return|rlock|select|shared|sizeof|static|struct|type(?:of)?|union|unsafe)|\$(?:else|for|if)|#(?:flag|include))\b/,
    number:
      /\b(?:0x[a-f\d]+(?:_[a-f\d]+)*|0b[01]+(?:_[01]+)*|0o[0-7]+(?:_[0-7]+)*|\d+(?:_\d+)*(?:\.\d+(?:_\d+)*)?)\b/i,
    operator:
      /~|\?|[*\/%^!=]=?|\+[=+]?|-[=-]?|\|[=|]?|&(?:=|&|\^=?)?|>(?:>=?|=)?|<(?:<=?|=|-)?|:=|\.\.\.?/,
    builtin:
      /\b(?:any(?:_float|_int)?|bool|byte(?:ptr)?|charptr|f(?:32|64)|i(?:8|16|64|128|nt)|rune|size_t|string|u(?:16|32|64|128)|voidptr)\b/,
  });

  interpolationExpr.inside = Prism.languages.v;

  Prism.languages.insertBefore('v', 'string', {
    char: {
      pattern: /`(?:\\`|\\?[^`]{1,2})`/, // using {1,2} instead of `u` flag for compatibility
      alias: 'rune',
    },
  });

  Prism.languages.insertBefore('v', 'operator', {
    attribute: {
      pattern:
        /(^[\t ]*)\[(?:deprecated|direct_array_access|flag|inline|live|ref_only|typedef|unsafe_fn|windows_stdcall)\]/m,
      lookbehind: true,
      alias: 'annotation',
      inside: {
        punctuation: /[\[\]]/,
        keyword: /\w+/,
      },
    },
    generic: {
      pattern: /<\w+>(?=\s*[\)\{])/,
      inside: {
        punctuation: /[<>]/,
        'class-name': /\w+/,
      },
    },
  });

  Prism.languages.insertBefore('v', 'function', {
    'generic-function': {
      // e.g. foo<T>( ...
      pattern: /\b\w+\s*<\w+>(?=\()/,
      inside: {
        function: /^\w+/,
        generic: {
          pattern: /<\w+>/,
          inside: Prism.languages.v.generic.inside,
        },
      },
    },
  });
})(Prism);