'use client';
function wordRegExp(words, end) {
  return new RegExp((end ? "" : "^") + "(?:" + words.join("|") + ")" + (end ? "$" : "\\b"));
}

function chain(tokenize, stream, state) {
  state.tokenize.push(tokenize);
  return tokenize(stream, state);
}

var operators = /^(?:[-+/%|&^]|\*\*?|[<>]{2})/;
var conditionalOperators = /^(?:[=!]~|===|<=>|[<>=!]=?|[|&]{2}|~)/;
var indexingOperators = /^(?:\[\][?=]?)/;
var anotherOperators = /^(?:\.(?:\.{2})?|->|[?:])/;
var idents = /^[a-z_\u009F-\uFFFF][a-zA-Z0-9_\u009F-\uFFFF]*/;
var types = /^[A-Z_\u009F-\uFFFF][a-zA-Z0-9_\u009F-\uFFFF]*/;
var keywords = wordRegExp([
  "abstract", "alias", "as", "asm", "begin", "break", "case", "class", "def", "do",
  "else", "elsif", "end", "ensure", "enum", "extend", "for", "fun", "if",
  "include", "instance_sizeof", "lib", "macro", "module", "next", "of", "out", "pointerof",
  "private", "protected", "rescue", "return", "require", "select", "sizeof", "struct",
  "super", "then", "type", "typeof", "uninitialized", "union", "unless", "until", "when", "while", "with",
  "yield", "__DIR__", "__END_LINE__", "__FILE__", "__LINE__"
]);
var atomWords = wordRegExp(["true", "false", "nil", "self"]);
var indentKeywordsArray = [
  "def", "fun", "macro",
  "class", "module", "struct", "lib", "enum", "union",
  "do", "for"
];
var indentKeywords = wordRegExp(indentKeywordsArray);
var indentExpressionKeywordsArray = ["if", "unless", "case", "while", "until", "begin", "then"];
var indentExpressionKeywords = wordRegExp(indentExpressionKeywordsArray);
var dedentKeywordsArray = ["end", "else", "elsif", "rescue", "ensure"];
var dedentKeywords = wordRegExp(dedentKeywordsArray);
var dedentPunctualsArray = ["\\)", "\\}", "\\]"];
var dedentPunctuals = new RegExp("^(?:" + dedentPunctualsArray.join("|") + ")$");
var nextTokenizer = {
  "def": tokenFollowIdent, "fun": tokenFollowIdent, "macro": tokenMacroDef,
  "class": tokenFollowType, "module": tokenFollowType, "struct": tokenFollowType,
  "lib": tokenFollowType, "enum": tokenFollowType, "union": tokenFollowType
};
var matching = {"[": "]", "{": "}", "(": ")", "<": ">"};

function tokenBase(stream, state) {
  if (stream.eatSpace()) {
    return null;
  }

  // Macros
  if (state.lastToken != "\\" && stream.match("{%", false)) {
    return chain(tokenMacro("%", "%"), stream, state);
  }

  if (state.lastToken != "\\" && stream.match("{{", false)) {
    return chain(tokenMacro("{", "}"), stream, state);
  }

  // Comments
  if (stream.peek() == "#") {
    stream.skipToEnd();
    return "comment";
  }

  // Variables and keywords
  var matched;
  if (stream.match(idents)) {
    stream.eat(/[?!]/);

    matched = stream.current();
    if (stream.eat(":")) {
      return "atom";
    } else if (state.lastToken == ".") {
      return "property";
    } else if (keywords.test(matched)) {
      if (indentKeywords.test(matched)) {
        if (!(matched == "fun" && state.blocks.indexOf("lib") >= 0) && !(matched == "def" && state.lastToken == "abstract")) {
          state.blocks.push(matched);
          state.currentIndent += 1;
        }
      } else if ((state.lastStyle == "operator" || !state.lastStyle) && indentExpressionKeywords.test(matched)) {
        state.blocks.push(matched);
        state.currentIndent += 1;
      } else if (matched == "end") {
        state.blocks.pop();
        state.currentIndent -= 1;
      }

      if (nextTokenizer.hasOwnProperty(matched)) {
        state.tokenize.push(nextTokenizer[matched]);
      }

      return "keyword";
    } else if (atomWords.test(matched)) {
      return "atom";
    }

    return "variable";
  }

  // Class variables and instance variables
  // or attributes
  if (stream.eat("@")) {
    if (stream.peek() == "[") {
      return chain(tokenNest("[", "]", "meta"), stream, state);
    }

    stream.eat("@");
    stream.match(idents) || stream.match(types);
    return "propertyName";
  }

  // Constants and types
  if (stream.match(types)) {
    return "tag";
  }

  // Symbols or ':' operator
  if (stream.eat(":")) {
    if (stream.eat("\"")) {
      return chain(tokenQuote("\"", "atom", false), stream, state);
    } else if (stream.match(idents) || stream.match(types) ||
               stream.match(operators) || stream.match(conditionalOperators) || stream.match(indexingOperators)) {
      return "atom";
    }
    stream.eat(":");
    return "operator";
  }

  // Strings
  if (stream.eat("\"")) {
    return chain(tokenQuote("\"", "string", true), stream, state);
  }

  // Strings or regexps or macro variables or '%' operator
  if (stream.peek() == "%") {
    var style = "string";
    var embed = true;
    var delim;

    if (stream.match("%r")) {
      // Regexps
      style = "string.special";
      delim = stream.next();
    } else if (stream.match("%w")) {
      embed = false;
      delim = stream.next();
    } else if (stream.match("%q")) {
      embed = false;
      delim = stream.next();
    } else {
      if(delim = stream.match(/^%([^\w\s=])/)) {
        delim = delim[1];
      } else if (stream.match(/^%[a-zA-Z_\u009F-\uFFFF][\w\u009F-\uFFFF]*/)) {
        // Macro variables
        return "meta";
      } else if (stream.eat('%')) {
        // '%' operator
        return "operator";
      }
    }

    if (matching.hasOwnProperty(delim)) {
      delim = matching[delim];
    }
    return chain(tokenQuote(delim, style, embed), stream, state);
  }

  // Here Docs
  if (matched = stream.match(/^<<-('?)([A-Z]\w*)\1/)) {
    return chain(tokenHereDoc(matched[2], !matched[1]), stream, state)
  }

  // Characters
  if (stream.eat("'")) {
    stream.match(/^(?:[^']|\\(?:[befnrtv0'"]|[0-7]{3}|u(?:[0-9a-fA-F]{4}|\{[0-9a-fA-F]{1,6}\})))/);
    stream.eat("'");
    return "atom";
  }

  // Numbers
  if (stream.eat("0")) {
    if (stream.eat("x")) {
      stream.match(/^[0-9a-fA-F_]+/);
    } else if (stream.eat("o")) {
      stream.match(/^[0-7_]+/);
    } else if (stream.eat("b")) {
      stream.match(/^[01_]+/);
    }
    return "number";
  }

  if (stream.eat(/^\d/)) {
    stream.match(/^[\d_]*(?:\.[\d_]+)?(?:[eE][+-]?\d+)?/);
    return "number";
  }

  // Operators
  if (stream.match(operators)) {
    stream.eat("="); // Operators can follow assign symbol.
    return "operator";
  }

  if (stream.match(conditionalOperators) || stream.match(anotherOperators)) {
    return "operator";
  }

  // Parens and braces
  if (matched = stream.match(/[({[]/, false)) {
    matched = matched[0];
    return chain(tokenNest(matched, matching[matched], null), stream, state);
  }

  // Escapes
  if (stream.eat("\\")) {
    stream.next();
    return "meta";
  }

  stream.next();
  return null;
}

function tokenNest(begin, end, style, started) {
  return function (stream, state) {
    if (!started && stream.match(begin)) {
      state.tokenize[state.tokenize.length - 1] = tokenNest(begin, end, style, true);
      state.currentIndent += 1;
      return style;
    }

    var nextStyle = tokenBase(stream, state);
    if (stream.current() === end) {
      state.tokenize.pop();
      state.currentIndent -= 1;
      nextStyle = style;
    }

    return nextStyle;
  };
}

function tokenMacro(begin, end, started) {
  return function (stream, state) {
    if (!started && stream.match("{" + begin)) {
      state.currentIndent += 1;
      state.tokenize[state.tokenize.length - 1] = tokenMacro(begin, end, true);
      return "meta";
    }

    if (stream.match(end + "}")) {
      state.currentIndent -= 1;
      state.tokenize.pop();
      return "meta";
    }

    return tokenBase(stream, state);
  };
}

function tokenMacroDef(stream, state) {
  if (stream.eatSpace()) {
    return null;
  }

  var matched;
  if (matched = stream.match(idents)) {
    if (matched == "def") {
      return "keyword";
    }
    stream.eat(/[?!]/);
  }

  state.tokenize.pop();
  return "def";
}

function tokenFollowIdent(stream, state) {
  if (stream.eatSpace()) {
    return null;
  }

  if (stream.match(idents)) {
    stream.eat(/[!?]/);
  } else {
    stream.match(operators) || stream.match(conditionalOperators) || stream.match(indexingOperators);
  }
  state.tokenize.pop();
  return "def";
}

function tokenFollowType(stream, state) {
  if (stream.eatSpace()) {
    return null;
  }

  stream.match(types);
  state.tokenize.pop();
  return "def";
}

function tokenQuote(end, style, embed) {
  return function (stream, state) {
    var escaped = false;

    while (stream.peek()) {
      if (!escaped) {
        if (stream.match("{%", false)) {
          state.tokenize.push(tokenMacro("%", "%"));
          return style;
        }

        if (stream.match("{{", false)) {
          state.tokenize.push(tokenMacro("{", "}"));
          return style;
        }

        if (embed && stream.match("#{", false)) {
          state.tokenize.push(tokenNest("#{", "}", "meta"));
          return style;
        }

        var ch = stream.next();

        if (ch == end) {
          state.tokenize.pop();
          return style;
        }

        escaped = embed && ch == "\\";
      } else {
        stream.next();
        escaped = false;
      }
    }

    return style;
  };
}

function tokenHereDoc(phrase, embed) {
  return function (stream, state) {
    if (stream.sol()) {
      stream.eatSpace();
      if (stream.match(phrase)) {
        state.tokenize.pop();
        return "string";
      }
    }

    var escaped = false;
    while (stream.peek()) {
      if (!escaped) {
        if (stream.match("{%", false)) {
          state.tokenize.push(tokenMacro("%", "%"));
          return "string";
        }

        if (stream.match("{{", false)) {
          state.tokenize.push(tokenMacro("{", "}"));
          return "string";
        }

        if (embed && stream.match("#{", false)) {
          state.tokenize.push(tokenNest("#{", "}", "meta"));
          return "string";
        }

        escaped = stream.next() == "\\" && embed;
      } else {
        stream.next();
        escaped = false;
      }
    }

    return "string";
  }
}

const crystal = {
  name: "crystal",
  startState: function () {
    return {
      tokenize: [tokenBase],
      currentIndent: 0,
      lastToken: null,
      lastStyle: null,
      blocks: []
    };
  },

  token: function (stream, state) {
    var style = state.tokenize[state.tokenize.length - 1](stream, state);
    var token = stream.current();

    if (style && style != "comment") {
      state.lastToken = token;
      state.lastStyle = style;
    }

    return style;
  },

  indent: function (state, textAfter, cx) {
    textAfter = textAfter.replace(/^\s*(?:\{%)?\s*|\s*(?:%\})?\s*$/g, "");

    if (dedentKeywords.test(textAfter) || dedentPunctuals.test(textAfter)) {
      return cx.unit * (state.currentIndent - 1);
    }

    return cx.unit * state.currentIndent;
  },

  languageData: {
    indentOnInput: wordRegExp(dedentPunctualsArray.concat(dedentKeywordsArray), true),
    commentTokens: {line: "#"}
  }
};

export { crystal };
