const CodeMirror = require('codemirror')


CodeMirror.defineMode("kotlin", function(config, parserConfig) {
  function words(str) {
    var obj = {},
      words = str.split(" ");
    for (var i = 0; i < words.length; ++i) obj[words[i]] = true;
    return obj;
  }

  var multiLineStrings = parserConfig.multiLineStrings;

  var keywords = words(
    "package continue return object while break class data trait throw super " +
    "when type this else This try val var fun for is in if do as true false null get set " +
    "import where by get set abstract enum open annotation override private public internal " +
    "protected catch out vararg inline finally final ref const");
  var blockKeywords = words("catch class do else finally for if where try while enum");
  var atoms = words("null true false this");
  var builtins = words(
    "Int Double Float Long Short Byte IntArray ShortArray ByteArray String Boolean List Set " +
    "Map MutableList MutableSet print println shl shr ushr and or xor inv ");

  var curPunc;

  function tokenBase(stream, state) {
    var ch = stream.next();

    if (ch == '"' || ch == "'") {
      return startString(ch, stream, state);
    }

    // Wildcard import w/o trailing semicolon (import smth.*)
    if (ch == "." && stream.eat("*")) {
      return "word";
    }

    if (/[\[\]{}\(\),;\:\.]/.test(ch)) {
      curPunc = ch;
      return null;
    }

    if (/\d/.test(ch)) {
      if (stream.eat(/eE/)) {
        stream.eat(/\+\-/);
        stream.eatWhile(/\d/);
      }

      return "number";
    }

    if (ch == "/") {
      if (stream.eat("*")) {
        state.tokenize.push(tokenComment);
        return tokenComment(stream, state);
      }

      if (stream.eat("/")) {
        stream.skipToEnd();
        return "comment";
      }

      if (expectExpression(state.lastToken)) {
        return startString(ch, stream, state);
      }
    }

    // Commented
    if (ch == "-" && stream.eat(">")) {
      curPunc = "->";
      return null;
    }

    if (/[\-+*&%=<>!?|\/~]/.test(ch)) {
      stream.eatWhile(/[\-+*&%=<>|~]/);
      return "operator";
    }

    stream.eatWhile(/[\w\$_]/);

    var cur = stream.current();

    if (atoms.propertyIsEnumerable(cur)) {
      return "atom";
    }

    if (keywords.propertyIsEnumerable(cur)) {
      if (blockKeywords.propertyIsEnumerable(cur)) curPunc = "newstatement";
      return "keyword";
    }

    if (builtins.propertyIsEnumerable(cur)) {
      return "builtin";
    }

    return "word";
  }

  tokenBase.isBase = true;

  function startString(quote, stream, state) {
    var tripleQuoted = false;
    if (quote != "/" && stream.eat(quote)) {
      if (stream.eat(quote)) tripleQuoted = true;
      else return "string";
    }

    function t(stream, state) {
      var escaped = false,
        next, end = !tripleQuoted;

      while ((next = stream.next()) != null) {
        if (next == quote && !escaped) {
          if (!tripleQuoted) {
            break;
          }

          if (stream.match(quote + quote)) {
            end = true;
            break;
          }
        }

        if (quote == '"' && next == "$" && !escaped && stream.eat("{")) {
          state.tokenize.push(tokenBaseUntilBrace());
          return "string";
        }

        if (next == "$" && !escaped && !stream.eat(" ")) {
          state.tokenize.push(tokenBaseUntilSpace());
          return "string";
        }
        escaped = !escaped && next == "\\";
      }

      if (multiLineStrings)
        state.tokenize.push(t);

      if (end) state.tokenize.pop();

      return "string";
    }

    state.tokenize.push(t);
    return t(stream, state);
  }

  function tokenBaseUntilBrace() {
    var depth = 1;

    function t(stream, state) {
      if (stream.peek() == "}") {
        depth--;
        if (depth == 0) {
          state.tokenize.pop();
          return state.tokenize[state.tokenize.length - 1](stream, state);
        }
      } else if (stream.peek() == "{") {
        depth++;
      }

      return tokenBase(stream, state);
    }

    t.isBase = true;
    return t;
  }

  function tokenBaseUntilSpace() {
    function t(stream, state) {
      if (stream.eat(/[\w]/)) {
        var isWord = stream.eatWhile(/[\w]/);
        if (isWord) {
          state.tokenize.pop();
          return "word";
        }
      }
      state.tokenize.pop();
      return "string";
    }

    t.isBase = true;
    return t;
  }

  function tokenComment(stream, state) {
    var maybeEnd = false,
      ch;
    while (ch = stream.next()) {
      if (ch == "/" && maybeEnd) {
        state.tokenize.pop();
        break;
      }

      maybeEnd = (ch == "*");
    }

    return "comment";
  }

  function expectExpression(last) {
    return !last || last == "operator" || last == "->" || /[\.\[\{\(,;:]/.test(last) ||
      last == "newstatement" || last == "keyword" || last == "proplabel";
  }

  function Context(indented, column, type, align, prev) {
    this.indented = indented;
    this.column = column;
    this.type = type;
    this.align = align;
    this.prev = prev;
  }

  function pushContext(state, col, type) {
    return state.context = new Context(state.indented, col, type, null, state.context);
  }

  function popContext(state) {
    var t = state.context.type;
    if (t == ")" || t == "]" || t == "}")
      state.indented = state.context.indented;
    return state.context = state.context.prev;
  }

  // Interface

  return {
    startState: function(basecolumn) {
      return {
        tokenize: [tokenBase],
        context: new Context((basecolumn || 0) - config.indentUnit, 0, "top", false),
        indented: 0,
        startOfLine: true,
        lastToken: null
      };
    },

    token: function(stream, state) {
      var ctx = state.context;
      if (stream.sol()) {
        if (ctx.align == null) ctx.align = false;
        state.indented = stream.indentation();
        state.startOfLine = true;
        // Automatic semicolon insertion
        if (ctx.type == "statement" && !expectExpression(state.lastToken)) {
          popContext(state);
          ctx = state.context;
        }
      }
      if (stream.eatSpace()) return null;
      curPunc = null;
      var style = state.tokenize[state.tokenize.length - 1](stream, state);
      if (style == "comment") return style;
      if (ctx.align == null) ctx.align = true;
      if ((curPunc == ";" || curPunc == ":") && ctx.type == "statement") popContext(state);
      // Handle indentation for {x -> \n ... }
      else if (curPunc == "->" && ctx.type == "statement" && ctx.prev.type == "}") {
        popContext(state);
        state.context.align = false;
      } else if (curPunc == "{") pushContext(state, stream.column(), "}");
      else if (curPunc == "[") pushContext(state, stream.column(), "]");
      else if (curPunc == "(") pushContext(state, stream.column(), ")");
      else if (curPunc == "}") {
        while (ctx.type == "statement") ctx = popContext(state);
        if (ctx.type == "}") ctx = popContext(state);
        while (ctx.type == "statement") ctx = popContext(state);
      } else if (curPunc == ctx.type) popContext(state);
      else if (ctx.type == "}" || ctx.type == "top" || (ctx.type == "statement" && curPunc == "newstatement"))
        pushContext(state, stream.column(), "statement");
      state.startOfLine = false;
      state.lastToken = curPunc || style;
      return style;
    },

    indent: function(state, textAfter) {
      if (!state.tokenize[state.tokenize.length - 1].isBase) return 0;
      var firstChar = textAfter && textAfter.charAt(0),
        ctx = state.context;
      if (ctx.type == "statement" && !expectExpression(state.lastToken)) ctx = ctx.prev;
      var closing = firstChar == ctx.type;
      if (ctx.type == "statement") {
        return ctx.indented + (firstChar == "{" ? 0 : config.indentUnit);
      } else if (ctx.align) return ctx.column + (closing ? 0 : 1);
      else return ctx.indented + (closing ? 0 : config.indentUnit);
    },

    closeBrackets: {
      triples: "'\""
    },
    electricChars: "{}"
  };
});

CodeMirror.defineMIME("text/x-kotlin", "kotlin");