/*
 * Copyright © 2007 Pippijn van Steenhoven / The Ermyth Team
 * Rights to this code are as documented in doc/pod/license.pod.
 *
 * JSON-RPC for Ermyth
 *
 * $Id: reader.h,v 1.3 2007/09/05 11:23:15 pippijn Exp $
 */

//>>>>>>>>>>> reader.h <<<<<<<<<<<//
#ifndef READER_H
#define READER_H

#include <deque>
#include <stack>
#include <string>
#include <iostream>

#include "json/value.h"

namespace json
{
  class Value;

  class Reader
  {
  public:
    typedef char const *Location;

    Reader ();

    bool parse (const std::string &document, Value &root, bool collectComments = true);
    bool parse (char const *beginDoc, char const *endDOc, Value &root, bool collectComments = true);
    bool parse (std::istream &, Value &root, bool collectComments = true);

    std::string error_msgs () const;

  private:
    enum TokenType
      {
        tokenEndOfStream = 0,
        tokenObjectBegin,
        tokenObjectEnd,
        tokenArrayBegin,
        tokenArrayEnd,
        tokenString,
        tokenNumber,
        tokenTrue,
        tokenFalse,
        tokenNull,
        tokenArraySeparator,
        tokenMemberSeparator,
        tokenComment,
        tokenError
      };

    class Token
    {
    public:
      TokenType type_;
      Location start_;
      Location end_;
    };

    class ErrorInfo
    {
    public:
      Token token_;
      std::string message_;
      Location extra_;
    };

    typedef std::deque<ErrorInfo> Errors;

    bool expectToken (TokenType type, Token &token, char const *message);
    bool readToken (Token &token);
    void skipSpaces ();
    bool match (Location pattern, 
                int patternLength);
    bool readComment ();
    bool readCStyleComment ();
    bool readCppStyleComment ();
    bool readString ();
    void readNumber ();
    bool readValue ();
    bool readObject ();
    bool readArray ();
    bool decodeNumber (Token &token);
    bool decodeString (Token &token);
    bool decodeString (Token &token, std::string &decoded);
    bool decodeDouble (Token &token);
    bool decodeUnicodeEscapeSequence (Token &token, 
                                      Location &current, 
                                      Location end, 
                                      unsigned &unicode);
    bool addError (const std::string &message, 
                   Token &token,
                   Location extra = 0);
    bool recoverFromError (TokenType skipUntilToken);
    bool addErrorAndRecover (const std::string &message, 
                             Token &token,
                             TokenType skipUntilToken);
    void skipUntilSpace ();
    Value &currentValue ();
    char getNextChar ();
    void getLocationLineAndColumn (Location location,
                                   int &line,
                                   int &column) const;
    std::string getLocationLineAndColumn (Location location) const;
    void addComment (Location begin, 
                     Location end, 
                     CommentPlacement placement);
    void skipCommentTokens (Token &token);
   
    typedef std::stack<Value *> Nodes;
    Nodes nodes_;
    Errors errors_;
    std::string document_;
    Location begin_;
    Location end_;
    Location current_;
    Location lastValueEnd_;
    Value *lastValue_;
    std::string commentsBefore_;
    bool collectComments_;
  };

  std::istream& operator >> (std::istream&, Value&);

} // namespace json

#endif // READER_H