/*

 * Copyright (C) 2009 Apple Inc. All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY

 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR

 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY

 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 

 */

#ifndef LiteralParser_h

#define LiteralParser_h

#include "JSGlobalObjectFunctions.h"

#include "JSValue.h"

#include "UString.h"

namespace JSC {

    class LiteralParser {

    public:

        typedef enum { StrictJSON, NonStrictJSON } ParserMode;

        LiteralParser(ExecState* exec, const UString& s, ParserMode mode)

            : m_exec(exec)

            , m_lexer(s, mode)

            , m_mode(mode)

        {

        }

        JSValue tryLiteralParse()

        {

            m_lexer.next();

            JSValue result = parse(m_mode == StrictJSON ? StartParseExpression : StartParseStatement);

            if (m_lexer.currentToken().type != TokEnd)

                return JSValue();

            return result;

        }

    private:

        enum ParserState { StartParseObject, StartParseArray, StartParseExpression, 

                           StartParseStatement, StartParseStatementEndStatement, 

                           DoParseObjectStartExpression, DoParseObjectEndExpression,

                           DoParseArrayStartExpression, DoParseArrayEndExpression };

        enum TokenType { TokLBracket, TokRBracket, TokLBrace, TokRBrace, 

                         TokString, TokIdentifier, TokNumber, TokColon, 

                         TokLParen, TokRParen, TokComma, TokTrue, TokFalse,

                         TokNull, TokEnd, TokError };

        class Lexer {

        public:

            struct LiteralParserToken {

                TokenType type;

                const UChar* start;

                const UChar* end;

                UString stringToken;

                double numberToken;

            };

            Lexer(const UString& s, ParserMode mode)

                : m_string(s)

                , m_mode(mode)

                , m_ptr(s.data())

                , m_end(s.data() + s.size())

            {

            }

            TokenType next()

            {

                return lex(m_currentToken);

            }

            const LiteralParserToken& currentToken()

            {

                return m_currentToken;

            }

        private:

            TokenType lex(LiteralParserToken&);

            template <ParserMode mode> TokenType lexString(LiteralParserToken&);

            TokenType lexNumber(LiteralParserToken&);

            LiteralParserToken m_currentToken;

            UString m_string;

            ParserMode m_mode;

            const UChar* m_ptr;

            const UChar* m_end;

        };

        class StackGuard;

        JSValue parse(ParserState);

        ExecState* m_exec;

        LiteralParser::Lexer m_lexer;

        ParserMode m_mode;

    };

}

#endif