/****************************************************************************

**

** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the QtScript module of the Qt Toolkit.

**

** $QT_BEGIN_LICENSE:LGPL-ONLY$

** GNU Lesser General Public License Usage

** This file may be used under the terms of the GNU Lesser

** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

** packaging of this file.  Please review the following information to

** ensure the GNU Lesser General Public License version 2.1 requirements

** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

** $QT_END_LICENSE$

**

****************************************************************************/

#ifndef QSCRIPTLEXER_P_H

#define QSCRIPTLEXER_P_H

//

//  W A R N I N G

//  -------------

//

// This file is not part of the Qt API.  It exists purely as an

// implementation detail.  This header file may change from version to

// version without notice, or even be removed.

//

// We mean it.

//

#include <QtCore/QString>

QT_BEGIN_NAMESPACE

class QScriptEnginePrivate;

class QScriptNameIdImpl;

namespace QScript {

class Lexer

{

public:

    Lexer(QScriptEnginePrivate *eng);

    ~Lexer();

    void setCode(const QString &c, int lineno);

    int lex();

    int currentLineNo() const { return yylineno; }

    int currentColumnNo() const { return yycolumn; }

    int startLineNo() const { return startlineno; }

    int startColumnNo() const { return startcolumn; }

    int endLineNo() const { return currentLineNo(); }

    int endColumnNo() const

    { int col = currentColumnNo(); return (col > 0) ? col - 1 : col; }

    bool prevTerminator() const { return terminator; }

    enum State { Start,

                 Identifier,

                 InIdentifier,

                 InSingleLineComment,

                 InMultiLineComment,

                 InNum,

                 InNum0,

                 InHex,

                 InOctal,

                 InDecimal,

                 InExponentIndicator,

                 InExponent,

                 Hex,

                 Octal,

                 Number,

                 String,

                 Eof,

                 InString,

                 InEscapeSequence,

                 InHexEscape,

                 InUnicodeEscape,

                 Other,

                 Bad };

    enum Error {

        NoError,

        IllegalCharacter,

        UnclosedStringLiteral,

        IllegalEscapeSequence,

        IllegalUnicodeEscapeSequence,

        UnclosedComment,

        IllegalExponentIndicator,

        IllegalIdentifier

    };

    enum ParenthesesState {

        IgnoreParentheses,

        CountParentheses,

        BalancedParentheses

    };

    enum RegExpBodyPrefix {

        NoPrefix,

        EqualPrefix

    };

    bool scanRegExp(RegExpBodyPrefix prefix = NoPrefix);

    QScriptNameIdImpl *pattern;

    int flags;

    State lexerState() const

        { return state; }

    QString errorMessage() const

        { return errmsg; }

    void setErrorMessage(const QString &err)

        { errmsg = err; }

    void setErrorMessage(const char *err)

        { setErrorMessage(QString::fromLatin1(err)); }

    Error error() const

        { return err; }

    void clearError()

        { err = NoError; }

private:

    QScriptEnginePrivate *driver;

    int yylineno;

    bool done;

    char *buffer8;

    QChar *buffer16;

    uint size8, size16;

    uint pos8, pos16;

    bool terminator;

    bool restrKeyword;

    // encountered delimiter like "'" and "}" on last run

    bool delimited;

    int stackToken;

    State state;

    void setDone(State s);

    uint pos;

    void shift(uint p);

    int lookupKeyword(const char *);

    bool isWhiteSpace() const;

    bool isLineTerminator() const;

    bool isHexDigit(ushort c) const;

    bool isOctalDigit(ushort c) const;

    int matchPunctuator(ushort c1, ushort c2,

                         ushort c3, ushort c4);

    ushort singleEscape(ushort c) const;

    ushort convertOctal(ushort c1, ushort c2,

                         ushort c3) const;

public:

    static unsigned char convertHex(ushort c1);

    static unsigned char convertHex(ushort c1, ushort c2);

    static QChar convertUnicode(ushort c1, ushort c2,

                                 ushort c3, ushort c4);

    static bool isIdentLetter(ushort c);

    static bool isDecimalDigit(ushort c);

    inline int ival() const { return qsyylval.ival; }

    inline double dval() const { return qsyylval.dval; }

    inline QScriptNameIdImpl *ustr() const { return qsyylval.ustr; }

    const QChar *characterBuffer() const { return buffer16; }

    int characterCount() const { return pos16; }

private:

    void record8(ushort c);

    void record16(QChar c);

    void recordStartPos();

    int findReservedWord(const QChar *buffer, int size) const;

    void syncProhibitAutomaticSemicolon();

    const QChar *code;

    uint length;

    int yycolumn;

    int startlineno;

    int startcolumn;

    int bol;     // begin of line

    union {

        int ival;

        double dval;

        QScriptNameIdImpl *ustr;

    } qsyylval;

    // current and following unicode characters

    ushort current, next1, next2, next3;

    struct keyword {

        const char *name;

        int token;

    };

    QString errmsg;

    Error err;

    bool wantRx;

    bool check_reserved;

    ParenthesesState parenthesesState;

    int parenthesesCount;

    bool prohibitAutomaticSemicolon;

};

} // namespace QScript

QT_END_NAMESPACE

#endif