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

**

** 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.

** $QT_END_LICENSE$

**

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

#include "config.h" // compile on Windows

#include "qscriptstring.h"

#include "qscriptstring_p.h"

#include "qscriptengine.h"

#include "qscriptengine_p.h"

QT_BEGIN_NAMESPACE

/*!

  \since 4.4

  \class QScriptString

  \brief The QScriptString class acts as a handle to "interned" strings in a QScriptEngine.

  \ingroup script

  QScriptString can be used to achieve faster (repeated)

  property getting/setting, and comparison of property names, of

  script objects.

  To get a QScriptString representation of a string, pass the string

  to QScriptEngine::toStringHandle(). The typical usage pattern is to

  register one or more pre-defined strings when setting up your script

  environment, then subsequently use the relevant QScriptString as

  argument to e.g. QScriptValue::property().

  Call the toString() function to obtain the string that a

  QScriptString represents.

  Call the toArrayIndex() function to convert a QScriptString to an

  array index. This is useful when using QScriptClass to implement

  array-like objects.

*/

/*!

  Constructs an invalid QScriptString.

*/

QScriptString::QScriptString()

    : d_ptr(0)

{

}

/*!

  Constructs a new QScriptString that is a copy of \a other.

*/

QScriptString::QScriptString(const QScriptString &other)

    : d_ptr(other.d_ptr)

{

    if (d_func() && (d_func()->type == QScriptStringPrivate::StackAllocated)) {

        Q_ASSERT(d_func()->ref != 1);

        d_ptr.detach();

        d_func()->ref = 1;

        d_func()->type = QScriptStringPrivate::HeapAllocated;

        d_func()->engine->registerScriptString(d_func());

    }

}

/*!

  Destroys this QScriptString.

*/

QScriptString::~QScriptString()

{

    Q_D(QScriptString);

    if (d) {

        switch (d->type) {

        case QScriptStringPrivate::StackAllocated:

            Q_ASSERT(d->ref == 1);

            d->ref.ref(); // avoid deletion

            break;

        case QScriptStringPrivate::HeapAllocated:

            if (d->engine && (d->ref == 1))

                d->engine->unregisterScriptString(d);

            break;

        }

    }

}

/*!

  Assigns the \a other value to this QScriptString.

*/

QScriptString &QScriptString::operator=(const QScriptString &other)

{

    if (d_func() && d_func()->engine && (d_func()->ref == 1) && (d_func()->type == QScriptStringPrivate::HeapAllocated)) {

        // current d_ptr will be deleted at the assignment below, so unregister it first

        d_func()->engine->unregisterScriptString(d_func());

    }

    d_ptr = other.d_ptr;

    if (d_func() && (d_func()->type == QScriptStringPrivate::StackAllocated)) {

        Q_ASSERT(d_func()->ref != 1);

        d_ptr.detach();

        d_func()->ref = 1;

        d_func()->type = QScriptStringPrivate::HeapAllocated;

        d_func()->engine->registerScriptString(d_func());

    }

    return *this;

}

/*!

  Returns true if this QScriptString is valid; otherwise

  returns false.

*/

bool QScriptString::isValid() const

{

    return QScriptStringPrivate::isValid(*this);

}

/*!

  Returns true if this QScriptString is equal to \a other;

  otherwise returns false.

*/

bool QScriptString::operator==(const QScriptString &other) const

{

    Q_D(const QScriptString);

    if (!d || !other.d_func())

        return d == other.d_func();

    return d->identifier == other.d_func()->identifier;

}

/*!

  Returns true if this QScriptString is not equal to \a other;

  otherwise returns false.

*/

bool QScriptString::operator!=(const QScriptString &other) const

{

    return !operator==(other);

}

/*!

  \since 4.6

  Attempts to convert this QScriptString to a QtScript array index,

  and returns the result.

  If a conversion error occurs, *\a{ok} is set to false; otherwise

  *\a{ok} is set to true.

*/

quint32 QScriptString::toArrayIndex(bool *ok) const

{

    Q_D(const QScriptString);

    if (!d) {

        if (ok)

            *ok = false;

        return -1;

    }

    bool tmp;

    bool *okok = ok ? ok : &tmp;

    quint32 result = d->identifier.toArrayIndex(okok);

    if (!*okok)

        result = -1;

    return result;

}

/*!

  Returns the string that this QScriptString represents, or a

  null string if this QScriptString is not valid.

  \sa isValid()

*/

QString QScriptString::toString() const

{

    Q_D(const QScriptString);

    if (!d || !d->engine)

        return QString();

    return d->identifier.ustring();

}

/*!

  Returns the string that this QScriptString represents, or a

  null string if this QScriptString is not valid.

  \sa toString()

*/

QScriptString::operator QString() const

{

    return toString();

}

uint qHash(const QScriptString &key)

{

    QScriptStringPrivate *d = QScriptStringPrivate::get(key);

    if (!d)

        return 0;

    return qHash(d->identifier.ustring().rep());

}

QT_END_NAMESPACE