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#include "private/qdeclarativepropertychanges_p.h"

#include "private/qdeclarativeopenmetaobject_p.h"

#include <qdeclarativeinfo.h>

#include <qdeclarativecustomparser_p.h>

#include <qdeclarativeparser_p.h>

#include <qdeclarativeexpression.h>

#include <qdeclarativebinding_p.h>

#include <qdeclarativecontext.h>

#include <qdeclarativeguard_p.h>

#include <qdeclarativeproperty_p.h>

#include <qdeclarativecontext_p.h>

#include <QtCore/qdebug.h>

#include <private/qobject_p.h>

QT_BEGIN_NAMESPACE

/*!

    \qmlclass PropertyChanges QDeclarativePropertyChanges

    \since 4.7

    \brief The PropertyChanges element describes new property values for a state.

    PropertyChanges provides a state change that modifies the properties of an item.

    Here is a property change that modifies the text and color of a Text element

    when it is clicked:

    \qml

    Text {

        id: myText

        width: 100; height: 100

        text: "Hello"

        color: "blue"

        states: State {

            name: "myState"

            PropertyChanges {

                target: myText

                text: "Goodbye"

                color: "red"

            }

        }

        MouseArea { anchors.fill: parent; onClicked: myText.state = 'myState' }

    }

    \endqml

    State-specific script for signal handlers can also be specified:

    \qml

    PropertyChanges {

        target: myMouseArea

        onClicked: doSomethingDifferent()

    }

    \endqml

    You can reset a property in a state change by assigning \c undefined. In the following

    example we reset \c theText's width when we enter state1. This will give the text its

    natural width (which is the whole string on one line).

    \qml

    import Qt 4.7

    Rectangle {

        width: 640

        height: 480

        Text {

            id: theText

            width: 50

            wrapMode: Text.WordWrap

            text: "a text string that is longer than 50 pixels"

        }

        states: State {

            name: "state1"

            PropertyChanges {

                target: theText

                width: undefined

            }

        }

    }

    \endqml

    Anchor margins should be changed with PropertyChanges, but other anchor changes or changes to

    an Item's parent should be done using the associated change elements

    (ParentChange and AnchorChanges, respectively).

    \sa {qmlstate}{States}, QtDeclarative

*/

/*!

    \internal

    \class QDeclarativePropertyChanges

    \brief The QDeclarativePropertyChanges class describes new property values for a state.

*/

/*!

    \qmlproperty Object PropertyChanges::target

    This property holds the object which contains the properties to be changed.

*/

class QDeclarativeReplaceSignalHandler : public QDeclarativeActionEvent

{

public:

    QDeclarativeReplaceSignalHandler() : expression(0), reverseExpression(0),

                                rewindExpression(0), ownedExpression(0) {}

    ~QDeclarativeReplaceSignalHandler() {

        delete ownedExpression;

    }

    virtual QString typeName() const { return QLatin1String("ReplaceSignalHandler"); }

    QDeclarativeProperty property;

    QDeclarativeExpression *expression;

    QDeclarativeExpression *reverseExpression;

    QDeclarativeExpression *rewindExpression;

    QDeclarativeGuard<QDeclarativeExpression> ownedExpression;

    virtual void execute(Reason) {

        ownedExpression = QDeclarativePropertyPrivate::setSignalExpression(property, expression);

        if (ownedExpression == expression)

            ownedExpression = 0;

    }

    virtual bool isReversable() { return true; }

    virtual void reverse(Reason) {

        ownedExpression = QDeclarativePropertyPrivate::setSignalExpression(property, reverseExpression);

        if (ownedExpression == reverseExpression)

            ownedExpression = 0;

    }

    virtual void saveOriginals() {

        saveCurrentValues();

        reverseExpression = rewindExpression;

    }

    /*virtual void copyOriginals(QDeclarativeActionEvent *other)

    {

        QDeclarativeReplaceSignalHandler *rsh = static_cast<QDeclarativeReplaceSignalHandler*>(other);

        saveCurrentValues();

        if (rsh == this)

            return;

        reverseExpression = rsh->reverseExpression;

        if (rsh->ownedExpression == reverseExpression) {

            ownedExpression = rsh->ownedExpression;

            rsh->ownedExpression = 0;

        }

    }*/

    virtual void rewind() {

        ownedExpression = QDeclarativePropertyPrivate::setSignalExpression(property, rewindExpression);

        if (ownedExpression == rewindExpression)

            ownedExpression = 0;

    }

    virtual void saveCurrentValues() { 

        rewindExpression = QDeclarativePropertyPrivate::signalExpression(property);

    }

    virtual bool override(QDeclarativeActionEvent*other) {

        if (other == this)

            return true;

        if (other->typeName() != typeName())

            return false;

        if (static_cast<QDeclarativeReplaceSignalHandler*>(other)->property == property)

            return true;

        return false;

    }

};

class QDeclarativePropertyChangesPrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QDeclarativePropertyChanges)

public:

    QDeclarativePropertyChangesPrivate() : object(0), decoded(true), restore(true),

                                isExplicit(false) {}

    QObject *object;

    QByteArray data;

    bool decoded : 1;

    bool restore : 1;

    bool isExplicit : 1;

    void decode();

    QList<QPair<QByteArray, QVariant> > properties;

    QList<QPair<QByteArray, QDeclarativeExpression *> > expressions;

    QList<QDeclarativeReplaceSignalHandler*> signalReplacements;

    QDeclarativeProperty property(const QByteArray &);

};

void

QDeclarativePropertyChangesParser::compileList(QList<QPair<QByteArray, QVariant> > &list,

                                     const QByteArray &pre,

                                     const QDeclarativeCustomParserProperty &prop)

{

    QByteArray propName = pre + prop.name();

    QList<QVariant> values = prop.assignedValues();

    for (int ii = 0; ii < values.count(); ++ii) {

        const QVariant &value = values.at(ii);

        if (value.userType() == qMetaTypeId<QDeclarativeCustomParserNode>()) {

            error(qvariant_cast<QDeclarativeCustomParserNode>(value),

                  QDeclarativePropertyChanges::tr("PropertyChanges does not support creating state-specific objects."));

            continue;

        } else if(value.userType() == qMetaTypeId<QDeclarativeCustomParserProperty>()) {

            QDeclarativeCustomParserProperty prop =

                qvariant_cast<QDeclarativeCustomParserProperty>(value);

            QByteArray pre = propName + '.';

            compileList(list, pre, prop);

        } else {

            list << qMakePair(propName, value);

        }

    }

}

QByteArray

QDeclarativePropertyChangesParser::compile(const QList<QDeclarativeCustomParserProperty> &props)

{

    QList<QPair<QByteArray, QVariant> > data;

    for(int ii = 0; ii < props.count(); ++ii)

        compileList(data, QByteArray(), props.at(ii));

    QByteArray rv;

    QDataStream ds(&rv, QIODevice::WriteOnly);

    ds << data.count();

    for(int ii = 0; ii < data.count(); ++ii) {

        QDeclarativeParser::Variant v = qvariant_cast<QDeclarativeParser::Variant>(data.at(ii).second);

        QVariant var;

        bool isScript = v.isScript();

        switch(v.type()) {

        case QDeclarativeParser::Variant::Boolean:

            var = QVariant(v.asBoolean());

            break;

        case QDeclarativeParser::Variant::Number:

            var = QVariant(v.asNumber());

            break;

        case QDeclarativeParser::Variant::String:

            var = QVariant(v.asString());

            break;

        case QDeclarativeParser::Variant::Invalid:

        case QDeclarativeParser::Variant::Script:

            var = QVariant(v.asScript());

            break;

        }

        ds << data.at(ii).first << isScript << var;

    }

    return rv;

}

void QDeclarativePropertyChangesPrivate::decode()

{

    Q_Q(QDeclarativePropertyChanges);

    if (decoded)

        return;

    QDataStream ds(&data, QIODevice::ReadOnly);

    int count;

    ds >> count;

    for (int ii = 0; ii < count; ++ii) {

        QByteArray name;

        bool isScript;

        QVariant data;

        ds >> name;

        ds >> isScript;

        ds >> data;

        QDeclarativeProperty prop = property(name);      //### better way to check for signal property?

        if (prop.type() & QDeclarativeProperty::SignalProperty) {

            QDeclarativeExpression *expression = new QDeclarativeExpression(qmlContext(q), object, data.toString());

            QDeclarativeData *ddata = QDeclarativeData::get(q);

            if (ddata && ddata->outerContext && !ddata->outerContext->url.isEmpty())

                expression->setSourceLocation(ddata->outerContext->url.toString(), ddata->lineNumber);

            QDeclarativeReplaceSignalHandler *handler = new QDeclarativeReplaceSignalHandler;

            handler->property = prop;

            handler->expression = expression;

            signalReplacements << handler;

        } else if (isScript) {

            QDeclarativeExpression *expression = new QDeclarativeExpression(qmlContext(q), object, data.toString());

            QDeclarativeData *ddata = QDeclarativeData::get(q);

            if (ddata && ddata->outerContext && !ddata->outerContext->url.isEmpty())

                expression->setSourceLocation(ddata->outerContext->url.toString(), ddata->lineNumber);

            expressions << qMakePair(name, expression);

        } else {

            properties << qMakePair(name, data);

        }

    }

    decoded = true;

    data.clear();

}

void QDeclarativePropertyChangesParser::setCustomData(QObject *object,

                                            const QByteArray &data)

{

    QDeclarativePropertyChangesPrivate *p =

        static_cast<QDeclarativePropertyChangesPrivate *>(QObjectPrivate::get(object));

    p->data = data;

    p->decoded = false;

}

QDeclarativePropertyChanges::QDeclarativePropertyChanges()

: QDeclarativeStateOperation(*(new QDeclarativePropertyChangesPrivate))

{

}

QDeclarativePropertyChanges::~QDeclarativePropertyChanges()

{

    Q_D(QDeclarativePropertyChanges);

    for(int ii = 0; ii < d->expressions.count(); ++ii)

        delete d->expressions.at(ii).second;

    for(int ii = 0; ii < d->signalReplacements.count(); ++ii)

        delete d->signalReplacements.at(ii);

}

QObject *QDeclarativePropertyChanges::object() const

{

    Q_D(const QDeclarativePropertyChanges);

    return d->object;

}

void QDeclarativePropertyChanges::setObject(QObject *o)

{

    Q_D(QDeclarativePropertyChanges);

    d->object = o;

}

/*!

    \qmlproperty bool PropertyChanges::restoreEntryValues

    Whether or not the previous values should be restored when

    leaving the state. By default, restoreEntryValues is true.

    By setting restoreEntryValues to false, you can create a temporary state

    that has permanent effects on property values.

*/

bool QDeclarativePropertyChanges::restoreEntryValues() const

{

    Q_D(const QDeclarativePropertyChanges);

    return d->restore;

}

void QDeclarativePropertyChanges::setRestoreEntryValues(bool v)

{

    Q_D(QDeclarativePropertyChanges);

    d->restore = v;

}

QDeclarativeProperty

QDeclarativePropertyChangesPrivate::property(const QByteArray &property)

{

    Q_Q(QDeclarativePropertyChanges);

    QDeclarativeProperty prop(object, QString::fromUtf8(property), qmlContext(q));

    if (!prop.isValid()) {

        qmlInfo(q) << QDeclarativePropertyChanges::tr("Cannot assign to non-existent property \"%1\"").arg(QString::fromUtf8(property));

        return QDeclarativeProperty();

    } else if (!(prop.type() & QDeclarativeProperty::SignalProperty) && !prop.isWritable()) {

        qmlInfo(q) << QDeclarativePropertyChanges::tr("Cannot assign to read-only property \"%1\"").arg(QString::fromUtf8(property));

        return QDeclarativeProperty();

    }

    return prop;

}

QDeclarativePropertyChanges::ActionList QDeclarativePropertyChanges::actions()

{

    Q_D(QDeclarativePropertyChanges);

    d->decode();

    ActionList list;

    for (int ii = 0; ii < d->properties.count(); ++ii) {

        QByteArray property = d->properties.at(ii).first;

        QDeclarativeAction a(d->object, QString::fromUtf8(property),

                 qmlContext(this), d->properties.at(ii).second);

        if (a.property.isValid()) {

            a.restore = restoreEntryValues();

            list << a;

        }

    }

    for (int ii = 0; ii < d->signalReplacements.count(); ++ii) {

        QDeclarativeReplaceSignalHandler *handler = d->signalReplacements.at(ii);

        if (handler->property.isValid()) {

            QDeclarativeAction a;

            a.event = handler;

            list << a;

        }

    }

    for (int ii = 0; ii < d->expressions.count(); ++ii) {

        QByteArray property = d->expressions.at(ii).first;

        QDeclarativeProperty prop = d->property(property);

        if (prop.isValid()) {

            QDeclarativeAction a;

            a.restore = restoreEntryValues();

            a.property = prop;

            a.fromValue = a.property.read();

            a.specifiedObject = d->object;

            a.specifiedProperty = QString::fromUtf8(property);

            if (d->isExplicit) {

                a.toValue = d->expressions.at(ii).second->evaluate();

            } else {

                QDeclarativeExpression *e = d->expressions.at(ii).second;

                QDeclarativeBinding *newBinding = 

                    new QDeclarativeBinding(e->expression(), object(), qmlContext(this));

                newBinding->setTarget(prop);

                newBinding->setSourceLocation(e->sourceFile(), e->lineNumber());

                a.toBinding = newBinding;

                a.deletableToBinding = true;

            }

            list << a;

        }

    }

    return list;

}

/*!

    \qmlproperty bool PropertyChanges::explicit

    If explicit is set to true, any potential bindings will be interpreted as

    once-off assignments that occur when the state is entered.

    In the following example, the addition of explicit prevents myItem.width from

    being bound to parent.width. Instead, it is assigned the value of parent.width

    at the time of the state change.

    \qml

    PropertyChanges {

        target: myItem

        explicit: true

        width: parent.width

    }

    \endqml

    By default, explicit is false.

*/

bool QDeclarativePropertyChanges::isExplicit() const

{

    Q_D(const QDeclarativePropertyChanges);

    return d->isExplicit;

}

void QDeclarativePropertyChanges::setIsExplicit(bool e)

{

    Q_D(QDeclarativePropertyChanges);

    d->isExplicit = e;

}

QT_END_NAMESPACE