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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 bindings or values for a state.

    property to \c true.

    \qml

    PropertyChanges {

        target: myMouseArea

        onClicked: doSomethingDifferent()

    }

    \endqml

    \sa {declarative/animation/states}{states example}, {qmlstate}{States}, QtDeclarative

*/

/*!

    \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

*/

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 \c myItem.width from

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