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#include "qdeclarativecontext.h"

#include "private/qdeclarativecontext_p.h"

#include "private/qdeclarativecomponent_p.h"

#include "private/qdeclarativeexpression_p.h"

#include "private/qdeclarativeengine_p.h"

#include "qdeclarativeengine.h"

#include "private/qdeclarativecompiledbindings_p.h"

#include "qdeclarativeinfo.h"

#include "private/qdeclarativeglobalscriptclass_p.h"

#include <qscriptengine.h>

#include <QtCore/qvarlengtharray.h>

#include <QtCore/qdebug.h>

#include <private/qscriptdeclarativeclass_p.h>

QT_BEGIN_NAMESPACE

QDeclarativeContextPrivate::QDeclarativeContextPrivate()

: data(0), notifyIndex(-1)

{

}

/*!

    \class QDeclarativeContext

    \since 4.7

    \brief The QDeclarativeContext class defines a context within a QML engine.

    \mainclass

    Contexts allow data to be exposed to the QML components instantiated by the

    QML engine.

    Each QDeclarativeContext contains a set of properties, distinct from its QObject 

    properties, that allow data to be explicitly bound to a context by name.  The 

    context properties are defined and updated by calling 

    QDeclarativeContext::setContextProperty().  The following example shows a Qt model 

    being bound to a context and then accessed from a QML file.

    \code

    QDeclarativeEngine engine;

    QDeclarativeContext *context = new QDeclarativeContext(engine.rootContext());

    context->setContextProperty("myModel", modelData);

    QDeclarativeComponent component(&engine, "ListView { model=myModel }");

    component.create(context);

    \endcode

    To simplify binding and maintaining larger data sets, a context object can be set

    on a QDeclarativeContext.  All the properties of the context object are available

    by name in the context, as though they were all individually added through calls

    to QDeclarativeContext::setContextProperty().  Changes to the property's values are 

    detected through the property's notify signal.  Setting a context object is both 

    faster and easier than manually adding and maintaing context property values.

    The following example has the same effect as the previous one, but it uses a context

    object.

    \code

    class MyDataSet : ... {

        ...

        Q_PROPERTY(QAbstractItemModel *myModel READ model NOTIFY modelChanged)

        ...

    };

    MyDataSet *myDataSet = new MyDataSet;

    QDeclarativeEngine engine;

    QDeclarativeContext *context = new QDeclarativeContext(engine.rootContext());

    context->setContextObject(myDataSet);

    QDeclarativeComponent component(&engine, "ListView { model=myModel }");

    component.create(context);

    \endcode

    All properties added explicitly by QDeclarativeContext::setContextProperty() take 

    precedence over the context object's properties.

    Contexts form a hierarchy.  The root of this heirarchy is the QDeclarativeEngine's

    \l {QDeclarativeEngine::rootContext()}{root context}.  A component instance can 

    access the data in its own context, as well as all its ancestor contexts.  Data

    can be made available to all instances by modifying the 

    \l {QDeclarativeEngine::rootContext()}{root context}.

    The following example defines two contexts - \c context1 and \c context2.  The

    second context overrides the "b" context property inherited from the first with a

    new value.

    \code

    QDeclarativeEngine engine;

    QDeclarativeContext *context1 = new QDeclarativeContext(engine.rootContext());

    QDeclarativeContext *context2 = new QDeclarativeContext(context1);

    context1->setContextProperty("a", 12);

    context1->setContextProperty("b", 12);

    context2->setContextProperty("b", 15);

    \endcode

    While QML objects instantiated in a context are not strictly owned by that 

    context, their bindings are.  If a context is destroyed, the property bindings of 

    outstanding QML objects will stop evaluating.

    \note Setting the context object or adding new context properties after an object

    has been created in that context is an expensive operation (essentially forcing all bindings

    to reevaluate). Thus whenever possible you should complete "setup" of the context

    before using it to create any objects.

*/

/*! \internal */

QDeclarativeContext::QDeclarativeContext(QDeclarativeEngine *e, bool)

: QObject(*(new QDeclarativeContextPrivate))

{

    Q_D(QDeclarativeContext);

    d->data = new QDeclarativeContextData(this);

    d->data->engine = e;

}

/*!

    Create a new QDeclarativeContext as a child of \a engine's root context, and the

    QObject \a parent.

*/

QDeclarativeContext::QDeclarativeContext(QDeclarativeEngine *engine, QObject *parent)

: QObject(*(new QDeclarativeContextPrivate), parent)

{

    Q_D(QDeclarativeContext);

    d->data = new QDeclarativeContextData(this);

    d->data->setParent(engine?QDeclarativeContextData::get(engine->rootContext()):0);

}

/*!

    Create a new QDeclarativeContext with the given \a parentContext, and the

    QObject \a parent.

*/

QDeclarativeContext::QDeclarativeContext(QDeclarativeContext *parentContext, QObject *parent)

: QObject(*(new QDeclarativeContextPrivate), parent)

{

    Q_D(QDeclarativeContext);

    d->data = new QDeclarativeContextData(this);

    d->data->setParent(parentContext?QDeclarativeContextData::get(parentContext):0);

}

/*!

    \internal

*/

QDeclarativeContext::QDeclarativeContext(QDeclarativeContextData *data)

: QObject(*(new QDeclarativeContextPrivate), 0)

{

    Q_D(QDeclarativeContext);

    d->data = data;

}

/*!

    Destroys the QDeclarativeContext.

    Any expressions, or sub-contexts dependent on this context will be

    invalidated, but not destroyed (unless they are parented to the QDeclarativeContext

    object).

 */

QDeclarativeContext::~QDeclarativeContext()

{

    Q_D(QDeclarativeContext);

    if (!d->data->isInternal)

        d->data->destroy();

}

/*!

    Returns whether the context is valid.

    To be valid, a context must have a engine, and it's contextObject(), if any, 

    must not have been deleted.

*/

bool QDeclarativeContext::isValid() const

{

    Q_D(const QDeclarativeContext);

    return d->data && d->data->isValid();

}

/*!

    Return the context's QDeclarativeEngine, or 0 if the context has no QDeclarativeEngine or the

    QDeclarativeEngine was destroyed.

*/

QDeclarativeEngine *QDeclarativeContext::engine() const

{

    Q_D(const QDeclarativeContext);

    return d->data->engine;

}

/*!

    Return the context's parent QDeclarativeContext, or 0 if this context has no

    parent or if the parent has been destroyed.

*/

QDeclarativeContext *QDeclarativeContext::parentContext() const

{

    Q_D(const QDeclarativeContext);

    return d->data->parent?d->data->parent->asQDeclarativeContext():0;

}

/*!

    Return the context object, or 0 if there is no context object.

*/

QObject *QDeclarativeContext::contextObject() const

{

    Q_D(const QDeclarativeContext);

    return d->data->contextObject;

}

/*!

    Set the context \a object.

*/

void QDeclarativeContext::setContextObject(QObject *object)

{

    Q_D(QDeclarativeContext);

    QDeclarativeContextData *data = d->data;

    if (data->isInternal) {

        qWarning("QDeclarativeContext: Cannot set context object for internal context.");

        return;

    }

    if (!isValid()) {

        qWarning("QDeclarativeContext: Cannot set context object on invalid context.");

        return;

    }

    data->contextObject = object;

}

/*!

    Set a the \a value of the \a name property on this context.

*/

void QDeclarativeContext::setContextProperty(const QString &name, const QVariant &value)

{

    Q_D(QDeclarativeContext);

    if (d->notifyIndex == -1)

        d->notifyIndex = this->metaObject()->methodCount();

    QDeclarativeContextData *data = d->data;

    if (data->isInternal) {

        qWarning("QDeclarativeContext: Cannot set property on internal context.");

        return;

    }

    if (!isValid()) {

        qWarning("QDeclarativeContext: Cannot set property on invalid context.");

        return;

    }

    if (data->engine) {

        bool ok;

        QObject *o = QDeclarativeEnginePrivate::get(data->engine)->toQObject(value, &ok);

        if (ok) {

            setContextProperty(name, o);

            return;

        }

    }

    if (!data->propertyNames) data->propertyNames = new QDeclarativeIntegerCache(data->engine);

    int idx = data->propertyNames->value(name);

    if (idx == -1) {

        data->propertyNames->add(name, data->idValueCount + d->propertyValues.count());

        d->propertyValues.append(value);

        data->refreshExpressions();

    } else {

        d->propertyValues[idx] = value;

        QMetaObject::activate(this, idx + d->notifyIndex, 0);

    }

}

/*!

    Set the \a value of the \a name property on this context.

    QDeclarativeContext does \bold not take ownership of \a value.

*/

void QDeclarativeContext::setContextProperty(const QString &name, QObject *value)

{

    Q_D(QDeclarativeContext);

    if (d->notifyIndex == -1)

        d->notifyIndex = this->metaObject()->methodCount();

    QDeclarativeContextData *data = d->data;

    if (data->isInternal) {

        qWarning("QDeclarativeContext: Cannot set property on internal context.");

        return;

    }

    if (!isValid()) {

        qWarning("QDeclarativeContext: Cannot set property on invalid context.");

        return;

    }

    if (!data->propertyNames) data->propertyNames = new QDeclarativeIntegerCache(data->engine);

    int idx = data->propertyNames->value(name);

    if (idx == -1) {

        data->propertyNames->add(name, data->idValueCount + d->propertyValues.count());

        d->propertyValues.append(QVariant::fromValue(value));

        data->refreshExpressions();

    } else {

        d->propertyValues[idx] = QVariant::fromValue(value);

        QMetaObject::activate(this, idx + d->notifyIndex, 0);

    }

}

/*!

  Returns the value of the \a name property for this context

  as a QVariant.

 */

QVariant QDeclarativeContext::contextProperty(const QString &name) const

{

    Q_D(const QDeclarativeContext);

    QVariant value;

    int idx = -1;

    QDeclarativeContextData *data = d->data;

    if (data->propertyNames)

        idx = data->propertyNames->value(name);

    if (idx == -1) {

        QByteArray utf8Name = name.toUtf8();

        if (data->contextObject) {

            QObject *obj = data->contextObject;

            QDeclarativePropertyCache::Data local;

            QDeclarativePropertyCache::Data *property = 

                QDeclarativePropertyCache::property(data->engine, obj, name, local);

            if (property) value = obj->metaObject()->property(property->coreIndex).read(obj);

        }

        if (!value.isValid() && parentContext())

            value = parentContext()->contextProperty(name);

    } else {

        if (idx >= d->propertyValues.count())

            value = QVariant::fromValue(data->idValues[idx - d->propertyValues.count()].data());

        else

            value = d->propertyValues[idx];

    }

    return value;

}

/*!

    Resolves the URL \a src relative to the URL of the

    containing component.

    \sa QDeclarativeEngine::baseUrl(), setBaseUrl()

*/

QUrl QDeclarativeContext::resolvedUrl(const QUrl &src)

{

    Q_D(QDeclarativeContext);

    return d->data->resolvedUrl(src);

}

QUrl QDeclarativeContextData::resolvedUrl(const QUrl &src)

{

    QDeclarativeContextData *ctxt = this;

    if (src.isRelative() && !src.isEmpty()) {

        if (ctxt) {

            while(ctxt) {

                if(ctxt->url.isValid())

                    break;

                else

                    ctxt = ctxt->parent;

            }

            if (ctxt)

                return ctxt->url.resolved(src);

            else if (engine)

                return engine->baseUrl().resolved(src);

        }

        return QUrl();

    } else {

        return src;

    }

}

/*!

    Explicitly sets the url resolvedUrl() will use for relative references to \a baseUrl.

    Calling this function will override the url of the containing

    component used by default.

    \sa resolvedUrl()

*/

void QDeclarativeContext::setBaseUrl(const QUrl &baseUrl)

{

    Q_D(QDeclarativeContext);

    d->data->url = baseUrl;

}

/*!

    Returns the base url of the component, or the containing component

    if none is set.

*/

QUrl QDeclarativeContext::baseUrl() const

{

    Q_D(const QDeclarativeContext);

    const QDeclarativeContextData* data = d->data;

    while (data && data->url.isEmpty()) 

        data = data->parent;

    if (data)

        return data->url;

    else

        return QUrl();

}

int QDeclarativeContextPrivate::context_count(QDeclarativeListProperty<QObject> *prop)

{

    QDeclarativeContext *context = static_cast<QDeclarativeContext*>(prop->object);

    QDeclarativeContextPrivate *d = QDeclarativeContextPrivate::get(context);

    int contextProperty = (int)(intptr_t)prop->data;

    if (d->propertyValues.at(contextProperty).userType() != qMetaTypeId<QList<QObject*> >()) {

        return 0;

    } else {

        return ((const QList<QObject> *)d->propertyValues.at(contextProperty).constData())->count();

    }

}

QObject *QDeclarativeContextPrivate::context_at(QDeclarativeListProperty<QObject> *prop, int index)

{

    QDeclarativeContext *context = static_cast<QDeclarativeContext*>(prop->object);

    QDeclarativeContextPrivate *d = QDeclarativeContextPrivate::get(context);

    int contextProperty = (int)(intptr_t)prop->data;

    if (d->propertyValues.at(contextProperty).userType() != qMetaTypeId<QList<QObject*> >()) {

        return 0;

    } else {

        return ((const QList<QObject*> *)d->propertyValues.at(contextProperty).constData())->at(index);

    }

}

QDeclarativeContextData::QDeclarativeContextData()

: parent(0), engine(0), isInternal(false), publicContext(0), propertyNames(0), contextObject(0),

  imports(0), childContexts(0), nextChild(0), prevChild(0), expressions(0), contextObjects(0),

  contextGuards(0), idValues(0), idValueCount(0), optimizedBindings(0), linkedContext(0),

  componentAttached(0)

{

}

QDeclarativeContextData::QDeclarativeContextData(QDeclarativeContext *ctxt)

: parent(0), engine(0), isInternal(false), publicContext(ctxt), propertyNames(0), contextObject(0),

  imports(0), childContexts(0), nextChild(0), prevChild(0), expressions(0), contextObjects(0),

  contextGuards(0), idValues(0), idValueCount(0), optimizedBindings(0), linkedContext(0),

  componentAttached(0)

{

}

void QDeclarativeContextData::invalidate()

{

    while (childContexts) 

        childContexts->invalidate();

    while (componentAttached) {

        QDeclarativeComponentAttached *a = componentAttached;

        componentAttached = a->next;

        if (componentAttached) componentAttached->prev = &componentAttached;

        a->next = 0;

        a->prev = 0;

        emit a->destruction();

    }

    if (prevChild) {

        *prevChild = nextChild;

        if (nextChild) nextChild->prevChild = prevChild;

        nextChild = 0;

        prevChild = 0;

    }

    engine = 0;

    parent = 0;