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#include "private/qdeclarativeworkerscript_p.h"

#include "private/qdeclarativelistmodel_p.h"

#include "private/qdeclarativelistmodelworkeragent_p.h"

#include "private/qdeclarativeengine_p.h"

#include <QtCore/qcoreevent.h>

#include <QtCore/qcoreapplication.h>

#include <QtCore/qdebug.h>

#include <QtScript/qscriptengine.h>

#include <QtCore/qmutex.h>

#include <QtCore/qwaitcondition.h>

#include <QtScript/qscriptvalueiterator.h>

#include <QtCore/qfile.h>

#include <QtNetwork/qnetworkaccessmanager.h>

#include <QtDeclarative/qdeclarativeinfo.h>

#include "qdeclarativenetworkaccessmanagerfactory.h"

QT_BEGIN_NAMESPACE

class WorkerDataEvent : public QEvent

{

public:

    enum Type { WorkerData = QEvent::User };

    WorkerDataEvent(int workerId, const QVariant &data);

    virtual ~WorkerDataEvent();

    int workerId() const;

    QVariant data() const;

private:

    int m_id;

    QVariant m_data;

};

class WorkerLoadEvent : public QEvent

{

public:

    enum Type { WorkerLoad = WorkerDataEvent::WorkerData + 1 };

    WorkerLoadEvent(int workerId, const QUrl &url);

    int workerId() const;

    QUrl url() const;

private:

    int m_id;

    QUrl m_url;

};

class WorkerRemoveEvent : public QEvent

{

public:

    enum Type { WorkerRemove = WorkerLoadEvent::WorkerLoad + 1 };

    WorkerRemoveEvent(int workerId);

    int workerId() const;

private:

    int m_id;

};

class QDeclarativeWorkerScriptEnginePrivate : public QObject

{

    Q_OBJECT

public:

    enum WorkerEventTypes {

        WorkerDestroyEvent = QEvent::User + 100

    };

    QDeclarativeWorkerScriptEnginePrivate(QDeclarativeEngine *eng);

    struct ScriptEngine : public QDeclarativeScriptEngine

    {

        ScriptEngine(QDeclarativeWorkerScriptEnginePrivate *parent) : QDeclarativeScriptEngine(0), p(parent), accessManager(0) {}

        ~ScriptEngine() { delete accessManager; }

        QDeclarativeWorkerScriptEnginePrivate *p;

        QNetworkAccessManager *accessManager;

        virtual QNetworkAccessManager *networkAccessManager() {

            if (!accessManager) {

                if (p->qmlengine && p->qmlengine->networkAccessManagerFactory()) {

                    accessManager = p->qmlengine->networkAccessManagerFactory()->create(this);

                } else {

                    accessManager = new QNetworkAccessManager(this);

                }

            }

            return accessManager;

        }

    };

    ScriptEngine *workerEngine;

    static QDeclarativeWorkerScriptEnginePrivate *get(QScriptEngine *e) {

        return static_cast<ScriptEngine *>(e)->p;

    }

    QDeclarativeEngine *qmlengine;

    QMutex m_lock;

    QWaitCondition m_wait;

    struct WorkerScript {

        WorkerScript();

        int id;

        bool initialized;

        QDeclarativeWorkerScript *owner;

        QScriptValue object;

        QScriptValue callback;

    };

    QHash<int, WorkerScript *> workers;

    QScriptValue getWorker(int);

    int m_nextId;

    static QVariant scriptValueToVariant(const QScriptValue &);

    static QScriptValue variantToScriptValue(const QVariant &, QScriptEngine *);

    static QScriptValue onMessage(QScriptContext *ctxt, QScriptEngine *engine);

    static QScriptValue sendMessage(QScriptContext *ctxt, QScriptEngine *engine);

signals:

    void stopThread();

protected:

    virtual bool event(QEvent *);

private:

    void processMessage(int, const QVariant &);

    void processLoad(int, const QUrl &);

};

QDeclarativeWorkerScriptEnginePrivate::QDeclarativeWorkerScriptEnginePrivate(QDeclarativeEngine *engine)

: workerEngine(0), qmlengine(engine), m_nextId(0)

{

}

QScriptValue QDeclarativeWorkerScriptEnginePrivate::onMessage(QScriptContext *ctxt, QScriptEngine *engine)

{

    QDeclarativeWorkerScriptEnginePrivate *p = QDeclarativeWorkerScriptEnginePrivate::get(engine);

    int id = ctxt->thisObject().data().toVariant().toInt();

    WorkerScript *script = p->workers.value(id);

    if (!script)

        return engine->undefinedValue();

    if (ctxt->argumentCount() >= 1) 

        script->callback = ctxt->argument(0);

    return script->callback;

}

QScriptValue QDeclarativeWorkerScriptEnginePrivate::sendMessage(QScriptContext *ctxt, QScriptEngine *engine)

{

    if (!ctxt->argumentCount())

        return engine->undefinedValue();

    QDeclarativeWorkerScriptEnginePrivate *p = QDeclarativeWorkerScriptEnginePrivate::get(engine);

    int id = ctxt->thisObject().data().toVariant().toInt();

    WorkerScript *script = p->workers.value(id);

    if (!script)

        return engine->undefinedValue();

    QMutexLocker(&p->m_lock);

    if (script->owner)

        QCoreApplication::postEvent(script->owner,

                                    new WorkerDataEvent(0, scriptValueToVariant(ctxt->argument(0))));

    return engine->undefinedValue();

}

QScriptValue QDeclarativeWorkerScriptEnginePrivate::getWorker(int id)

{

    QHash<int, WorkerScript *>::ConstIterator iter = workers.find(id);

    if (iter == workers.end())

        return workerEngine->nullValue();

    WorkerScript *script = *iter;

    if (!script->initialized) {

        script->initialized = true;

        script->object = workerEngine->newObject();

        QScriptValue api = workerEngine->newObject();

        api.setData(script->id);

        api.setProperty(QLatin1String("onMessage"), workerEngine->newFunction(onMessage),

                        QScriptValue::PropertyGetter | QScriptValue::PropertySetter);

        api.setProperty(QLatin1String("sendMessage"), workerEngine->newFunction(sendMessage));

        script->object.setProperty(QLatin1String("WorkerScript"), api);

    }

    return script->object;

}

bool QDeclarativeWorkerScriptEnginePrivate::event(QEvent *event)

{

    if (event->type() == (QEvent::Type)WorkerDataEvent::WorkerData) {

        WorkerDataEvent *workerEvent = static_cast<WorkerDataEvent *>(event);

        processMessage(workerEvent->workerId(), workerEvent->data());

        return true;

    } else if (event->type() == (QEvent::Type)WorkerLoadEvent::WorkerLoad) {

        WorkerLoadEvent *workerEvent = static_cast<WorkerLoadEvent *>(event);

        processLoad(workerEvent->workerId(), workerEvent->url());

        return true;

    } else if (event->type() == (QEvent::Type)WorkerDestroyEvent) {

        emit stopThread();

        return true;

    } else {

        return QObject::event(event);

    }

}

void QDeclarativeWorkerScriptEnginePrivate::processMessage(int id, const QVariant &data)

{

    WorkerScript *script = workers.value(id);

    if (!script)

        return;

    if (script->callback.isFunction()) {

        QScriptValue args = workerEngine->newArray(1);

        args.setProperty(0, variantToScriptValue(data, workerEngine));

        script->callback.call(script->object, args);

    }

}

void QDeclarativeWorkerScriptEnginePrivate::processLoad(int id, const QUrl &url)

{

    if (url.isRelative())

        return;

    QString fileName = QDeclarativeEnginePrivate::urlToLocalFileOrQrc(url);

    QFile f(fileName);

    if (f.open(QIODevice::ReadOnly)) {

        QByteArray data = f.readAll();

        QString script = QString::fromUtf8(data);

        QScriptValue activation = getWorker(id);

        QScriptContext *ctxt = QScriptDeclarativeClass::pushCleanContext(workerEngine);

        QScriptValue urlContext = workerEngine->newObject();

        urlContext.setData(QScriptValue(workerEngine, fileName));

        ctxt->pushScope(urlContext);

        ctxt->pushScope(activation);

        ctxt->setActivationObject(activation);

        QDeclarativeScriptParser::extractPragmas(script);

        workerEngine->baseUrl = url;

        workerEngine->evaluate(script);

        workerEngine->popContext();

    } else {

        qWarning().nospace() << "WorkerScript: Cannot find source file " << url.toString();

    }

}

QVariant QDeclarativeWorkerScriptEnginePrivate::scriptValueToVariant(const QScriptValue &value)

{

    if (value.isBool()) {

        return QVariant(value.toBool());

    } else if (value.isString()) {

        return QVariant(value.toString());

    } else if (value.isNumber()) {

        return QVariant((qreal)value.toNumber());

    } else if (value.isArray()) {

        QVariantList list;

        quint32 length = (quint32)value.property(QLatin1String("length")).toNumber();

        for (quint32 ii = 0; ii < length; ++ii) {

            QVariant v = scriptValueToVariant(value.property(ii));

            list << v;

        }

        return QVariant(list);

    } else if (value.isQObject()) {

        QDeclarativeListModel *lm = qobject_cast<QDeclarativeListModel *>(value.toQObject());

        if (lm) {

            QDeclarativeListModelWorkerAgent *agent = lm->agent();

            if (agent) {

                QDeclarativeListModelWorkerAgent::VariantRef v(agent);

                return qVariantFromValue(v);

            } else {

                return QVariant();

            }

        } else {

            // No other QObject's are allowed to be sent

            return QVariant();

        }

    } else if (value.isObject()) {

        QVariantHash hash;

        QScriptValueIterator iter(value);

        while (iter.hasNext()) {

            iter.next();

            hash.insert(iter.name(), scriptValueToVariant(iter.value()));

        }

        return QVariant(hash);

    }

    return QVariant();

}

QScriptValue QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue(const QVariant &value, QScriptEngine *engine)

{

    if (value.userType() == QVariant::Bool) {

        return QScriptValue(value.toBool());

    } else if (value.userType() == QVariant::String) {

        return QScriptValue(value.toString());

    } else if (value.userType() == QMetaType::QReal) {

        return QScriptValue(value.toReal());

    } else if (value.userType() == qMetaTypeId<QDeclarativeListModelWorkerAgent::VariantRef>()) {

        QDeclarativeListModelWorkerAgent::VariantRef vr = qvariant_cast<QDeclarativeListModelWorkerAgent::VariantRef>(value);

        if (vr.a->scriptEngine() == 0)

            vr.a->setScriptEngine(engine);

        else if (vr.a->scriptEngine() != engine)

            return engine->nullValue();

        QScriptValue o = engine->newQObject(vr.a);

        o.setData(engine->newVariant(value)); // Keeps the agent ref so that it is cleaned up on gc

        return o;

    } else if (value.userType() == QMetaType::QVariantList) {

        QVariantList list = qvariant_cast<QVariantList>(value);

        QScriptValue rv = engine->newArray(list.count());

        for (quint32 ii = 0; ii < quint32(list.count()); ++ii)

            rv.setProperty(ii, variantToScriptValue(list.at(ii), engine));

        return rv;

    } else if (value.userType() == QMetaType::QVariantHash) {

        QVariantHash hash = qvariant_cast<QVariantHash>(value);

        QScriptValue rv = engine->newObject();

        for (QVariantHash::ConstIterator iter = hash.begin(); iter != hash.end(); ++iter)

            rv.setProperty(iter.key(), variantToScriptValue(iter.value(), engine));

        return rv;

    } else {

        return engine->nullValue();

    }

}

WorkerDataEvent::WorkerDataEvent(int workerId, const QVariant &data)

: QEvent((QEvent::Type)WorkerData), m_id(workerId), m_data(data)

{

}

WorkerDataEvent::~WorkerDataEvent()

{

}

int WorkerDataEvent::workerId() const

{

    return m_id;

}

QVariant WorkerDataEvent::data() const

{

    return m_data;

}

WorkerLoadEvent::WorkerLoadEvent(int workerId, const QUrl &url)

: QEvent((QEvent::Type)WorkerLoad), m_id(workerId), m_url(url)

{

}

int WorkerLoadEvent::workerId() const

{

    return m_id;

}

QUrl WorkerLoadEvent::url() const

{

    return m_url;

}

WorkerRemoveEvent::WorkerRemoveEvent(int workerId)

: QEvent((QEvent::Type)WorkerRemove), m_id(workerId)

{

}

int WorkerRemoveEvent::workerId() const

{

    return m_id;

}

QDeclarativeWorkerScriptEngine::QDeclarativeWorkerScriptEngine(QDeclarativeEngine *parent)

: QThread(parent), d(new QDeclarativeWorkerScriptEnginePrivate(parent))

{

    d->m_lock.lock();

    connect(d, SIGNAL(stopThread()), this, SLOT(quit()), Qt::DirectConnection);

    start(QThread::LowPriority);

    d->m_wait.wait(&d->m_lock);

    d->moveToThread(this);

    d->m_lock.unlock();

}

QDeclarativeWorkerScriptEngine::~QDeclarativeWorkerScriptEngine()

{

    d->m_lock.lock();

    qDeleteAll(d->workers);

    d->workers.clear();

    QCoreApplication::postEvent(d, new QEvent((QEvent::Type)QDeclarativeWorkerScriptEnginePrivate::WorkerDestroyEvent));

    d->m_lock.unlock();

    wait();

    d->deleteLater();

}

QDeclarativeWorkerScriptEnginePrivate::WorkerScript::WorkerScript()

: id(-1), initialized(false), owner(0)

{

}

int QDeclarativeWorkerScriptEngine::registerWorkerScript(QDeclarativeWorkerScript *owner)

{

    QDeclarativeWorkerScriptEnginePrivate::WorkerScript *script = new QDeclarativeWorkerScriptEnginePrivate::WorkerScript;

    script->id = d->m_nextId++;

    script->owner = owner;

    d->m_lock.lock();

    d->workers.insert(script->id, script);

    d->m_lock.unlock();

    return script->id;

}

void QDeclarativeWorkerScriptEngine::removeWorkerScript(int id)

{

    QCoreApplication::postEvent(d, new WorkerRemoveEvent(id));

}

void QDeclarativeWorkerScriptEngine::executeUrl(int id, const QUrl &url)

{

    QCoreApplication::postEvent(d, new WorkerLoadEvent(id, url));

}

void QDeclarativeWorkerScriptEngine::sendMessage(int id, const QVariant &data)

{

    QCoreApplication::postEvent(d, new WorkerDataEvent(id, data));

}

void QDeclarativeWorkerScriptEngine::run()

{

    d->m_lock.lock();

    d->workerEngine = new QDeclarativeWorkerScriptEnginePrivate::ScriptEngine(d);

    d->m_wait.wakeAll();

    d->m_lock.unlock();

    exec();

    delete d->workerEngine; d->workerEngine = 0;

}

/*!

    \qmlclass WorkerScript QDeclarativeWorkerScript

    \brief The WorkerScript element enables the use of threads in QML.

    Use WorkerScript to run operations in a new thread.

    This is useful for running operations in the background so

    that the main GUI thread is not blocked.

    Messages can be passed between the new thread and the parent thread

    using \l sendMessage() and the \l {WorkerScript::onMessage}{onMessage()} handler.

    An example: