qdeclarativeworkerscript.cpp

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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 "private/qdeclarativeexpression_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 <QtCore/qdatetime.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 WorkerErrorEvent : public QEvent
{
public:
    enum Type { WorkerError = WorkerRemoveEvent::WorkerRemove + 1 };

    WorkerErrorEvent(const QDeclarativeError &error);

    QDeclarativeError error() const;

private:
    QDeclarativeError m_error;
};

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;
        QUrl source;
        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 &);
    void reportScriptException(WorkerScript *);
};

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);

        if (workerEngine->hasUncaughtException()) {
            reportScriptException(script);
            workerEngine->clearExceptions();
        }
    }
}

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 sourceCode = QString::fromUtf8(data);

        QScriptValue activation = getWorker(id);

        QScriptContext *ctxt = QScriptDeclarativeClass::pushCleanContext(workerEngine);
        QScriptValue urlContext = workerEngine->newObject();
        urlContext.setData(QScriptValue(workerEngine, url.toString()));
        ctxt->pushScope(urlContext);
        ctxt->pushScope(activation);
        ctxt->setActivationObject(activation);
        QDeclarativeScriptParser::extractPragmas(sourceCode);

        workerEngine->baseUrl = url;
        workerEngine->evaluate(sourceCode);

        WorkerScript *script = workers.value(id);
        if (script) {
            script->source = url;
            if (workerEngine->hasUncaughtException()) {
                reportScriptException(script);
                workerEngine->clearExceptions();
            }
        }

        workerEngine->popContext();
    } else {
        qWarning().nospace() << "WorkerScript: Cannot find source file " << url.toString();
    }
}

void QDeclarativeWorkerScriptEnginePrivate::reportScriptException(WorkerScript *script)
{
    if (!script || !workerEngine->hasUncaughtException())
        return;

    QDeclarativeError error;
    QDeclarativeExpressionPrivate::exceptionToError(workerEngine, error);
    error.setUrl(script->source);

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

    QMutexLocker(&p->m_lock);
    if (script->owner)
        QCoreApplication::postEvent(script->owner, new WorkerErrorEvent(error));
}

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.isDate()) {
        return QVariant(value.toDateTime());
#ifndef QT_NO_REGEXP
    } else if (value.isRegExp()) {
        return QVariant(value.toRegExp());
#endif
    } 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 QVariant::fromValue(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() == QVariant::DateTime) {
        return engine->newDate(value.toDateTime());
#ifndef QT_NO_REGEXP
    } else if (value.userType() == QVariant::RegExp) {
        return engine->newRegExp(value.toRegExp());
#endif
    } 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;
}

WorkerErrorEvent::WorkerErrorEvent(const QDeclarativeError &error)
: QEvent((QEvent::Type)WorkerError), m_error(error)
{
}

QDeclarativeError WorkerErrorEvent::error() const
{
    return m_error;
}

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::IdlePriority);
    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;
}


QDeclarativeWorkerScript::QDeclarativeWorkerScript(QObject *parent)
: QObject(parent), m_engine(0), m_scriptId(-1), m_componentComplete(true)
{
}

QDeclarativeWorkerScript::~QDeclarativeWorkerScript()
{
    if (m_scriptId != -1) m_engine->removeWorkerScript(m_scriptId);
}

QUrl QDeclarativeWorkerScript::source() const
{
    return m_source;
}

void QDeclarativeWorkerScript::setSource(const QUrl &source)
{
    if (m_source == source)
        return;

    m_source = source;

    if (engine())
        m_engine->executeUrl(m_scriptId, m_source);

    emit sourceChanged();
}

void QDeclarativeWorkerScript::sendMessage(const QScriptValue &message)
{
    if (!engine()) {
        qWarning("QDeclarativeWorkerScript: Attempt to send message before WorkerScript establishment");
        return;
    }

    m_engine->sendMessage(m_scriptId, QDeclarativeWorkerScriptEnginePrivate::scriptValueToVariant(message));
}

void QDeclarativeWorkerScript::classBegin()
{
    m_componentComplete = false;
}

QDeclarativeWorkerScriptEngine *QDeclarativeWorkerScript::engine()
{
    if (m_engine) return m_engine;
    if (m_componentComplete) {
        QDeclarativeEngine *engine = qmlEngine(this);
        if (!engine) {
            qWarning("QDeclarativeWorkerScript: engine() called without qmlEngine() set");
            return 0;
        }

        m_engine = QDeclarativeEnginePrivate::get(engine)->getWorkerScriptEngine();
        m_scriptId = m_engine->registerWorkerScript(this);

        if (m_source.isValid())
            m_engine->executeUrl(m_scriptId, m_source);

        return m_engine;
    }
    return 0;
}

void QDeclarativeWorkerScript::componentComplete()
{
    m_componentComplete = true;
    engine(); // Get it started now.
}

bool QDeclarativeWorkerScript::event(QEvent *event)
{
    if (event->type() == (QEvent::Type)WorkerDataEvent::WorkerData) {
        QDeclarativeEngine *engine = qmlEngine(this);
        if (engine) {
            QScriptEngine *scriptEngine = QDeclarativeEnginePrivate::getScriptEngine(engine);
            WorkerDataEvent *workerEvent = static_cast<WorkerDataEvent *>(event);
            QScriptValue value =
                QDeclarativeWorkerScriptEnginePrivate::variantToScriptValue(workerEvent->data(), scriptEngine);
            emit message(value);
        }
        return true;
    } else if (event->type() == (QEvent::Type)WorkerErrorEvent::WorkerError) {
        WorkerErrorEvent *workerEvent = static_cast<WorkerErrorEvent *>(event);
        QDeclarativeEnginePrivate::warning(qmlEngine(this), workerEvent->error());
        return true;
    } else {
        return QObject::event(event);
    }
}

QT_END_NAMESPACE

#include <qdeclarativeworkerscript.moc>