qdeclarativeboundsignal.cpp

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#include "private/qdeclarativeboundsignal_p.h"

#include "private/qmetaobjectbuilder_p.h"
#include "private/qdeclarativeengine_p.h"
#include "private/qdeclarativeexpression_p.h"
#include "private/qdeclarativecontext_p.h"
#include "private/qdeclarativemetatype_p.h"
#include "qdeclarative.h"
#include "qdeclarativecontext.h"
#include "private/qdeclarativeglobal_p.h"
#include "private/qdeclarativedebugtrace_p.h"

#include <QtCore/qstringbuilder.h>
#include <QtCore/qdebug.h>

QT_BEGIN_NAMESPACE

class QDeclarativeBoundSignalParameters : public QObject
{
Q_OBJECT
public:
    QDeclarativeBoundSignalParameters(const QMetaMethod &, QObject * = 0);
    ~QDeclarativeBoundSignalParameters();

    void setValues(void **);
    void clearValues();

private:
    friend class MetaObject;
    int metaCall(QMetaObject::Call, int _id, void **);
    struct MetaObject : public QAbstractDynamicMetaObject {
        MetaObject(QDeclarativeBoundSignalParameters *b)
            : parent(b) {}

        int metaCall(QMetaObject::Call c, int id, void **a) { 
            return parent->metaCall(c, id, a);
        }
        QDeclarativeBoundSignalParameters *parent;
    };

    int *types;
    void **values;
    QMetaObject *myMetaObject;
};

static int evaluateIdx = -1;

QDeclarativeAbstractBoundSignal::QDeclarativeAbstractBoundSignal(QObject *parent)
: QObject(parent)
{
}

QDeclarativeAbstractBoundSignal::~QDeclarativeAbstractBoundSignal()
{
}

QDeclarativeBoundSignal::QDeclarativeBoundSignal(QObject *scope, const QMetaMethod &signal, 
                               QObject *parent)
: m_expression(0), m_signal(signal), m_paramsValid(false), m_isEvaluating(false), m_params(0),
  m_scope(scope, this)
{
    init(parent);
}

QDeclarativeBoundSignal::QDeclarativeBoundSignal(QDeclarativeContext *ctxt, const QString &val, 
                               QObject *scope, const QMetaMethod &signal,
                               QObject *parent)
: m_expression(0), m_signal(signal), m_paramsValid(false), m_isEvaluating(false), m_params(0),
  m_scope(scope, this)
{
    init(parent);
    m_expression = new QDeclarativeExpression(ctxt, scope, val);
}

void QDeclarativeBoundSignal::init(QObject *parent)
{
    // This is thread safe.  Although it may be updated by two threads, they
    // will both set it to the same value - so the worst thing that can happen
    // is that they both do the work to figure it out.  Boo hoo.
    if (evaluateIdx == -1) evaluateIdx = metaObject()->methodCount();

    QDeclarative_setParent_noEvent(this, parent);
    QDeclarativePropertyPrivate::connect(m_scope, m_signal.methodIndex(), this, evaluateIdx);

    QDeclarativeData * const data = QDeclarativeData::get(m_scope, true);
    data->addBoundSignal(this);
}

QDeclarativeBoundSignal::~QDeclarativeBoundSignal()
{
    unregisterScopeObject();
    delete m_expression;
    m_expression = 0;
}

void QDeclarativeBoundSignal::disconnect()
{
    QMetaObject::disconnect(m_scope, m_signal.methodIndex(), this, evaluateIdx);
    QObjectPrivate * const priv = QObjectPrivate::get(m_scope);
    QVarLengthArray<char> signalSignature;
    QObjectPrivate::signalSignature(m_signal, &signalSignature);
    priv->disconnectNotify(signalSignature.constData());
}

int QDeclarativeBoundSignal::index() const 
{ 
    return m_signal.methodIndex();
}

QDeclarativeExpression *QDeclarativeBoundSignal::expression() const
{
    return m_expression;
}

QDeclarativeExpression *QDeclarativeBoundSignal::setExpression(QDeclarativeExpression *e)
{
    QDeclarativeExpression *rv = m_expression;
    m_expression = e;
    if (m_expression) m_expression->setNotifyOnValueChanged(false);
    return rv;
}

QDeclarativeBoundSignal *QDeclarativeBoundSignal::cast(QObject *o)
{
    QDeclarativeAbstractBoundSignal *s = qobject_cast<QDeclarativeAbstractBoundSignal*>(o);
    return static_cast<QDeclarativeBoundSignal *>(s);
}

int QDeclarativeBoundSignal::qt_metacall(QMetaObject::Call c, int id, void **a)
{
    if (c == QMetaObject::InvokeMetaMethod && id == evaluateIdx) {
        if (!m_expression)
            return -1;
        if (QDeclarativeDebugService::isDebuggingEnabled()) {
            QDeclarativeDebugTrace::startRange(QDeclarativeDebugTrace::HandlingSignal);
            QDeclarativeDebugTrace::rangeData(QDeclarativeDebugTrace::HandlingSignal, QLatin1String(m_signal.signature()) % QLatin1String(": ") % m_expression->expression());
            QDeclarativeDebugTrace::rangeLocation(QDeclarativeDebugTrace::HandlingSignal, m_expression->sourceFile(), m_expression->lineNumber());
        }
        m_isEvaluating = true;
        if (!m_paramsValid) {
            if (!m_signal.parameterTypes().isEmpty())
                m_params = new QDeclarativeBoundSignalParameters(m_signal, this);
            m_paramsValid = true;
        }

        if (m_params) m_params->setValues(a);
        if (m_expression && m_expression->engine()) {
            QDeclarativeExpressionPrivate::get(m_expression)->value(m_params);
            if (m_expression && m_expression->hasError())
                QDeclarativeEnginePrivate::warning(m_expression->engine(), m_expression->error());
        }
        if (m_params) m_params->clearValues();
        m_isEvaluating = false;
        QDeclarativeDebugTrace::endRange(QDeclarativeDebugTrace::HandlingSignal);
        return -1;
    } else {
        return QObject::qt_metacall(c, id, a);
    }
}

void QDeclarativeBoundSignal::unregisterScopeObject()
{
    if (m_scope) {
        QDeclarativeData * const data = QDeclarativeData::get(m_scope, false);
        if (data)
            data->removeBoundSignal(this);
    }
}

QDeclarativeBoundSignalParameters::QDeclarativeBoundSignalParameters(const QMetaMethod &method, 
                                                                     QObject *parent)
: QObject(parent), types(0), values(0)
{
    MetaObject *mo = new MetaObject(this);

    // ### Optimize!
    QMetaObjectBuilder mob;
    mob.setSuperClass(&QDeclarativeBoundSignalParameters::staticMetaObject);
    mob.setClassName("QDeclarativeBoundSignalParameters");

    QList<QByteArray> paramTypes = method.parameterTypes();
    QList<QByteArray> paramNames = method.parameterNames();
    types = new int[paramTypes.count()];
    for (int ii = 0; ii < paramTypes.count(); ++ii) {
        const QByteArray &type = paramTypes.at(ii);
        const QByteArray &name = paramNames.at(ii);

        if (name.isEmpty() || type.isEmpty()) {
            types[ii] = 0;
            continue;
        }

        QVariant::Type t = (QVariant::Type)QMetaType::type(type.constData());
        if (QDeclarativeMetaType::isQObject(t)) {
            types[ii] = QMetaType::QObjectStar;
            QMetaPropertyBuilder prop = mob.addProperty(name, "QObject*");
            prop.setWritable(false);
        } else {
            QByteArray propType = type;
            if (t >= QVariant::UserType || t == QVariant::Invalid) {
                //copy of QDeclarativeObjectScriptClass::enumType()
                QByteArray scope;
                QByteArray name;
                int scopeIdx = propType.lastIndexOf("::");
                if (scopeIdx != -1) {
                    scope = propType.left(scopeIdx);
                    name = propType.mid(scopeIdx + 2);
                } else {
                    name = propType;
                }
                const QMetaObject *meta;
                if (scope == "Qt")
                    meta = &QObject::staticQtMetaObject;
                else
                    meta = parent->parent()->metaObject();   //### assumes parent->parent()
                for (int i = meta->enumeratorCount() - 1; i >= 0; --i) {
                    QMetaEnum m = meta->enumerator(i);
                    if ((m.name() == name) && (scope.isEmpty() || (m.scope() == scope))) {
                        t = QVariant::Int;
                        propType = "int";
                        break;
                    }
                }
            }
            if (QDeclarativeMetaType::canCopy(t)) {
                types[ii] = t;
                QMetaPropertyBuilder prop = mob.addProperty(name, propType);
                prop.setWritable(false);
            } else {
                types[ii] = 0x80000000 | t;
                QMetaPropertyBuilder prop = mob.addProperty(name, "QVariant");
                prop.setWritable(false);
            }
        }
    }
    myMetaObject = mob.toMetaObject();
    *static_cast<QMetaObject *>(mo) = *myMetaObject;

    d_ptr->metaObject = mo;
}

QDeclarativeBoundSignalParameters::~QDeclarativeBoundSignalParameters()
{
    delete [] types;
    qFree(myMetaObject);
}

void QDeclarativeBoundSignalParameters::setValues(void **v)
{
    values = v;
}

void QDeclarativeBoundSignalParameters::clearValues()
{
    values = 0;
}

int QDeclarativeBoundSignalParameters::metaCall(QMetaObject::Call c, int id, void **a)
{
    if (!values)
        return -1;

    if (c == QMetaObject::ReadProperty && id >= 1) {
        if (types[id - 1] & 0x80000000) {
            *((QVariant *)a[0]) = QVariant(types[id - 1] & 0x7FFFFFFF, values[id]);
        } else {
            QDeclarativeMetaType::copy(types[id - 1], a[0], values[id]);
        }
        return -1;
    } else {
        return qt_metacall(c, id, a);
    }
}

QT_END_NAMESPACE

#include <qdeclarativeboundsignal.moc>