qstate.cpp

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#include "qstate.h"

#ifndef QT_NO_STATEMACHINE

#include "qstate_p.h"
#include "qhistorystate.h"
#include "qhistorystate_p.h"
#include "qabstracttransition.h"
#include "qabstracttransition_p.h"
#include "qsignaltransition.h"
#include "qstatemachine.h"
#include "qstatemachine_p.h"

QT_BEGIN_NAMESPACE

QStatePrivate::QStatePrivate()
    : QAbstractStatePrivate(StandardState),
      errorState(0), initialState(0), childMode(QState::ExclusiveStates),
      childStatesListNeedsRefresh(true), transitionsListNeedsRefresh(true)
{
}

QStatePrivate::~QStatePrivate()
{
}

void QStatePrivate::emitFinished()
{
    Q_Q(QState);
    emit q->finished();
}

void QStatePrivate::emitPropertiesAssigned()
{
    Q_Q(QState);
    emit q->propertiesAssigned();
}

QState::QState(QState *parent)
    : QAbstractState(*new QStatePrivate, parent)
{
}

QState::QState(ChildMode childMode, QState *parent)
    : QAbstractState(*new QStatePrivate, parent)
{
    Q_D(QState);
    d->childMode = childMode;
}

QState::QState(QStatePrivate &dd, QState *parent)
    : QAbstractState(dd, parent)
{
}

QState::~QState()
{
}

QList<QAbstractState*> QStatePrivate::childStates() const
{
    if (childStatesListNeedsRefresh) {
        childStatesList.clear();
        QList<QObject*>::const_iterator it;
        for (it = children.constBegin(); it != children.constEnd(); ++it) {
            QAbstractState *s = qobject_cast<QAbstractState*>(*it);
            if (!s || qobject_cast<QHistoryState*>(s))
                continue;
            childStatesList.append(s);
        }
        childStatesListNeedsRefresh = false;
    }
    return childStatesList;
}

QList<QHistoryState*> QStatePrivate::historyStates() const
{
    QList<QHistoryState*> result;
    QList<QObject*>::const_iterator it;
    for (it = children.constBegin(); it != children.constEnd(); ++it) {
        QHistoryState *h = qobject_cast<QHistoryState*>(*it);
        if (h)
            result.append(h);
    }
    return result;
}

QList<QAbstractTransition*> QStatePrivate::transitions() const
{
    if (transitionsListNeedsRefresh) {
        transitionsList.clear();
        QList<QObject*>::const_iterator it;
        for (it = children.constBegin(); it != children.constEnd(); ++it) {
            QAbstractTransition *t = qobject_cast<QAbstractTransition*>(*it);
            if (t)
                transitionsList.append(t);
        }
        transitionsListNeedsRefresh = false;
    }
    return transitionsList;
}

#ifndef QT_NO_PROPERTIES

void QState::assignProperty(QObject *object, const char *name,
                            const QVariant &value)
{
    Q_D(QState);
    if (!object) {
        qWarning("QState::assignProperty: cannot assign property '%s' of null object", name);
        return;
    }
    for (int i = 0; i < d->propertyAssignments.size(); ++i) {
        QPropertyAssignment &assn = d->propertyAssignments[i];
        if ((assn.object == object) && (assn.propertyName == name)) {
            assn.value = value;
            return;
        }
    }
    d->propertyAssignments.append(QPropertyAssignment(object, name, value));
}

#endif // QT_NO_PROPERTIES

QAbstractState *QState::errorState() const
{
    Q_D(const QState);
    return d->errorState;
}

void QState::setErrorState(QAbstractState *state)
{
    Q_D(QState);
    if (state != 0 && qobject_cast<QStateMachine*>(state)) {
        qWarning("QStateMachine::setErrorState: root state cannot be error state");
        return;
    }
    if (state != 0 && (!state->machine() || ((state->machine() != machine()) && !qobject_cast<QStateMachine*>(this)))) {
        qWarning("QState::setErrorState: error state cannot belong "
                 "to a different state machine");
        return;
    }

    d->errorState = state;
}

void QState::addTransition(QAbstractTransition *transition)
{
    Q_D(QState);
    if (!transition) {
        qWarning("QState::addTransition: cannot add null transition");
        return ;
    }

    transition->setParent(this);
    const QList<QWeakPointer<QAbstractState> > &targets = QAbstractTransitionPrivate::get(transition)->targetStates;
    for (int i = 0; i < targets.size(); ++i) {
        QAbstractState *t = targets.at(i).data();
        if (!t) {
            qWarning("QState::addTransition: cannot add transition to null state");
            return ;
        }
        if ((QAbstractStatePrivate::get(t)->machine() != d->machine())
            && QAbstractStatePrivate::get(t)->machine() && d->machine()) {
            qWarning("QState::addTransition: cannot add transition "
                     "to a state in a different state machine");
            return ;
        }
    }
    if (machine() != 0 && machine()->configuration().contains(this))
        QStateMachinePrivate::get(machine())->registerTransitions(this);
}

QSignalTransition *QState::addTransition(QObject *sender, const char *signal,
                                         QAbstractState *target)
{
    if (!sender) {
        qWarning("QState::addTransition: sender cannot be null");
        return 0;
    }
    if (!signal) {
        qWarning("QState::addTransition: signal cannot be null");
        return 0;
    }
    if (!target) {
        qWarning("QState::addTransition: cannot add transition to null state");
        return 0;
    }
    int offset = (*signal == '0'+QSIGNAL_CODE) ? 1 : 0;
    const QMetaObject *meta = sender->metaObject();
    if (meta->indexOfSignal(signal+offset) == -1) {
        if (meta->indexOfSignal(QMetaObject::normalizedSignature(signal+offset)) == -1) {
            qWarning("QState::addTransition: no such signal %s::%s",
                     meta->className(), signal+offset);
            return 0;
        }
    }
    QSignalTransition *trans = new QSignalTransition(sender, signal);
    trans->setTargetState(target);
    addTransition(trans);
    return trans;
}

namespace {

// ### Make public?
class UnconditionalTransition : public QAbstractTransition
{
public:
    UnconditionalTransition(QAbstractState *target)
        : QAbstractTransition()
    { setTargetState(target); }
protected:
    void onTransition(QEvent *) {}
    bool eventTest(QEvent *) { return true; }
};

} // namespace

QAbstractTransition *QState::addTransition(QAbstractState *target)
{
    if (!target) {
        qWarning("QState::addTransition: cannot add transition to null state");
        return 0;
    }
    UnconditionalTransition *trans = new UnconditionalTransition(target);
    addTransition(trans);
    return trans;
}

void QState::removeTransition(QAbstractTransition *transition)
{
    Q_D(QState);
    if (!transition) {
        qWarning("QState::removeTransition: cannot remove null transition");
        return;
    }
    if (transition->sourceState() != this) {
        qWarning("QState::removeTransition: transition %p's source state (%p)"
                 " is different from this state (%p)",
                 transition, transition->sourceState(), this);
        return;
    }
    QStateMachinePrivate *mach = QStateMachinePrivate::get(d->machine());
    if (mach)
        mach->unregisterTransition(transition);
    transition->setParent(0);
}

QList<QAbstractTransition*> QState::transitions() const
{
    Q_D(const QState);
    return d->transitions();
}

void QState::onEntry(QEvent *event)
{
    Q_UNUSED(event);
}

void QState::onExit(QEvent *event)
{
    Q_UNUSED(event);
}

QAbstractState *QState::initialState() const
{
    Q_D(const QState);
    return d->initialState;
}

void QState::setInitialState(QAbstractState *state)
{
    Q_D(QState);
    if (d->childMode == QState::ParallelStates) {
        qWarning("QState::setInitialState: ignoring attempt to set initial state "
                 "of parallel state group %p", this);
        return;
    }
    if (state && (state->parentState() != this)) {
        qWarning("QState::setInitialState: state %p is not a child of this state (%p)",
                 state, this);
        return;
    }
    d->initialState = state;
}

QState::ChildMode QState::childMode() const
{
    Q_D(const QState);
    return d->childMode;
}

void QState::setChildMode(ChildMode mode)
{
    Q_D(QState);
    d->childMode = mode;
}

bool QState::event(QEvent *e)
{
    Q_D(QState);
    if ((e->type() == QEvent::ChildAdded) || (e->type() == QEvent::ChildRemoved)) {
        d->childStatesListNeedsRefresh = true;
        d->transitionsListNeedsRefresh = true;
    }
    return QAbstractState::event(e);
}

QT_END_NAMESPACE

#endif //QT_NO_STATEMACHINE