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#include "private/qdeclarativestategroup_p.h"

#include "private/qdeclarativetransition_p.h"

#include "private/qdeclarativestate_p_p.h"

#include <qdeclarativebinding_p.h>

#include <qdeclarativeglobal_p.h>

#include <QtCore/qstringbuilder.h>

#include <QtCore/qdebug.h>

#include <private/qobject_p.h>

#include <qdeclarativeinfo.h>

QT_BEGIN_NAMESPACE

DEFINE_BOOL_CONFIG_OPTION(stateChangeDebug, STATECHANGE_DEBUG);

class QDeclarativeStateGroupPrivate : public QObjectPrivate

{

    Q_DECLARE_PUBLIC(QDeclarativeStateGroup)

public:

    QDeclarativeStateGroupPrivate()

    : nullState(0), componentComplete(true),

      ignoreTrans(false), applyingState(false), unnamedCount(0) {}

    QString currentState;

    QDeclarativeState *nullState;

    static void append_state(QDeclarativeListProperty<QDeclarativeState> *list, QDeclarativeState *state);

    static int count_state(QDeclarativeListProperty<QDeclarativeState> *list);

    static QDeclarativeState *at_state(QDeclarativeListProperty<QDeclarativeState> *list, int index);

    static void clear_states(QDeclarativeListProperty<QDeclarativeState> *list);

    QList<QDeclarativeState *> states;

    QList<QDeclarativeTransition *> transitions;

    bool componentComplete;

    bool ignoreTrans;

    bool applyingState;

    int unnamedCount;

    QDeclarativeTransition *findTransition(const QString &from, const QString &to);

    void setCurrentStateInternal(const QString &state, bool = false);

    bool updateAutoState();

};

/*!

   \qmlclass StateGroup QDeclarativeStateGroup

   \since 4.7

   \brief The StateGroup element provides state support for non-Item elements.

   Item (and all derived elements) provides built in support for states and transitions

   via its \l{Item::state}{state}, \l{Item::states}{states} and \l{Item::transitions}{transitions} properties. StateGroup provides an easy way to

   use this support in other (non-Item-derived) elements.

   \qml

   MyCustomObject {

       StateGroup {

           id: myStateGroup

           states: State {

               name: "state1"

               ...

           }

           transitions: Transition {

               ...

           }

       }

       onSomethingHappened: myStateGroup.state = "state1";

   }

   \endqml

*/

QDeclarativeStateGroup::QDeclarativeStateGroup(QObject *parent)

    : QObject(*(new QDeclarativeStateGroupPrivate), parent)

{

}

QDeclarativeStateGroup::~QDeclarativeStateGroup()

{

    Q_D(const QDeclarativeStateGroup);

    for (int i = 0; i < d->states.count(); ++i)

        d->states.at(i)->setStateGroup(0);

}

QList<QDeclarativeState *> QDeclarativeStateGroup::states() const

{

    Q_D(const QDeclarativeStateGroup);

    return d->states;

}

/*!

  \qmlproperty list<State> StateGroup::states

  This property holds a list of states defined by the state group.

  \qml

  StateGroup {

    states: [

      State { ... },

      State { ... }

      ...

    ]

  }

  \endqml

  \sa {qmlstate}{States}

*/

QDeclarativeListProperty<QDeclarativeState> QDeclarativeStateGroup::statesProperty()

{

    Q_D(QDeclarativeStateGroup);

    return QDeclarativeListProperty<QDeclarativeState>(this, &d->states, &QDeclarativeStateGroupPrivate::append_state,

                                                       &QDeclarativeStateGroupPrivate::count_state,

                                                       &QDeclarativeStateGroupPrivate::at_state,

                                                       &QDeclarativeStateGroupPrivate::clear_states);

}

void QDeclarativeStateGroupPrivate::append_state(QDeclarativeListProperty<QDeclarativeState> *list, QDeclarativeState *state)

{

    QDeclarativeStateGroup *_this = static_cast<QDeclarativeStateGroup *>(list->object);

    if (state) {

        _this->d_func()->states.append(state);

        state->setStateGroup(_this);

    }

}

int QDeclarativeStateGroupPrivate::count_state(QDeclarativeListProperty<QDeclarativeState> *list)

{

    QDeclarativeStateGroup *_this = static_cast<QDeclarativeStateGroup *>(list->object);

    return _this->d_func()->states.count();

}

QDeclarativeState *QDeclarativeStateGroupPrivate::at_state(QDeclarativeListProperty<QDeclarativeState> *list, int index)

{

    QDeclarativeStateGroup *_this = static_cast<QDeclarativeStateGroup *>(list->object);

    return _this->d_func()->states.at(index);

}

void QDeclarativeStateGroupPrivate::clear_states(QDeclarativeListProperty<QDeclarativeState> *list)

{

    QDeclarativeStateGroup *_this = static_cast<QDeclarativeStateGroup *>(list->object);

    _this->d_func()->setCurrentStateInternal(QString(), true);

    for (int i = 0; i < _this->d_func()->states.count(); ++i) {

        _this->d_func()->states.at(i)->setStateGroup(0);

    }

    _this->d_func()->states.clear();

}

/*!

  \qmlproperty list<Transition> StateGroup::transitions

  This property holds a list of transitions defined by the state group.

  \qml

  StateGroup {

    transitions: [

      Transition { ... },

      Transition { ... }

      ...

    ]

  }

  \endqml

*/

QDeclarativeListProperty<QDeclarativeTransition> QDeclarativeStateGroup::transitionsProperty()

{

    Q_D(QDeclarativeStateGroup);

    return QDeclarativeListProperty<QDeclarativeTransition>(this, d->transitions);

}

/*!

  \qmlproperty string StateGroup::state

  This property holds the name of the current state of the state group.

  This property is often used in scripts to change between states. For

  example:

  \qml

    function toggle() {

        if (button.state == 'On')

            button.state = 'Off';

        else

            button.state = 'On';

    }

  \endqml

  If the state group is in its base state (i.e. no explicit state has been

  set), \c state will be a blank string. Likewise, you can return a

  state group to its base state by setting its current state to \c ''.

  \sa {qmlstates}{States}

*/

QString QDeclarativeStateGroup::state() const

{

    Q_D(const QDeclarativeStateGroup);

    return d->currentState;

}

void QDeclarativeStateGroup::setState(const QString &state)

{

    Q_D(QDeclarativeStateGroup);

    if (d->currentState == state)

        return;

    d->setCurrentStateInternal(state);

}

void QDeclarativeStateGroup::classBegin()

{

    Q_D(QDeclarativeStateGroup);

    d->componentComplete = false;

}

void QDeclarativeStateGroup::componentComplete()

{

    Q_D(QDeclarativeStateGroup);

    d->componentComplete = true;

    for (int ii = 0; ii < d->states.count(); ++ii) {

        QDeclarativeState *state = d->states.at(ii);

        if (!state->isNamed())

            state->setName(QLatin1String("anonymousState") % QString::number(++d->unnamedCount));

    }

    if (d->updateAutoState()) {

        return;

    } else if (!d->currentState.isEmpty()) {

        QString cs = d->currentState;

        d->setCurrentStateInternal(cs, true);

    }

}

/*!

    Returns true if the state was changed, otherwise false.

*/

bool QDeclarativeStateGroup::updateAutoState()

{

    Q_D(QDeclarativeStateGroup);

    return d->updateAutoState();

}

bool QDeclarativeStateGroupPrivate::updateAutoState()

{

    Q_Q(QDeclarativeStateGroup);

    if (!componentComplete)

        return false;

    bool revert = false;

    for (int ii = 0; ii < states.count(); ++ii) {

        QDeclarativeState *state = states.at(ii);

        if (state->isWhenKnown()) {

            if (state->isNamed()) {

                if (state->when() && state->when()->evaluate().toBool()) {

                    if (stateChangeDebug()) 

                        qWarning() << "Setting auto state due to:" 

                                   << state->when()->expression();

                    if (currentState != state->name()) {

                        q->setState(state->name());

                        return true;

                    } else {

                        return false;

                    }

                } else if (state->name() == currentState) {

                    revert = true;

                }

            }

        }

    }

    if (revert) {

        q->setState(QString());

        return rv;

    } else {

        return false;

    }

}

QDeclarativeTransition *QDeclarativeStateGroupPrivate::findTransition(const QString &from, const QString &to)

{

    QDeclarativeTransition *highest = 0;

    int score = 0;

    bool reversed = false;

    bool done = false;

    for (int ii = 0; !done && ii < transitions.count(); ++ii) {

        QDeclarativeTransition *t = transitions.at(ii);

        for (int ii = 0; ii < 2; ++ii)

        {

            if (ii && (!t->reversible() ||

                      (t->fromState() == QLatin1String("*") && 

                       t->toState() == QLatin1String("*"))))

                break;

            QStringList fromState;

            QStringList toState;

            fromState = t->fromState().split(QLatin1Char(','));

            toState = t->toState().split(QLatin1Char(','));

            if (ii == 1)

                qSwap(fromState, toState);

            int tScore = 0;

            if (fromState.contains(from))

                tScore += 2;

            else if (fromState.contains(QLatin1String("*")))

                tScore += 1;

            else

                continue;

            if (toState.contains(to))

                tScore += 2;

            else if (toState.contains(QLatin1String("*")))

                tScore += 1;

            else

                continue;

            if (ii == 1)

                reversed = true;

            else

                reversed = false;

            if (tScore == 4) {

                highest = t;

                done = true;

                break;

            } else if (tScore > score) {

                score = tScore;

                highest = t;

            }

        }

    }

    if (highest)

        highest->setReversed(reversed);

    return highest;

}

void QDeclarativeStateGroupPrivate::setCurrentStateInternal(const QString &state, 

                                                   bool ignoreTrans)

{

    Q_Q(QDeclarativeStateGroup);

    if (!componentComplete) {

        currentState = state;

        return;

    }

    if (applyingState) {

        qmlInfo(q) << "Can't apply a state change as part of a state definition.";

        return;

    }

    applyingState = true;

    QDeclarativeTransition *transition = (ignoreTrans || ignoreTrans) ? 0 : findTransition(currentState, state);

    if (stateChangeDebug()) {

        qWarning() << this << "Changing state.  From" << currentState << ". To" << state;

        if (transition)

            qWarning() << "   using transition" << transition->fromState() 

                       << transition->toState();

    }

    QDeclarativeState *oldState = 0;

    if (!currentState.isEmpty()) {

        for (int ii = 0; ii < states.count(); ++ii) {

            if (states.at(ii)->name() == currentState) {

                oldState = states.at(ii);

                break;

            }

        }

    }

    currentState = state;

    emit q->stateChanged(currentState);

    QDeclarativeState *newState = 0;

    for (int ii = 0; ii < states.count(); ++ii) {

        if (states.at(ii)->name() == currentState) {

            newState = states.at(ii);

            break;

        }

    }

    if (oldState == 0 || newState == 0) {

        if (!nullState) { nullState = new QDeclarativeState; QDeclarative_setParent_noEvent(nullState, q); }

        if (!oldState) oldState = nullState;

        if (!newState) newState = nullState;

    }

    newState->apply(q, transition, oldState);

    applyingState = false;

    if (!transition)

        static_cast<QDeclarativeStatePrivate*>(QObjectPrivate::get(newState))->complete();

}

QDeclarativeState *QDeclarativeStateGroup::findState(const QString &name) const

{

    Q_D(const QDeclarativeStateGroup);

    for (int i = 0; i < d->states.count(); ++i) {

        QDeclarativeState *state = d->states.at(i);

        if (state->name() == name)

            return state;

    }

    return 0;

}

void QDeclarativeStateGroup::removeState(QDeclarativeState *state)

{

    Q_D(QDeclarativeStateGroup);

    d->states.removeOne(state);

}

QT_END_NAMESPACE