/* function : rollBack ()
UNDO all actions that occured after the last leap of faith.
in other words : rollback until you reach a leap of faith action.
if this action reaches a (BOARD_INITIALIZED) action before reaching
a (LEAP_OF_FAITH) action, it considers that the initial state of
the board is an invalid state and impossible to solve.
in the later case, this function sets the state flag (_BAD_INITIALIZATION).
return type :
- if rolled back successfully : true.
- otherwise : false.
*/
bool actionCourse::rollBack()
{
do
{
if( lastAction() . act == actionRecord::BOARD_INITIALIZED)
{
// if reached the BOARD_INITIALIZED action ...
// set the state flag _BAD_INITIALIZATION
dynamic_cast<sudokuBoard*>(this)->state |= sudokuState::_BAD_INITIALIZATION;
return false;
}
else
Undo();
}
// keep rolling back until you reach a LEAP_OF_FAITH action.
while( Tracker.top() != actionRecord::LEAP_OF_FAITH );
// signal the current value as faulty and shouldn't be used for future leaps.
Tracker.top().faultyValues.push_back(*(lastAction().subject));
if( Tracker.top().faultyValues.size() < (unsigned)Tracker.top().subject->countPossibilities() )
//correct the value taken by the leap
return Correct_LeapOfFaith();
else if(Tracker.top().subject->countPossibilities() == Tracker.top().faultyValues.size() )
return rollBack(); //if all the possibilities are tried, then a previuos leap is the mistake, roll back another time.
else
return false; // report failure.
}
void testlastAction() {
GameProperties newGame = getGame(NULL);
delayGame(ACTIONCOOLDOWN);
sput_fail_unless(lastAction(newGame) == 1,"Checking delay more than Cooldown returns true");
delayGame(ACTIONCOOLDOWN-1);
sput_fail_unless(lastAction(newGame) == 0,"Checking delay less than Cooldown returns false");
}
void testlastAction() {
GameProperties newGame = createGame();
delayGame(ACTIONCOOLDOWN);
sput_fail_unless(lastAction(newGame) == 1,"Checking delay more than Cooldown returns true");
delayGame(ACTIONCOOLDOWN-1);
sput_fail_unless(lastAction(newGame) == 0,"Checking delay less than Cooldown returns false");
free(newGame->clock);
free(newGame);
}
void QompQtMultimediaPlayer::tuneUrlReady(const QUrl &url)
{
#ifdef DEBUG_OUTPUT
qDebug() << "QompQtMultimediaPlayer::tuneUrlReady() " << lastAction() << url;
#endif
player_->setMedia(QMediaContent(url));
switch (lastAction()) {
case Qomp::StatePlaying: player_->play();
break;
case Qomp::StatePaused: player_->pause();
break;
default: player_->stop();
break;
}
}
/* function : Correct_LeapOfFaith ()
pre-condition : the top of the action tracker is a wrong leap of faith action.
this function corrects the error made at the last leap of faith, by choosing
a value that is valid and not specified in the faultyValues vector.
if this function fails, it sets the error stat _BAD_OPERATION and registers
a BAD_OPERATION actionRecord on top of the action course.
return value :
- if succeeded and changed the value . . . . : true
- if the value wasn't changed due to any circumstance : false
*/
bool sudokuBoard::Correct_LeapOfFaith()
{
actionRecord last = lastAction();
// check for a faulty LEAP_OF_FAITH action
if( last != actionRecord::LEAP_OF_FAITH )
{
pushAction( actionRecord ( actionRecord::BAD_OPERATION , Cell() , false) );
return false;
}
// check if the current leap is actually faulty,
// by checking if it has any faulty values.
if( last.faultyValues.size() == 0 )
{
pushAction( actionRecord ( actionRecord::BAD_OPERATION , Cell() , false) );
return false;
}
// cycle through the possibilities
for( Index i = 0 ; i<10 ; i++ )
{
// if the number contained in (i) is a valid in the subject cell:
if( last.subject->possible[i] )
{
// validate the cell to avoid any possible errors in expectations :
expectFor( *last.subject );
// check if that number exists in the faulty values:
bool IsFaulty = false;
for( Index j = 0 ; j < last.faultyValues.size() ; j++)
{
if( i == static_cast<int>(last.faultyValues[j]) )
{
IsFaulty = true;
break;
}
}
// if the value is a faulty one, then look for another :
if (IsFaulty)
continue;
// else, make this value the new choice of this leap :
else
{
// set the new value :
last.subject->v = i;
// re-validate the cell :
expectFor( *last.subject );
// report success :
return true;
}
}
}
// if execution reaches this point, then a value hasn't been changed.
// report failure.
return false;
}
