// note new inflight unit from the current study plan
private void PickUnit(UnitInPlan unit)
{
oldPosition = unit.semester;
plan.Remove(unit);
inFlightUnitCode = unit.code;
inFlightStudyArea = unit.studyArea;
}
private static StudyPlan scheduleRemaning(IEnumerable <PlannedUnit> remainingUnits, StudyPlan plannedUnits)
{
try
{
if (!remainingUnits.Any())
{
return(plannedUnits);
}
PlannedUnit schedulableUnit =
remainingUnits.First(
unit => unit.possibleSemesters.Where(
sem => StudyPlannerModel.isEnrollableIn(unit.code, sem, plannedUnits)
).Any()
);
foreach (var sem in schedulableUnit.possibleSemesters)
{
if (StudyPlannerModel.isEnrollableIn(schedulableUnit.code, sem, plannedUnits))
{
UnitInPlan newUnitPlan = new UnitInPlan(schedulableUnit.code, schedulableUnit.studyArea, sem);
StudyPlan scheduleEachSem = scheduleRemaning(remainingUnits.Where(unit => unit.code != schedulableUnit.code), plannedUnits.Concat(new UnitInPlan[] { newUnitPlan }));
if (scheduleEachSem != null)
{
return(scheduleEachSem);
}
}
}
}catch (Exception ex) //if can't find any schedulable unit while there are still units needed to add to the plan
{
return(null);
}
return(null); //if can't add all the remaining units
}
public static StudyPlan scheduleRemaining(List <PlannedUnit> boundUnits, List <UnitInPlan> plan)
{
if (boundUnits.Count == 0) // all units have been scheduled, so return plan
{
return(plan);
}
PlannedUnit firstUnit = boundUnits.FirstOrDefault(unit => unit.possibleSemesters
.Any(sem => StudyPlannerModel.isEnrollableIn(unit.code, sem, plan)));
if (firstUnit is null) // we have failed in finding an enrollable unit, so cannot complete schedule
{
return(null);
}
// otherwise schedule in possible semester
foreach (Semester sem in firstUnit.possibleSemesters)
{
if (StudyPlannerModel.isEnrollableIn(firstUnit.code, sem, plan))
{
UnitInPlan newUnit = new UnitInPlan(firstUnit.code, firstUnit.studyArea, sem);
IEnumerable <UnitInPlan> newPlan = plan.Append(newUnit); // add new unit to plan
IEnumerable <PlannedUnit> newBound = boundUnits.Where(subject => subject.code != newUnit.code); // remove new unit from planned units
StudyPlan final = scheduleRemaining(newBound.ToList(), newPlan.ToList()); // try to schedule the rest of the planned units
// if we finish with a plan that is not null, then we hav succeeded and return plan
if (!(final is null))
{
return(final);
}
}
}
// otherwise no possible choices
return(null);
}
