public SantaList GenerateSantaList(IList<Contact> contacts, IList<Restriction> restrictions)
{
// go through all contacts and pick another contact as the
// order contacts by the number of restrictions they have
var orderedByRestrictions = SortByRestrictions(contacts, restrictions).ToList();
Random rng = new Random();
var remainingReceivers = new List<Contact>(orderedByRestrictions);
var santasList = new SantaList();
foreach (var santa in orderedByRestrictions)
{
var withoutSelf = RemoveSelfFromList(remainingReceivers, santa);
var restrictionsForSanta = restrictions.Where(r => r.Between.Id == santa.Id);
var possibleReceivers = RemoveRestrictionsFromList(withoutSelf, restrictionsForSanta);
if (possibleReceivers.Count == 0)
throw new Exception("No options left, try again");
int randomIndex = rng.Next(possibleReceivers.Count);
var randomReceiver = possibleReceivers[randomIndex];
remainingReceivers.Remove(randomReceiver);
var entry = new SantaEntry(santa, randomReceiver);
santasList.AddEntry(entry);
}
return santasList;
}
public virtual void AddEntry(SantaEntry entry)
{
SantaEntries.Add(entry);
}