private void SetExpenseTotals(TripMemberCollection members)
{
foreach (var member in members.TripMembers)
member.TotalExpense = member.Expenses.Sum();
members.TotalExpense = members.TripMembers.Sum(m => m.TotalExpense);
members.TotalExpenseAverage = members.TotalExpense/members.TripMembers.Count();
}
public TripSettlementCollection GetSettlements(TripMemberCollection members)
{
SetExpenseTotals(members);
SetAmountOwed(members);
var settlements = GetCalculatedSettlements(members);
return new TripSettlementCollection { Settlements = settlements };
}
private IEnumerable<TripSettlement> GetCalculatedSettlements(TripMemberCollection members)
{
var orderedMembers = GetOrderedMembers(members);
foreach (var sender in GetSenders(orderedMembers))
{
foreach (var receiver in GetReceivers(orderedMembers))
{
var transferrableAmount = GetMaximumTransferrableAmount(sender, receiver);
sender.AmountTransferred += transferrableAmount;
receiver.AmountTransferred -= transferrableAmount;
yield return new TripSettlement
{
SenderName = sender.Name,
ReceiverName = receiver.Name,
Amount = transferrableAmount
};
}
}
}
private TripMemberCollection GetTwoMemberExpensesCollection()
{
var purchases = new TripMemberCollection
{
TripMembers = new List<TripMember>
{
new TripMember
{
Name = "Amber",
Expenses = new[] {1.01M, 1.12M, 2.23M, 3.34M, 5.45M, 8.56M}
},
new TripMember
{
Name = "Brandon",
Expenses = new[] {2.21M, 3.33M, 6.43M, 9.67M, 15.98M, 28.99M}
}
}
};
return purchases;
}
private TripMemberCollection GetThreeMemberExpensesCollection()
{
var purchases = new TripMemberCollection
{
TripMembers = new List<TripMember>
{
new TripMember
{
Name = "Amber",
Expenses = new[] { 1.25M, 1.50M, 5.67M, 98.41M }
},
new TripMember
{
Name = "Brandon",
Expenses = new[] { 49.96M, 87.12M, 105.78M }
},
new TripMember
{
Name = "Catherine",
Expenses = new[] { 1.01M, 1.12M, 2.23M, 3.34M, 5.45M, 8.56M }
}
}
};
return purchases;
}
private TripMemberCollection GetOneMemberExpenseCollection()
{
var purchases = new TripMemberCollection
{
TripMembers = new List<TripMember>
{
new TripMember
{
Name = "Amber",
Expenses = new[] {0M, 1.01M, 1.12M, 2.23M, 3.34M, 5.45M, 8.56M}
}
}
};
return purchases;
}
private void SetAmountOwed(TripMemberCollection members)
{
foreach (var member in members.TripMembers)
member.AmountOwed = member.TotalExpense - members.TotalExpenseAverage;
}
private List<TripMember> GetOrderedMembers(TripMemberCollection members)
{
return members.TripMembers.OrderBy(m => m.AmountOwed).ToList();
}