/// <summary>
/// Use case implementation of PayBills.
/// </summary>
public static void PayBills(this PayBills.SourceAccountRole sourceAccount)
{
// Get the current Context first.
var c = Context.Current <PayBills>(sourceAccount, ct => ct.SourceAccount);
// Get the current Creditor list, enumerating it to a list so it's not modified during the operation.
var creditors = c.Creditors.ToList();
// If not enough money to pay all creditors, don't pay anything.
var surplus = sourceAccount.Balance - creditors.Sum(cr => cr.AmountOwed);
if (surplus < 0)
{
throw new AccountException(
string.Format("Not enough money on account to pay all bills.\r\n{0:c} more is needed.", Math.Abs(surplus)));
}
creditors.ForEach(creditor =>
{
// For each creditor, create a MoneyTransfer Context.
var transferContext = new MoneyTransfer(sourceAccount, creditor.Account, creditor.AmountOwed);
// When the whole context object can be supplied to Context.Execute, there
// is no need to set the context explicitly. Context.Execute will look for
// a method called Execute and invoke it.
//
// If another method than Execute must be invoked, use the Action overload.
Context.Execute(transferContext);
});
}
// When the Context is created, the Roles will be bound using the supplied arguments.
// There can be multiple constructors with different ways of retreiving the objects
// needed for the binding (database lookup, web service, etc), but there can only be
// one BindRoles method, which does the final Role binding.
// The constructor(s) should be strongly typed to check for errors.
public MoneyTransfer(PayBills.SourceAccountRole source, Account destination, decimal amount)
{
BindRoles(source, destination, amount);
}
