public void GiveChange(double change)
{
List <CashMoney> money = new List <CashMoney>();
List <CashMoney> changedMoney = new List <CashMoney>();
try
{
using (var db = new VendMachineDbContext())
{
money = db.Money.ToList <CashMoney>();
changedMoney = CalculateMinimum(money, change);
Console.WriteLine("Change: ");
for (int i = 0; i < changedMoney.Count; i++)
{
CashMoney coinFromChange = changedMoney[i];
Console.Write(changedMoney[i] + " ");
CashMoney cashMoney = db.Money.Where(x => x.MoneyValue == coinFromChange.MoneyValue).FirstOrDefault();
cashMoney.Quantity -= coinFromChange.Quantity;
db.Entry(cashMoney).State = EntityState.Modified;
db.SaveChanges();
}
log.Info("GIVE Change success");
}
}
catch (Exception)
{
log.Error("Fail database connection-GIVE Change");
}
}
public void AddMoney(double money)
{
if (acceptedDenominations.Contains(money))
{
CashMoney cashMoney = new CashMoney(money, 1);
IntroducedMoney.Add(cashMoney);
TotalMoney += money;
}
else
{
throw new Exception("Money not accepted");
}
}
public void UpdateMoney(double value, int quantity)
{
try
{
using (var db = new VendMachineDbContext())
{
CashMoney cashMoney = db.Money.Where(x => x.MoneyValue == value).FirstOrDefault();
cashMoney.Quantity += quantity;
db.Entry(cashMoney).State = EntityState.Modified;
db.SaveChanges();
}
}
catch (Exception)
{
log.Error("Fail database connection\n");
}
}
private static List <CashMoney> Calculate(List <CashMoney> coins, double change, int start = 0)
{
for (int i = start; i < coins.Count; i++)
{
CashMoney coin = coins[i];
if (coin.Quantity > 0 && coin.MoneyValue <= change)
{
double moneyValue = (Double)coin.MoneyValue;
double remainder = change % moneyValue;
if (remainder < change)
{
double s = (change - remainder) / moneyValue;
int quantity = (Int32)coin.Quantity;
int howMany = (Int32)Math.Min(quantity, s);
List <CashMoney> matches = new List <CashMoney>();
matches.Add(new CashMoney(moneyValue, howMany));
double amount = howMany * moneyValue;
double changeLeft = change - amount;
if (changeLeft == 0)
{
return(matches);
}
List <CashMoney> subCalc = Calculate(coins, changeLeft, i + 1);
if (subCalc != null)
{
matches.AddRange(subCalc);
return(matches);
}
}
}
}
return(null);
}