public double CalculateForeignCurrencyAmount(CurrencyExchangeDirection direction, double localCurrencyAmount, double sellValue, double buyValue)
{
double effectiveRate = 0;
if (direction == CurrencyExchangeDirection.BuyForeign)
{
//Client if buying from the market, it will pay the value the market is selling
effectiveRate = sellValue;
}
else if (direction == CurrencyExchangeDirection.SellForeign)
{
//Client is selling to the market, it will receive the value the market is buying
effectiveRate = 1 / buyValue;
}
else
{
throw new NotImplementedException("Invalid exchange direction!");
}
double ForeignCurrencyAmount = localCurrencyAmount / effectiveRate;
return(ForeignCurrencyAmount);
}
public void CalculateForeignCurrencyAmount_Should_Take_Direction_And_Different_Rates_Into_Consideration(CurrencyExchangeDirection direction, double localCurrencyAmount, double sellValue, double buyValue, double expectedAmount)
{
//Arrange
Mock <ICurrencyExchangeTransactionsRepository> mockCcyExchgTransaction = new Mock <ICurrencyExchangeTransactionsRepository>();
Mock <IRatesRepository> mockRatesRepo = new Mock <IRatesRepository>();
CurrencyExchangeService currencyExchangeService = new CurrencyExchangeService(mockCcyExchgTransaction.Object, mockRatesRepo.Object);
//Act
double actualAmount = currencyExchangeService.CalculateForeignCurrencyAmount(direction, localCurrencyAmount, sellValue, buyValue);
//Assert
Assert.Equal(Math.Round(expectedAmount, 5), Math.Round(actualAmount, 5));
}
