public RatesCalculationResult CalculateResult(Currency baseCurrency, Currency[] currencies, decimal amount, List<Rate> rates)
{
var bestResult = new RatesCalculationResult {Currency = baseCurrency, MaxAmount = amount};
foreach (var currency in currencies)
{
var currentResult = CalculateResultByCurrency(rates, currency, amount);
if (currentResult.MaxAmount > bestResult.MaxAmount)
{
bestResult = currentResult;
}
}
return bestResult;
}
public RatesCalculationResult CalculateResultByCurrency(List<Rate> rates, Currency currency, decimal amount)
{
var bestResult = new RatesCalculationResult { Currency = currency, MaxAmount = 0 };
for (var startDateIndex = 0; startDateIndex < rates.Count - 1; startDateIndex++)
{
var startDateRate = rates[startDateIndex].Rates[currency];
for (var endDateIndex = startDateIndex + 1; endDateIndex < rates.Count; endDateIndex++)
{
var endDateRate = rates[endDateIndex].Rates[currency];
var currentAmount = amount*startDateRate/endDateRate -
rates[endDateIndex].Date.Subtract(rates[startDateIndex].Date).Days;
if (currentAmount > bestResult.MaxAmount)
{
bestResult.MaxAmount = currentAmount;
bestResult.StartDate = rates[startDateIndex].Date;
bestResult.EndDate = rates[endDateIndex].Date;
}
}
}
return bestResult;
}
