public async Task <OperationResult> Convert(int userId, decimal amount, string fromCurrency,
string toCurrency)
{
var fromWallet = await walletManager.GetUserWallet(userId, fromCurrency);
if (fromWallet == null)
{
return(new OperationResult(false, Constants.WalletNotExistsMsg));
}
if (fromWallet.Amount < amount)
{
return(new OperationResult(false, Constants.WalletHasNotEnoughMoneyMsg));
}
var toWallet = await walletManager.GetUserWallet(userId, toCurrency)
?? await walletManager.CreateUserWallet(userId, toCurrency, 0);
var currencyRate = await currencyManager.GetCurrencyRate(fromCurrency, toCurrency);
if (!currencyRate.HasValue)
{
return(new OperationResult(false, Constants.CurrencyNotSupported));
}
fromWallet.Amount -= amount;
toWallet.Amount += Decimal.Round(amount / currencyRate.Value, 2, MidpointRounding.ToNegativeInfinity);
await walletManager.UpdateUserWallets(fromWallet, toWallet);
return(new OperationResult(true, String.Empty));
}