private async Task InitiateSwapAsync(
Swap swap,
CancellationToken cancellationToken = default)
{
Log.Debug("Initiate swap {@swapId}", swap.Id);
var soldCurrency = _account.Currencies.GetByName(swap.SoldCurrency);
if (swap.Secret == null)
{
var secret = _account.Wallet
.GetDeterministicSecret(soldCurrency, swap.TimeStamp);
swap.Secret = secret.SubArray(0, CurrencySwap.DefaultSecretSize);
await UpdateSwapAsync(swap, SwapStateFlags.HasSecret, cancellationToken)
.ConfigureAwait(false);
secret.Clear();
}
if (swap.SecretHash == null)
{
swap.SecretHash = CurrencySwap.CreateSwapSecretHash(swap.Secret);
await UpdateSwapAsync(swap, SwapStateFlags.HasSecretHash, cancellationToken)
.ConfigureAwait(false);
}
var redeemFromWalletAddress = swap.RedeemFromAddress != null
? await _account
.GetAddressAsync(swap.PurchasedCurrency, swap.RedeemFromAddress, cancellationToken)
.ConfigureAwait(false)
: null;
var purchasedCurrency = _account.Currencies.GetByName(swap.PurchasedCurrency);
swap.RewardForRedeem = await RewardForRedeemHelper
.EstimateAsync(
account : _account,
quotesProvider : _quotesProvider,
feeCurrencyQuotesProvider : symbol => _marketDataRepository
?.OrderBookBySymbol(symbol)
?.TopOfBook(),
redeemableCurrency : purchasedCurrency,
redeemFromAddress : redeemFromWalletAddress,
cancellationToken : cancellationToken)
.ConfigureAwait(false);
// select refund address for bitcoin based currency
if (soldCurrency is BitcoinBasedConfig && swap.RefundAddress == null)
{
swap.RefundAddress = (await _account
.GetCurrencyAccount <BitcoinBasedAccount>(soldCurrency.Name)
.GetRefundAddressAsync(cancellationToken)
.ConfigureAwait(false))
?.Address;
}
await UpdateSwapAsync(swap, SwapStateFlags.Empty, cancellationToken)
.ConfigureAwait(false);
_swapClient.SwapInitiateAsync(swap);
}
private async Task <Error> HandleInitiateAsync(
Swap swap,
Swap receivedSwap,
CancellationToken cancellationToken = default)
{
if (DateTime.UtcNow > swap.TimeStamp.ToUniversalTime() + DefaultCredentialsExchangeTimeout)
{
Log.Error("Handle initiate after swap {@swap} timeout", swap.Id);
swap.StateFlags |= SwapStateFlags.IsCanceled;
await UpdateSwapAsync(swap, SwapStateFlags.IsCanceled, cancellationToken)
.ConfigureAwait(false);
return(null); // no error
}
// check secret hash
if (swap.SecretHash != null &&
!swap.SecretHash.SequenceEqual(receivedSwap.SecretHash))
{
return(new Error(Errors.InvalidSecretHash, $"Secret hash does not match the one already received for swap {swap.Id}"));
}
if (receivedSwap.SecretHash == null ||
receivedSwap.SecretHash.Length != CurrencySwap.DefaultSecretHashSize)
{
return(new Error(Errors.InvalidSecretHash, $"Incorrect secret hash length for swap {swap.Id}"));
}
Log.Debug("Secret hash {@hash} successfully received", receivedSwap.SecretHash.ToHexString());
swap.SecretHash = receivedSwap.SecretHash;
await UpdateSwapAsync(swap, SwapStateFlags.HasSecretHash, cancellationToken)
.ConfigureAwait(false);
// check party address
if (receivedSwap.PartyAddress == null)
{
return(new Error(Errors.InvalidWallets, $"Incorrect party address for swap {swap.Id}"));
}
// check party reward for redeem
if (receivedSwap.RewardForRedeem < 0)
{
return(new Error(Errors.InvalidRewardForRedeem, $"Incorrect reward for redeem for swap {swap.Id}"));
}
if (swap.PartyAddress == null)
{
swap.PartyAddress = receivedSwap.PartyAddress;
}
if (swap.PartyRewardForRedeem == 0 && receivedSwap.PartyRewardForRedeem > 0)
{
swap.PartyRewardForRedeem = receivedSwap.PartyRewardForRedeem;
}
if (swap.PartyRefundAddress == null)
{
swap.PartyRefundAddress = receivedSwap.PartyRefundAddress;
}
var redeemFromWalletAddress = swap.RedeemFromAddress != null
? await _account
.GetAddressAsync(swap.PurchasedCurrency, swap.RedeemFromAddress, cancellationToken)
.ConfigureAwait(false)
: null;
var purchasedCurrency = _account.Currencies.GetByName(swap.PurchasedCurrency);
swap.RewardForRedeem = await RewardForRedeemHelper
.EstimateAsync(
account : _account,
quotesProvider : _quotesProvider,
feeCurrencyQuotesProvider : symbol => _marketDataRepository
?.OrderBookBySymbol(symbol)
?.TopOfBook(),
redeemableCurrency : purchasedCurrency,
redeemFromAddress : redeemFromWalletAddress,
cancellationToken : cancellationToken)
.ConfigureAwait(false);
var soldCurrency = _account.Currencies.GetByName(swap.SoldCurrency);
// select refund address for bitcoin based currency
if (soldCurrency is BitcoinBasedConfig && swap.RefundAddress == null)
{
swap.RefundAddress = (await _account
.GetCurrencyAccount <BitcoinBasedAccount>(soldCurrency.Name)
.GetRefundAddressAsync(cancellationToken)
.ConfigureAwait(false))
?.Address;
}
await UpdateSwapAsync(swap, SwapStateFlags.Empty, cancellationToken)
.ConfigureAwait(false);
// send "accept" to other side
_swapClient.SwapAcceptAsync(swap);
await GetCurrencySwap(swap.PurchasedCurrency)
.StartPartyPaymentControlAsync(swap, cancellationToken)
.ConfigureAwait(false);
return(null); // no error
}
public static Task <SwapParams> EstimateSwapParamsAsync(
IFromSource from,
decimal fromAmount,
string redeemFromAddress,
CurrencyConfig fromCurrency,
CurrencyConfig toCurrency,
IAccount account,
IAtomexClient atomexClient,
ISymbolsProvider symbolsProvider,
ICurrencyQuotesProvider quotesProvider,
CancellationToken cancellationToken = default)
{
return(Task.Run(async() =>
{
if (fromCurrency == null)
{
return null;
}
if (toCurrency == null)
{
return null;
}
var redeemFromWalletAddress = redeemFromAddress != null
? await account
.GetAddressAsync(toCurrency.Name, redeemFromAddress, cancellationToken)
.ConfigureAwait(false)
: null;
// estimate redeem fee
var estimatedRedeemFee = await toCurrency
.GetEstimatedRedeemFeeAsync(redeemFromWalletAddress, withRewardForRedeem: false)
.ConfigureAwait(false);
// estimate reward for redeem
var rewardForRedeem = await RewardForRedeemHelper.EstimateAsync(
account: account,
quotesProvider: quotesProvider,
feeCurrencyQuotesProvider: symbol => atomexClient?.GetOrderBook(symbol)?.TopOfBook(),
redeemableCurrency: toCurrency,
redeemFromAddress: redeemFromWalletAddress,
cancellationToken: cancellationToken);
// get amount reserved for active swaps
var reservedForSwapsAmount = await GetAmountReservedForSwapsAsync(
from: from,
account: account,
currency: fromCurrency)
.ConfigureAwait(false);
// estimate maker network fee
var estimatedMakerNetworkFee = await EstimateMakerNetworkFeeAsync(
fromCurrency: fromCurrency,
toCurrency: toCurrency,
account: account,
atomexClient: atomexClient,
symbolsProvider: symbolsProvider,
cancellationToken: cancellationToken)
.ConfigureAwait(false);
var fromCurrencyAccount = account
.GetCurrencyAccount(fromCurrency.Name) as IEstimatable;
// estimate payment fee
var estimatedPaymentFee = await fromCurrencyAccount
.EstimateSwapPaymentFeeAsync(
from: from,
amount: fromAmount,
cancellationToken: cancellationToken)
.ConfigureAwait(false);
// estimate max amount and max fee
var maxAmountEstimation = await fromCurrencyAccount
.EstimateMaxSwapPaymentAmountAsync(
from: from,
reserve: true,
cancellationToken: cancellationToken)
.ConfigureAwait(false);
if (maxAmountEstimation.Error != null)
{
return new SwapParams
{
Amount = 0m,
PaymentFee = estimatedPaymentFee.Value,
RedeemFee = estimatedRedeemFee,
RewardForRedeem = rewardForRedeem,
MakerNetworkFee = estimatedMakerNetworkFee,
ReservedForSwaps = reservedForSwapsAmount,
Error = maxAmountEstimation.Error
};
}
var maxNetAmount = Math.Max(maxAmountEstimation.Amount - reservedForSwapsAmount - estimatedMakerNetworkFee, 0m);
if (maxNetAmount == 0m) // insufficient funds
{
return new SwapParams
{
Amount = 0m,
PaymentFee = maxAmountEstimation.Fee,
RedeemFee = estimatedRedeemFee,
RewardForRedeem = rewardForRedeem,
MakerNetworkFee = estimatedMakerNetworkFee,
ReservedForSwaps = reservedForSwapsAmount,
Error = new Error(
code: Errors.InsufficientFunds,
description: Resources.InsufficientFundsToCoverMakerNetworkFee,
details: string.Format(Resources.InsufficientFundsToCoverMakerNetworkFeeDetails,
estimatedMakerNetworkFee, // required
fromCurrency.Name, // currency code
maxAmountEstimation.Amount - reservedForSwapsAmount)) // available
};
}
if (fromAmount > maxNetAmount) // amount greater than max net amount => use max amount params
{
return new SwapParams
{
Amount = Math.Max(maxNetAmount, 0m),
PaymentFee = maxAmountEstimation.Fee,
RedeemFee = estimatedRedeemFee,
RewardForRedeem = rewardForRedeem,
MakerNetworkFee = estimatedMakerNetworkFee,
ReservedForSwaps = reservedForSwapsAmount,
Error = new Error(
code: Errors.InsufficientFunds,
description: Resources.InsufficientFunds,
details: string.Format(Resources.InsufficientFundsToSendAmountDetails,
fromAmount, // required
fromCurrency.Name, // currency code
maxNetAmount)) // available
};
}
return new SwapParams
{
Amount = fromAmount,
PaymentFee = estimatedPaymentFee.Value,
RedeemFee = estimatedRedeemFee,
RewardForRedeem = rewardForRedeem,
MakerNetworkFee = estimatedMakerNetworkFee,
ReservedForSwaps = reservedForSwapsAmount,
Error = null
};
}, cancellationToken));
}