public TransactionBuildingContext CreateMemento()
{
var memento = new TransactionBuildingContext(Builder);
memento.RestoreMemento(this);
return(memento);
}
Money SetChange(TransactionBuildingContext ctx)
{
if (ctx.ChangeAmount == Money.Zero)
{
return(Money.Zero);
}
ctx.Transaction.AddOutput(new TxOut(ctx.ChangeAmount, ctx.Group.ChangeScript[(int)ChangeType.Uncolored]));
return(ctx.ChangeAmount);
}
private IEnumerable <ICoin> BuildTransaction(
TransactionBuildingContext ctx,
BuilderGroup group,
IEnumerable <Builder> builders,
IEnumerable <ICoin> coins)
{
var originalCtx = ctx.CreateMemento();
var target = builders.Concat(ctx.AdditionalBuilders).Select(b => b(ctx)).Sum();
if (ctx.CoverOnly != null)
{
target = ctx.CoverOnly + ctx.ChangeAmount;
}
var selection = CoinSelector.Select(coins, target);
if (selection == null)
{
throw new NotEnoughFundsException("Not enough fund to cover the target");
}
var total = selection.Select(s => s.Amount).Sum();
var change = total - target;
if (change < Money.Zero)
{
throw new NotEnoughFundsException("Not enough fund to cover the target");
}
if (change > ctx.Dust)
{
if (group.ChangeScript[(int)ctx.ChangeType] == null)
{
throw new InvalidOperationException("A change address should be specified (" + ctx.ChangeType + ")");
}
ctx.RestoreMemento(originalCtx);
ctx.ChangeAmount = change;
try
{
return(BuildTransaction(ctx, group, builders, coins));
}
finally
{
ctx.ChangeAmount = Money.Zero;
}
}
foreach (var coin in selection)
{
var input = ctx.Transaction.AddInput(new TxIn(coin.Outpoint));
if (_LockTime != null && _LockTime.HasValue && !ctx.NonFinalSequenceSet)
{
input.Sequence = 0;
ctx.NonFinalSequenceSet = true;
}
}
return(selection);
}
Money SetColoredChange(TransactionBuildingContext ctx)
{
if (ctx.ChangeAmount == Money.Zero)
{
return(Money.Zero);
}
var marker = ctx.GetColorMarker(false);
var txout = ctx.Transaction.AddOutput(new TxOut(ColoredDust, ctx.Group.ChangeScript[(int)ChangeType.Colored]));
marker.SetQuantity(ctx.Transaction.Outputs.Count - 2, ctx.ChangeAmount);
ctx.AdditionalFees += ColoredDust;
return(ctx.ChangeAmount);
}
public Transaction BuildTransaction(bool sign, SigHash sigHash)
{
TransactionBuildingContext ctx = new TransactionBuildingContext(this);
if (_CompletedTransaction != null)
{
ctx.Transaction = _CompletedTransaction;
}
if (_LockTime != null && _LockTime.HasValue)
{
ctx.Transaction.LockTime = _LockTime.Value;
}
foreach (var group in _BuilderGroups)
{
ctx.Group = group;
ctx.AdditionalBuilders.Clear();
ctx.AdditionalFees = Money.Zero;
ctx.ChangeType = ChangeType.Colored;
foreach (var builder in group.IssuanceBuilders)
{
builder(ctx);
}
var buildersByAsset = group.BuildersByAsset.ToList();
foreach (var builders in buildersByAsset)
{
var coins = group.Coins.Values.OfType <ColoredCoin>().Where(c => c.Asset.Id == builders.Key).OfType <ICoin>();
ctx.Dust = Money.Zero;
ctx.CoverOnly = null;
var btcSpent = BuildTransaction(ctx, group, builders.Value, coins)
.OfType <IColoredCoin>().Select(c => c.Bearer.Amount).Sum();
ctx.AdditionalFees -= btcSpent;
}
ctx.AdditionalBuilders.Add(_ => _.AdditionalFees);
ctx.Dust = Money.Dust;
ctx.CoverOnly = group.CoverOnly;
ctx.ChangeType = ChangeType.Uncolored;
BuildTransaction(ctx, group, group.Builders, group.Coins.Values.OfType <Coin>());
}
ctx.Finish();
if (sign)
{
SignTransactionInPlace(ctx.Transaction, sigHash);
}
return(ctx.Transaction);
}
public void RestoreMemento(TransactionBuildingContext memento)
{
_Marker = memento._Marker == null ? null : new ColorMarker(memento._Marker.GetScript());
Transaction = memento.Transaction.Clone();
AdditionalFees = memento.AdditionalFees;
}
private IEnumerable<ICoin> BuildTransaction(
TransactionBuildingContext ctx,
BuilderGroup group,
IEnumerable<Builder> builders,
IEnumerable<ICoin> coins,
IMoney zero)
{
var originalCtx = ctx.CreateMemento();
var target = builders.Concat(ctx.AdditionalBuilders).Select(b => b(ctx)).Sum(zero);
if(ctx.CoverOnly != null)
{
target = ctx.CoverOnly.Add(ctx.ChangeAmount);
}
var unconsumed = coins.Where(c => ctx.ConsumedCoins.All(cc => cc.Outpoint != c.Outpoint));
var selection = CoinSelector.Select(unconsumed, target);
if(selection == null)
throw new NotEnoughFundsException("Not enough fund to cover the target",
group.Name,
target.Sub(unconsumed.Select(u => u.Amount).Sum(zero))
);
var total = selection.Select(s => s.Amount).Sum(zero);
var change = total.Sub(target);
if(change.CompareTo(zero) == -1)
throw new NotEnoughFundsException("Not enough fund to cover the target",
group.Name,
change.Negate()
);
if(change.CompareTo(ctx.Dust) == 1)
{
var changeScript = group.ChangeScript[(int)ctx.ChangeType];
if(changeScript == null)
throw new InvalidOperationException("A change address should be specified (" + ctx.ChangeType + ")");
if(!(ctx.Dust is Money) || change.CompareTo(GetDust(changeScript)) == 1)
{
ctx.RestoreMemento(originalCtx);
ctx.ChangeAmount = change;
try
{
return BuildTransaction(ctx, group, builders, coins, zero);
}
finally
{
ctx.ChangeAmount = zero;
}
}
}
foreach(var coin in selection)
{
ctx.ConsumedCoins.Add(coin);
var input = ctx.Transaction.Inputs.FirstOrDefault(i => i.PrevOut == coin.Outpoint);
if(input == null)
input = ctx.Transaction.AddInput(new TxIn(coin.Outpoint));
if(_LockTime != null && !ctx.NonFinalSequenceSet)
{
input.Sequence = 0;
ctx.NonFinalSequenceSet = true;
}
}
return selection;
}
public Money Build(TransactionBuildingContext ctx)
{
ctx.Transaction.Outputs.Add(_TxOut);
return(_TxOut.Value);
}
/// <summary>
/// Build the transaction
/// </summary>
/// <param name="sign">True if signs all inputs with the available keys</param>
/// <param name="sigHash">The type of signature</param>
/// <returns>The transaction</returns>
/// <exception cref="NBitcoin.NotEnoughFundsException">Not enough funds are available</exception>
public Transaction BuildTransaction(bool sign, SigHash sigHash)
{
TransactionBuildingContext ctx = new TransactionBuildingContext(this);
if(_CompletedTransaction != null)
ctx.Transaction = _CompletedTransaction.Clone();
if(_LockTime != null)
ctx.Transaction.LockTime = _LockTime.Value;
foreach(var group in _BuilderGroups)
{
ctx.Group = group;
ctx.AdditionalBuilders.Clear();
ctx.AdditionalFees = Money.Zero;
ctx.ChangeType = ChangeType.Colored;
foreach(var builder in group.IssuanceBuilders)
builder(ctx);
var buildersByAsset = group.BuildersByAsset.ToList();
foreach(var builders in buildersByAsset)
{
var coins = group.Coins.Values.OfType<ColoredCoin>().Where(c => c.Amount.Id == builders.Key);
ctx.Dust = new AssetMoney(builders.Key);
ctx.CoverOnly = null;
ctx.ChangeAmount = new AssetMoney(builders.Key);
var btcSpent = BuildTransaction(ctx, group, builders.Value, coins, new AssetMoney(builders.Key))
.OfType<IColoredCoin>().Select(c => c.Bearer.Amount).Sum();
ctx.AdditionalFees -= btcSpent;
}
ctx.AdditionalBuilders.Add(_ => _.AdditionalFees);
ctx.Dust = GetDust();
ctx.ChangeAmount = Money.Zero;
ctx.CoverOnly = group.CoverOnly;
ctx.ChangeType = ChangeType.Uncolored;
BuildTransaction(ctx, group, group.Builders, group.Coins.Values.OfType<Coin>(), Money.Zero);
}
ctx.Finish();
if(sign)
{
SignTransactionInPlace(ctx.Transaction, sigHash);
}
return ctx.Transaction;
}
IMoney SetColoredChange(TransactionBuildingContext ctx)
{
var changeAmount = (AssetMoney)ctx.ChangeAmount;
if(changeAmount.Quantity == 0)
return changeAmount;
var marker = ctx.GetColorMarker(false);
var script = ctx.Group.ChangeScript[(int)ChangeType.Colored];
var txout = ctx.Transaction.AddOutput(new TxOut(GetDust(script), script));
marker.SetQuantity(ctx.Transaction.Outputs.Count - 2, changeAmount.Quantity);
ctx.AdditionalFees += txout.Value;
return changeAmount;
}
IMoney SetChange(TransactionBuildingContext ctx)
{
var changeAmount = (Money)ctx.ChangeAmount;
if(changeAmount.Satoshi == 0)
return Money.Zero;
ctx.Transaction.AddOutput(new TxOut(changeAmount, ctx.Group.ChangeScript[(int)ChangeType.Uncolored]));
return changeAmount;
}
public void RestoreMemento(TransactionBuildingContext memento)
{
_Marker = memento._Marker == null ? null : new ColorMarker(memento._Marker.GetScript());
Transaction = memento.Transaction.Clone();
AdditionalFees = memento.AdditionalFees;
}
public TransactionBuildingContext CreateMemento()
{
var memento = new TransactionBuildingContext(Builder);
memento.RestoreMemento(this);
return memento;
}
