input: update all taproot script spends to optionally make the ctrl block

In this commit, we update all the taproot scripts spends to optionally
make the control block. This is useful in cases where we've already
created the control block, or may not have the items needed to construct
it in the first place.

We also add the control block to the sign descriptor itself.

input/witnessgen.go

@@ -515,6 +515,205 @@ func (wt StandardWitnessType) WitnessGenerator(signer Signer,
 		case NestedWitnessKeyHash:
 			return signer.ComputeInputScript(tx, desc)
 
+		case TaprootLocalCommitSpend:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootScriptSpendSignMethod
+
+			// The control block bytes must be set at this point.
+			if desc.ControlBlock == nil {
+				return nil, fmt.Errorf("control block must be " +
+					"set for taproot spend")
+			}
+
+			witness, err := TaprootCommitSpendSuccess(
+				signer, desc, tx, nil,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootRemoteCommitSpend:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootScriptSpendSignMethod
+
+			// The control block bytes must be set at this point.
+			if desc.ControlBlock == nil {
+				return nil, fmt.Errorf("control block must be " +
+					"set for taproot spend")
+			}
+
+			witness, err := TaprootCommitRemoteSpend(
+				signer, desc, tx, nil,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootAnchorSweepSpend:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootKeySpendSignMethod
+
+			// The tap tweak must be set at this point.
+			if desc.TapTweak == nil {
+				return nil, fmt.Errorf("tap tweak must be " +
+					"set for keyspend")
+			}
+
+			witness, err := TaprootAnchorSpend(
+				signer, desc, tx,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootHtlcOfferedTimeoutSecondLevel,
+			TaprootHtlcAcceptedSuccessSecondLevel:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootScriptSpendSignMethod
+
+			// The control block bytes must be set at this point.
+			if desc.ControlBlock == nil {
+				return nil, fmt.Errorf("control block must be " +
+					"set for taproot spend")
+			}
+
+			witness, err := TaprootHtlcSpendSuccess(
+				signer, desc, tx, nil, nil,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootHtlcSecondLevelRevoke:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootKeySpendSignMethod
+
+			// The tap tweak must be set at this point.
+			if desc.TapTweak == nil {
+				return nil, fmt.Errorf("tap tweak must be " +
+					"set for keyspend")
+			}
+
+			witness, err := TaprootHtlcSpendRevoke(
+				signer, desc, tx,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootHtlcOfferedRevoke:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootKeySpendSignMethod
+
+			// The tap tweak must be set at this point.
+			if desc.TapTweak == nil {
+				return nil, fmt.Errorf("tap tweak must be " +
+					"set for keyspend")
+			}
+
+			witness, err := SenderHTLCScriptTaprootRevoke(
+				signer, desc, tx,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootHtlcAcceptedRevoke:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootKeySpendSignMethod
+
+			// The tap tweak must be set at this point.
+			if desc.TapTweak == nil {
+				return nil, fmt.Errorf("tap tweak must be " +
+					"set for keyspend")
+			}
+
+			witness, err := ReceiverHTLCScriptTaprootRevoke(
+				signer, desc, tx,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootHtlcOfferedRemoteTimeout:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootScriptSpendSignMethod
+
+			// The control block bytes must be set at this point.
+			if desc.ControlBlock == nil {
+				return nil, fmt.Errorf("control block must be " +
+					"set for taproot spend")
+			}
+
+			witness, err := ReceiverHTLCScriptTaprootTimeout(
+				signer, desc, tx, -1, nil, nil,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
+		case TaprootCommitmentRevoke:
+			// Ensure that the sign desc has the proper sign method
+			// set, and a valid prev output fetcher.
+			desc.SignMethod = TaprootScriptSpendSignMethod
+
+			// The control block bytes must be set at this point.
+			if desc.ControlBlock == nil {
+				return nil, fmt.Errorf("control block " +
+					"must be set for taproot spend")
+			}
+
+			witness, err := TaprootCommitSpendRevoke(
+				signer, desc, tx, nil,
+			)
+			if err != nil {
+				return nil, err
+			}
+
+			return &Script{
+				Witness: witness,
+			}, nil
+
 		default:
 			return nil, fmt.Errorf("unknown witness type: %v", wt)
 		}