Change representation of taproot trees & Internal fixes (#384)

* migrate descriptors --> tapscripts

* fix covenantless

* dynamic boarding exit delay

* remove duplicates in tree and bitcointree

* agnostic signatures validation

* revert GetInfo change

* renaming VtxoScript var

* Agnostic script server (#6)

* Hotfix: Prevent ZMQ-based bitcoin wallet to panic  (#383)

* Hotfix bct embedded wallet w/ ZMQ

* Fixes

* Rename vtxo is_oor to is_pending (#385)

* Rename vtxo is_oor > is_pending

* Clean swaggers

* Revert changes to client and sdk

* descriptor in oneof

* support CHECKSIG_ADD in MultisigClosure

* use right witness size in OOR tx fee estimation

* Revert changes

---------

Co-authored-by: Pietralberto Mazza <18440657+altafan@users.noreply.github.com>

server/internal/core/application/covenant.go

@@ -9,7 +9,6 @@ import (
 	"time"
 
 	"github.com/ark-network/ark/common"
-	"github.com/ark-network/ark/common/descriptor"
 	"github.com/ark-network/ark/common/note"
 	"github.com/ark-network/ark/common/tree"
 	"github.com/ark-network/ark/server/internal/core/domain"
@@ -149,29 +148,30 @@ func (s *covenantService) Stop() {
 	close(s.eventsCh)
 }
 
-func (s *covenantService) GetBoardingAddress(ctx context.Context, userPubkey *secp256k1.PublicKey) (string, string, error) {
-	vtxoScript := &tree.DefaultVtxoScript{
-		Asp:       s.pubkey,
-		Owner:     userPubkey,
-		ExitDelay: uint(s.boardingExitDelay),
-	}
+func (s *covenantService) GetBoardingAddress(ctx context.Context, userPubkey *secp256k1.PublicKey) (string, []string, error) {
+	vtxoScript := tree.NewDefaultVtxoScript(userPubkey, s.pubkey, uint(s.boardingExitDelay))
 
 	tapKey, _, err := vtxoScript.TapTree()
 	if err != nil {
-		return "", "", fmt.Errorf("failed to get taproot key: %s", err)
+		return "", nil, fmt.Errorf("failed to get taproot key: %s", err)
 	}
 
 	p2tr, err := payment.FromTweakedKey(tapKey, s.onchainNetwork(), nil)
 	if err != nil {
-		return "", "", err
+		return "", nil, err
 	}
 
 	addr, err := p2tr.TaprootAddress()
 	if err != nil {
-		return "", "", err
+		return "", nil, err
 	}
 
-	return addr, vtxoScript.ToDescriptor(), nil
+	scripts, err := vtxoScript.Encode()
+	if err != nil {
+		return "", nil, err
+	}
+
+	return addr, scripts, nil
 }
 
 func (s *covenantService) SpendNotes(_ context.Context, _ []note.Note) (string, error) {
@@ -211,8 +211,18 @@ func (s *covenantService) SpendVtxos(ctx context.Context, inputs []ports.Input)
 					return "", fmt.Errorf("tx %s not confirmed", input.Txid)
 				}
 
+				vtxoScript, err := tree.ParseVtxoScript(input.Tapscripts)
+				if err != nil {
+					return "", fmt.Errorf("failed to parse boarding descriptor: %s", err)
+				}
+
+				exitDelay, err := vtxoScript.SmallestExitDelay()
+				if err != nil {
+					return "", fmt.Errorf("failed to get exit delay: %s", err)
+				}
+
 				// if the exit path is available, forbid registering the boarding utxo
-				if blocktime+int64(s.boardingExitDelay) < now {
+				if blocktime+int64(exitDelay) < now {
 					return "", fmt.Errorf("tx %s expired", input.Txid)
 				}
 
@@ -242,7 +252,7 @@ func (s *covenantService) SpendVtxos(ctx context.Context, inputs []ports.Input)
 			return "", fmt.Errorf("input %s:%d already swept", vtxo.Txid, vtxo.VOut)
 		}
 
-		vtxoScript, err := tree.ParseVtxoScript(input.Descriptor)
+		vtxoScript, err := tree.ParseVtxoScript(input.Tapscripts)
 		if err != nil {
 			return "", fmt.Errorf("failed to parse boarding descriptor: %s", err)
 		}
@@ -290,7 +300,7 @@ func (s *covenantService) newBoardingInput(tx *transaction.Transaction, input po
 		return nil, fmt.Errorf("failed to parse value: %s", err)
 	}
 
-	boardingScript, err := tree.ParseVtxoScript(input.Descriptor)
+	boardingScript, err := tree.ParseVtxoScript(input.Tapscripts)
 	if err != nil {
 		return nil, fmt.Errorf("failed to parse boarding descriptor: %s", err)
 	}
@@ -309,16 +319,8 @@ func (s *covenantService) newBoardingInput(tx *transaction.Transaction, input po
 		return nil, fmt.Errorf("descriptor does not match script in transaction output")
 	}
 
-	if defaultVtxoScript, ok := boardingScript.(*tree.DefaultVtxoScript); ok {
-		if !bytes.Equal(schnorr.SerializePubKey(defaultVtxoScript.Asp), schnorr.SerializePubKey(s.pubkey)) {
-			return nil, fmt.Errorf("invalid boarding descriptor, ASP mismatch")
-		}
-
-		if defaultVtxoScript.ExitDelay != uint(s.boardingExitDelay) {
-			return nil, fmt.Errorf("invalid boarding descriptor, timeout mismatch")
-		}
-	} else {
-		return nil, fmt.Errorf("only default vtxo script is supported for boarding")
+	if err := boardingScript.Validate(s.pubkey, uint(s.unilateralExitDelay)); err != nil {
+		return nil, err
 	}
 
 	return &ports.BoardingInput{
@@ -430,15 +432,7 @@ func (s *covenantService) GetInfo(ctx context.Context) (*ServiceInfo, error) {
 		RoundInterval:       s.roundInterval,
 		Network:             s.network.Name,
 		Dust:                dust,
-		BoardingDescriptorTemplate: fmt.Sprintf(
-			descriptor.DefaultVtxoDescriptorTemplate,
-			hex.EncodeToString(tree.UnspendableKey().SerializeCompressed()),
-			"USER",
-			hex.EncodeToString(schnorr.SerializePubKey(s.pubkey)),
-			s.boardingExitDelay,
-			"USER",
-		),
-		ForfeitAddress: forfeitAddress,
+		ForfeitAddress:      forfeitAddress,
 	}, nil
 }
 
@@ -852,6 +846,7 @@ func (s *covenantService) reactToFraud(ctx context.Context, vtxo domain.Vtxo, mu
 
 	forfeitTxid, err := s.wallet.BroadcastTransaction(ctx, forfeitTxHex)
 	if err != nil {
+		log.Debug(forfeitTxHex)
 		return fmt.Errorf("failed to broadcast forfeit tx: %s", err)
 	}