Rename folders (#97)

* Rename arkd folder & drop cli

* Rename ark cli folder & update docs

* Update readme

* Fix

* scripts: add build-all

* Add target to build cli for all platforms

* Update build scripts

---------

Co-authored-by: tiero <3596602+tiero@users.noreply.github.com>

client/unilateral_redeem.go

@@ -0,0 +1,185 @@
+package main
+
+import (
+	"fmt"
+
+	"github.com/ark-network/ark/common/tree"
+	"github.com/btcsuite/btcd/btcec/v2/schnorr"
+	"github.com/decred/dcrd/dcrec/secp256k1/v4"
+	"github.com/urfave/cli/v2"
+	"github.com/vulpemventures/go-elements/psetv2"
+	"github.com/vulpemventures/go-elements/taproot"
+)
+
+type RedeemBranch interface {
+	// UpdatePath checks for transactions of the branch onchain and updates the branch accordingly
+	UpdatePath() error
+	// Redeem will sign the branch of the tree and return the associated signed pset + the vtxo input
+	RedeemPath() ([]string, error)
+	// AddInput adds the vtxo input created by the branch
+	AddVtxoInput(updater *psetv2.Updater) error
+}
+
+type redeemBranch struct {
+	vtxo         *vtxo
+	branch       []*psetv2.Pset
+	internalKey  *secp256k1.PublicKey
+	sweepClosure *taproot.TapElementsLeaf
+}
+
+func newRedeemBranch(ctx *cli.Context, congestionTree tree.CongestionTree, vtxo vtxo) (RedeemBranch, error) {
+	sweepClosure, _, err := findSweepClosure(congestionTree)
+	if err != nil {
+		return nil, err
+	}
+
+	nodes, err := congestionTree.Branch(vtxo.txid)
+	if err != nil {
+		return nil, err
+	}
+
+	branch := make([]*psetv2.Pset, 0, len(nodes))
+	for _, node := range nodes {
+		pset, err := psetv2.NewPsetFromBase64(node.Tx)
+		if err != nil {
+			return nil, err
+		}
+		branch = append(branch, pset)
+	}
+
+	xOnlyKey := branch[0].Inputs[0].TapInternalKey
+	internalKey, err := schnorr.ParsePubKey(xOnlyKey)
+	if err != nil {
+		return nil, err
+	}
+
+	return &redeemBranch{
+		vtxo:         &vtxo,
+		branch:       branch,
+		internalKey:  internalKey,
+		sweepClosure: sweepClosure,
+	}, nil
+}
+
+// UpdatePath checks for transactions of the branch onchain and updates the branch accordingly
+func (r *redeemBranch) UpdatePath() error {
+	for i := len(r.branch) - 1; i >= 0; i-- {
+		pset := r.branch[i]
+		unsignedTx, err := pset.UnsignedTx()
+		if err != nil {
+			return err
+		}
+
+		txHash := unsignedTx.TxHash().String()
+
+		_, err = getTxHex(txHash)
+		if err != nil {
+			continue
+		}
+
+		// if no error, the tx exists onchain, so we can remove it (+ the parents) from the branch
+		if i == len(r.branch)-1 {
+			r.branch = []*psetv2.Pset{}
+		} else {
+			r.branch = r.branch[i+1:]
+		}
+
+		break
+	}
+
+	return nil
+}
+
+// RedeemPath returns the list of transactions to broadcast in order to access the vtxo output
+func (r *redeemBranch) RedeemPath() ([]string, error) {
+	transactions := make([]string, 0, len(r.branch))
+
+	for _, pset := range r.branch {
+		for i, input := range pset.Inputs {
+			if len(input.TapLeafScript) == 0 {
+				return nil, fmt.Errorf("tap leaf script not found on input #%d", i)
+			}
+
+			for _, leaf := range input.TapLeafScript {
+				isSweep, _, _, err := tree.DecodeSweepScript(leaf.Script)
+				if err != nil {
+					return nil, err
+				}
+
+				if isSweep {
+					continue
+				}
+
+				controlBlock, err := leaf.ControlBlock.ToBytes()
+				if err != nil {
+					return nil, err
+				}
+
+				unsignedTx, err := pset.UnsignedTx()
+				if err != nil {
+					return nil, err
+				}
+
+				unsignedTx.Inputs[i].Witness = [][]byte{
+					leaf.Script,
+					controlBlock[:],
+				}
+
+				hex, err := unsignedTx.ToHex()
+				if err != nil {
+					return nil, err
+				}
+				transactions = append(transactions, hex)
+
+				break
+			}
+
+		}
+
+	}
+
+	return transactions, nil
+}
+
+// AddVtxoInput is a wrapper around psetv2.Updater adding a taproot input letting to spend the vtxo output
+func (r *redeemBranch) AddVtxoInput(updater *psetv2.Updater) error {
+	walletPubkey, err := getWalletPublicKey()
+	if err != nil {
+		return err
+	}
+
+	nextInputIndex := len(updater.Pset.Inputs)
+	if err := updater.AddInputs([]psetv2.InputArgs{
+		{
+			Txid:    r.vtxo.txid,
+			TxIndex: r.vtxo.vout,
+		},
+	}); err != nil {
+		return err
+	}
+
+	// add taproot tree letting to spend the vtxo
+	checksigLeaf, err := tree.VtxoScript(walletPubkey)
+	if err != nil {
+		return nil
+	}
+
+	vtxoTaprootTree := taproot.AssembleTaprootScriptTree(
+		*checksigLeaf,
+		*r.sweepClosure,
+	)
+
+	proofIndex := vtxoTaprootTree.LeafProofIndex[checksigLeaf.TapHash()]
+
+	if err := updater.AddInTapLeafScript(
+		nextInputIndex,
+		psetv2.NewTapLeafScript(
+			vtxoTaprootTree.LeafMerkleProofs[proofIndex],
+			r.internalKey,
+		),
+	); err != nil {
+		return err
+	}
+
+	return nil
+}