Update project structure and build process

recovery_tool/recovery_tool.go

@@ -0,0 +1,144 @@
+package main
+
+import (
+	"bytes"
+	"encoding/hex"
+
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/btcsuite/btcd/wire"
+	"github.com/btcsuite/btcutil"
+
+	"github.com/muun/libwallet"
+	"github.com/muun/libwallet/btcsuitew/txscriptw"
+	"github.com/muun/recovery/scanner"
+)
+
+func buildSweepTx(utxos []*scanner.Utxo, sweepAddress btcutil.Address, fee int64) ([]byte, error) {
+
+	tx := wire.NewMsgTx(2)
+	value := int64(0)
+
+	for _, utxo := range utxos {
+		chainHash, err := chainhash.NewHashFromStr(utxo.TxID)
+		if err != nil {
+			return nil, err
+		}
+
+		outpoint := wire.OutPoint{
+			Hash:  *chainHash,
+			Index: uint32(utxo.OutputIndex),
+		}
+
+		tx.AddTxIn(wire.NewTxIn(&outpoint, []byte{}, [][]byte{}))
+		value += utxo.Amount
+	}
+
+	value -= fee
+
+	script, err := txscriptw.PayToAddrScript(sweepAddress)
+	if err != nil {
+		return nil, err
+	}
+	tx.AddTxOut(wire.NewTxOut(value, script))
+
+	writer := &bytes.Buffer{}
+	err = tx.Serialize(writer)
+	if err != nil {
+		return nil, err
+	}
+
+	if fee != 0 {
+		readConfirmation(value, fee, sweepAddress.String())
+	}
+
+	return writer.Bytes(), nil
+}
+
+func buildSignedTx(utxos []*scanner.Utxo, sweepTx []byte, userKey *libwallet.HDPrivateKey,
+	muunKey *libwallet.HDPrivateKey) (*wire.MsgTx, error) {
+
+	inputList := &libwallet.InputList{}
+	for _, utxo := range utxos {
+		inputList.Add(&input{
+			utxo,
+			[]byte{},
+		})
+	}
+
+	nonces := libwallet.GenerateMusigNonces(len(utxos))
+	pstx, err := libwallet.NewPartiallySignedTransaction(inputList, sweepTx, nonces)
+	if err != nil {
+		return nil, err
+	}
+
+	signedTx, err := pstx.FullySign(userKey, muunKey)
+	if err != nil {
+		return nil, err
+	}
+
+	wireTx := wire.NewMsgTx(0)
+	wireTx.BtcDecode(bytes.NewReader(signedTx.Bytes), 0, wire.WitnessEncoding)
+	return wireTx, nil
+}
+
+// input is a minimal type that implements libwallet.Input
+type input struct {
+	utxo          *scanner.Utxo
+	muunSignature []byte
+}
+
+func (i *input) OutPoint() libwallet.Outpoint {
+	return &outpoint{utxo: i.utxo}
+}
+
+func (i *input) Address() libwallet.MuunAddress {
+	return i.utxo.Address
+}
+
+func (i *input) UserSignature() []byte {
+	return []byte{}
+}
+
+func (i *input) MuunSignature() []byte {
+	return i.muunSignature
+}
+
+func (i *input) SubmarineSwapV1() libwallet.InputSubmarineSwapV1 {
+	return nil
+}
+
+func (i *input) SubmarineSwapV2() libwallet.InputSubmarineSwapV2 {
+	return nil
+}
+
+func (i *input) IncomingSwap() libwallet.InputIncomingSwap {
+	return nil
+}
+
+func (i *input) MuunPublicNonce() []byte {
+	// Will always be nil in the context of the tool
+	// Look at coinV5.signFirstWith for the reason why.
+	return nil
+}
+
+// outpoint is a minimal type that implements libwallet.Outpoint
+type outpoint struct {
+	utxo *scanner.Utxo
+}
+
+func (o *outpoint) TxId() []byte {
+	raw, err := hex.DecodeString(o.utxo.TxID)
+	if err != nil {
+		panic(err) // we wrote this hex value ourselves, no input from anywhere else
+	}
+
+	return raw
+}
+
+func (o *outpoint) Index() int {
+	return o.utxo.OutputIndex
+}
+
+func (o *outpoint) Amount() int64 {
+	return o.utxo.Amount
+}