client/mm: CEX balance tracking and auto-rebalancing (#2568)

* multi: Return TxID from Send and add TransactionConfirmations

Send and Withdraw are updated to return a transaction ID. Also,
a TransactionConfirmations function is added to the wallet interface
which allows callers to determine the amount of confirmations a wallet
transaction has.

* client/mm/libxc: Add deposit/withdraw functionality to CEX interface

- Deposit and Withdraw functionality is added to the CEX interface
and is implemented in Binance.
- The CEX interface is updated to take uint32 assetIDs instead of strings
to represent assets.
- The "weth.polygon" and "wbtc.polygon" assets are renamed to be
"eth.polygon" and "btc.polygon". This makes it clear that "btc" and
"btc.polygon" are the same asset, just on different networks.

* client/mm: Tracking of CEX balances

Tracking of CEX balances for each bot is implemented in a similar fashion
to tracking bot balances on the DEX. A `wrappedCEX` is created for each
bot which behaves as if the entire balance of the CEX is the amount that
is allocated for each bot.

* client/mm: Simple arb bot auto-rebalancing

This implements auto-rebalancing in the simple arbitrage strategy. This is
an optional functionality that allows the user to specify a minimum
balance of each asset that should be on both the DEX and the CEX. If the
balance dips below this amount, then either a deposit or withdrawal will
be done to have an equal amount of the asset on both exchanges.

client/asset/btc/btc.go

@@ -4339,6 +4339,17 @@ func (btc *baseWallet) SwapConfirmations(_ context.Context, id dex.Bytes, contra
 	return btc.node.swapConfirmations(txHash, vout, pkScript, startTime)
 }
 
+// TransactionConfirmations gets the number of confirmations for the specified
+// transaction.
+func (btc *baseWallet) TransactionConfirmations(ctx context.Context, txID string) (confs uint32, err error) {
+	txHash, err := chainhash.NewHashFromStr(txID)
+	if err != nil {
+		return 0, fmt.Errorf("error decoding txid %q: %w", txID, err)
+	}
+	_, confs, err = btc.rawWalletTx(txHash)
+	return
+}
+
 // RegFeeConfirmations gets the number of confirmations for the specified output
 // by first checking for a unspent output, and if not found, searching indexed
 // wallet transactions.

client/asset/btc/btc_test.go

@@ -2489,6 +2489,7 @@ func (c *tCoin) ID() dex.Bytes {
 	return make([]byte, 36)
 }
 func (c *tCoin) String() string { return hex.EncodeToString(c.id) }
+func (c *tCoin) TxID() string   { return hex.EncodeToString(c.id) }
 func (c *tCoin) Value() uint64  { return 100 }
 
 func TestReturnCoins(t *testing.T) {

client/asset/btc/types.go

@@ -69,6 +69,11 @@ func (op *Output) String() string {
 	return op.Pt.String()
 }
 
+// TxID is the ID of the transaction used to create the coin.
+func (op *Output) TxID() string {
+	return op.txHash().String()
+}
+
 // txHash returns the pointer of the wire.OutPoint's Hash.
 func (op *Output) txHash() *chainhash.Hash {
 	return &op.Pt.TxHash

client/asset/dcr/dcr.go

@@ -357,6 +357,10 @@ func (op *output) ID() dex.Bytes {
 	return toCoinID(op.txHash(), op.vout())
 }
 
+func (op *output) TxID() string {
+	return op.txHash().String()
+}
+
 // String is a string representation of the coin.
 func (op *output) String() string {
 	return op.pt.String()
@@ -4353,6 +4357,20 @@ func (dcr *ExchangeWallet) SwapConfirmations(ctx context.Context, coinID, contra
 	return confs, spent, err
 }
 
+// TransactionConfirmations gets the number of confirmations for the specified
+// transaction.
+func (dcr *ExchangeWallet) TransactionConfirmations(ctx context.Context, txID string) (confs uint32, err error) {
+	txHash, err := chainhash.NewHashFromStr(txID)
+	if err != nil {
+		return 0, fmt.Errorf("error decoding txid %s: %w", txID, err)
+	}
+	tx, err := dcr.wallet.GetTransaction(ctx, txHash)
+	if err != nil {
+		return 0, err
+	}
+	return uint32(tx.Confirmations), nil
+}
+
 // RegFeeConfirmations gets the number of confirmations for the specified
 // output.
 func (dcr *ExchangeWallet) RegFeeConfirmations(ctx context.Context, coinID dex.Bytes) (confs uint32, err error) {

client/asset/dcr/dcr_test.go

@@ -1065,6 +1065,7 @@ func (c *tCoin) ID() dex.Bytes {
 func (c *tCoin) String() string                                    { return hex.EncodeToString(c.id) }
 func (c *tCoin) Value() uint64                                     { return 100 }
 func (c *tCoin) Confirmations(ctx context.Context) (uint32, error) { return 2, nil }
+func (c *tCoin) TxID() string                                      { return hex.EncodeToString(c.id) }
 
 func TestReturnCoins(t *testing.T) {
 	wallet, node, shutdown := tNewWallet()

client/asset/eth/eth.go

@@ -1408,6 +1408,10 @@ func (c *coin) ID() dex.Bytes {
 	return c.id[:]
 }
 
+func (c *coin) TxID() string {
+	return c.String()
+}
+
 // String is a string representation of the coin.
 func (c *coin) String() string {
 	return c.id.String()
@@ -3346,6 +3350,13 @@ func (eth *baseWallet) swapOrRedemptionFeesPaid(ctx context.Context, coinID, con
 	return dexeth.WeiToGwei(bigFees), secretHashes, nil
 }
 
+// TransactionConfirmations gets the number of confirmations for the specified
+// transaction.
+func (eth *baseWallet) TransactionConfirmations(ctx context.Context, txID string) (confs uint32, err error) {
+	txHash := common.HexToHash(txID)
+	return eth.node.transactionConfirmations(ctx, txHash)
+}
+
 // RegFeeConfirmations gets the number of confirmations for the specified
 // transaction.
 func (eth *baseWallet) RegFeeConfirmations(ctx context.Context, coinID dex.Bytes) (confs uint32, err error) {

client/asset/eth/eth_test.go

@@ -1483,6 +1483,9 @@ func (*badCoin) ID() dex.Bytes {
 func (*badCoin) String() string {
 	return "abc"
 }
+func (*badCoin) TxID() string {
+	return "abc"
+}
 func (b *badCoin) Value() uint64 {
 	return uint64(*b)
 }

client/asset/eth/fundingcoin.go

@@ -32,6 +32,10 @@ func (c *fundingCoin) ID() dex.Bytes {
 	return []byte(c.addr.String())
 }
 
+func (c *fundingCoin) TxID() string {
+	return ""
+}
+
 // Value returns the value reserved in the funding coin.
 func (c *fundingCoin) Value() uint64 {
 	return c.amt
@@ -89,6 +93,10 @@ func (c *tokenFundingCoin) ID() dex.Bytes {
 	return []byte(c.addr.String())
 }
 
+func (c *tokenFundingCoin) TxID() string {
+	return ""
+}
+
 // ID creates a byte slice that can be decoded with DecodeCoinID.
 func (c *tokenFundingCoin) RecoveryID() dex.Bytes {
 	b := make([]byte, tokenFundingCoinIDSize)

client/asset/interface.go

@@ -526,6 +526,10 @@ type Wallet interface {
 	// payment. This method need not be supported by all assets. Those assets
 	// which do no support DEX registration fees will return an ErrUnsupported.
 	RegFeeConfirmations(ctx context.Context, coinID dex.Bytes) (confs uint32, err error)
+	// TransactionConfirmations gets the number of confirmations for the
+	// specified transaction. If the wallet does not know about the
+	// transaction, asset.CoinNotFoundError is returned.
+	TransactionConfirmations(ctx context.Context, txID string) (confs uint32, err error)
 	// Send sends the exact value to the specified address. This is different
 	// from Withdraw, which subtracts the tx fees from the amount sent.
 	Send(address string, value, feeRate uint64) (Coin, error)
@@ -1217,6 +1221,8 @@ type Coin interface {
 	String() string
 	// Value is the available quantity, in atoms/satoshi.
 	Value() uint64
+	// TxID is the ID of the transaction that created the coin.
+	TxID() string
 }
 
 type RecoveryCoin interface {

client/asset/zec/zec.go

@@ -2123,6 +2123,21 @@ func (w *zecWallet) Send(address string, value, feeRate uint64) (asset.Coin, err
 	return btc.NewOutput(txHash, vout, sent), nil
 }
 
+// TransactionConfirmations gets the number of confirmations for the specified
+// transaction.
+func (w *zecWallet) TransactionConfirmations(ctx context.Context, txID string) (confs uint32, err error) {
+	txHash, err := chainhash.NewHashFromStr(txID)
+	if err != nil {
+		return 0, fmt.Errorf("error decoding txid %q: %w", txID, err)
+	}
+	res, err := getWalletTransaction(w, txHash)
+	if err != nil {
+		return 0, err
+	}
+
+	return uint32(res.Confirmations), nil
+}
+
 // send the value to the address, with the given fee rate. If subtract is true,
 // the fees will be subtracted from the value. If false, the fees are in
 // addition to the value. feeRate is in units of sats/byte.