improved code readability (base#11)

* Update ecdsa_signer.go

added comments to describe each method and rephrased some variable names for clarity.

* Update signer.go

Provided comments for each function describing their purpose  and made some minor improvements for clarity.

* Update wallet_signer.go

 provided comments for each function describing their purpose in and made some minor improvements for clarity.

signer/ecdsa_signer.go

@@ -10,23 +10,29 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 )
 
+// ecdsaSigner represents an ECDSA signer.
 type ecdsaSigner struct {
 	*ecdsa.PrivateKey
 }
 
+// Address returns the address associated with the ECDSA signer.
 func (s *ecdsaSigner) Address() common.Address {
 	return crypto.PubkeyToAddress(s.PublicKey)
 }
 
+// SignerFn returns a signer function using the ECDSA private key and chain ID.
 func (s *ecdsaSigner) SignerFn(chainID *big.Int) bind.SignerFn {
 	return opcrypto.PrivateKeySignerFn(s.PrivateKey, chainID)
 }
 
+// SignData signs the given data using the ECDSA private key.
 func (s *ecdsaSigner) SignData(data []byte) ([]byte, error) {
 	sig, err := crypto.Sign(crypto.Keccak256(data), s.PrivateKey)
 	if err != nil {
 		return nil, err
 	}
+	// Adjust the recovery ID for Ethereum compatibility
 	sig[crypto.RecoveryIDOffset] += 27
-	return sig, err
+	return sig, nil
 }
+

signer/signer.go

@@ -11,12 +11,14 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 )
 
+// Signer defines the interface for interacting with different types of signers.
 type Signer interface {
-	Address() common.Address
-	SignerFn(chainID *big.Int) bind.SignerFn
-	SignData([]byte) ([]byte, error)
+	Address() common.Address        // Address returns the Ethereum address associated with the signer.
+	SignerFn(chainID *big.Int) bind.SignerFn // SignerFn returns a signer function used for transaction signing.
+	SignData([]byte) ([]byte, error) // SignData signs the given data using the signer's private key.
 }
 
+// CreateSigner creates a signer based on the provided private key, mnemonic, or hardware wallet.
 func CreateSigner(privateKey, mnemonic, hdPath string) (Signer, error) {
 	if privateKey != "" {
 		key, err := crypto.HexToECDSA(privateKey)
@@ -32,31 +34,31 @@ func CreateSigner(privateKey, mnemonic, hdPath string) (Signer, error) {
 	}
 
 	if mnemonic != "" {
-		key, err := derivePrivateKey(mnemonic, path)
+		key, err := derivePrivateKeyFromMnemonic(mnemonic, path)
 		if err != nil {
 			return nil, fmt.Errorf("error deriving key from mnemonic: %w", err)
 		}
 		return &ecdsaSigner{key}, nil
 	}
 
-	// assume using a ledger
+	// Assume using a hardware wallet (e.g., Ledger)
 	ledgerHub, err := usbwallet.NewLedgerHub()
 	if err != nil {
-		return nil, fmt.Errorf("error starting ledger: %w", err)
+		return nil, fmt.Errorf("error starting Ledger: %w", err)
 	}
 	wallets := ledgerHub.Wallets()
 	if len(wallets) == 0 {
-		return nil, fmt.Errorf("no ledgers found, please connect your ledger")
+		return nil, fmt.Errorf("no Ledger device found, please connect your Ledger")
 	} else if len(wallets) > 1 {
-		return nil, fmt.Errorf("multiple ledgers found, please use one ledger at a time")
+		return nil, fmt.Errorf("multiple Ledger devices found, please use only one at a time")
 	}
 	wallet := wallets[0]
 	if err := wallet.Open(""); err != nil {
-		return nil, fmt.Errorf("error opening ledger: %w", err)
+		return nil, fmt.Errorf("error opening Ledger: %w", err)
 	}
 	account, err := wallet.Derive(path, true)
 	if err != nil {
-		return nil, fmt.Errorf("error deriving ledger account (have you unlocked?): %w", err)
+		return nil, fmt.Errorf("error deriving Ledger account (have you unlocked?): %w", err)
 	}
 	return &walletSigner{
 		wallet:  wallet,

signer/wallet_signer.go

@@ -13,32 +13,38 @@ import (
 	"github.com/tyler-smith/go-bip39"
 )
 
+// walletSigner represents a signer based on a wallet account.
 type walletSigner struct {
 	wallet  accounts.Wallet
 	account accounts.Account
 }
 
+// Address returns the Ethereum address associated with the signer.
 func (s *walletSigner) Address() common.Address {
 	return s.account.Address
 }
 
+// SignerFn returns a signer function used for transaction signing.
 func (s *walletSigner) SignerFn(chainID *big.Int) bind.SignerFn {
 	return func(address common.Address, tx *types.Transaction) (*types.Transaction, error) {
 		return s.wallet.SignTx(s.account, tx, chainID)
 	}
 }
 
+// SignData signs the given data using the signer's private key.
 func (s *walletSigner) SignData(data []byte) ([]byte, error) {
 	return s.wallet.SignData(s.account, accounts.MimetypeTypedData, data)
 }
 
+// derivePrivateKey derives an ECDSA private key from a mnemonic phrase and derivation path.
 func derivePrivateKey(mnemonic string, path accounts.DerivationPath) (*ecdsa.PrivateKey, error) {
 	// Parse the seed string into the master BIP32 key.
 	seed, err := bip39.NewSeedWithErrorChecking(mnemonic, "")
 	if err != nil {
 		return nil, err
 	}
 
+	// Derive the private key based on the derivation path.
 	privKey, err := hdkeychain.NewMaster(seed, fakeNetworkParams{})
 	if err != nil {
 		return nil, err
@@ -51,6 +57,7 @@ func derivePrivateKey(mnemonic string, path accounts.DerivationPath) (*ecdsa.Pri
 		}
 	}
 
+	// Serialize the private key and convert it to an ECDSA private key.
 	rawPrivKey, err := privKey.SerializedPrivKey()
 	if err != nil {
 		return nil, err
@@ -59,6 +66,7 @@ func derivePrivateKey(mnemonic string, path accounts.DerivationPath) (*ecdsa.Pri
 	return crypto.ToECDSA(rawPrivKey)
 }
 
+// fakeNetworkParams is used for HD key derivation and provides fake network parameters.
 type fakeNetworkParams struct{}
 
 func (f fakeNetworkParams) HDPrivKeyVersion() [4]byte {