AddressScriptHash.go

package btcaddress

import (
	"golang.org/x/crypto/ripemd160"
	"errors"
)

// NewAddressScriptHash returns a new AddressScriptHash.
func NewAddressScriptHash(serializedScript []byte, net *Params) (*AddressScriptHash, error) {
	scriptHash := Hash160(serializedScript)
	return newAddressScriptHashFromHash(scriptHash, net)
}

// NewAddressScriptHashFromHash returns a new AddressScriptHash.  scriptHash
// must be 20 bytes.
func NewAddressScriptHashFromHash160(scriptHash []byte, net *Params) (*AddressScriptHash, error) {
	return newAddressScriptHashFromHash(scriptHash, net)
}

// AddressScriptHash is an Address for a pay-to-script-hash (P2SH)
// transaction.
type AddressScriptHash struct {
	hash  [ripemd160.Size]byte
	magic Magic
}

// newAddressScriptHashFromHash is the internal API to create a script hash
// address with a known leading identifier byte for a network, rather than
// looking it up through its parameters.  This is useful when creating a new
// address structure from a string encoding where the identifer byte is already
// known.
func newAddressScriptHashFromHash(scriptHash []byte, net *Params) (*AddressScriptHash, error) {
	// Check for a valid script hash length.
	if len(scriptHash) != ripemd160.Size {
		return nil, errors.New("scriptHash must be 20 bytes")
	}

	addr := &AddressScriptHash{magic: net.ScriptHashMagic}
	copy(addr.hash[:], scriptHash)
	return addr, nil
}

// EncodeAddress returns the string encoding of a pay-to-script-hash
// address.  Part of the Address interface.
func (a *AddressScriptHash) EncodeAddress() string {
	return EncodeAddressFromH160(a.hash[:], a.magic)
}

// ScriptAddress returns the bytes to be included in a txout script to pay
// to a script hash.  Part of the Address interface.
func (a *AddressScriptHash) ScriptAddress() []byte {
	return a.hash[:]
}

// IsForNet returns whether or not the pay-to-script-hash address is associated
// with the passed bitcoin network.
func (a *AddressScriptHash) IsForNet(net *Params) bool {
	return a.magic == net.ScriptHashMagic
}

// String returns a human-readable string for the pay-to-script-hash address.
// This is equivalent to calling EncodeAddress, but is provided so the type can
// be used as a fmt.Stringer.
func (a *AddressScriptHash) String() string {
	return a.EncodeAddress()
}

// Hash160 returns the underlying array of the script hash.  This can be useful
// when an array is more appropiate than a slice (for example, when used as map
// keys).
func (a *AddressScriptHash) Hash160() *[ripemd160.Size]byte {
	return &a.hash
}