From 2134a817f34f008222c12c883d3621e46c1155f4 Mon Sep 17 00:00:00 2001
From: Alex Grintsvayg <git@grin.io>
Date: Wed, 27 Jun 2018 15:41:21 -0400
Subject: [PATCH] change bech32 prefix, add genesis hash, write our own
 DecodeAddress

---
 lbrycrd/address.go | 58 ++++++++++++++++++++++++++++++++++++++++++++++
 lbrycrd/client.go  | 13 +++++++++--
 2 files changed, 69 insertions(+), 2 deletions(-)
 create mode 100644 lbrycrd/address.go

diff --git a/lbrycrd/address.go b/lbrycrd/address.go
new file mode 100644
index 0000000..90f6197
--- /dev/null
+++ b/lbrycrd/address.go
@@ -0,0 +1,58 @@
+package lbrycrd
+
+import (
+	"encoding/hex"
+
+	"github.com/lbryio/lbry.go/errors"
+
+	"github.com/btcsuite/btcd/chaincfg"
+	"github.com/btcsuite/btcutil"
+	"github.com/btcsuite/btcutil/base58"
+	"golang.org/x/crypto/ripemd160"
+)
+
+// DecodeAddress decodes the string encoding of an address and returns
+// the Address if addr is a valid encoding for a known address type.
+//
+// The bitcoin network the address is associated with is extracted if possible.
+// When the address does not encode the network, such as in the case of a raw
+// public key, the address will be associated with the passed defaultNet.
+func DecodeAddress(addr string, defaultNet *chaincfg.Params) (btcutil.Address, error) {
+	// Serialized public keys are either 65 bytes (130 hex chars) if
+	// uncompressed/hybrid or 33 bytes (66 hex chars) if compressed.
+	if len(addr) == 130 || len(addr) == 66 {
+		serializedPubKey, err := hex.DecodeString(addr)
+		if err != nil {
+			return nil, err
+		}
+		return btcutil.NewAddressPubKey(serializedPubKey, defaultNet)
+	}
+
+	// Switch on decoded length to determine the type.
+	decoded, netID, err := base58.CheckDecode(addr)
+	if err != nil {
+		if err == base58.ErrChecksum {
+			return nil, btcutil.ErrChecksumMismatch
+		}
+		return nil, errors.Err("decoded address is of unknown format")
+	}
+
+	switch len(decoded) {
+	case ripemd160.Size: // P2PKH or P2SH
+		isP2PKH := chaincfg.IsPubKeyHashAddrID(netID)
+		isP2SH := chaincfg.IsScriptHashAddrID(netID)
+		switch hash160 := decoded; {
+		case isP2PKH && isP2SH:
+			return nil, btcutil.ErrAddressCollision
+		case isP2PKH:
+			return btcutil.NewAddressPubKeyHash(hash160, &chaincfg.Params{PubKeyHashAddrID: netID})
+		case isP2SH:
+			return btcutil.NewAddressScriptHashFromHash(hash160, &chaincfg.Params{ScriptHashAddrID: netID})
+		default:
+			return nil, btcutil.ErrUnknownAddressType
+		}
+
+	default:
+		return nil, errors.Err("decoded address is of unknown size")
+	}
+}
diff --git a/lbrycrd/client.go b/lbrycrd/client.go
index e55ba22..e66d135 100644
--- a/lbrycrd/client.go
+++ b/lbrycrd/client.go
@@ -16,11 +16,20 @@ import (
 
 const DefaultPort = 9245
 
+var GenesisHash = chainhash.Hash([chainhash.HashSize]byte{ // Make go vet happy.
+	0x9c, 0x89, 0x28, 0x3b, 0xa0, 0xf3, 0x22, 0x7f,
+	0x6c, 0x03, 0xb7, 0x02, 0x16, 0xb9, 0xf6, 0x65,
+	0xf0, 0x11, 0x8d, 0x5e, 0x0f, 0xa7, 0x29, 0xce,
+	0xdf, 0x4f, 0xb3, 0x4d, 0x6a, 0x34, 0xf4, 0x63,
+})
+
 // MainNetParams define the lbrycrd network. See https://github.com/lbryio/lbrycrd/blob/master/src/chainparams.cpp
 var MainNetParams = chaincfg.Params{
 	PubKeyHashAddrID: 0x55,
 	ScriptHashAddrID: 0x7a,
 	PrivateKeyID:     0x1c,
+	Bech32HRPSegwit:  "not-used", // we don't have this (yet)
+	GenesisHash:      &GenesisHash,
 }
 
 func init() {
@@ -85,7 +94,7 @@ var errInsufficientFunds = errors.Base("insufficient funds")
 
 // SimpleSend is a convenience function to send credits to an address (0 min confirmations)
 func (c *Client) SimpleSend(toAddress string, amount float64) (*chainhash.Hash, error) {
-	decodedAddress, err := btcutil.DecodeAddress(toAddress, &MainNetParams)
+	decodedAddress, err := DecodeAddress(toAddress, &MainNetParams)
 	if err != nil {
 		return nil, errors.Err(err)
 	}
@@ -106,7 +115,7 @@ func (c *Client) SimpleSend(toAddress string, amount float64) (*chainhash.Hash,
 }
 
 //func (c *Client) SendWithSplit(toAddress string, amount float64, numUTXOs int) (*chainhash.Hash, error) {
-//	decodedAddress, err := btcutil.DecodeAddress(toAddress, &MainNetParams)
+//	decodedAddress, err := DecodeAddress(toAddress, &MainNetParams)
 //	if err != nil {
 //		return nil, errors.Wrap(err, 0)
 //	}