From 019de6dc09a32ce36429572b1ebb21f9757a4755 Mon Sep 17 00:00:00 2001
From: Jianping Wu <jianping.wu@gmail.com>
Date: Mon, 19 Nov 2018 17:04:39 -0800
Subject: [PATCH] Used hash of the first TxIn as namespace id. This ensures
 that the namespace id is unqiue. TODO: verify that the TxIn is indeed the
 hash of the first TxIn.

---
 src/script/keva.cpp              | 21 +++++++++++++++++++--
 src/script/keva.h                |  8 +++++++-
 src/wallet/rpckeva.cpp           | 30 +++++++++++++++---------------
 src/wallet/rpcwallet.cpp         | 12 ++++++++----
 src/wallet/rpcwallet.h           |  4 +++-
 src/wallet/test/wallet_tests.cpp |  3 ++-
 src/wallet/wallet.cpp            | 27 ++++++++++++++++++++-------
 src/wallet/wallet.h              |  1 +
 8 files changed, 75 insertions(+), 31 deletions(-)

diff --git a/src/script/keva.cpp b/src/script/keva.cpp
index ad9d747d1..b6814535c 100644
--- a/src/script/keva.cpp
+++ b/src/script/keva.cpp
@@ -3,10 +3,12 @@
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
 #include <script/keva.h>
+#include <hash.h>
+#include "base58.h"
 
-#include <uint256.h>
+const std::string CKevaScript::KEVA_DISPLAY_NAME_KEY = "_KEVA_NS_";
 
-std::string CKevaScript::KEVA_DISPLAY_NAME_KEY = "_KEVA_NS_";
+const unsigned char CKevaScript::NAMESPACE_PREFIX = 21; // 2 in base58
 
 CKevaScript::CKevaScript (const CScript& script)
   : op(OP_NOP), address(script)
@@ -85,3 +87,18 @@ CScript CKevaScript::buildKevaNamespace(const CScript& addr, const valtype& name
   return prefix + addr;
 }
 
+CScript CKevaScript::replaceKevaNamespace(const CScript& oldScript, const uint256& txId, valtype& kaveNamespace)
+{
+  CKevaScript kevaOp(oldScript);
+  if (!kevaOp.isNamespaceRegistration()) {
+    assert (false);
+    return CScript();
+  }
+
+  const valtype& displayName = kevaOp.getOpNamespaceDisplayName();
+  kaveNamespace = ToByteVector(Hash160(ToByteVector(txId)));
+  kaveNamespace.insert(kaveNamespace.begin(), NAMESPACE_PREFIX);
+  //kaveNamespace = EncodeBase58(kaveNamespaceVal);
+  return CKevaScript::buildKevaNamespace(kevaOp.getAddress(), kaveNamespace, displayName);
+}
+
diff --git a/src/script/keva.h b/src/script/keva.h
index f54565940..c1c222620 100644
--- a/src/script/keva.h
+++ b/src/script/keva.h
@@ -5,6 +5,7 @@
 #ifndef H_BITCOIN_SCRIPT_KEVA
 #define H_BITCOIN_SCRIPT_KEVA
 
+#include <uint256.h>
 #include <script/script.h>
 
 class uint160;
@@ -42,7 +43,9 @@ public:
    * The key pointing to the internal display name. This is the first
    * key created when a namespace is registered.
    */
-  static std::string KEVA_DISPLAY_NAME_KEY;
+  static const std::string KEVA_DISPLAY_NAME_KEY;
+
+  static const unsigned char NAMESPACE_PREFIX;
 
   /**
    * Parse a script and determine whether it is a valid name script.  Sets
@@ -234,6 +237,9 @@ public:
   static CScript buildKevaPut(const CScript& addr, const valtype& nameSpace,
                                 const valtype& key, const valtype& value);
 
+
+  static CScript replaceKevaNamespace(const CScript& oldScript, const uint256& txId, valtype& kaveNamespace);
+
 };
 
 #endif // H_BITCOIN_SCRIPT_KEVA
diff --git a/src/wallet/rpckeva.cpp b/src/wallet/rpckeva.cpp
index 07805f853..24a118181 100644
--- a/src/wallet/rpckeva.cpp
+++ b/src/wallet/rpckeva.cpp
@@ -21,7 +21,8 @@
 
 #include <univalue.h>
 
-const unsigned char NAMESPACE_PREFIX = 21; // 2 in base58
+const int NAMESPACE_LENGTH           =  21;
+const std::string DUMMY_NAMESPACE    =  "___DUMMY_NAMESPACE___";
 
 
 /* ************************************************************************** */
@@ -71,34 +72,32 @@ UniValue keva_namespace(const JSONRPCRequest& request)
 
   CKeyID keyId = pubKey.GetID();
 
-  // The namespace name is: Hash160(Hash160(keyId) || displayName)
-  // JWU TODO: double check this! How can node verify this!!!???
-  valtype toHash = ToByteVector(Hash160(ToByteVector(keyId)));
-  toHash.insert(toHash.end(), displayName.begin(), displayName.end());
-  valtype namespaceHashVal = ToByteVector(Hash160(toHash));
-  namespaceHashVal.insert(namespaceHashVal.begin(), NAMESPACE_PREFIX);
-  const std::string namespaceHash = EncodeBase58(namespaceHashVal);
+  // The namespace name is: Hash160("first txin" || displayName)
+  // For now we don't know the first txin, so use dummy name here.
+  // It will be replaced later in CreateTransaction.
+  valtype namespaceDummy = ToByteVector(std::string(DUMMY_NAMESPACE));
+  assert(namespaceDummy.size() == NAMESPACE_LENGTH);
 
-  //const CScript addrName = GetScriptForDestination(keyId);
   CScript redeemScript = GetScriptForDestination(WitnessV0KeyHash(keyId));
   CScriptID scriptHash = CScriptID(redeemScript);
   CScript addrName = GetScriptForDestination(scriptHash);
-  const CScript newScript = CKevaScript::buildKevaNamespace(addrName, namespaceHashVal, displayName);
+  const CScript newScript = CKevaScript::buildKevaNamespace(addrName, namespaceDummy, displayName);
 
   CCoinControl coinControl;
   CWalletTx wtx;
-  SendMoneyToScript(pwallet, newScript, nullptr,
+  valtype kevaNamespace;
+  SendMoneyToScript(pwallet, newScript, nullptr, kevaNamespace,
                      KEVA_LOCKED_AMOUNT, false, wtx, coinControl);
-
   keyName.KeepKey();
 
+  std::string kevaNamespaceBase58 = EncodeBase58(kevaNamespace);
   const std::string txid = wtx.GetHash().GetHex();
   LogPrintf("keva_namespace: namespace=%s, displayName=%s, tx=%s\n",
-             namespaceHash.c_str(), displayNameStr.c_str(), txid.c_str());
+             kevaNamespaceBase58.c_str(), displayNameStr.c_str(), txid.c_str());
 
   UniValue res(UniValue::VARR);
   res.push_back(txid);
-  res.push_back(namespaceHash);
+  res.push_back(kevaNamespaceBase58);
 
   return res;
 }
@@ -275,7 +274,8 @@ UniValue keva_put(const JSONRPCRequest& request)
 
   CCoinControl coinControl;
   CWalletTx wtx;
-  SendMoneyToScript(pwallet, kevaScript, &txIn,
+  valtype empty;
+  SendMoneyToScript(pwallet, kevaScript, &txIn, empty,
                      KEVA_LOCKED_AMOUNT, false, wtx, coinControl);
 
   if (usedKey) {
diff --git a/src/wallet/rpcwallet.cpp b/src/wallet/rpcwallet.cpp
index 46d6cc821..d271efa52 100644
--- a/src/wallet/rpcwallet.cpp
+++ b/src/wallet/rpcwallet.cpp
@@ -428,7 +428,8 @@ static void SendMoney(CWallet * const pwallet, const CTxDestination &address, CA
     int nChangePosRet = -1;
     CRecipient recipient = {scriptPubKey, nValue, fSubtractFeeFromAmount};
     vecSend.push_back(recipient);
-    if (!pwallet->CreateTransaction(vecSend, nullptr, wtxNew, reservekey, nFeeRequired, nChangePosRet, strError, coin_control)) {
+    std::vector<unsigned char> empty;
+    if (!pwallet->CreateTransaction(vecSend, nullptr, empty, wtxNew, reservekey, nFeeRequired, nChangePosRet, strError, coin_control)) {
         if (!fSubtractFeeFromAmount && nValue + nFeeRequired > curBalance)
             strError = strprintf("Error: This transaction requires a transaction fee of at least %s", FormatMoney(nFeeRequired));
         throw JSONRPCError(RPC_WALLET_ERROR, strError);
@@ -441,7 +442,9 @@ static void SendMoney(CWallet * const pwallet, const CTxDestination &address, CA
 }
 
 void SendMoneyToScript(CWallet* const pwallet, const CScript &scriptPubKey,
-                       const CTxIn* withInput, CAmount nValue,
+                       const CTxIn* withInput,
+                       std::vector<unsigned char>& kevaNamespace,
+                       CAmount nValue,
                        bool fSubtractFeeFromAmount, CWalletTx& wtxNew,
                        const CCoinControl& coin_control)
 {
@@ -478,7 +481,7 @@ void SendMoneyToScript(CWallet* const pwallet, const CScript &scriptPubKey,
     int nChangePosRet = -1;
     CRecipient recipient = {scriptPubKey, nValue, fSubtractFeeFromAmount};
     vecSend.push_back(recipient);
-    if (!pwallet->CreateTransaction(vecSend, withInput, wtxNew, reservekey, nFeeRequired, nChangePosRet, strError, coin_control)) {
+    if (!pwallet->CreateTransaction(vecSend, withInput, kevaNamespace, wtxNew, reservekey, nFeeRequired, nChangePosRet, strError, coin_control)) {
         if (!fSubtractFeeFromAmount && nValue + nFeeRequired > curBalance)
             strError = strprintf("Error: This transaction requires a transaction fee of at least %s", FormatMoney(nFeeRequired));
         throw JSONRPCError(RPC_WALLET_ERROR, strError);
@@ -1200,7 +1203,8 @@ UniValue sendmany(const JSONRPCRequest& request)
     CAmount nFeeRequired = 0;
     int nChangePosRet = -1;
     std::string strFailReason;
-    bool fCreated = pwallet->CreateTransaction(vecSend, nullptr, wtx, keyChange, nFeeRequired, nChangePosRet, strFailReason, coin_control);
+    std::vector<unsigned char> empty; empty;
+    bool fCreated = pwallet->CreateTransaction(vecSend, nullptr, empty, wtx, keyChange, nFeeRequired, nChangePosRet, strFailReason, coin_control);
     if (!fCreated)
         throw JSONRPCError(RPC_WALLET_INSUFFICIENT_FUNDS, strFailReason);
     CValidationState state;
diff --git a/src/wallet/rpcwallet.h b/src/wallet/rpcwallet.h
index 499854639..f6a3c0a82 100644
--- a/src/wallet/rpcwallet.h
+++ b/src/wallet/rpcwallet.h
@@ -27,7 +27,9 @@ std::string HelpRequiringPassphrase(CWallet *);
 void EnsureWalletIsUnlocked(CWallet *);
 bool EnsureWalletIsAvailable(CWallet *, bool avoidException);
 void SendMoneyToScript(CWallet* pwallet, const CScript& scriptPubKey,
-                       const CTxIn* withInput, CAmount nValue,
+                       const CTxIn* withInput,
+                       std::vector<unsigned char>& kevaNamespace,
+                       CAmount nValue,
                        bool fSubtractFeeFromAmount, CWalletTx& wtxNew,
                        const CCoinControl& coin_control);
 
diff --git a/src/wallet/test/wallet_tests.cpp b/src/wallet/test/wallet_tests.cpp
index 1a9bd046d..25bd343ea 100644
--- a/src/wallet/test/wallet_tests.cpp
+++ b/src/wallet/test/wallet_tests.cpp
@@ -636,7 +636,8 @@ public:
         int changePos = -1;
         std::string error;
         CCoinControl dummy;
-        BOOST_CHECK(wallet->CreateTransaction({recipient}, nullptr, wtx, reservekey, fee, changePos, error, dummy));
+        std::vector<unsigned char> empty;
+        BOOST_CHECK(wallet->CreateTransaction({recipient}, nullptr, empty, wtx, reservekey, fee, changePos, error, dummy));
         CValidationState state;
         BOOST_CHECK(wallet->CommitTransaction(wtx, reservekey, nullptr, state));
         CMutableTransaction blocktx;
diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 876af006f..5b6d0f4cd 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2628,7 +2628,8 @@ bool CWallet::FundTransaction(CMutableTransaction& tx, CAmount& nFeeRet, int& nC
 
     CReserveKey reservekey(this);
     CWalletTx wtx;
-    if (!CreateTransaction(vecSend, nullptr, wtx, reservekey, nFeeRet, nChangePosInOut, strFailReason, coinControl, false)) {
+    std::vector<unsigned char> empty;
+    if (!CreateTransaction(vecSend, nullptr, empty, wtx, reservekey, nFeeRet, nChangePosInOut, strFailReason, coinControl, false)) {
         return false;
     }
 
@@ -2689,6 +2690,7 @@ OutputType CWallet::TransactionChangeType(OutputType change_type, const std::vec
 
 bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend,
                                 const CTxIn* withInput,
+                                std::vector<unsigned char>& kaveNamespace,
                                 CWalletTx& wtxNew, CReserveKey& reservekey, CAmount& nFeeRet,
                                 int& nChangePosInOut, std::string& strFailReason, const CCoinControl& coin_control, bool sign)
 {
@@ -2708,8 +2710,9 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend,
         if (recipient.fSubtractFeeFromAmount)
             nSubtractFeeFromAmount++;
 
-        if (CKevaScript::isKevaScript (recipient.scriptPubKey))
+        if (CKevaScript::isKevaScript(recipient.scriptPubKey)) {
             isKevacoin = true;
+        }
     }
     if (vecSend.empty())
     {
@@ -2919,9 +2922,21 @@ bool CWallet::CreateTransaction(const std::vector<CRecipient>& vecSend,
                 // and in the spirit of "smallest possible change from prior
                 // behavior."
                 const uint32_t nSequence = coin_control.signalRbf ? MAX_BIP125_RBF_SEQUENCE : (CTxIn::SEQUENCE_FINAL - 1);
-                for (const auto& coin : setCoins)
-                    txNew.vin.push_back(CTxIn(coin.outpoint,CScript(),
-                                              nSequence));
+                bool kevaDummyReplaced = false;
+                for (const auto& coin : setCoins) {
+                    txNew.vin.push_back(CTxIn(coin.outpoint,CScript(), nSequence));
+                    if (isKevacoin && !kevaDummyReplaced) {
+                        for (std::vector<CTxOut>::iterator iter = txNew.vout.begin(); iter != txNew.vout.end(); ++iter) {
+                            CScript dummyScript = iter->scriptPubKey;
+                            CKevaScript kevaOp(dummyScript);
+                            if (kevaOp.isKevaOp() && kevaOp.isNamespaceRegistration()) {
+                                iter->scriptPubKey = CKevaScript::replaceKevaNamespace(dummyScript, coin.outpoint.hash, kaveNamespace);
+                                kevaDummyReplaced = true;
+                                break;
+                            }
+                        }
+                    }
+                }
 
                 // Fill in dummy signatures for fee calculation.
                 if (!DummySignTx(txNew, setCoins)) {
@@ -3131,11 +3146,9 @@ bool CWallet::CommitTransaction(CWalletTx& wtxNew, CReserveKey& reservekey, CCon
         {
             // Broadcast
             if (!wtx.AcceptToMemoryPool(maxTxFee, state)) {
-                printf("JWU Transaction cannot be broadcast immediately! \n");
                 LogPrintf("CommitTransaction(): Transaction cannot be broadcast immediately, %s\n", state.GetRejectReason());
                 // TODO: if we expect the failure to be long term or permanent, instead delete wtx from the wallet and return failure.
             } else {
-                printf("JWU Transaction CAN OK be broadcast immediately! \n");
                 wtx.RelayWalletTransaction(connman);
             }
         }
diff --git a/src/wallet/wallet.h b/src/wallet/wallet.h
index 86c04cf9b..814f38a39 100644
--- a/src/wallet/wallet.h
+++ b/src/wallet/wallet.h
@@ -993,6 +993,7 @@ public:
      */
     bool CreateTransaction(const std::vector<CRecipient>& vecSend,
                            const CTxIn* withInput,
+                           std::vector<unsigned char>& kaveNamespace,
                            CWalletTx& wtxNew, CReserveKey& reservekey, CAmount& nFeeRet, int& nChangePosInOut,
                            std::string& strFailReason, const CCoinControl& coin_control, bool sign = true);
     bool CommitTransaction(CWalletTx& wtxNew, CReserveKey& reservekey, CConnman* connman, CValidationState& state);