text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2012 The Bitcoin developers
  // Distributed under the MIT/X11 software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include "alert.h"
  #include "checkpoints.h"
  #include "db.h"
  #include "net.h"
  #include "init.h" 
  #include "ui_interface.h"
  #include "kernel.h"
  #include <boost/algorithm/string/replace.hpp>
  #include <boost/filesystem.hpp>
  #include <boost/filesystem/fstream.hpp>
  #include <boost/random/mersenne_twister.hpp>
  #include <boost/random/uniform_int_distribution.hpp>
  
  using namespace std;
  using namespace boost;
  
  //
  // Global state
  //
  
  CCriticalSection cs_setpwalletRegistered;
  set<CWallet*> setpwalletRegistered; 
  
  CCriticalSection cs_main;
  
  CTxMemPool mempool;
  unsigned int nTransactionsUpdated = 0;
  
  map<uint256, CBlockIndex*> mapBlockIndex;
  set<pair<COutPoint, unsigned int> > setStakeSeen;
  uint256 hashGenesisBlock = hashGenesisBlockOfficial;
  static CBigNum bnProofOfWorkLimit(~uint256(0) >> 20);
  static CBigNum bnProofOfStakeLimit(~uint256(0) >> 20);
  
  static CBigNum bnProofOfWorkLimitTestNet(~uint256(0) >> 16);
  static CBigNum bnProofOfStakeLimitTestNet(~uint256(0) >> 30);
  
  unsigned int nStakeMinAge = 60 * 60 *  8  * 1;	
  unsigned int nStakeMaxAge = 60 * 60 * 24 * 30;
  unsigned int nStakeTargetSpacing = 60;			
  
  int64 nChainStartTime = 1459234800;
  int nCoinbaseMaturity = 10;
  CBlockIndex* pindexGenesisBlock = NULL;
  int nBestHeight = -1;
  CBigNum bnBestChainTrust = 0;
  CBigNum bnBestInvalidTrust = 0;
  uint256 hashBestChain = 0;
  CBlockIndex* pindexBest = NULL;
  int64 nTimeBestReceived = 0;
  
  CMedianFilter<int> cPeerBlockCounts(5, 0); // Amount of blocks that other nodes claim to have
  
  map<uint256, CBlock*> mapOrphanBlocks;
  multimap<uint256, CBlock*> mapOrphanBlocksByPrev;
  set<pair<COutPoint, unsigned int> > setStakeSeenOrphan;
  map<uint256, uint256> mapProofOfStake;
  
  map<uint256, CDataStream*> mapOrphanTransactions;
  map<uint256, map<uint256, CDataStream*> > mapOrphanTransactionsByPrev;
  
  // Constant stuff for coinbase transactions we create:
  CScript COINBASE_FLAGS;
  
  const string strMessageMagic = "OfferlibationCoin Signed Message:\n";
  
  double dHashesPerSec;
  int64 nHPSTimerStart;
  
  // Settings
  int64 nTransactionFee = MIN_TX_FEE;
  
  
  static const int NUM_OF_POW_CHECKPOINT = 1;
  static const int checkpointPoWHeight[NUM_OF_POW_CHECKPOINT][2] =
  {
          {5,  5},
  };
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // dispatching functions
  //
  
  // These functions dispatch to one or all registered wallets
  
  
  void RegisterWallet(CWallet* pwalletIn)
  {
      {
          LOCK(cs_setpwalletRegistered);
          setpwalletRegistered.insert(pwalletIn);
      }
  }
  
  void UnregisterWallet(CWallet* pwalletIn)
  {
      {
          LOCK(cs_setpwalletRegistered);
          setpwalletRegistered.erase(pwalletIn);
      }
  }
  
  // check whether the passed transaction is from us
  bool static IsFromMe(CTransaction& tx)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          if (pwallet->IsFromMe(tx))
              return true;
      return false;
  }
  
  // get the wallet transaction with the given hash (if it exists)
  bool static GetTransaction(const uint256& hashTx, CWalletTx& wtx)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          if (pwallet->GetTransaction(hashTx,wtx))
              return true;
      return false;
  }
  
  // erases transaction with the given hash from all wallets
  void static EraseFromWallets(uint256 hash)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->EraseFromWallet(hash);
  }
  
  // make sure all wallets know about the given transaction, in the given block
  void SyncWithWallets(const CTransaction& tx, const CBlock* pblock, bool fUpdate, bool fConnect)
  {
      if (!fConnect)
      {
          // ppcoin: wallets need to refund inputs when disconnecting coinstake
          if (tx.IsCoinStake())
          {
              BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
                  if (pwallet->IsFromMe(tx))
                      pwallet->DisableTransaction(tx);
          }
          return;
      }
  
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->AddToWalletIfInvolvingMe(tx, pblock, fUpdate);
  }
  
  // notify wallets about a new best chain
  void static SetBestChain(const CBlockLocator& loc)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->SetBestChain(loc);
  }
  
  // notify wallets about an updated transaction
  void static UpdatedTransaction(const uint256& hashTx)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->UpdatedTransaction(hashTx);
  }
  
  // dump all wallets
  void static PrintWallets(const CBlock& block)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->PrintWallet(block);
  }
  
  // notify wallets about an incoming inventory (for request counts)
  void static Inventory(const uint256& hash)
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->Inventory(hash);
  }
  
  // ask wallets to resend their transactions
  void ResendWalletTransactions()
  {
      BOOST_FOREACH(CWallet* pwallet, setpwalletRegistered)
          pwallet->ResendWalletTransactions();
  }
  
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // mapOrphanTransactions
  //
  
  bool AddOrphanTx(const CDataStream& vMsg)
  {
      CTransaction tx;
      CDataStream(vMsg) >> tx;
      uint256 hash = tx.GetHash();
      if (mapOrphanTransactions.count(hash))
          return false;
  
      CDataStream* pvMsg = new CDataStream(vMsg);
  
      // Ignore big transactions, to avoid a
      // send-big-orphans memory exhaustion attack. If a peer has a legitimate
      // large transaction with a missing parent then we assume
      // it will rebroadcast it later, after the parent transaction(s)
      // have been mined or received.
      // 10,000 orphans, each of which is at most 5,000 bytes big is
      // at most 500 megabytes of orphans:
      if (pvMsg->size() > 5000)
      {
          printf("ignoring large orphan tx (size: %"PRIszu", hash: %s)\n", pvMsg->size(), hash.ToString().substr(0,10).c_str());
          delete pvMsg;
          return false;
      }
  
      mapOrphanTransactions[hash] = pvMsg;
      BOOST_FOREACH(const CTxIn& txin, tx.vin)
          mapOrphanTransactionsByPrev[txin.prevout.hash].insert(make_pair(hash, pvMsg));
  
      printf("stored orphan tx %s (mapsz %"PRIszu")\n", hash.ToString().substr(0,10).c_str(),
          mapOrphanTransactions.size());
      return true;
  }
  
  void static EraseOrphanTx(uint256 hash)
  {
      if (!mapOrphanTransactions.count(hash))
          return;
      const CDataStream* pvMsg = mapOrphanTransactions[hash];
      CTransaction tx;
      CDataStream(*pvMsg) >> tx;
      BOOST_FOREACH(const CTxIn& txin, tx.vin)
      {
          mapOrphanTransactionsByPrev[txin.prevout.hash].erase(hash);
          if (mapOrphanTransactionsByPrev[txin.prevout.hash].empty())
              mapOrphanTransactionsByPrev.erase(txin.prevout.hash);
      }
      delete pvMsg;
      mapOrphanTransactions.erase(hash);
  }
  
  unsigned int LimitOrphanTxSize(unsigned int nMaxOrphans)
  {
      unsigned int nEvicted = 0;
      while (mapOrphanTransactions.size() > nMaxOrphans)
      {
          // Evict a random orphan:
          uint256 randomhash = GetRandHash();
          map<uint256, CDataStream*>::iterator it = mapOrphanTransactions.lower_bound(randomhash);
          if (it == mapOrphanTransactions.end())
              it = mapOrphanTransactions.begin();
          EraseOrphanTx(it->first);
          ++nEvicted;
      }
      return nEvicted;
  }
  
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // CTransaction and CTxIndex
  //
  
  bool CTransaction::ReadFromDisk(CTxDB& txdb, COutPoint prevout, CTxIndex& txindexRet)
  {
      SetNull();
      if (!txdb.ReadTxIndex(prevout.hash, txindexRet))
          return false;
      if (!ReadFromDisk(txindexRet.pos))
          return false;
      if (prevout.n >= vout.size())
      {
          SetNull();
          return false;
      }
      return true;
  }
  
  bool CTransaction::ReadFromDisk(CTxDB& txdb, COutPoint prevout)
  {
      CTxIndex txindex;
      return ReadFromDisk(txdb, prevout, txindex);
  }
  
  bool CTransaction::ReadFromDisk(COutPoint prevout)
  {
      CTxDB txdb("r");
      CTxIndex txindex;
      return ReadFromDisk(txdb, prevout, txindex);
  }
  
  bool CTransaction::IsStandard() const
  {
      if (nVersion > CTransaction::CURRENT_VERSION)
          return false;
  
      BOOST_FOREACH(const CTxIn& txin, vin)
      {
          // Biggest 'standard' txin is a 3-signature 3-of-3 CHECKMULTISIG
          // pay-to-script-hash, which is 3 ~80-byte signatures, 3
          // ~65-byte public keys, plus a few script ops.
          if (txin.scriptSig.size() > 500)
              return false;
          if (!txin.scriptSig.IsPushOnly())
              return false;
      }
      BOOST_FOREACH(const CTxOut& txout, vout) {
          if (!::IsStandard(txout.scriptPubKey))
              return false;
          if (txout.nValue == 0)
              return false;
      }
      return true;
  }
  
  //
  // Check transaction inputs, and make sure any
  // pay-to-script-hash transactions are evaluating IsStandard scripts
  //
  // Why bother? To avoid denial-of-service attacks; an attacker
  // can submit a standard HASH... OP_EQUAL transaction,
  // which will get accepted into blocks. The redemption
  // script can be anything; an attacker could use a very
  // expensive-to-check-upon-redemption script like:
  //   DUP CHECKSIG DROP ... repeated 100 times... OP_1
  //
  bool CTransaction::AreInputsStandard(const MapPrevTx& mapInputs) const
  {
      if (IsCoinBase())
          return true; // Coinbases don't use vin normally
  
      for (unsigned int i = 0; i < vin.size(); i++)
      {
          const CTxOut& prev = GetOutputFor(vin[i], mapInputs);
  
          vector<vector<unsigned char> > vSolutions;
          txnouttype whichType;
          // get the scriptPubKey corresponding to this input:
          const CScript& prevScript = prev.scriptPubKey;
          if (!Solver(prevScript, whichType, vSolutions))
              return false;
          int nArgsExpected = ScriptSigArgsExpected(whichType, vSolutions);
          if (nArgsExpected < 0)
              return false;
  
          // Transactions with extra stuff in their scriptSigs are
          // non-standard. Note that this EvalScript() call will
          // be quick, because if there are any operations
          // beside "push data" in the scriptSig the
          // IsStandard() call returns false
          vector<vector<unsigned char> > stack;
          if (!EvalScript(stack, vin[i].scriptSig, *this, i, 0))
              return false;
  
          if (whichType == TX_SCRIPTHASH)
          {
              if (stack.empty())
                  return false;
              CScript subscript(stack.back().begin(), stack.back().end());
              vector<vector<unsigned char> > vSolutions2;
              txnouttype whichType2;
              if (!Solver(subscript, whichType2, vSolutions2))
                  return false;
              if (whichType2 == TX_SCRIPTHASH)
                  return false;
  
              int tmpExpected;
              tmpExpected = ScriptSigArgsExpected(whichType2, vSolutions2);
              if (tmpExpected < 0)
                  return false;
              nArgsExpected += tmpExpected;
          }
  
          if (stack.size() != (unsigned int)nArgsExpected)
              return false;
      }
  
      return true;
  }
  
  unsigned int
  CTransaction::GetLegacySigOpCount() const
  {
      unsigned int nSigOps = 0;
      BOOST_FOREACH(const CTxIn& txin, vin)
      {
          nSigOps += txin.scriptSig.GetSigOpCount(false);
      }
      BOOST_FOREACH(const CTxOut& txout, vout)
      {
          nSigOps += txout.scriptPubKey.GetSigOpCount(false);
      }
      return nSigOps;
  }
  
  
  int CMerkleTx::SetMerkleBranch(const CBlock* pblock)
  {
      if (fClient)
      {
          if (hashBlock == 0)
              return 0;
      }
      else
      {
          CBlock blockTmp;
          if (pblock == NULL)
          {
              // Load the block this tx is in
              CTxIndex txindex;
              if (!CTxDB("r").ReadTxIndex(GetHash(), txindex))
                  return 0;
              if (!blockTmp.ReadFromDisk(txindex.pos.nFile, txindex.pos.nBlockPos))
                  return 0;
              pblock = &blockTmp;
          }
  
          // Update the tx's hashBlock
          hashBlock = pblock->GetHash();
  
          // Locate the transaction
          for (nIndex = 0; nIndex < (int)pblock->vtx.size(); nIndex++)
              if (pblock->vtx[nIndex] == *(CTransaction*)this)
                  break;
          if (nIndex == (int)pblock->vtx.size())
          {
              vMerkleBranch.clear();
              nIndex = -1;
              printf("ERROR: SetMerkleBranch() : couldn't find tx in block\n");
              return 0;
          }
  
          // Fill in merkle branch
          vMerkleBranch = pblock->GetMerkleBranch(nIndex);
      }
  
      // Is the tx in a block that's in the main chain
      map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hashBlock);
      if (mi == mapBlockIndex.end())
          return 0;
      CBlockIndex* pindex = (*mi).second;
      if (!pindex || !pindex->IsInMainChain())
          return 0;
  
      return pindexBest->nHeight - pindex->nHeight + 1;
  }
  
  
  
  
  bool CTransaction::CheckTransaction() const
  {
      // Basic checks that don't depend on any context
      if (vin.empty())
          return DoS(10, error("CTransaction::CheckTransaction() : vin empty"));
      if (vout.empty())
          return DoS(10, error("CTransaction::CheckTransaction() : vout empty"));
      // Size limits
      if (::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
          return DoS(100, error("CTransaction::CheckTransaction() : size limits failed"));
  
      // Check for negative or overflow output values
      int64 nValueOut = 0;
      for (unsigned int i = 0; i < vout.size(); i++)
      {
          const CTxOut& txout = vout[i];
          if (txout.IsEmpty() && !IsCoinBase() && !IsCoinStake())
              return DoS(100, error("CTransaction::CheckTransaction() : txout empty for user transaction"));
  
          // ppcoin: enforce minimum output amount
          if ((!txout.IsEmpty()) && txout.nValue < MIN_TXOUT_AMOUNT)
              return DoS(100, error("CTransaction::CheckTransaction() : txout.nValue below minimum"));
  
          if (txout.nValue > MAX_MONEY)
              return DoS(100, error("CTransaction::CheckTransaction() : txout.nValue too high"));
          nValueOut += txout.nValue;
          if (!MoneyRange(nValueOut))
              return DoS(100, error("CTransaction::CheckTransaction() : txout total out of range"));
      }
  
      // Check for duplicate inputs
      set<COutPoint> vInOutPoints;
      BOOST_FOREACH(const CTxIn& txin, vin)
      {
          if (vInOutPoints.count(txin.prevout))
              return false;
          vInOutPoints.insert(txin.prevout);
      }
  
      if (IsCoinBase())
      {
          if (vin[0].scriptSig.size() < 2 || vin[0].scriptSig.size() > 100)
              return DoS(100, error("CTransaction::CheckTransaction() : coinbase script size"));
      }
      else
      {
          BOOST_FOREACH(const CTxIn& txin, vin)
              if (txin.prevout.IsNull())
                  return DoS(10, error("CTransaction::CheckTransaction() : prevout is null"));
      }
  
      return true;
  }
  
  
  int64 CTransaction::GetMinFee(unsigned int nBlockSize, bool fAllowFree,
                                enum GetMinFee_mode mode, unsigned int nBytes) const
  {
      // Base fee is either MIN_TX_FEE or MIN_RELAY_TX_FEE
      int64 nBaseFee = (mode == GMF_RELAY) ? MIN_RELAY_TX_FEE : MIN_TX_FEE;
  
      unsigned int nNewBlockSize = nBlockSize + nBytes;
      int64 nMinFee = (1 + (int64)nBytes / 1000) * nBaseFee;
  
      // To limit dust spam, require MIN_TX_FEE/MIN_RELAY_TX_FEE if any output is less than 0.01
      if (nMinFee < nBaseFee)
      {
          BOOST_FOREACH(const CTxOut& txout, vout)
              if (txout.nValue < CENT)
                  nMinFee = nBaseFee;
      }
  
      // Raise the price as the block approaches full
      if (nBlockSize != 1 && nNewBlockSize >= MAX_BLOCK_SIZE_GEN/2)
      {
          if (nNewBlockSize >= MAX_BLOCK_SIZE_GEN)
              return MAX_MONEY;
          nMinFee *= MAX_BLOCK_SIZE_GEN / (MAX_BLOCK_SIZE_GEN - nNewBlockSize);
      }
  
      if (!MoneyRange(nMinFee))
          nMinFee = MAX_MONEY;
      return nMinFee;
  }
  
  
  bool CTxMemPool::accept(CTxDB& txdb, CTransaction &tx, bool fCheckInputs,
                          bool* pfMissingInputs)
  {
      if (pfMissingInputs)
          *pfMissingInputs = false;
  
      if (!tx.CheckTransaction())
          return error("CTxMemPool::accept() : CheckTransaction failed");
  
      // Coinbase is only valid in a block, not as a loose transaction
      if (tx.IsCoinBase())
          return tx.DoS(100, error("CTxMemPool::accept() : coinbase as individual tx"));
  
      // ppcoin: coinstake is also only valid in a block, not as a loose transaction
      if (tx.IsCoinStake())
          return tx.DoS(100, error("CTxMemPool::accept() : coinstake as individual tx"));
  
      // To help v0.1.5 clients who would see it as a negative number
      if ((int64)tx.nLockTime > std::numeric_limits<int>::max())
          return error("CTxMemPool::accept() : not accepting nLockTime beyond 2038 yet");
  
      // Rather not work on nonstandard transactions (unless -testnet)
      if (!fTestNet && !tx.IsStandard())
          return error("CTxMemPool::accept() : nonstandard transaction type");
  
      // Do we already have it?
      uint256 hash = tx.GetHash();
      {
          LOCK(cs);
          if (mapTx.count(hash))
              return false;
      }
      if (fCheckInputs)
          if (txdb.ContainsTx(hash))
              return false;
  
      // Check for conflicts with in-memory transactions
      CTransaction* ptxOld = NULL;
      for (unsigned int i = 0; i < tx.vin.size(); i++)
      {
          COutPoint outpoint = tx.vin[i].prevout;
          if (mapNextTx.count(outpoint))
          {
              // Disable replacement feature for now
              return false;
  
              // Allow replacing with a newer version of the same transaction
              if (i != 0)
                  return false;
              ptxOld = mapNextTx[outpoint].ptx;
              if (ptxOld->IsFinal())
                  return false;
              if (!tx.IsNewerThan(*ptxOld))
                  return false;
              for (unsigned int i = 0; i < tx.vin.size(); i++)
              {
                  COutPoint outpoint = tx.vin[i].prevout;
                  if (!mapNextTx.count(outpoint) || mapNextTx[outpoint].ptx != ptxOld)
                      return false;
              }
              break;
          }
      }
  
      if (fCheckInputs)
      {
          MapPrevTx mapInputs;
          map<uint256, CTxIndex> mapUnused;
          bool fInvalid = false;
          if (!tx.FetchInputs(txdb, mapUnused, false, false, mapInputs, fInvalid))
          {
              if (fInvalid)
                  return error("CTxMemPool::accept() : FetchInputs found invalid tx %s", hash.ToString().substr(0,10).c_str());
              if (pfMissingInputs)
                  *pfMissingInputs = true;
              return false;
          }
  
          // Check for non-standard pay-to-script-hash in inputs
          if (!tx.AreInputsStandard(mapInputs) && !fTestNet)
              return error("CTxMemPool::accept() : nonstandard transaction input");
  
          // Note: if you modify this code to accept non-standard transactions, then
          // you should add code here to check that the transaction does a
          // reasonable number of ECDSA signature verifications.
  
          int64 nFees = tx.GetValueIn(mapInputs)-tx.GetValueOut();
          unsigned int nSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
  
          // Don't accept it if it can't get into a block
          int64 txMinFee = tx.GetMinFee(1000, false, GMF_RELAY, nSize);
          if (nFees < txMinFee)
              return error("CTxMemPool::accept() : not enough fees %s, %"PRI64d" < %"PRI64d,
                           hash.ToString().c_str(),
                           nFees, txMinFee);
  
          // Continuously rate-limit free transactions
          // This mitigates 'penny-flooding' -- sending thousands of free transactions just to
          // be annoying or make others' transactions take longer to confirm.
          if (nFees < MIN_RELAY_TX_FEE)
          {
              static CCriticalSection cs;
              static double dFreeCount;
              static int64 nLastTime;
              int64 nNow = GetTime();
  
              {
                  LOCK(cs);
                  // Use an exponentially decaying ~10-minute window:
                  dFreeCount *= pow(1.0 - 1.0/600.0, (double)(nNow - nLastTime));
                  nLastTime = nNow;
                  // -limitfreerelay unit is thousand-bytes-per-minute
                  // At default rate it would take over a month to fill 1GB
                  if (dFreeCount > GetArg("-limitfreerelay", 15)*10*1000 && !IsFromMe(tx))
                      return error("CTxMemPool::accept() : free transaction rejected by rate limiter");
                  if (fDebug)
                      printf("Rate limit dFreeCount: %g => %g\n", dFreeCount, dFreeCount+nSize);
                  dFreeCount += nSize;
              }
          }
  
          // Check against previous transactions
          // This is done last to help prevent CPU exhaustion denial-of-service attacks.
          if (!tx.ConnectInputs(txdb, mapInputs, mapUnused, CDiskTxPos(1,1,1), pindexBest, false, false))
          {
              return error("CTxMemPool::accept() : ConnectInputs failed %s", hash.ToString().substr(0,10).c_str());
          }
      }
  
      // Store transaction in memory
      {
          LOCK(cs);
          if (ptxOld)
          {
              printf("CTxMemPool::accept() : replacing tx %s with new version\n", ptxOld->GetHash().ToString().c_str());
              remove(*ptxOld);
          }
          addUnchecked(hash, tx);
      }
  
      ///// are we sure this is ok when loading transactions or restoring block txes
      // If updated, erase old tx from wallet
      if (ptxOld)
          EraseFromWallets(ptxOld->GetHash());
  
      printf("CTxMemPool::accept() : accepted %s (poolsz %"PRIszu")\n",
             hash.ToString().substr(0,10).c_str(),
             mapTx.size());
      return true;
  }
  
  bool CTransaction::AcceptToMemoryPool(CTxDB& txdb, bool fCheckInputs, bool* pfMissingInputs)
  {
      return mempool.accept(txdb, *this, fCheckInputs, pfMissingInputs);
  }
  
  bool CTxMemPool::addUnchecked(const uint256& hash, CTransaction &tx)
  {
      // Add to memory pool without checking anything.  Don't call this directly,
      // call CTxMemPool::accept to properly check the transaction first.
      {
          mapTx[hash] = tx;
          for (unsigned int i = 0; i < tx.vin.size(); i++)
              mapNextTx[tx.vin[i].prevout] = CInPoint(&mapTx[hash], i);
          nTransactionsUpdated++;
      }
      return true;
  }
  
  
  bool CTxMemPool::remove(CTransaction &tx)
  {
      // Remove transaction from memory pool
      {
          LOCK(cs);
          uint256 hash = tx.GetHash();
          if (mapTx.count(hash))
          {
              BOOST_FOREACH(const CTxIn& txin, tx.vin)
                  mapNextTx.erase(txin.prevout);
              mapTx.erase(hash);
              nTransactionsUpdated++;
          }
      }
      return true;
  }
  
  void CTxMemPool::clear()
  {
      LOCK(cs);
      mapTx.clear();
      mapNextTx.clear();
      ++nTransactionsUpdated;
  }
  
  void CTxMemPool::queryHashes(std::vector<uint256>& vtxid)
  {
      vtxid.clear();
  
      LOCK(cs);
      vtxid.reserve(mapTx.size());
      for (map<uint256, CTransaction>::iterator mi = mapTx.begin(); mi != mapTx.end(); ++mi)
          vtxid.push_back((*mi).first);
  }
  
  
  
  
  int CMerkleTx::GetDepthInMainChain(CBlockIndex* &pindexRet) const
  {
      if (hashBlock == 0 || nIndex == -1)
          return 0;
  
      // Find the block it claims to be in
      map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hashBlock);
      if (mi == mapBlockIndex.end())
          return 0;
      CBlockIndex* pindex = (*mi).second;
      if (!pindex || !pindex->IsInMainChain())
          return 0;
  
      // Make sure the merkle branch connects to this block
      if (!fMerkleVerified)
      {
          if (CBlock::CheckMerkleBranch(GetHash(), vMerkleBranch, nIndex) != pindex->hashMerkleRoot)
              return 0;
          fMerkleVerified = true;
      }
  
      pindexRet = pindex;
      return pindexBest->nHeight - pindex->nHeight + 1;
  }
  
  
  int CMerkleTx::GetBlocksToMaturity() const
  {
      if (!(IsCoinBase() || IsCoinStake()))
          return 0;
      return max(0, (nCoinbaseMaturity+20) - GetDepthInMainChain());
  }
  
  
  bool CMerkleTx::AcceptToMemoryPool(CTxDB& txdb, bool fCheckInputs)
  {
      if (fClient)
      {
          if (!IsInMainChain() && !ClientConnectInputs())
              return false;
          return CTransaction::AcceptToMemoryPool(txdb, false);
      }
      else
      {
          return CTransaction::AcceptToMemoryPool(txdb, fCheckInputs);
      }
  }
  
  bool CMerkleTx::AcceptToMemoryPool()
  {
      CTxDB txdb("r");
      return AcceptToMemoryPool(txdb);
  }
  
  
  
  bool CWalletTx::AcceptWalletTransaction(CTxDB& txdb, bool fCheckInputs)
  {
  
      {
          LOCK(mempool.cs);
          // Add previous supporting transactions first
          BOOST_FOREACH(CMerkleTx& tx, vtxPrev)
          {
              if (!(tx.IsCoinBase() || tx.IsCoinStake()))
              {
                  uint256 hash = tx.GetHash();
                  if (!mempool.exists(hash) && !txdb.ContainsTx(hash))
                      tx.AcceptToMemoryPool(txdb, fCheckInputs);
              }
          }
          return AcceptToMemoryPool(txdb, fCheckInputs);
      }
      return false;
  }
  
  
  bool CWalletTx::AcceptWalletTransaction()
  {
      CTxDB txdb("r");
      return AcceptWalletTransaction(txdb);
  }
  
  
  int CTxIndex::GetDepthInMainChain() const
  {
      // Read block header
      CBlock block;
      if (!block.ReadFromDisk(pos.nFile, pos.nBlockPos, false))
          return 0;
      // Find the block in the index
      map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(block.GetHash());
      if (mi == mapBlockIndex.end())
          return 0;
      CBlockIndex* pindex = (*mi).second;
      if (!pindex || !pindex->IsInMainChain())
          return 0;
      return 1 + nBestHeight - pindex->nHeight;
  }
  
  // Return transaction in tx, and if it was found inside a block, its hash is placed in hashBlock
  bool GetTransaction(const uint256 &hash, CTransaction &tx, uint256 &hashBlock)
  {
      {
          LOCK(cs_main);
          {
              LOCK(mempool.cs);
              if (mempool.exists(hash))
              {
                  tx = mempool.lookup(hash);
                  return true;
              }
          }
          CTxDB txdb("r");
          CTxIndex txindex;
          if (tx.ReadFromDisk(txdb, COutPoint(hash, 0), txindex))
          {
              CBlock block;
              if (block.ReadFromDisk(txindex.pos.nFile, txindex.pos.nBlockPos, false))
                  hashBlock = block.GetHash();
              return true;
          }
      }
      return false;
  }
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // CBlock and CBlockIndex
  //
  
  static CBlockIndex* pblockindexFBBHLast;
  CBlockIndex* FindBlockByHeight(int nHeight)
  {
      CBlockIndex *pblockindex;
      if (nHeight < nBestHeight / 2)
          pblockindex = pindexGenesisBlock;
      else
          pblockindex = pindexBest;
      if (pblockindexFBBHLast && abs(nHeight - pblockindex->nHeight) > abs(nHeight - pblockindexFBBHLast->nHeight))
          pblockindex = pblockindexFBBHLast;
      while (pblockindex->nHeight > nHeight)
          pblockindex = pblockindex->pprev;
      while (pblockindex->nHeight < nHeight)
          pblockindex = pblockindex->pnext;
      pblockindexFBBHLast = pblockindex;
      return pblockindex;
  }
  
  
  bool CBlock::ReadFromDisk(const CBlockIndex* pindex, bool fReadTransactions)
  {
      if (!fReadTransactions)
      {
          *this = pindex->GetBlockHeader();
          return true;
      }
      if (!ReadFromDisk(pindex->nFile, pindex->nBlockPos, fReadTransactions))
          return false;
      if (GetHash() != pindex->GetBlockHash())
          return error("CBlock::ReadFromDisk() : GetHash() doesn't match index");
      return true;
  }
  
  
  uint256 static GetOrphanRoot(const CBlock* pblock)
  {
      // Work back to the first block in the orphan chain
      while (mapOrphanBlocks.count(pblock->hashPrevBlock))
          pblock = mapOrphanBlocks[pblock->hashPrevBlock];
      return pblock->GetHash();
  }
  
  
  // ppcoin: find block wanted by given orphan block
  uint256 WantedByOrphan(const CBlock* pblockOrphan)
  {
      // Work back to the first block in the orphan chain
      while (mapOrphanBlocks.count(pblockOrphan->hashPrevBlock))
          pblockOrphan = mapOrphanBlocks[pblockOrphan->hashPrevBlock];
      return pblockOrphan->hashPrevBlock;
  }
  
  
  int generateMTRandom(unsigned int s, int range)
  {
  	random::mt19937 gen(s);
      random::uniform_int_distribution<> dist(0, range);
      return dist(gen);
  }
  
  static int FINAL_POW_HEIGHT = 2108986;
  static int FINAL_POW_COUNT = 590000;
  int GetPowHeight(const CBlockIndex* pindex)
  {
  	if(NULL == pindex) return 0;
  
  	int count = 0;
  	int height = pindex->nHeight;
  	int maxCheck = height;
  	int index = -1;
  //	const CBlockIndex* pindex0 = pindex;
  
  	if(height > FINAL_POW_HEIGHT)
  		return FINAL_POW_COUNT;
  
  	if(NUM_OF_POW_CHECKPOINT != 0)
  	{
  		for(int i = 1; i <= NUM_OF_POW_CHECKPOINT; i++)
  		{
  			if(height > checkpointPoWHeight[NUM_OF_POW_CHECKPOINT - i][0])
  			{
  				index = NUM_OF_POW_CHECKPOINT - i;
  				break;
  			}
  		}
  	}
  
  	if(index != -1)
  		maxCheck = height - checkpointPoWHeight[index][0];
  
      for(int j = 0; j < maxCheck; j++)
  	{
  		if(!pindex->IsProofOfStake())
  			++count;
  
          pindex = pindex->pprev;
  	}
  
  	if(index != -1)
  		count += checkpointPoWHeight[index][1];
  	else
  		++count;
  
  	// printf(">> Height = %d, Count = %d\n", height, count);
      return count;
  }
  
  
  int GetPosHeight(const CBlockIndex* pindex)
  {
  	int posH = pindex->nHeight - GetPowHeight(pindex);
  	return posH;
  }
  
  
  static const int64 nMinSubsidy = 0 * COIN;
  // miner's coin base reward based on nBits
  int64 GetProofOfWorkReward(int nHeight, int64 nFees, uint256 prevHash)
  {
      int64_t nSubsidy = 0 * COIN;
      return nSubsidy + nFees;
  
  }
  
  
  int64 GetProofOfWorkReward(int nHeight, int64 nFees, const CBlockIndex* pindex)
  {
       int nPoWHeight = 0;
       int64_t nSubsidy = 0 * COIN;
     
  
       if(nHeight > 1)
         nPoWHeight = GetPowHeight(pindex);
       else 
         nPoWHeight = nHeight;
  
  
       if (nPoWHeight == 1)
         nSubsidy = 400000000 * COIN; //Premin: 88M
       //no pow coin will be created
  
       return nSubsidy + nFees;
  
  }
  
  
  // miner's coin stake reward based on nBits and coin age spent (coin-days)
  // simple algorithm, not depend on the diff
  static const int YEARLY_POS_BLOCK_COUNT = 1440 * 365;
  int64 GetProofOfStakeReward(int64 nCoinAge, unsigned int nBits, unsigned int nTime, int nHeight)
  {
      int64 nRewardCoinYear;
      nRewardCoinYear = MAX_CLOAK_PROOF_OF_STAKE;
      int64 nSubsidy = nCoinAge * nRewardCoinYear / 365;  //2%
  
      if(nHeight < YEARLY_POS_BLOCK_COUNT * 4)            //1%
        nSubsidy /= 2;
      else
        nSubsidy = 0;
  
      if (fDebug && GetBoolArg("-printcreation"))
          printf("GetProofOfStakeReward(): create=%s nCoinAge=%"PRI64d" nBits=%d\n", FormatMoney(nSubsidy).c_str(), nCoinAge, nBits);
  
      return nSubsidy;
  }
  
  static const int64 nTargetTimespan = 60 * 20; // 20 blocks  
  static const int64 nTargetSpacingWorkMax = 3 * nStakeTargetSpacing; 
  
  //
  // maximum nBits value could possible be required nTime after
  // minimum proof-of-work required was nBase
  //
  unsigned int ComputeMaxBits(CBigNum bnTargetLimit, unsigned int nBase, int64 nTime)
  {
      CBigNum bnResult;
      bnResult.SetCompact(nBase);
      bnResult *= 2;
      while (nTime > 0 && bnResult < bnTargetLimit)
      {
          // Maximum 200% adjustment per day...
          bnResult *= 2;
          nTime -= 24 * 60 * 60;
      }
      if (bnResult > bnTargetLimit)
          bnResult = bnTargetLimit;
      return bnResult.GetCompact();
  }
  
  //
  // minimum amount of work that could possibly be required nTime after
  // minimum proof-of-work required was nBase
  //
  unsigned int ComputeMinWork(unsigned int nBase, int64 nTime)
  {
      return ComputeMaxBits(bnProofOfWorkLimit, nBase, nTime);
  }
  
  //
  // minimum amount of stake that could possibly be required nTime after
  // minimum proof-of-stake required was nBase
  //
  unsigned int ComputeMinStake(unsigned int nBase, int64 nTime, unsigned int nBlockTime)
  {
      return ComputeMaxBits(bnProofOfStakeLimit, nBase, nTime);
  }
  
  
  // ppcoin: find last block index up to pindex
  const CBlockIndex* GetLastBlockIndex(const CBlockIndex* pindex, bool fProofOfStake)
  {
      while (pindex && pindex->pprev && (pindex->IsProofOfStake() != fProofOfStake))
          pindex = pindex->pprev;
      return pindex;
  }
  
  unsigned int GetNextTargetRequired(const CBlockIndex* pindexLast, bool fProofOfStake) 
  {
      CBigNum bnTargetLimit = bnProofOfWorkLimit;
  
      if(fProofOfStake)
      {
          // Proof-of-Stake blocks has own target limit since nVersion=3 supermajority on mainNet and always on testNet
          bnTargetLimit = bnProofOfStakeLimit;
      }
  
      if (pindexLast == NULL)
          return bnTargetLimit.GetCompact(); // genesis block
  
      const CBlockIndex* pindexPrev = GetLastBlockIndex(pindexLast, fProofOfStake);
      if (pindexPrev->pprev == NULL)
          return bnTargetLimit.GetCompact(); // first block
      const CBlockIndex* pindexPrevPrev = GetLastBlockIndex(pindexPrev->pprev, fProofOfStake);
      if (pindexPrevPrev->pprev == NULL)
          return bnTargetLimit.GetCompact(); // second block
  
      int64 nActualSpacing = pindexPrev->GetBlockTime() - pindexPrevPrev->GetBlockTime();
  	if(nActualSpacing < 0)
  	{
  		// printf(">> nActualSpacing = %"PRI64d" corrected to 1.\n", nActualSpacing);
  		nActualSpacing = 1;
  	}
  	else if(nActualSpacing > nTargetTimespan)
  	{
  		// printf(">> nActualSpacing = %"PRI64d" corrected to nTargetTimespan (900).\n", nActualSpacing);
  		nActualSpacing = nTargetTimespan;
  	}
  
      // ppcoin: target change every block
      // ppcoin: retarget with exponential moving toward target spacing
      CBigNum bnNew;
      bnNew.SetCompact(pindexPrev->nBits);
  
      int64 nTargetSpacing = fProofOfStake? nStakeTargetSpacing : min(nTargetSpacingWorkMax, (int64) nStakeTargetSpacing * (1 + pindexLast->nHeight - pindexPrev->nHeight));
      int64 nInterval = nTargetTimespan / nTargetSpacing;
      bnNew *= ((nInterval - 1) * nTargetSpacing + nActualSpacing + nActualSpacing);
      bnNew /= ((nInterval + 1) * nTargetSpacing);
  	
  	/*
  	printf(">> Height = %d, fProofOfStake = %d, nInterval = %"PRI64d", nTargetSpacing = %"PRI64d", nActualSpacing = %"PRI64d"\n", 
  		pindexPrev->nHeight, fProofOfStake, nInterval, nTargetSpacing, nActualSpacing);  
  	printf(">> pindexPrev->GetBlockTime() = %"PRI64d", pindexPrev->nHeight = %d, pindexPrevPrev->GetBlockTime() = %"PRI64d", pindexPrevPrev->nHeight = %d\n", 
  		pindexPrev->GetBlockTime(), pindexPrev->nHeight, pindexPrevPrev->GetBlockTime(), pindexPrevPrev->nHeight);  
  	*/
  
      if (bnNew > bnTargetLimit)
          bnNew = bnTargetLimit;
  
      return bnNew.GetCompact();
  }
  
  bool CheckProofOfWork(uint256 hash, unsigned int nBits)
  {
      CBigNum bnTarget;
      bnTarget.SetCompact(nBits);
  
      // Check range
      if (bnTarget <= 0 || bnTarget > bnProofOfWorkLimit)
          return error("CheckProofOfWork() : nBits below minimum work");
  
      // Check proof of work matches claimed amount
      if (hash > bnTarget.getuint256())
          return error("CheckProofOfWork() : hash doesn't match nBits");
  
      return true;
  }
  
  // Return maximum amount of blocks that other nodes claim to have
  int GetNumBlocksOfPeers()
  {
      return std::max(cPeerBlockCounts.median(), Checkpoints::GetTotalBlocksEstimate());
  }
  
  bool IsInitialBlockDownload()
  {
      if (pindexBest == NULL || nBestHeight < Checkpoints::GetTotalBlocksEstimate())
          return true;
      static int64 nLastUpdate;
      static CBlockIndex* pindexLastBest;
      if (pindexBest != pindexLastBest)
      {
          pindexLastBest = pindexBest;
          nLastUpdate = GetTime();
      }
      return (GetTime() - nLastUpdate < 10 &&
              pindexBest->GetBlockTime() < GetTime() - 24 * 60 * 60);
  }
  
  void static InvalidChainFound(CBlockIndex* pindexNew)
  {
      if (pindexNew->bnChainTrust > bnBestInvalidTrust)
      {
          bnBestInvalidTrust = pindexNew->bnChainTrust;
          CTxDB().WriteBestInvalidTrust(bnBestInvalidTrust);
          uiInterface.NotifyBlocksChanged();
      }
  
      printf("InvalidChainFound: invalid block=%s  height=%d  trust=%s  date=%s\n",
        pindexNew->GetBlockHash().ToString().substr(0,20).c_str(), pindexNew->nHeight,
        pindexNew->bnChainTrust.ToString().c_str(), DateTimeStrFormat("%x %H:%M:%S",
        pindexNew->GetBlockTime()).c_str());
      printf("InvalidChainFound:  current best=%s  height=%d  trust=%s  date=%s\n",
        hashBestChain.ToString().substr(0,20).c_str(), nBestHeight, bnBestChainTrust.ToString().c_str(),
        DateTimeStrFormat("%x %H:%M:%S", pindexBest->GetBlockTime()).c_str());
  }
  
  void CBlock::UpdateTime(const CBlockIndex* pindexPrev)
  {
      nTime = max(GetBlockTime(), GetAdjustedTime());
  }
  
  
  bool CTransaction::DisconnectInputs(CTxDB& txdb)
  {
      // Relinquish previous transactions' spent pointers
      if (!IsCoinBase())
      {
          BOOST_FOREACH(const CTxIn& txin, vin)
          {
              COutPoint prevout = txin.prevout;
  
              // Get prev txindex from disk
              CTxIndex txindex;
              if (!txdb.ReadTxIndex(prevout.hash, txindex))
                  return error("DisconnectInputs() : ReadTxIndex failed");
  
              if (prevout.n >= txindex.vSpent.size())
                  return error("DisconnectInputs() : prevout.n out of range");
  
              // Mark outpoint as not spent
              txindex.vSpent[prevout.n].SetNull();
  
              // Write back
              if (!txdb.UpdateTxIndex(prevout.hash, txindex))
                  return error("DisconnectInputs() : UpdateTxIndex failed");
          }
      }
  
      // Remove transaction from index
      // This can fail if a duplicate of this transaction was in a chain that got
      // reorganized away. This is only possible if this transaction was completely
      // spent, so erasing it would be a no-op anyway.
      txdb.EraseTxIndex(*this);
  
      return true;
  }
  
  
  bool CTransaction::FetchInputs(CTxDB& txdb, const map<uint256, CTxIndex>& mapTestPool,
                                 bool fBlock, bool fMiner, MapPrevTx& inputsRet, bool& fInvalid)
  {
      // FetchInputs can return false either because we just haven't seen some inputs
      // (in which case the transaction should be stored as an orphan)
      // or because the transaction is malformed (in which case the transaction should
      // be dropped).  If tx is definitely invalid, fInvalid will be set to true.
      fInvalid = false;
  
      if (IsCoinBase())
          return true; // Coinbase transactions have no inputs to fetch.
  
      for (unsigned int i = 0; i < vin.size(); i++)
      {
          COutPoint prevout = vin[i].prevout;
          if (inputsRet.count(prevout.hash))
              continue; // Got it already
  
          // Read txindex
          CTxIndex& txindex = inputsRet[prevout.hash].first;
          bool fFound = true;
          if ((fBlock || fMiner) && mapTestPool.count(prevout.hash))
          {
              // Get txindex from current proposed changes
              txindex = mapTestPool.find(prevout.hash)->second;
          }
          else
          {
              // Read txindex from txdb
              fFound = txdb.ReadTxIndex(prevout.hash, txindex);
          }
          if (!fFound && (fBlock || fMiner))
              return fMiner ? false : error("FetchInputs() : %s prev tx %s index entry not found", GetHash().ToString().substr(0,10).c_str(),  prevout.hash.ToString().substr(0,10).c_str());
  
          // Read txPrev
          CTransaction& txPrev = inputsRet[prevout.hash].second;
          if (!fFound || txindex.pos == CDiskTxPos(1,1,1))
          {
              // Get prev tx from single transactions in memory
              {
                  LOCK(mempool.cs);
                  if (!mempool.exists(prevout.hash))
                      return error("FetchInputs() : %s mempool Tx prev not found %s", GetHash().ToString().substr(0,10).c_str(),  prevout.hash.ToString().substr(0,10).c_str());
                  txPrev = mempool.lookup(prevout.hash);
              }
              if (!fFound)
                  txindex.vSpent.resize(txPrev.vout.size());
          }
          else
          {
              // Get prev tx from disk
              if (!txPrev.ReadFromDisk(txindex.pos))
                  return error("FetchInputs() : %s ReadFromDisk prev tx %s failed", GetHash().ToString().substr(0,10).c_str(),  prevout.hash.ToString().substr(0,10).c_str());
          }
      }
  
      // Make sure all prevout.n indexes are valid:
      for (unsigned int i = 0; i < vin.size(); i++)
      {
          const COutPoint prevout = vin[i].prevout;
          assert(inputsRet.count(prevout.hash) != 0);
          const CTxIndex& txindex = inputsRet[prevout.hash].first;
          const CTransaction& txPrev = inputsRet[prevout.hash].second;
          if (prevout.n >= txPrev.vout.size() || prevout.n >= txindex.vSpent.size())
          {
              // Revisit this if/when transaction replacement is implemented and allows
              // adding inputs:
              fInvalid = true;
              return DoS(100, error("FetchInputs() : %s prevout.n out of range %d %"PRIszu" %"PRIszu" prev tx %s\n%s", GetHash().ToString().substr(0,10).c_str(), prevout.n, txPrev.vout.size(), txindex.vSpent.size(), prevout.hash.ToString().substr(0,10).c_str(), txPrev.ToString().c_str()));
          }
      }
  
      return true;
  }
  
  
  const CTxOut& CTransaction::GetOutputFor(const CTxIn& input, const MapPrevTx& inputs) const
  {
      MapPrevTx::const_iterator mi = inputs.find(input.prevout.hash);
      if (mi == inputs.end())
          throw std::runtime_error("CTransaction::GetOutputFor() : prevout.hash not found");
  
      const CTransaction& txPrev = (mi->second).second;
      if (input.prevout.n >= txPrev.vout.size())
          throw std::runtime_error("CTransaction::GetOutputFor() : prevout.n out of range");
  
      return txPrev.vout[input.prevout.n];
  }
  
  
  int64 CTransaction::GetValueIn(const MapPrevTx& inputs) const
  {
      if (IsCoinBase())
          return 0;
  
      int64 nResult = 0;
      for (unsigned int i = 0; i < vin.size(); i++)
      {
          nResult += GetOutputFor(vin[i], inputs).nValue;
      }
      return nResult;
  
  }
  
  
  unsigned int CTransaction::GetP2SHSigOpCount(const MapPrevTx& inputs) const
  {
      if (IsCoinBase())
          return 0;
  
      unsigned int nSigOps = 0;
      for (unsigned int i = 0; i < vin.size(); i++)
      {
          const CTxOut& prevout = GetOutputFor(vin[i], inputs);
          if (prevout.scriptPubKey.IsPayToScriptHash())
              nSigOps += prevout.scriptPubKey.GetSigOpCount(vin[i].scriptSig);
      }
      return nSigOps;
  }
  
  
  bool CTransaction::ConnectInputs(CTxDB& txdb, MapPrevTx inputs,
                                   map<uint256, CTxIndex>& mapTestPool, const CDiskTxPos& posThisTx,
                                   const CBlockIndex* pindexBlock, bool fBlock, bool fMiner, bool fStrictPayToScriptHash)
  {
      // Take over previous transactions' spent pointers
      // fBlock is true when this is called from AcceptBlock when a new best-block is added to the blockchain
      // fMiner is true when called from the internal bitcoin miner
      // ... both are false when called from CTransaction::AcceptToMemoryPool
      if (!IsCoinBase())
      {
          int64 nValueIn = 0;
          int64 nFees = 0;
          for (unsigned int i = 0; i < vin.size(); i++)
          {
              COutPoint prevout = vin[i].prevout;
              assert(inputs.count(prevout.hash) > 0);
              CTxIndex& txindex = inputs[prevout.hash].first;
              CTransaction& txPrev = inputs[prevout.hash].second;
  
              if (prevout.n >= txPrev.vout.size() || prevout.n >= txindex.vSpent.size())
                  return DoS(100, error("ConnectInputs() : %s prevout.n out of range %d %"PRIszu" %"PRIszu" prev tx %s\n%s", GetHash().ToString().substr(0,10).c_str(), prevout.n, txPrev.vout.size(), txindex.vSpent.size(), prevout.hash.ToString().substr(0,10).c_str(), txPrev.ToString().c_str()));
  
              // If prev is coinbase or coinstake, check that it's matured
              if (txPrev.IsCoinBase() || txPrev.IsCoinStake())
                  for (const CBlockIndex* pindex = pindexBlock; pindex && pindexBlock->nHeight - pindex->nHeight < nCoinbaseMaturity; pindex = pindex->pprev)
                      if (pindex->nBlockPos == txindex.pos.nBlockPos && pindex->nFile == txindex.pos.nFile)
                          return error("ConnectInputs() : tried to spend %s at depth %d", txPrev.IsCoinBase() ? "coinbase" : "coinstake", pindexBlock->nHeight - pindex->nHeight);
  
              // ppcoin: check transaction timestamp
              if (txPrev.nTime > nTime)
                  return DoS(100, error("ConnectInputs() : transaction timestamp earlier than input transaction"));
  
              // Check for negative or overflow input values
              nValueIn += txPrev.vout[prevout.n].nValue;
              if (!MoneyRange(txPrev.vout[prevout.n].nValue) || !MoneyRange(nValueIn))
                  return DoS(100, error("ConnectInputs() : txin values out of range"));
  
          }
          // The first loop above does all the inexpensive checks.
          // Only if ALL inputs pass do we perform expensive ECDSA signature checks.
          // Helps prevent CPU exhaustion attacks.
          for (unsigned int i = 0; i < vin.size(); i++)
          {
              COutPoint prevout = vin[i].prevout;
              assert(inputs.count(prevout.hash) > 0);
              CTxIndex& txindex = inputs[prevout.hash].first;
              CTransaction& txPrev = inputs[prevout.hash].second;
  
              // Check for conflicts (double-spend)
              // This doesn't trigger the DoS code on purpose; if it did, it would make it easier
              // for an attacker to attempt to split the network.
              if (!txindex.vSpent[prevout.n].IsNull())
                  return fMiner ? false : error("ConnectInputs() : %s prev tx already used at %s", GetHash().ToString().substr(0,10).c_str(), txindex.vSpent[prevout.n].ToString().c_str());
  
              // Skip ECDSA signature verification when connecting blocks (fBlock=true)
              // before the last blockchain checkpoint. This is safe because block merkle hashes are
              // still computed and checked, and any change will be caught at the next checkpoint.
              if (!(fBlock && (nBestHeight < Checkpoints::GetTotalBlocksEstimate())))
              {
                  // Verify signature
                  if (!VerifySignature(txPrev, *this, i, fStrictPayToScriptHash, 0))
                  {
                      // only during transition phase for P2SH: do not invoke anti-DoS code for
                      // potentially old clients relaying bad P2SH transactions
                      if (fStrictPayToScriptHash && VerifySignature(txPrev, *this, i, false, 0))
                          return error("ConnectInputs() : %s P2SH VerifySignature failed", GetHash().ToString().substr(0,10).c_str());
  
                      return DoS(100,error("ConnectInputs() : %s VerifySignature failed", GetHash().ToString().substr(0,10).c_str()));
                  }
              }
  
              // Mark outpoints as spent
              txindex.vSpent[prevout.n] = posThisTx;
  
              // Write back
              if (fBlock || fMiner)
              {
                  mapTestPool[prevout.hash] = txindex;
              }
          }
  
          if (IsCoinStake())
          {
              // ppcoin: coin stake tx earns reward instead of paying fee
              uint64 nCoinAge;
              if (!GetCoinAge(txdb, nCoinAge))
                  return error("ConnectInputs() : %s unable to get coin age for coinstake", GetHash().ToString().substr(0,10).c_str());
              int64 nStakeReward = GetValueOut() - nValueIn;
              if (nStakeReward > GetProofOfStakeReward(nCoinAge, pindexBlock->nBits, nTime, pindexBlock->nHeight) - GetMinFee() + MIN_TX_FEE)
                  return DoS(100, error("ConnectInputs() : %s stake reward exceeded", GetHash().ToString().substr(0,10).c_str()));
          }
          else
          {
              if (nValueIn < GetValueOut())
                  return DoS(100, error("ConnectInputs() : %s value in < value out", GetHash().ToString().substr(0,10).c_str()));
  
              // Tally transaction fees
              int64 nTxFee = nValueIn - GetValueOut();
              if (nTxFee < 0)
                  return DoS(100, error("ConnectInputs() : %s nTxFee < 0", GetHash().ToString().substr(0,10).c_str()));
              // ppcoin: enforce transaction fees for every block
              if (nTxFee < GetMinFee())
                  return fBlock? DoS(100, error("ConnectInputs() : %s not paying required fee=%s, paid=%s", GetHash().ToString().substr(0,10).c_str(), FormatMoney(GetMinFee()).c_str(), FormatMoney(nTxFee).c_str())) : false;
  
              nFees += nTxFee;
              if (!MoneyRange(nFees))
                  return DoS(100, error("ConnectInputs() : nFees out of range"));
          }
      }
  
      return true;
  }
  
  
  bool CTransaction::ClientConnectInputs()
  {
      if (IsCoinBase())
          return false;
  
      // Take over previous transactions' spent pointers
      {
          LOCK(mempool.cs);
          int64 nValueIn = 0;
          for (unsigned int i = 0; i < vin.size(); i++)
          {
              // Get prev tx from single transactions in memory
              COutPoint prevout = vin[i].prevout;
              if (!mempool.exists(prevout.hash))
                  return false;
              CTransaction& txPrev = mempool.lookup(prevout.hash);
  
              if (prevout.n >= txPrev.vout.size())
                  return false;
  
              // Verify signature
              if (!VerifySignature(txPrev, *this, i, true, 0))
                  return error("ConnectInputs() : VerifySignature failed");
  
              ///// this is redundant with the mempool.mapNextTx stuff,
              ///// not sure which I want to get rid of
              ///// this has to go away now that posNext is gone
              // // Check for conflicts
              // if (!txPrev.vout[prevout.n].posNext.IsNull())
              //     return error("ConnectInputs() : prev tx already used");
              //
              // // Flag outpoints as used
              // txPrev.vout[prevout.n].posNext = posThisTx;
  
              nValueIn += txPrev.vout[prevout.n].nValue;
  
              if (!MoneyRange(txPrev.vout[prevout.n].nValue) || !MoneyRange(nValueIn))
                  return error("ClientConnectInputs() : txin values out of range");
          }
          if (GetValueOut() > nValueIn)
              return false;
      }
  
      return true;
  }
  
  
  bool CBlock::DisconnectBlock(CTxDB& txdb, CBlockIndex* pindex)
  {
      // Disconnect in reverse order
      for (int i = vtx.size()-1; i >= 0; i--)
          if (!vtx[i].DisconnectInputs(txdb))
              return false;
  
      // Update block index on disk without changing it in memory.
      // The memory index structure will be changed after the db commits.
      if (pindex->pprev)
      {
          CDiskBlockIndex blockindexPrev(pindex->pprev);
          blockindexPrev.hashNext = 0;
          if (!txdb.WriteBlockIndex(blockindexPrev))
              return error("DisconnectBlock() : WriteBlockIndex failed");
      }
  
      // ppcoin: clean up wallet after disconnecting coinstake
      BOOST_FOREACH(CTransaction& tx, vtx)
          SyncWithWallets(tx, this, false, false);
  
      return true;
  }
  
  bool CBlock::ConnectBlock(CTxDB& txdb, CBlockIndex* pindex, bool fJustCheck)
  {
      // Check it again in case a previous version let a bad block in
      if (!CheckBlock(!fJustCheck, !fJustCheck))
          return false;
  
      // Do not allow blocks that contain transactions which 'overwrite' older transactions,
      // unless those are already completely spent.
      // If such overwrites are allowed, coinbases and transactions depending upon those
      // can be duplicated to remove the ability to spend the first instance -- even after
      // being sent to another address.
      // See BIP30 and http://r6.ca/blog/20120206T005236Z.html for more information.
      // This logic is not necessary for memory pool transactions, as AcceptToMemoryPool
      // already refuses previously-known transaction ids entirely.
      // This rule was originally applied all blocks whose timestamp was after March 15, 2012, 0:00 UTC.
      // Now that the whole chain is irreversibly beyond that time it is applied to all blocks except the
      // two in the chain that violate it. This prevents exploiting the issue against nodes in their
      // initial block download.
      bool fEnforceBIP30 = true; // Always active in OfferlibationCoin
      bool fStrictPayToScriptHash = true; // Always active in OfferlibationCoin
  
      //// issue here: it doesn't know the version
      unsigned int nTxPos;
      if (fJustCheck)
          // FetchInputs treats CDiskTxPos(1,1,1) as a special "refer to memorypool" indicator
          // Since we're just checking the block and not actually connecting it, it might not (and probably shouldn't) be on the disk to get the transaction from
          nTxPos = 1;
      else
          nTxPos = pindex->nBlockPos + ::GetSerializeSize(CBlock(), SER_DISK, CLIENT_VERSION) - (2 * GetSizeOfCompactSize(0)) + GetSizeOfCompactSize(vtx.size());
  
      map<uint256, CTxIndex> mapQueuedChanges;
      int64 nFees = 0;
      int64 nValueIn = 0;
      int64 nValueOut = 0;
      unsigned int nSigOps = 0;
      BOOST_FOREACH(CTransaction& tx, vtx)
      {
          uint256 hashTx = tx.GetHash();
  
          if (fEnforceBIP30) {
              CTxIndex txindexOld;
              if (txdb.ReadTxIndex(hashTx, txindexOld)) {
                  BOOST_FOREACH(CDiskTxPos &pos, txindexOld.vSpent)
                      if (pos.IsNull())
                          return false;
              }
          }
  
          nSigOps += tx.GetLegacySigOpCount();
          if (nSigOps > MAX_BLOCK_SIGOPS)
              return DoS(100, error("ConnectBlock() : too many sigops"));
  
          CDiskTxPos posThisTx(pindex->nFile, pindex->nBlockPos, nTxPos);
          if (!fJustCheck)
              nTxPos += ::GetSerializeSize(tx, SER_DISK, CLIENT_VERSION);
  
          MapPrevTx mapInputs;
          if (tx.IsCoinBase())
              nValueOut += tx.GetValueOut();
          else
          {
              bool fInvalid;
              if (!tx.FetchInputs(txdb, mapQueuedChanges, true, false, mapInputs, fInvalid))
                  return false;
  
              if (fStrictPayToScriptHash)
              {
                  // Add in sigops done by pay-to-script-hash inputs;
                  // this is to prevent a "rogue miner" from creating
                  // an incredibly-expensive-to-validate block.
                  nSigOps += tx.GetP2SHSigOpCount(mapInputs);
                  if (nSigOps > MAX_BLOCK_SIGOPS)
                      return DoS(100, error("ConnectBlock() : too many sigops"));
              }
  
              int64 nTxValueIn = tx.GetValueIn(mapInputs);
              int64 nTxValueOut = tx.GetValueOut();
              nValueIn += nTxValueIn;
              nValueOut += nTxValueOut;
              if (!tx.IsCoinStake())
                  nFees += nTxValueIn - nTxValueOut;
  
              if (!tx.ConnectInputs(txdb, mapInputs, mapQueuedChanges, posThisTx, pindex, true, false, fStrictPayToScriptHash))
                  return false;
          }
  
          mapQueuedChanges[hashTx] = CTxIndex(posThisTx, tx.vout.size());
      }
  
      // ppcoin: track money supply and mint amount info
      pindex->nMint = nValueOut - nValueIn + nFees;
      pindex->nMoneySupply = (pindex->pprev? pindex->pprev->nMoneySupply : 0) + nValueOut - nValueIn;
      if (!txdb.WriteBlockIndex(CDiskBlockIndex(pindex)))
          return error("Connect() : WriteBlockIndex for pindex failed");
  
      // ppcoin: fees are not collected by miners as in bitcoin
      // ppcoin: fees are destroyed to compensate the entire network
      if (fDebug && GetBoolArg("-printcreation"))
          printf("ConnectBlock() : destroy=%s nFees=%"PRI64d"\n", FormatMoney(nFees).c_str(), nFees);
  
      if (fJustCheck)
          return true;
  
      // Write queued txindex changes
      for (map<uint256, CTxIndex>::iterator mi = mapQueuedChanges.begin(); mi != mapQueuedChanges.end(); ++mi)
      {
          if (!txdb.UpdateTxIndex((*mi).first, (*mi).second))
              return error("ConnectBlock() : UpdateTxIndex failed");
      }
  
  	uint256 prevHash = 0;
  	if(pindex->pprev)
  	{
  		prevHash = pindex->pprev->GetBlockHash();
  		// printf("==> Got prevHash = %s\n", prevHash.ToString().c_str());
  	}
  
  	if (vtx[0].GetValueOut() > GetProofOfWorkReward(pindex->nHeight, nFees, pindex->pprev))
  		return false;
  
      // Update block index on disk without changing it in memory.
      // The memory index structure will be changed after the db commits.
      if (pindex->pprev)
      {
          CDiskBlockIndex blockindexPrev(pindex->pprev);
          blockindexPrev.hashNext = pindex->GetBlockHash();
          if (!txdb.WriteBlockIndex(blockindexPrev))
              return error("ConnectBlock() : WriteBlockIndex failed");
      }
  
      // Watch for transactions paying to me
      BOOST_FOREACH(CTransaction& tx, vtx)
          SyncWithWallets(tx, this, true);
  
      return true;
  }
  
  bool static Reorganize(CTxDB& txdb, CBlockIndex* pindexNew)
  {
      printf("REORGANIZE\n");
  
      // Find the fork
      CBlockIndex* pfork = pindexBest;
      CBlockIndex* plonger = pindexNew;
      while (pfork != plonger)
      {
          while (plonger->nHeight > pfork->nHeight)
              if (!(plonger = plonger->pprev))
                  return error("Reorganize() : plonger->pprev is null");
          if (pfork == plonger)
              break;
          if (!(pfork = pfork->pprev))
              return error("Reorganize() : pfork->pprev is null");
      }
  
      // List of what to disconnect
      vector<CBlockIndex*> vDisconnect;
      for (CBlockIndex* pindex = pindexBest; pindex != pfork; pindex = pindex->pprev)
          vDisconnect.push_back(pindex);
  
      // List of what to connect
      vector<CBlockIndex*> vConnect;
      for (CBlockIndex* pindex = pindexNew; pindex != pfork; pindex = pindex->pprev)
          vConnect.push_back(pindex);
      reverse(vConnect.begin(), vConnect.end());
  
      printf("REORGANIZE: Disconnect %"PRIszu" blocks; %s..%s\n", vDisconnect.size(), pfork->GetBlockHash().ToString().substr(0,20).c_str(), pindexBest->GetBlockHash().ToString().substr(0,20).c_str());
      printf("REORGANIZE: Connect %"PRIszu" blocks; %s..%s\n", vConnect.size(), pfork->GetBlockHash().ToString().substr(0,20).c_str(), pindexNew->GetBlockHash().ToString().substr(0,20).c_str());
  
      // Disconnect shorter branch
      vector<CTransaction> vResurrect;
      BOOST_FOREACH(CBlockIndex* pindex, vDisconnect)
      {
          CBlock block;
          if (!block.ReadFromDisk(pindex))
              return error("Reorganize() : ReadFromDisk for disconnect failed");
          if (!block.DisconnectBlock(txdb, pindex))
              return error("Reorganize() : DisconnectBlock %s failed", pindex->GetBlockHash().ToString().substr(0,20).c_str());
  
          // Queue memory transactions to resurrect
          BOOST_FOREACH(const CTransaction& tx, block.vtx)
              if (!(tx.IsCoinBase() || tx.IsCoinStake()))
                  vResurrect.push_back(tx);
      }
  
      // Connect longer branch
      vector<CTransaction> vDelete;
      for (unsigned int i = 0; i < vConnect.size(); i++)
      {
          CBlockIndex* pindex = vConnect[i];
          CBlock block;
          if (!block.ReadFromDisk(pindex))
              return error("Reorganize() : ReadFromDisk for connect failed");
          if (!block.ConnectBlock(txdb, pindex))
          {
              // Invalid block
              return error("Reorganize() : ConnectBlock %s failed", pindex->GetBlockHash().ToString().substr(0,20).c_str());
          }
  
          // Queue memory transactions to delete
          BOOST_FOREACH(const CTransaction& tx, block.vtx)
              vDelete.push_back(tx);
      }
      if (!txdb.WriteHashBestChain(pindexNew->GetBlockHash()))
          return error("Reorganize() : WriteHashBestChain failed");
  
      // Make sure it's successfully written to disk before changing memory structure
      if (!txdb.TxnCommit())
          return error("Reorganize() : TxnCommit failed");
  
      // Disconnect shorter branch
      BOOST_FOREACH(CBlockIndex* pindex, vDisconnect)
          if (pindex->pprev)
              pindex->pprev->pnext = NULL;
  
      // Connect longer branch
      BOOST_FOREACH(CBlockIndex* pindex, vConnect)
          if (pindex->pprev)
              pindex->pprev->pnext = pindex;
  
      // Resurrect memory transactions that were in the disconnected branch
      BOOST_FOREACH(CTransaction& tx, vResurrect)
          tx.AcceptToMemoryPool(txdb, false);
  
      // Delete redundant memory transactions that are in the connected branch
      BOOST_FOREACH(CTransaction& tx, vDelete)
          mempool.remove(tx);
  
      printf("REORGANIZE: done\n");
  
      return true;
  }
  
  
  // Called from inside SetBestChain: attaches a block to the new best chain being built
  bool CBlock::SetBestChainInner(CTxDB& txdb, CBlockIndex *pindexNew)
  {
      uint256 hash = GetHash();
  
      // Adding to current best branch
      if (!ConnectBlock(txdb, pindexNew) || !txdb.WriteHashBestChain(hash))
      {
          txdb.TxnAbort();
          InvalidChainFound(pindexNew);
          return false;
      }
      if (!txdb.TxnCommit())
          return error("SetBestChain() : TxnCommit failed");
  
      // Add to current best branch
      pindexNew->pprev->pnext = pindexNew;
  
      // Delete redundant memory transactions
      BOOST_FOREACH(CTransaction& tx, vtx)
          mempool.remove(tx);
  
      return true;
  }
  
  
  bool CBlock::SetBestChain(CTxDB& txdb, CBlockIndex* pindexNew)
  {
      uint256 hash = GetHash();
  
      if (!txdb.TxnBegin())
          return error("SetBestChain() : TxnBegin failed");
  
      if (pindexGenesisBlock == NULL && hash == (!fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet))
      {
          txdb.WriteHashBestChain(hash);
          if (!txdb.TxnCommit())
              return error("SetBestChain() : TxnCommit failed");
          pindexGenesisBlock = pindexNew;
      }
      else if (hashPrevBlock == hashBestChain)
      {
          if (!SetBestChainInner(txdb, pindexNew))
              return error("SetBestChain() : SetBestChainInner failed");
      }
      else
      {
          // the first block in the new chain that will cause it to become the new best chain
          CBlockIndex *pindexIntermediate = pindexNew;
  
          // list of blocks that need to be connected afterwards
          std::vector<CBlockIndex*> vpindexSecondary;
  
          // Reorganize is costly in terms of db load, as it works in a single db transaction.
          // Try to limit how much needs to be done inside
          while (pindexIntermediate->pprev && pindexIntermediate->pprev->bnChainTrust > pindexBest->bnChainTrust)
          {
              vpindexSecondary.push_back(pindexIntermediate);
              pindexIntermediate = pindexIntermediate->pprev;
          }
  
          if (!vpindexSecondary.empty())
              printf("Postponing %"PRIszu" reconnects\n", vpindexSecondary.size());
  
          // Switch to new best branch
          if (!Reorganize(txdb, pindexIntermediate))
          {
              txdb.TxnAbort();
              InvalidChainFound(pindexNew);
              return error("SetBestChain() : Reorganize failed");
          }
  
          // Connect further blocks
          BOOST_REVERSE_FOREACH(CBlockIndex *pindex, vpindexSecondary)
          {
              CBlock block;
              if (!block.ReadFromDisk(pindex))
              {
                  printf("SetBestChain() : ReadFromDisk failed\n");
                  break;
              }
              if (!txdb.TxnBegin()) {
                  printf("SetBestChain() : TxnBegin 2 failed\n");
                  break;
              }
              // errors now are not fatal, we still did a reorganisation to a new chain in a valid way
              if (!block.SetBestChainInner(txdb, pindex))
                  break;
          }
      }
  
      // Update best block in wallet (so we can detect restored wallets)
      bool fIsInitialDownload = IsInitialBlockDownload();
      if (!fIsInitialDownload)
      {
          const CBlockLocator locator(pindexNew);
          ::SetBestChain(locator);
      }
  
      // New best block
      hashBestChain = hash;
      pindexBest = pindexNew;
      pblockindexFBBHLast = NULL;
      nBestHeight = pindexBest->nHeight;
      bnBestChainTrust = pindexNew->bnChainTrust;
      nTimeBestReceived = GetTime();
      nTransactionsUpdated++;
      printf("SetBestChain: new best=%s  height=%d  trust=%s  date=%s\n",
        hashBestChain.ToString().c_str(), nBestHeight, bnBestChainTrust.ToString().c_str(),
        DateTimeStrFormat("%x %H:%M:%S", pindexBest->GetBlockTime()).c_str());
  
  	printf("Stake checkpoint: %x\n", pindexBest->nStakeModifierChecksum);
  
      // Check the version of the last 100 blocks to see if we need to upgrade:
      if (!fIsInitialDownload)
      {
          int nUpgraded = 0;
          const CBlockIndex* pindex = pindexBest;
          for (int i = 0; i < 100 && pindex != NULL; i++)
          {
              if (pindex->nVersion > CBlock::CURRENT_VERSION)
                  ++nUpgraded;
              pindex = pindex->pprev;
          }
          if (nUpgraded > 0)
              printf("SetBestChain: %d of last 100 blocks above version %d\n", nUpgraded, CBlock::CURRENT_VERSION);
          if (nUpgraded > 100/2)
              // strMiscWarning is read by GetWarnings(), called by Qt and the JSON-RPC code to warn the user:
              strMiscWarning = _("Warning: This version is obsolete, upgrade required!");
      }
  
      std::string strCmd = GetArg("-blocknotify", "");
  
      if (!fIsInitialDownload && !strCmd.empty())
      {
          boost::replace_all(strCmd, "%s", hashBestChain.GetHex());
          boost::thread t(runCommand, strCmd); // thread runs free
      }
  
      return true;
  }
  
  // ppcoin: total coin age spent in transaction, in the unit of coin-days.
  // Only those coins meeting minimum age requirement counts. As those
  // transactions not in main chain are not currently indexed so we
  // might not find out about their coin age. Older transactions are 
  // guaranteed to be in main chain by sync-checkpoint. This rule is
  // introduced to help nodes establish a consistent view of the coin
  // age (trust score) of competing branches.
  bool CTransaction::GetCoinAge(CTxDB& txdb, uint64& nCoinAge) const
  {
      CBigNum bnCentSecond = 0;  // coin age in the unit of cent-seconds
      nCoinAge = 0;
  
      if (IsCoinBase())
          return true;
  
      BOOST_FOREACH(const CTxIn& txin, vin)
      {
          // First try finding the previous transaction in database
          CTransaction txPrev;
          CTxIndex txindex;
          if (!txPrev.ReadFromDisk(txdb, txin.prevout, txindex))
              continue;  // previous transaction not in main chain
          if (nTime < txPrev.nTime)
              return false;  // Transaction timestamp violation
  
          // Read block header
          CBlock block;
          if (!block.ReadFromDisk(txindex.pos.nFile, txindex.pos.nBlockPos, false))
              return false; // unable to read block of previous transaction
          if (block.GetBlockTime() + nStakeMinAge > nTime)
              continue; // only count coins meeting min age requirement
  
          int64 nValueIn = txPrev.vout[txin.prevout.n].nValue;
          bnCentSecond += CBigNum(nValueIn) * (nTime-txPrev.nTime) / CENT;
  
          if (fDebug && GetBoolArg("-printcoinage"))
              printf("coin age nValueIn=%"PRI64d" nTimeDiff=%d bnCentSecond=%s\n", nValueIn, nTime - txPrev.nTime, bnCentSecond.ToString().c_str());
      }
  
      CBigNum bnCoinDay = bnCentSecond * CENT / COIN / (24 * 60 * 60);
      if (fDebug && GetBoolArg("-printcoinage"))
          printf("coin age bnCoinDay=%s\n", bnCoinDay.ToString().c_str());
      nCoinAge = bnCoinDay.getuint64();
      return true;
  }
  
  // ppcoin: total coin age spent in block, in the unit of coin-days.
  bool CBlock::GetCoinAge(uint64& nCoinAge) const
  {
      nCoinAge = 0;
  
      CTxDB txdb("r");
      BOOST_FOREACH(const CTransaction& tx, vtx)
      {
          uint64 nTxCoinAge;
          if (tx.GetCoinAge(txdb, nTxCoinAge))
              nCoinAge += nTxCoinAge;
          else
              return false;
      }
  
      if (nCoinAge == 0) // block coin age minimum 1 coin-day
          nCoinAge = 1;
      if (fDebug && GetBoolArg("-printcoinage"))
          printf("block coin age total nCoinDays=%"PRI64d"\n", nCoinAge);
      return true;
  }
  
  bool CBlock::AddToBlockIndex(unsigned int nFile, unsigned int nBlockPos)
  {
      // Check for duplicate
      uint256 hash = GetHash();
      if (mapBlockIndex.count(hash))
          return error("AddToBlockIndex() : %s already exists", hash.ToString().substr(0,20).c_str());
  
      // Construct new block index object
      CBlockIndex* pindexNew = new CBlockIndex(nFile, nBlockPos, *this);
      if (!pindexNew)
          return error("AddToBlockIndex() : new CBlockIndex failed");
      pindexNew->phashBlock = &hash;
      map<uint256, CBlockIndex*>::iterator miPrev = mapBlockIndex.find(hashPrevBlock);
      if (miPrev != mapBlockIndex.end())
      {
          pindexNew->pprev = (*miPrev).second;
          pindexNew->nHeight = pindexNew->pprev->nHeight + 1;
      }
  
      // ppcoin: compute chain trust score
      pindexNew->bnChainTrust = (pindexNew->pprev ? pindexNew->pprev->bnChainTrust : 0) + pindexNew->GetBlockTrust();
  
      // ppcoin: compute stake entropy bit for stake modifier
      if (!pindexNew->SetStakeEntropyBit(GetStakeEntropyBit(pindexNew->nHeight)))
          return error("AddToBlockIndex() : SetStakeEntropyBit() failed");
  
      // ppcoin: record proof-of-stake hash value
      if (pindexNew->IsProofOfStake())
      {
          if (!mapProofOfStake.count(hash))
              return error("AddToBlockIndex() : hashProofOfStake not found in map");
          pindexNew->hashProofOfStake = mapProofOfStake[hash];
      }
  
      // ppcoin: compute stake modifier
      uint64 nStakeModifier = 0;
      bool fGeneratedStakeModifier = false;
      if (!ComputeNextStakeModifier(pindexNew->pprev, nStakeModifier, fGeneratedStakeModifier))
          return error("AddToBlockIndex() : ComputeNextStakeModifier() failed");
      pindexNew->SetStakeModifier(nStakeModifier, fGeneratedStakeModifier);
      pindexNew->nStakeModifierChecksum = GetStakeModifierChecksum(pindexNew);
      if (!CheckStakeModifierCheckpoints(pindexNew->nHeight, pindexNew->nStakeModifierChecksum))
          return error("AddToBlockIndex() : Rejected by stake modifier checkpoint height=%d, modifier=0x%016"PRI64x, pindexNew->nHeight, nStakeModifier);
  
      // Add to mapBlockIndex
      map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.insert(make_pair(hash, pindexNew)).first;
      if (pindexNew->IsProofOfStake())
          setStakeSeen.insert(make_pair(pindexNew->prevoutStake, pindexNew->nStakeTime));
      pindexNew->phashBlock = &((*mi).first);
  
      // Write to disk block index
      CTxDB txdb;
      if (!txdb.TxnBegin())
          return false;
      txdb.WriteBlockIndex(CDiskBlockIndex(pindexNew));
      if (!txdb.TxnCommit())
          return false;
  
      // New best
      if (pindexNew->bnChainTrust > bnBestChainTrust)
          if (!SetBestChain(txdb, pindexNew))
              return false;
  
      txdb.Close();
  
      if (pindexNew == pindexBest)
      {
          // Notify UI to display prev block's coinbase if it was ours
          static uint256 hashPrevBestCoinBase;
          UpdatedTransaction(hashPrevBestCoinBase);
          hashPrevBestCoinBase = vtx[0].GetHash();
      }
  
      uiInterface.NotifyBlocksChanged();
      return true;
  }
  
  
  bool CBlock::CheckBlock(bool fCheckPOW, bool fCheckMerkleRoot) const
  {
      // These are checks that are independent of context
      // that can be verified before saving an orphan block.
  
      // Size limits
      if (vtx.empty() || vtx.size() > MAX_BLOCK_SIZE || ::GetSerializeSize(*this, SER_NETWORK, PROTOCOL_VERSION) > MAX_BLOCK_SIZE)
          return DoS(100, error("CheckBlock() : size limits failed"));
  
      // Check proof of work matches claimed amount
      if (fCheckPOW && IsProofOfWork() && !CheckProofOfWork(GetHash(), nBits))
          return DoS(50, error("CheckBlock() : proof of work failed"));
  
      // First transaction must be coinbase, the rest must not be
      if (vtx.empty() || !vtx[0].IsCoinBase())
          return DoS(100, error("CheckBlock() : first tx is not coinbase"));
      for (unsigned int i = 1; i < vtx.size(); i++)
          if (vtx[i].IsCoinBase())
              return DoS(100, error("CheckBlock() : more than one coinbase"));
  
      // ppcoin: only the second transaction can be the optional coinstake
      for (unsigned int i = 2; i < vtx.size(); i++)
          if (vtx[i].IsCoinStake())
              return DoS(100, error("CheckBlock() : coinstake in wrong position"));
  
      // ppcoin: coinbase output should be empty if proof-of-stake block
      if (IsProofOfStake() && (vtx[0].vout.size() != 1 || !vtx[0].vout[0].IsEmpty()))
          return error("CheckBlock() : coinbase output not empty for proof-of-stake block");
  
      // Check transactions
      BOOST_FOREACH(const CTransaction& tx, vtx)
      {
          if (!tx.CheckTransaction())
              return DoS(tx.nDoS, error("CheckBlock() : CheckTransaction failed"));
  
          // ppcoin: check transaction timestamp
          if (GetBlockTime() < (int64)tx.nTime)
              return DoS(50, error("CheckBlock() : block timestamp earlier than transaction timestamp"));
      }
  
      // Check for duplicate txids. This is caught by ConnectInputs(),
      // but catching it earlier avoids a potential DoS attack:
      set<uint256> uniqueTx;
      BOOST_FOREACH(const CTransaction& tx, vtx)
      {
          uniqueTx.insert(tx.GetHash());
      }
      if (uniqueTx.size() != vtx.size())
          return DoS(100, error("CheckBlock() : duplicate transaction"));
  
      unsigned int nSigOps = 0;
      BOOST_FOREACH(const CTransaction& tx, vtx)
      {
          nSigOps += tx.GetLegacySigOpCount();
      }
      if (nSigOps > MAX_BLOCK_SIGOPS)
          return DoS(100, error("CheckBlock() : out-of-bounds SigOpCount"));
  
      // Check merkle root
      if (fCheckMerkleRoot && hashMerkleRoot != BuildMerkleTree())
          return DoS(100, error("CheckBlock() : hashMerkleRoot mismatch"));
  
      // ppcoin: check block signature
      if (!CheckBlockSignature())
          return DoS(100, error("CheckBlock() : bad block signature"));
  
      return true;
  }
  
  
  bool CBlock::AcceptBlock()
  {
      // Check for duplicate
      uint256 hash = GetHash();
      if (mapBlockIndex.count(hash))
          return error("AcceptBlock() : block already in mapBlockIndex");
  
      // Get prev block index
      map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hashPrevBlock);
      if (mi == mapBlockIndex.end())
          return DoS(10, error("AcceptBlock() : prev block not found"));
      CBlockIndex* pindexPrev = (*mi).second;
      int nHeight = pindexPrev->nHeight+1;
  
      if (IsProofOfWork() && nHeight > CUTOFF_POW_BLOCK)
          return DoS(100, error("AcceptBlock() : No proof-of-work allowed anymore (height = %d)", nHeight));
  
      // Check proof-of-work or proof-of-stake
      if (nBits != GetNextTargetRequired(pindexPrev, IsProofOfStake()))
          return DoS(100, error("AcceptBlock() : incorrect %s", IsProofOfWork() ? "proof-of-work" : "proof-of-stake"));
  
      // Check timestamp
      if (GetBlockTime() > GetAdjustedTime() + GetMaxClockDrift(nHeight))
          return error("AcceptBlock() : block timestamp too far in the future");
  
      // Check coinbase timestamp
      if (GetBlockTime() > (int64)vtx[0].nTime + GetMaxClockDrift(nHeight))
          return DoS(50, error("AcceptBlock() : coinbase timestamp is too early"));
  
      // Check that all transactions are finalized
      BOOST_FOREACH(const CTransaction& tx, vtx)
          if (!tx.IsFinal(nHeight, GetBlockTime()))
              return DoS(10, error("AcceptBlock() : contains a non-final transaction"));
  
      // Check that the block chain matches the known block chain up to a checkpoint
      if (!Checkpoints::CheckHardened(nHeight, hash))
          return DoS(100, error("AcceptBlock() : rejected by hardened checkpoint lock-in at %d", nHeight));
  
      // ppcoin: check that the block satisfies synchronized checkpoint
      if (!Checkpoints::CheckSync(hash, pindexPrev))
      {
          if(!GetBoolArg("-nosynccheckpoints", false))
          {
              return error("AcceptBlock() : rejected by synchronized checkpoint");
          }
          else
          {
              strMiscWarning = _("WARNING: syncronized checkpoint violation detected, but skipped!");
          }
      }
  
      // Reject block.nVersion < 3 blocks since 95% threshold on mainNet and always on testNet:
      if (nVersion < 3 && ((!fTestNet && nHeight > 14060) || (fTestNet && nHeight > 0)))
          return error("CheckBlock() : rejected nVersion < 3 block");
  
      // Enforce rule that the coinbase starts with serialized block height
      CScript expect = CScript() << nHeight;
      if (!std::equal(expect.begin(), expect.end(), vtx[0].vin[0].scriptSig.begin()))
          return DoS(100, error("AcceptBlock() : block height mismatch in coinbase"));
  
      // Write block to history file
      if (!CheckDiskSpace(::GetSerializeSize(*this, SER_DISK, CLIENT_VERSION)))
          return error("AcceptBlock() : out of disk space");
      unsigned int nFile = -1;
      unsigned int nBlockPos = 0;
      if (!WriteToDisk(nFile, nBlockPos))
          return error("AcceptBlock() : WriteToDisk failed");
      if (!AddToBlockIndex(nFile, nBlockPos))
          return error("AcceptBlock() : AddToBlockIndex failed");
  
      // Relay inventory, but don't relay old inventory during initial block download
      int nBlockEstimate = Checkpoints::GetTotalBlocksEstimate();
      if (hashBestChain == hash)
      {
          LOCK(cs_vNodes);
          BOOST_FOREACH(CNode* pnode, vNodes)
              if (nBestHeight > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate))
                  pnode->PushInventory(CInv(MSG_BLOCK, hash));
      }
  
      // ppcoin: check pending sync-checkpoint
      Checkpoints::AcceptPendingSyncCheckpoint();
  
      return true;
  }
  
  
  CBigNum CBlockIndex::GetBlockTrust() const
  {
      CBigNum bnTarget;
      bnTarget.SetCompact(nBits);
      if (bnTarget <= 0)
          return 0;
  
      if (IsProofOfStake())
      {
          // Return trust score as usual
          return (CBigNum(1)<<256) / (bnTarget+1);
      }
      else
      {
          // Calculate work amount for block
          CBigNum bnPoWTrust = (bnProofOfWorkLimit / (bnTarget+1));
          return bnPoWTrust > 1 ? bnPoWTrust : 1;
      }
  } 
  
  bool CBlockIndex::IsSuperMajority(int minVersion, const CBlockIndex* pstart, unsigned int nRequired, unsigned int nToCheck)
  {
      unsigned int nFound = 0;
      for (unsigned int i = 0; i < nToCheck && nFound < nRequired && pstart != NULL; i++)
      {
          if (pstart->nVersion >= minVersion)
              ++nFound;
          pstart = pstart->pprev;
      }
      return (nFound >= nRequired);
  }
  
  
  bool ProcessBlock(CNode* pfrom, CBlock* pblock)
  {
      // Check for duplicate
      uint256 hash = pblock->GetHash();
      if (mapBlockIndex.count(hash))
          return error("ProcessBlock() : already have block %d %s", mapBlockIndex[hash]->nHeight, hash.ToString().substr(0,20).c_str());
      if (mapOrphanBlocks.count(hash))
          return error("ProcessBlock() : already have block (orphan) %s", hash.ToString().substr(0,20).c_str());
  
      // ppcoin: check proof-of-stake
      // Limited duplicity on stake: prevents block flood attack
      // Duplicate stake allowed only when there is orphan child block
      if (pblock->IsProofOfStake() && setStakeSeen.count(pblock->GetProofOfStake()) && !mapOrphanBlocksByPrev.count(hash) && !Checkpoints::WantedByPendingSyncCheckpoint(hash))
          return error("ProcessBlock() : duplicate proof-of-stake (%s, %d) for block %s", pblock->GetProofOfStake().first.ToString().c_str(), pblock->GetProofOfStake().second, hash.ToString().c_str());
  
      // Preliminary checks
      if (!pblock->CheckBlock())
          return error("ProcessBlock() : CheckBlock FAILED");
  
      // ppcoin: verify hash target and signature of coinstake tx
      if (pblock->IsProofOfStake())
      {
          uint256 hashProofOfStake = 0;
          if (!CheckProofOfStake(pblock->vtx[1], pblock->nBits, hashProofOfStake))
          {
              printf("WARNING: ProcessBlock(): check proof-of-stake failed for block %s\n", hash.ToString().c_str());
              return false; // do not error here as we expect this during initial block download
          }
          if (!mapProofOfStake.count(hash)) // add to mapProofOfStake
              mapProofOfStake.insert(make_pair(hash, hashProofOfStake));
      }
  
      CBlockIndex* pcheckpoint = Checkpoints::GetLastSyncCheckpoint();
  
      if(pcheckpoint && fDebug)
      {
  	const CBlockIndex* pindexLastPos = GetLastBlockIndex(pcheckpoint, true);
          if(pindexLastPos)
  	{
              printf("ProcessBlock(): Last POS Block Height: %d \n", pindexLastPos->nHeight);
  	}
  	else
  	{
  	    printf("ProcessBlock(): Previous POS block not found.\n");
  	}
      }
  
      if (pcheckpoint && pblock->hashPrevBlock != hashBestChain && !Checkpoints::WantedByPendingSyncCheckpoint(hash))
      {
          // Extra checks to prevent "fill up memory by spamming with bogus blocks"
          int64 deltaTime = pblock->GetBlockTime() - pcheckpoint->nTime;
          CBigNum bnNewBlock;
          bnNewBlock.SetCompact(pblock->nBits);
          CBigNum bnRequired;
  
  		if (pblock->IsProofOfStake())
              bnRequired.SetCompact(ComputeMinStake(GetLastBlockIndex(pcheckpoint, true)->nBits, deltaTime, pblock->nTime));
          else
              bnRequired.SetCompact(ComputeMinWork(GetLastBlockIndex(pcheckpoint, false)->nBits, deltaTime));
  
          if (bnNewBlock > bnRequired)
          {
              if (pfrom)
                  pfrom->Misbehaving(100);
              return error("ProcessBlock() : block with too little %s", pblock->IsProofOfStake()? "proof-of-stake" : "proof-of-work");
          }
      }
  
      // ppcoin: ask for pending sync-checkpoint if any
      if (!IsInitialBlockDownload())
          Checkpoints::AskForPendingSyncCheckpoint(pfrom);
  
      // If don't already have its previous block, shunt it off to holding area until we get it
      if (!mapBlockIndex.count(pblock->hashPrevBlock))
      {
          printf("ProcessBlock: ORPHAN BLOCK, prev=%s\n", pblock->hashPrevBlock.ToString().substr(0,20).c_str());
          CBlock* pblock2 = new CBlock(*pblock);
          // ppcoin: check proof-of-stake
          if (pblock2->IsProofOfStake())
          {
              // Limited duplicity on stake: prevents block flood attack
              // Duplicate stake allowed only when there is orphan child block
              if (setStakeSeenOrphan.count(pblock2->GetProofOfStake()) && !mapOrphanBlocksByPrev.count(hash) && !Checkpoints::WantedByPendingSyncCheckpoint(hash))
                  return error("ProcessBlock() : duplicate proof-of-stake (%s, %d) for orphan block %s", pblock2->GetProofOfStake().first.ToString().c_str(), pblock2->GetProofOfStake().second, hash.ToString().c_str());
              else
                  setStakeSeenOrphan.insert(pblock2->GetProofOfStake());
          }
          mapOrphanBlocks.insert(make_pair(hash, pblock2));
          mapOrphanBlocksByPrev.insert(make_pair(pblock2->hashPrevBlock, pblock2));
  
          // Ask this guy to fill in what we're missing
          if (pfrom)
          {
              pfrom->PushGetBlocks(pindexBest, GetOrphanRoot(pblock2));
              // ppcoin: getblocks may not obtain the ancestor block rejected
              // earlier by duplicate-stake check so we ask for it again directly
              if (!IsInitialBlockDownload())
                  pfrom->AskFor(CInv(MSG_BLOCK, WantedByOrphan(pblock2)));
          }
          return true;
      }
  
      // Store to disk
      if (!pblock->AcceptBlock())
          return error("ProcessBlock() : AcceptBlock FAILED");
  
      // Recursively process any orphan blocks that depended on this one
      vector<uint256> vWorkQueue;
      vWorkQueue.push_back(hash);
      for (unsigned int i = 0; i < vWorkQueue.size(); i++)
      {
          uint256 hashPrev = vWorkQueue[i];
          for (multimap<uint256, CBlock*>::iterator mi = mapOrphanBlocksByPrev.lower_bound(hashPrev);
               mi != mapOrphanBlocksByPrev.upper_bound(hashPrev);
               ++mi)
          {
              CBlock* pblockOrphan = (*mi).second;
              if (pblockOrphan->AcceptBlock())
                  vWorkQueue.push_back(pblockOrphan->GetHash());
              mapOrphanBlocks.erase(pblockOrphan->GetHash());
              setStakeSeenOrphan.erase(pblockOrphan->GetProofOfStake());
              delete pblockOrphan;
          }
          mapOrphanBlocksByPrev.erase(hashPrev);
      }
  
      printf("ProcessBlock: ACCEPTED\n");
  
      // ppcoin: if responsible for sync-checkpoint send it
      if (pfrom && !CSyncCheckpoint::strMasterPrivKey.empty())
          Checkpoints::SendSyncCheckpoint(Checkpoints::AutoSelectSyncCheckpoint());
  
      return true;
  }
  
  // ppcoin: sign block
  bool CBlock::SignBlock(const CKeyStore& keystore)
  {
      vector<valtype> vSolutions;
      txnouttype whichType;
  
      if(!IsProofOfStake())
      {
          for(unsigned int i = 0; i < vtx[0].vout.size(); i++)
          {
              const CTxOut& txout = vtx[0].vout[i];
  
              if (!Solver(txout.scriptPubKey, whichType, vSolutions))
                  continue;
  
              if (whichType == TX_PUBKEY)
              {
                  // Sign
                  valtype& vchPubKey = vSolutions[0];
                  CKey key;
  
                  if (!keystore.GetKey(Hash160(vchPubKey), key))
                      continue;
                  if (key.GetPubKey() != vchPubKey)
                      continue;
                  if(!key.Sign(GetHash(), vchBlockSig))
                      continue;
  
                  return true;
              }
          }
      }
      else
      {
          const CTxOut& txout = vtx[1].vout[1];
  
          if (!Solver(txout.scriptPubKey, whichType, vSolutions))
              return false;
  
          if (whichType == TX_PUBKEY)
          {
              // Sign
              valtype& vchPubKey = vSolutions[0];
              CKey key;
  
              if (!keystore.GetKey(Hash160(vchPubKey), key))
                  return false;
              if (key.GetPubKey() != vchPubKey)
                  return false;
  
              return key.Sign(GetHash(), vchBlockSig);
          }
      }
  
      printf("Sign failed\n");
      return false;
  }
  
  // ppcoin: check block signature
  bool CBlock::CheckBlockSignature() const
  {
      if (GetHash() == (!fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet))
          return vchBlockSig.empty();
  
      vector<valtype> vSolutions;
      txnouttype whichType;
  
      if(IsProofOfStake())
      {
          const CTxOut& txout = vtx[1].vout[1];
  
          if (!Solver(txout.scriptPubKey, whichType, vSolutions))
              return false;
          if (whichType == TX_PUBKEY)
          {
              valtype& vchPubKey = vSolutions[0];
              CKey key;
              if (!key.SetPubKey(vchPubKey))
                  return false;
              if (vchBlockSig.empty())
                  return false;
              return key.Verify(GetHash(), vchBlockSig);
          }
      }
      else
      {
          for(unsigned int i = 0; i < vtx[0].vout.size(); i++)
          {
              const CTxOut& txout = vtx[0].vout[i];
  
              if (!Solver(txout.scriptPubKey, whichType, vSolutions))
                  return false;
  
              if (whichType == TX_PUBKEY)
              {
                  // Verify
                  valtype& vchPubKey = vSolutions[0];
                  CKey key;
                  if (!key.SetPubKey(vchPubKey))
                      continue;
                  if (vchBlockSig.empty())
                      continue;
                  if(!key.Verify(GetHash(), vchBlockSig))
                      continue;
  
                  return true;
              }
          }
      }
      return false;
  }
  
  
  bool CheckDiskSpace(uint64 nAdditionalBytes)
  {
      uint64 nFreeBytesAvailable = filesystem::space(GetDataDir()).available;
  
      // Check for nMinDiskSpace bytes (currently 50MB)
      if (nFreeBytesAvailable < nMinDiskSpace + nAdditionalBytes)
      {
          fShutdown = true;
          string strMessage = _("Warning: Disk space is low!");
          strMiscWarning = strMessage;
          printf("*** %s\n", strMessage.c_str());
          uiInterface.ThreadSafeMessageBox(strMessage, "OfferlibationCoin", CClientUIInterface::OK | CClientUIInterface::ICON_EXCLAMATION | CClientUIInterface::MODAL);
          StartShutdown();
          return false;
      }
      return true;
  }
  
  
  static filesystem::path BlockFilePath(unsigned int nFile)
  {
      string strBlockFn = strprintf("blk%04u.dat", nFile);
      return GetDataDir() / strBlockFn;
  }
  
  
  FILE* OpenBlockFile(unsigned int nFile, unsigned int nBlockPos, const char* pszMode)
  {
      if ((nFile < 1) || (nFile == (unsigned int) -1))
          return NULL;
      FILE* file = fopen(BlockFilePath(nFile).string().c_str(), pszMode);
      if (!file)
          return NULL;
      if (nBlockPos != 0 && !strchr(pszMode, 'a') && !strchr(pszMode, 'w'))
      {
          if (fseek(file, nBlockPos, SEEK_SET) != 0)
          {
              fclose(file);
              return NULL;
          }
      }
      return file;
  }
  
  
  static unsigned int nCurrentBlockFile = 1;
  
  FILE* AppendBlockFile(unsigned int& nFileRet)
  {
      nFileRet = 0;
      loop
      {
          FILE* file = OpenBlockFile(nCurrentBlockFile, 0, "ab");
          if (!file)
              return NULL;
          if (fseek(file, 0, SEEK_END) != 0)
              return NULL;
          // FAT32 file size max 4GB, fseek and ftell max 2GB, so we must stay under 2GB
          if (ftell(file) < (long)(0x7F000000 - MAX_SIZE))
          {
              nFileRet = nCurrentBlockFile;
              return file;
          }
          fclose(file);
          nCurrentBlockFile++;
      }
  }
  
  
  bool LoadBlockIndex(bool fAllowNew)
  {
      if (fTestNet)
      {
          pchMessageStart[0] = 0x14;
          pchMessageStart[1] = 0x10;
          pchMessageStart[2] = 0x03;
          pchMessageStart[3] = 0x1C;
  
          bnProofOfStakeLimit = bnProofOfStakeLimitTestNet; // 0x00000fff PoS base target is fixed in testnet
          bnProofOfWorkLimit = bnProofOfWorkLimitTestNet; // 0x0000ffff PoW base target is fixed in testnet
          nStakeMinAge = 15 * 60; // test net min age is 20 min
          nStakeMaxAge = 60 * 60; // test net min age is 60 min
  		nModifierInterval = 60; // test modifier interval is 2 minutes
          nCoinbaseMaturity = 10; // test maturity is 10 blocks
          nStakeTargetSpacing = 3 * 60; // test block spacing is 3 minutes
      }
  
      //
      // Load block index
      //
      CTxDB txdb("cr");
      if (!txdb.LoadBlockIndex())
          return false;
      txdb.Close();
  
      //
      // Init with genesis block
      //
      if (mapBlockIndex.empty())
      {
          if (!fAllowNew)
              return false;
  
          // Genesis block
          const char* pszTimestamp = "nothing to say.China's annual parliament meets under economic clouds. 2016-03-29";
          CTransaction txNew;
          txNew.nTime = nChainStartTime;
          txNew.nVersion=2;
          txNew.vin.resize(1);
          txNew.vout.resize(1);
          txNew.vin[0].scriptSig = CScript() << 486604799 << CBigNum(9999) << vector<unsigned char>((const unsigned char*)pszTimestamp, (const unsigned char*)pszTimestamp + strlen(pszTimestamp));
          txNew.vout[0].SetEmpty();
  
          CBlock block;
          block.vtx.push_back(txNew);
          block.hashPrevBlock = 0;
          block.hashMerkleRoot = block.BuildMerkleTree();
          block.nVersion = 1;
          block.nTime    = nChainStartTime + 1;
          block.nBits    = bnProofOfWorkLimit.GetCompact();
          block.nNonce   = 521147 ;
  
        if (true  && (block.GetHash() != hashGenesisBlock))
          {
  
          // This will figure out a valid hash and Nonce if you're
          // creating a different genesis block:
              uint256 hashTarget = CBigNum().SetCompact(block.nBits).getuint256();
              while (block.GetHash() > hashTarget)
                 {
                     ++block.nNonce;
                     if (block.nNonce == 0)
                     {
                         printf("NONCE WRAPPED, incrementing time");
                         ++block.nTime;
                     }
                     if ((block.nNonce & 0xFFF) == 0)
                     {
                         printf("nonce %08X: hash = %s (target = %s)\n", block.nNonce, block.GetHash().ToString().c_str(), hashTarget.ToString().c_str());
                     }
  
                 }
          }
  
  
          //// debug print block.print();
          printf("block.GetHash() == %s\n", block.GetHash().ToString().c_str());
          printf("block.hashMerkleRoot == %s\n", block.hashMerkleRoot.ToString().c_str());
          printf("block.nTime = %u \n", block.nTime);
          printf("block.nNonce = %u \n", block.nNonce);
  
          assert(block.hashMerkleRoot == uint256("0x0336366864b6352bef87f72041db972f88a1ed7a898e84674a4a9aee8ede039e"));
  		assert(block.GetHash() == (!fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet));
  
          // Start new block file
          unsigned int nFile;
          unsigned int nBlockPos;
          if (!block.WriteToDisk(nFile, nBlockPos))
              return error("LoadBlockIndex() : writing genesis block to disk failed");
          if (!block.AddToBlockIndex(nFile, nBlockPos))
              return error("LoadBlockIndex() : genesis block not accepted");
  
          // ppcoin: initialize synchronized checkpoint
          if (!Checkpoints::WriteSyncCheckpoint((!fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet)))
              return error("LoadBlockIndex() : failed to init sync checkpoint");
      }
  
      // ppcoin: if checkpoint master key changed must reset sync-checkpoint
      {
          CTxDB txdb;
          string strPubKey = "";
          if (!txdb.ReadCheckpointPubKey(strPubKey) || strPubKey != CSyncCheckpoint::strMasterPubKey)
          {
              // write checkpoint master key to db
              txdb.TxnBegin();
              if (!txdb.WriteCheckpointPubKey(CSyncCheckpoint::strMasterPubKey))
                  return error("LoadBlockIndex() : failed to write new checkpoint master key to db");
              if (!txdb.TxnCommit())
                  return error("LoadBlockIndex() : failed to commit new checkpoint master key to db");
              if ((!fTestNet) && !Checkpoints::ResetSyncCheckpoint())
                  return error("LoadBlockIndex() : failed to reset sync-checkpoint");
          }
          txdb.Close();
      }
  
      return true;
  }
  
  
  
  void PrintBlockTree()
  {
      // pre-compute tree structure
      map<CBlockIndex*, vector<CBlockIndex*> > mapNext;
      for (map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.begin(); mi != mapBlockIndex.end(); ++mi)
      {
          CBlockIndex* pindex = (*mi).second;
          mapNext[pindex->pprev].push_back(pindex);
          // test
          //while (rand() % 3 == 0)
          //    mapNext[pindex->pprev].push_back(pindex);
      }
  
      vector<pair<int, CBlockIndex*> > vStack;
      vStack.push_back(make_pair(0, pindexGenesisBlock));
  
      int nPrevCol = 0;
      while (!vStack.empty())
      {
          int nCol = vStack.back().first;
          CBlockIndex* pindex = vStack.back().second;
          vStack.pop_back();
  
          // print split or gap
          if (nCol > nPrevCol)
          {
              for (int i = 0; i < nCol-1; i++)
                  printf("| ");
              printf("|\\\n");
          }
          else if (nCol < nPrevCol)
          {
              for (int i = 0; i < nCol; i++)
                  printf("| ");
              printf("|\n");
         }
          nPrevCol = nCol;
  
          // print columns
          for (int i = 0; i < nCol; i++)
              printf("| ");
  
          // print item
          CBlock block;
          block.ReadFromDisk(pindex);
          printf("%d (%u,%u) %s  %08x  %s  mint %7s  tx %"PRIszu"",
              pindex->nHeight,
              pindex->nFile,
              pindex->nBlockPos,
              block.GetHash().ToString().c_str(),
              block.nBits,
              DateTimeStrFormat("%x %H:%M:%S", block.GetBlockTime()).c_str(),
              FormatMoney(pindex->nMint).c_str(),
              block.vtx.size());
  
          PrintWallets(block);
  
          // put the main time-chain first
          vector<CBlockIndex*>& vNext = mapNext[pindex];
          for (unsigned int i = 0; i < vNext.size(); i++)
          {
              if (vNext[i]->pnext)
              {
                  swap(vNext[0], vNext[i]);
                  break;
              }
          }
  
          // iterate children
          for (unsigned int i = 0; i < vNext.size(); i++)
              vStack.push_back(make_pair(nCol+i, vNext[i]));
      }
  }
  
  bool LoadExternalBlockFile(FILE* fileIn)
  {
      int64 nStart = GetTimeMillis();
  
      int nLoaded = 0;
      {
          LOCK(cs_main);
          try {
              CAutoFile blkdat(fileIn, SER_DISK, CLIENT_VERSION);
              unsigned int nPos = 0;
              while (nPos != (unsigned int)-1 && blkdat.good() && !fRequestShutdown)
              {
                  unsigned char pchData[65536];
                  do {
                      fseek(blkdat, nPos, SEEK_SET);
                      int nRead = fread(pchData, 1, sizeof(pchData), blkdat);
                      if (nRead <= 8)
                      {
                          nPos = (unsigned int)-1;
                          break;
                      }
                      void* nFind = memchr(pchData, pchMessageStart[0], nRead+1-sizeof(pchMessageStart));
                      if (nFind)
                      {
                          if (memcmp(nFind, pchMessageStart, sizeof(pchMessageStart))==0)
                          {
                              nPos += ((unsigned char*)nFind - pchData) + sizeof(pchMessageStart);
                              break;
                          }
                          nPos += ((unsigned char*)nFind - pchData) + 1;
                      }
                      else
                          nPos += sizeof(pchData) - sizeof(pchMessageStart) + 1;
                  } while(!fRequestShutdown);
                  if (nPos == (unsigned int)-1)
                      break;
                  fseek(blkdat, nPos, SEEK_SET);
                  unsigned int nSize;
                  blkdat >> nSize;
                  if (nSize > 0 && nSize <= MAX_BLOCK_SIZE)
                  {
                      CBlock block;
                      blkdat >> block;
                      if (ProcessBlock(NULL,&block))
                      {
                          nLoaded++;
                          nPos += 4 + nSize;
                      }
                  }
              }
          }
          catch (std::exception &e) {
              printf("%s() : Deserialize or I/O error caught during load\n",
                     __PRETTY_FUNCTION__);
          }
      }
      printf("Loaded %i blocks from external file in %"PRI64d"ms\n", nLoaded, GetTimeMillis() - nStart);
      return nLoaded > 0;
  }
  
  
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // CAlert
  //
  
  extern map<uint256, CAlert> mapAlerts;
  extern CCriticalSection cs_mapAlerts;
  
  string GetWarnings(string strFor)
  {
      int nPriority = 0;
      string strStatusBar;
      string strRPC;
  
      if (GetBoolArg("-testsafemode"))
          strRPC = "test";
  
      // Misc warnings like out of disk space and clock is wrong
      if (strMiscWarning != "")
      {
          nPriority = 1000;
          strStatusBar = strMiscWarning;
      }
  
      // ppcoin: should not enter safe mode for longer invalid chain
      // ppcoin: if sync-checkpoint is too old do not enter safe mode
      if (Checkpoints::IsSyncCheckpointTooOld(60 * 60 * 24 * 365) && !fTestNet && !IsInitialBlockDownload())
      {
          nPriority = 100;
          strStatusBar = "WARNING: Checkpoint is too old. Wait for block chain to download, or notify developers.";
      }
  
      // ppcoin: if detected invalid checkpoint enter safe mode
      if (Checkpoints::hashInvalidCheckpoint != 0)
      {
          nPriority = 3000;
          strStatusBar = strRPC = "WARNING: Invalid checkpoint found! Displayed transactions may not be correct! You may need to upgrade, or notify developers.";
      }
  
      // Alerts
      {
          LOCK(cs_mapAlerts);
          BOOST_FOREACH(PAIRTYPE(const uint256, CAlert)& item, mapAlerts)
          {
              const CAlert& alert = item.second;
              if (alert.AppliesToMe() && alert.nPriority > nPriority)
              {
                  nPriority = alert.nPriority;
                  strStatusBar = alert.strStatusBar;
                  if (nPriority > 1000)
                      strRPC = strStatusBar;  // ppcoin: safe mode for high alert
              }
          }
      }
  
      if (strFor == "statusbar")
          return strStatusBar;
      else if (strFor == "rpc")
          return strRPC;
      assert(!"GetWarnings() : invalid parameter");
      return "error";
  }
  
  
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // Messages
  //
  
  
  bool static AlreadyHave(CTxDB& txdb, const CInv& inv)
  {
      switch (inv.type)
      {
      case MSG_TX:
          {
          bool txInMap = false;
              {
              LOCK(mempool.cs);
              txInMap = (mempool.exists(inv.hash));
              }
          return txInMap ||
                 mapOrphanTransactions.count(inv.hash) ||
                 txdb.ContainsTx(inv.hash);
          }
  
      case MSG_BLOCK:
          return mapBlockIndex.count(inv.hash) ||
                 mapOrphanBlocks.count(inv.hash);
      }
      // Don't know what it is, just say we already got one
      return true;
  }
  
  
  
  
  // The message start string is designed to be unlikely to occur in normal data.
  // The characters are rarely used upper ASCII, not valid as UTF-8, and produce
  // a large 4-byte int at any alignment.
  unsigned char pchMessageStart[4] = { 0x14, 0x10, 0x03, 0x1D };
  
  bool static ProcessMessage(CNode* pfrom, string strCommand, CDataStream& vRecv)
  {
      static map<CService, CPubKey> mapReuseKey;
      RandAddSeedPerfmon();
      if (fDebug)
          printf("received: %s (%"PRIszu" bytes)\n", strCommand.c_str(), vRecv.size());
      if (mapArgs.count("-dropmessagestest") && GetRand(atoi(mapArgs["-dropmessagestest"])) == 0)
      {
          printf("dropmessagestest DROPPING RECV MESSAGE\n");
          return true;
      }
  
  
  
  
  
      if (strCommand == "version")
      {
          // Each connection can only send one version message
          if (pfrom->nVersion != 0)
          {
              pfrom->Misbehaving(1);
              return false;
          }
  
          int64 nTime;
          CAddress addrMe;
          CAddress addrFrom;
          uint64 nNonce = 1;
          vRecv >> pfrom->nVersion >> pfrom->nServices >> nTime >> addrMe;
          if (pfrom->nVersion < MIN_PROTO_VERSION)
          {
              // Since February 20, 2012, the protocol is initiated at version 209,
              // and earlier versions are no longer supported
              printf("partner %s using obsolete version %i; disconnecting\n", pfrom->addr.ToString().c_str(), pfrom->nVersion);
              pfrom->fDisconnect = true;
              return false;
          }
  
          if (pfrom->nVersion == 10300)
              pfrom->nVersion = 300;
          if (!vRecv.empty())
              vRecv >> addrFrom >> nNonce;
          if (!vRecv.empty())
              vRecv >> pfrom->strSubVer;
          if (!vRecv.empty())
              vRecv >> pfrom->nStartingHeight;
  
          if (pfrom->fInbound && addrMe.IsRoutable())
          {
              pfrom->addrLocal = addrMe;
              SeenLocal(addrMe);
          }
  
          // Disconnect if we connected to ourself
          if (nNonce == nLocalHostNonce && nNonce > 1)
          {
              printf("connected to self at %s, disconnecting\n", pfrom->addr.ToString().c_str());
              pfrom->fDisconnect = true;
              return true;
          }
  
          // ppcoin: record my external IP reported by peer
          if (addrFrom.IsRoutable() && addrMe.IsRoutable())
              addrSeenByPeer = addrMe;
  
          // Be shy and don't send version until we hear
          if (pfrom->fInbound)
              pfrom->PushVersion();
  
          pfrom->fClient = !(pfrom->nServices & NODE_NETWORK);
  
          AddTimeData(pfrom->addr, nTime);
  
          // Change version
          pfrom->PushMessage("verack");
          pfrom->vSend.SetVersion(min(pfrom->nVersion, PROTOCOL_VERSION));
  
          if (!pfrom->fInbound)
          {
              // Advertise our address
              if (!fNoListen && !IsInitialBlockDownload())
              {
                  CAddress addr = GetLocalAddress(&pfrom->addr);
                  if (addr.IsRoutable())
                      pfrom->PushAddress(addr);
              }
  
              // Get recent addresses
              if (pfrom->fOneShot || pfrom->nVersion >= CADDR_TIME_VERSION || addrman.size() < 1000)
              {
                  pfrom->PushMessage("getaddr");
                  pfrom->fGetAddr = true;
              }
              addrman.Good(pfrom->addr);
          } else {
              if (((CNetAddr)pfrom->addr) == (CNetAddr)addrFrom)
              {
                  addrman.Add(addrFrom, addrFrom);
                  addrman.Good(addrFrom);
              }
          }
  
          // Ask the first connected node for block updates
          static int nAskedForBlocks = 0;
          if (!pfrom->fClient && !pfrom->fOneShot &&
              (pfrom->nStartingHeight > (nBestHeight - 144)) &&
              (pfrom->nVersion < NOBLKS_VERSION_START ||
               pfrom->nVersion >= NOBLKS_VERSION_END) &&
               (nAskedForBlocks < 1 || vNodes.size() <= 1))
          {
              nAskedForBlocks++;
              pfrom->PushGetBlocks(pindexBest, uint256(0));
          }
  
          // Relay alerts
          {
              LOCK(cs_mapAlerts);
              BOOST_FOREACH(PAIRTYPE(const uint256, CAlert)& item, mapAlerts)
                  item.second.RelayTo(pfrom);
          }
  
          // ppcoin: relay sync-checkpoint
          {
              LOCK(Checkpoints::cs_hashSyncCheckpoint);
              if (!Checkpoints::checkpointMessage.IsNull())
                  Checkpoints::checkpointMessage.RelayTo(pfrom);
          }
  
          pfrom->fSuccessfullyConnected = true;
  
          printf("receive version message: version %d, blocks=%d, us=%s, them=%s, peer=%s\n", pfrom->nVersion, pfrom->nStartingHeight, addrMe.ToString().c_str(), addrFrom.ToString().c_str(), pfrom->addr.ToString().c_str());
  
          cPeerBlockCounts.input(pfrom->nStartingHeight);
  
          // ppcoin: ask for pending sync-checkpoint if any
          if (!IsInitialBlockDownload())
              Checkpoints::AskForPendingSyncCheckpoint(pfrom);
      }
  
  
      else if (pfrom->nVersion == 0)
      {
          // Must have a version message before anything else
          pfrom->Misbehaving(1);
          return false;
      }
  
  
      else if (strCommand == "verack")
      {
          pfrom->vRecv.SetVersion(min(pfrom->nVersion, PROTOCOL_VERSION));
      }
  
  
      else if (strCommand == "addr")
      {
          vector<CAddress> vAddr;
          vRecv >> vAddr;
  
          // Don't want addr from older versions unless seeding
          if (pfrom->nVersion < CADDR_TIME_VERSION && addrman.size() > 1000)
              return true;
          if (vAddr.size() > 1000)
          {
              pfrom->Misbehaving(20);
              return error("message addr size() = %"PRIszu"", vAddr.size());
          }
  
          // Store the new addresses
          vector<CAddress> vAddrOk;
          int64 nNow = GetAdjustedTime();
          int64 nSince = nNow - 10 * 60;
          BOOST_FOREACH(CAddress& addr, vAddr)
          {
              if (fShutdown)
                  return true;
              if (addr.nTime <= 100000000 || addr.nTime > nNow + 10 * 60)
                  addr.nTime = nNow - 5 * 24 * 60 * 60;
              pfrom->AddAddressKnown(addr);
              bool fReachable = IsReachable(addr);
              if (addr.nTime > nSince && !pfrom->fGetAddr && vAddr.size() <= 10 && addr.IsRoutable())
              {
                  // Relay to a limited number of other nodes
                  {
                      LOCK(cs_vNodes);
                      // Use deterministic randomness to send to the same nodes for 24 hours
                      // at a time so the setAddrKnowns of the chosen nodes prevent repeats
                      static uint256 hashSalt;
                      if (hashSalt == 0)
                          hashSalt = GetRandHash();
                      uint64 hashAddr = addr.GetHash();
                      uint256 hashRand = hashSalt ^ (hashAddr<<32) ^ ((GetTime()+hashAddr)/(24*60*60));
                      hashRand = Hash(BEGIN(hashRand), END(hashRand));
                      multimap<uint256, CNode*> mapMix;
                      BOOST_FOREACH(CNode* pnode, vNodes)
                      {
                          if (pnode->nVersion < CADDR_TIME_VERSION)
                              continue;
                          unsigned int nPointer;
                          memcpy(&nPointer, &pnode, sizeof(nPointer));
                          uint256 hashKey = hashRand ^ nPointer;
                          hashKey = Hash(BEGIN(hashKey), END(hashKey));
                          mapMix.insert(make_pair(hashKey, pnode));
                      }
                      int nRelayNodes = fReachable ? 2 : 1; // limited relaying of addresses outside our network(s)
                      for (multimap<uint256, CNode*>::iterator mi = mapMix.begin(); mi != mapMix.end() && nRelayNodes-- > 0; ++mi)
                          ((*mi).second)->PushAddress(addr);
                  }
              }
              // Do not store addresses outside our network
              if (fReachable)
                  vAddrOk.push_back(addr);
          }
          addrman.Add(vAddrOk, pfrom->addr, 2 * 60 * 60);
          if (vAddr.size() < 1000)
              pfrom->fGetAddr = false;
          if (pfrom->fOneShot)
              pfrom->fDisconnect = true;
      }
  
  
      else if (strCommand == "inv")
      {
          vector<CInv> vInv;
          vRecv >> vInv;
          if (vInv.size() > MAX_INV_SZ)
          {
              pfrom->Misbehaving(20);
              return error("message inv size() = %"PRIszu"", vInv.size());
          }
  
          // find last block in inv vector
          unsigned int nLastBlock = (unsigned int)(-1);
          for (unsigned int nInv = 0; nInv < vInv.size(); nInv++) {
              if (vInv[vInv.size() - 1 - nInv].type == MSG_BLOCK) {
                  nLastBlock = vInv.size() - 1 - nInv;
                  break;
              }
          }
          CTxDB txdb("r");
          for (unsigned int nInv = 0; nInv < vInv.size(); nInv++)
          {
              const CInv &inv = vInv[nInv];
  
              if (fShutdown)
                  return true;
              pfrom->AddInventoryKnown(inv);
  
              bool fAlreadyHave = AlreadyHave(txdb, inv);
              if (fDebug)
                  printf("  got inventory: %s  %s\n", inv.ToString().c_str(), fAlreadyHave ? "have" : "new");
  
              if (!fAlreadyHave)
                  pfrom->AskFor(inv);
              else if (inv.type == MSG_BLOCK && mapOrphanBlocks.count(inv.hash)) {
                  pfrom->PushGetBlocks(pindexBest, GetOrphanRoot(mapOrphanBlocks[inv.hash]));
              } else if (nInv == nLastBlock) {
                  // In case we are on a very long side-chain, it is possible that we already have
                  // the last block in an inv bundle sent in response to getblocks. Try to detect
                  // this situation and push another getblocks to continue.
                  pfrom->PushGetBlocks(mapBlockIndex[inv.hash], uint256(0));
                  if (fDebug)
                      printf("force request: %s\n", inv.ToString().c_str());
              }
  
              // Track requests for our stuff
              Inventory(inv.hash);
          }
      }
  
  
      else if (strCommand == "getdata")
      {
          vector<CInv> vInv;
          vRecv >> vInv;
          if (vInv.size() > MAX_INV_SZ)
          {
              pfrom->Misbehaving(20);
              return error("message getdata size() = %"PRIszu"", vInv.size());
          }
  
          if (fDebugNet || (vInv.size() != 1))
              printf("received getdata (%"PRIszu" invsz)\n", vInv.size());
  
          BOOST_FOREACH(const CInv& inv, vInv)
          {
              if (fShutdown)
                  return true;
              if (fDebugNet || (vInv.size() == 1))
                  printf("received getdata for: %s\n", inv.ToString().c_str());
  
              if (inv.type == MSG_BLOCK)
              {
                  // Send block from disk
                  map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(inv.hash);
                  if (mi != mapBlockIndex.end())
                  {
                      CBlock block;
                      block.ReadFromDisk((*mi).second);
                      pfrom->PushMessage("block", block);
  
                      // Trigger them to send a getblocks request for the next batch of inventory
                      if (inv.hash == pfrom->hashContinue)
                      {
                          // ppcoin: send latest proof-of-work block to allow the
                          // download node to accept as orphan (proof-of-stake 
                          // block might be rejected by stake connection check)
                          vector<CInv> vInv;
                          vInv.push_back(CInv(MSG_BLOCK, GetLastBlockIndex(pindexBest, false)->GetBlockHash()));
                          pfrom->PushMessage("inv", vInv);
                          pfrom->hashContinue = 0;
                      }
                  }
              }
              else if (inv.IsKnownType())
              {
                  // Send stream from relay memory
                  bool pushed = false;
                  {
                      LOCK(cs_mapRelay);
                      map<CInv, CDataStream>::iterator mi = mapRelay.find(inv);
                      if (mi != mapRelay.end()) {
                          pfrom->PushMessage(inv.GetCommand(), (*mi).second);
                          pushed = true;
                      }
                  }
                  if (!pushed && inv.type == MSG_TX) {
                      LOCK(mempool.cs);
                      if (mempool.exists(inv.hash)) {
                          CTransaction tx = mempool.lookup(inv.hash);
                          CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
                          ss.reserve(1000);
                          ss << tx;
                          pfrom->PushMessage("tx", ss);
                      }
                  }
              }
  
              // Track requests for our stuff
              Inventory(inv.hash);
          }
      }
  
  
      else if (strCommand == "getblocks")
      {
          CBlockLocator locator;
          uint256 hashStop;
          vRecv >> locator >> hashStop;
  
          // Find the last block the caller has in the main chain
          CBlockIndex* pindex = locator.GetBlockIndex();
  
          // Send the rest of the chain
          if (pindex)
              pindex = pindex->pnext;
          int nLimit = 500;
          printf("getblocks %d to %s limit %d\n", (pindex ? pindex->nHeight : -1), hashStop.ToString().substr(0,20).c_str(), nLimit);
          for (; pindex; pindex = pindex->pnext)
          {
              if (pindex->GetBlockHash() == hashStop)
              {
                  printf("  getblocks stopping at %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString().substr(0,20).c_str());
                  // ppcoin: tell downloading node about the latest block if it's
                  // without risk being rejected due to stake connection check
                  if (hashStop != hashBestChain && pindex->GetBlockTime() + nStakeMinAge > pindexBest->GetBlockTime())
                      pfrom->PushInventory(CInv(MSG_BLOCK, hashBestChain));
                  break;
              }
              pfrom->PushInventory(CInv(MSG_BLOCK, pindex->GetBlockHash()));
              if (--nLimit <= 0)
              {
                  // When this block is requested, we'll send an inv that'll make them
                  // getblocks the next batch of inventory.
                  printf("  getblocks stopping at limit %d %s\n", pindex->nHeight, pindex->GetBlockHash().ToString().substr(0,20).c_str());
                  pfrom->hashContinue = pindex->GetBlockHash();
                  break;
              }
          }
      }
      else if (strCommand == "checkpoint")
      {
          CSyncCheckpoint checkpoint;
          vRecv >> checkpoint;
  
          if (checkpoint.ProcessSyncCheckpoint(pfrom))
          {
              // Relay
              pfrom->hashCheckpointKnown = checkpoint.hashCheckpoint;
              LOCK(cs_vNodes);
              BOOST_FOREACH(CNode* pnode, vNodes)
                  checkpoint.RelayTo(pnode);
          }
      }
  
      else if (strCommand == "getheaders")
      {
          CBlockLocator locator;
          uint256 hashStop;
          vRecv >> locator >> hashStop;
  
          CBlockIndex* pindex = NULL;
          if (locator.IsNull())
          {
              // If locator is null, return the hashStop block
              map<uint256, CBlockIndex*>::iterator mi = mapBlockIndex.find(hashStop);
              if (mi == mapBlockIndex.end())
                  return true;
              pindex = (*mi).second;
          }
          else
          {
              // Find the last block the caller has in the main chain
              pindex = locator.GetBlockIndex();
              if (pindex)
                  pindex = pindex->pnext;
          }
  
          vector<CBlock> vHeaders;
          int nLimit = 2000;
          printf("getheaders %d to %s\n", (pindex ? pindex->nHeight : -1), hashStop.ToString().substr(0,20).c_str());
          for (; pindex; pindex = pindex->pnext)
          {
              vHeaders.push_back(pindex->GetBlockHeader());
              if (--nLimit <= 0 || pindex->GetBlockHash() == hashStop)
                  break;
          }
          pfrom->PushMessage("headers", vHeaders);
      }
  
  
      else if (strCommand == "tx")
      {
          vector<uint256> vWorkQueue;
          vector<uint256> vEraseQueue;
          CDataStream vMsg(vRecv);
          CTxDB txdb("r");
          CTransaction tx;
          vRecv >> tx;
  
          CInv inv(MSG_TX, tx.GetHash());
          pfrom->AddInventoryKnown(inv);
  
          bool fMissingInputs = false;
          if (tx.AcceptToMemoryPool(txdb, true, &fMissingInputs))
          {
              SyncWithWallets(tx, NULL, true);
              RelayMessage(inv, vMsg);
              mapAlreadyAskedFor.erase(inv);
              vWorkQueue.push_back(inv.hash);
              vEraseQueue.push_back(inv.hash);
  
              // Recursively process any orphan transactions that depended on this one
              for (unsigned int i = 0; i < vWorkQueue.size(); i++)
              {
                  uint256 hashPrev = vWorkQueue[i];
                  for (map<uint256, CDataStream*>::iterator mi = mapOrphanTransactionsByPrev[hashPrev].begin();
                       mi != mapOrphanTransactionsByPrev[hashPrev].end();
                       ++mi)
                  {
                      const CDataStream& vMsg = *((*mi).second);
                      CTransaction tx;
                      CDataStream(vMsg) >> tx;
                      CInv inv(MSG_TX, tx.GetHash());
                      bool fMissingInputs2 = false;
  
                      if (tx.AcceptToMemoryPool(txdb, true, &fMissingInputs2))
                      {
                          printf("   accepted orphan tx %s\n", inv.hash.ToString().substr(0,10).c_str());
                          SyncWithWallets(tx, NULL, true);
                          RelayMessage(inv, vMsg);
                          mapAlreadyAskedFor.erase(inv);
                          vWorkQueue.push_back(inv.hash);
                          vEraseQueue.push_back(inv.hash);
                      }
                      else if (!fMissingInputs2)
                      {
                          // invalid orphan
                          vEraseQueue.push_back(inv.hash);
                          printf("   removed invalid orphan tx %s\n", inv.hash.ToString().substr(0,10).c_str());
                      }
                  }
              }
  
              BOOST_FOREACH(uint256 hash, vEraseQueue)
                  EraseOrphanTx(hash);
          }
          else if (fMissingInputs)
          {
              AddOrphanTx(vMsg);
  
              // DoS prevention: do not allow mapOrphanTransactions to grow unbounded
              unsigned int nEvicted = LimitOrphanTxSize(MAX_ORPHAN_TRANSACTIONS);
              if (nEvicted > 0)
                  printf("mapOrphan overflow, removed %u tx\n", nEvicted);
          }
          if (tx.nDoS) pfrom->Misbehaving(tx.nDoS);
      }
  
  
      else if (strCommand == "block")
      {
          CBlock block;
          vRecv >> block;
  
          printf("received block %s\n", block.GetHash().ToString().substr(0,20).c_str());
          // block.print();
  
          CInv inv(MSG_BLOCK, block.GetHash());
          pfrom->AddInventoryKnown(inv);
  
          if (ProcessBlock(pfrom, &block))
              mapAlreadyAskedFor.erase(inv);
          if (block.nDoS) pfrom->Misbehaving(block.nDoS);
      }
  
  
      else if (strCommand == "getaddr")
      {
          pfrom->vAddrToSend.clear();
          vector<CAddress> vAddr = addrman.GetAddr();
          BOOST_FOREACH(const CAddress &addr, vAddr)
              pfrom->PushAddress(addr);
      }
  
  
      else if (strCommand == "mempool")
      {
          std::vector<uint256> vtxid;
          mempool.queryHashes(vtxid);
          vector<CInv> vInv;
          for (unsigned int i = 0; i < vtxid.size(); i++) {
              CInv inv(MSG_TX, vtxid[i]);
              vInv.push_back(inv);
              if (i == (MAX_INV_SZ - 1))
                      break;
          }
          if (vInv.size() > 0)
              pfrom->PushMessage("inv", vInv);
      }
  
  
      else if (strCommand == "checkorder")
      {
          uint256 hashReply;
          vRecv >> hashReply;
  
          if (!GetBoolArg("-allowreceivebyip"))
          {
              pfrom->PushMessage("reply", hashReply, (int)2, string(""));
              return true;
          }
  
          CWalletTx order;
          vRecv >> order;
  
          /// we have a chance to check the order here
  
          // Keep giving the same key to the same ip until they use it
          if (!mapReuseKey.count(pfrom->addr))
              pwalletMain->GetKeyFromPool(mapReuseKey[pfrom->addr], true);
  
          // Send back approval of order and pubkey to use
          CScript scriptPubKey;
          scriptPubKey << mapReuseKey[pfrom->addr] << OP_CHECKSIG;
          pfrom->PushMessage("reply", hashReply, (int)0, scriptPubKey);
      }
  
  
      else if (strCommand == "reply")
      {
          uint256 hashReply;
          vRecv >> hashReply;
  
          CRequestTracker tracker;
          {
              LOCK(pfrom->cs_mapRequests);
              map<uint256, CRequestTracker>::iterator mi = pfrom->mapRequests.find(hashReply);
              if (mi != pfrom->mapRequests.end())
              {
                  tracker = (*mi).second;
                  pfrom->mapRequests.erase(mi);
              }
          }
          if (!tracker.IsNull())
              tracker.fn(tracker.param1, vRecv);
      }
  
  
      else if (strCommand == "ping")
      {
          if (pfrom->nVersion > BIP0031_VERSION)
          {
              uint64 nonce = 0;
              vRecv >> nonce;
              // Echo the message back with the nonce. This allows for two useful features:
              //
              // 1) A remote node can quickly check if the connection is operational
              // 2) Remote nodes can measure the latency of the network thread. If this node
              //    is overloaded it won't respond to pings quickly and the remote node can
              //    avoid sending us more work, like chain download requests.
              //
              // The nonce stops the remote getting confused between different pings: without
              // it, if the remote node sends a ping once per second and this node takes 5
              // seconds to respond to each, the 5th ping the remote sends would appear to
              // return very quickly.
              pfrom->PushMessage("pong", nonce);
          }
      }
  
  
      else if (strCommand == "alert")
      {
          CAlert alert;
          vRecv >> alert;
  
          uint256 alertHash = alert.GetHash();
          if (pfrom->setKnown.count(alertHash) == 0)
          {
              if (alert.ProcessAlert())
              {
                  // Relay
                  pfrom->setKnown.insert(alertHash);
                  {
                      LOCK(cs_vNodes);
                      BOOST_FOREACH(CNode* pnode, vNodes)
                          alert.RelayTo(pnode);
                  }
              }
              else {
                  // Small DoS penalty so peers that send us lots of
                  // duplicate/expired/invalid-signature/whatever alerts
                  // eventually get banned.
                  // This isn't a Misbehaving(100) (immediate ban) because the
                  // peer might be an older or different implementation with
                  // a different signature key, etc.
                  pfrom->Misbehaving(10);
              }
          }
      }
  
  
      else
      {
          // Ignore unknown commands for extensibility
      }
  
  
      // Update the last seen time for this node's address
      if (pfrom->fNetworkNode)
          if (strCommand == "version" || strCommand == "addr" || strCommand == "inv" || strCommand == "getdata" || strCommand == "ping")
              AddressCurrentlyConnected(pfrom->addr);
  
  
      return true;
  }
  
  bool ProcessMessages(CNode* pfrom)
  {
      CDataStream& vRecv = pfrom->vRecv;
      if (vRecv.empty())
          return true;
      //if (fDebug)
      //    printf("ProcessMessages(%u bytes)\n", vRecv.size());
  
      //
      // Message format
      //  (4) message start
      //  (12) command
      //  (4) size
      //  (4) checksum
      //  (x) data
      //
  
      loop
      {
          // Don't bother if send buffer is too full to respond anyway
          if (pfrom->vSend.size() >= SendBufferSize())
              break;
  
          // Scan for message start
          CDataStream::iterator pstart = search(vRecv.begin(), vRecv.end(), BEGIN(pchMessageStart), END(pchMessageStart));
          int nHeaderSize = vRecv.GetSerializeSize(CMessageHeader());
          if (vRecv.end() - pstart < nHeaderSize)
          {
              if ((int)vRecv.size() > nHeaderSize)
              {
                  printf("\n\nPROCESSMESSAGE MESSAGESTART NOT FOUND\n\n");
                  vRecv.erase(vRecv.begin(), vRecv.end() - nHeaderSize);
              }
              break;
          }
          if (pstart - vRecv.begin() > 0)
              printf("\n\nPROCESSMESSAGE SKIPPED %"PRIpdd" BYTES\n\n", pstart - vRecv.begin());
          vRecv.erase(vRecv.begin(), pstart);
  
          // Read header
          vector<char> vHeaderSave(vRecv.begin(), vRecv.begin() + nHeaderSize);
          CMessageHeader hdr;
          vRecv >> hdr;
          if (!hdr.IsValid())
          {
              printf("\n\nPROCESSMESSAGE: ERRORS IN HEADER %s\n\n\n", hdr.GetCommand().c_str());
              continue;
          }
          string strCommand = hdr.GetCommand();
  
          // Message size
          unsigned int nMessageSize = hdr.nMessageSize;
          if (nMessageSize > MAX_SIZE)
          {
              printf("ProcessMessages(%s, %u bytes) : nMessageSize > MAX_SIZE\n", strCommand.c_str(), nMessageSize);
              continue;
          }
          if (nMessageSize > vRecv.size())
          {
              // Rewind and wait for rest of message
              vRecv.insert(vRecv.begin(), vHeaderSave.begin(), vHeaderSave.end());
              break;
          }
  
          // Checksum
          uint256 hash = Hash(vRecv.begin(), vRecv.begin() + nMessageSize);
          unsigned int nChecksum = 0;
          memcpy(&nChecksum, &hash, sizeof(nChecksum));
          if (nChecksum != hdr.nChecksum)
          {
              printf("ProcessMessages(%s, %u bytes) : CHECKSUM ERROR nChecksum=%08x hdr.nChecksum=%08x\n",
                 strCommand.c_str(), nMessageSize, nChecksum, hdr.nChecksum);
              continue;
          }
  
          // Copy message to its own buffer
          CDataStream vMsg(vRecv.begin(), vRecv.begin() + nMessageSize, vRecv.nType, vRecv.nVersion);
          vRecv.ignore(nMessageSize);
  
          // Process message
          bool fRet = false;
          try
          {
              {
                  LOCK(cs_main);
                  fRet = ProcessMessage(pfrom, strCommand, vMsg);
              }
              if (fShutdown)
                  return true;
          }
          catch (std::ios_base::failure& e)
          {
              if (strstr(e.what(), "end of data"))
              {
                  // Allow exceptions from under-length message on vRecv
                  printf("ProcessMessages(%s, %u bytes) : Exception '%s' caught, normally caused by a message being shorter than its stated length\n", strCommand.c_str(), nMessageSize, e.what());
              }
              else if (strstr(e.what(), "size too large"))
              {
                  // Allow exceptions from over-long size
                  printf("ProcessMessages(%s, %u bytes) : Exception '%s' caught\n", strCommand.c_str(), nMessageSize, e.what());
              }
              else
              {
                  PrintExceptionContinue(&e, "ProcessMessages()");
              }
          }
          catch (std::exception& e) {
              PrintExceptionContinue(&e, "ProcessMessages()");
          } catch (...) {
              PrintExceptionContinue(NULL, "ProcessMessages()");
          }
  
          if (!fRet)
              printf("ProcessMessage(%s, %u bytes) FAILED\n", strCommand.c_str(), nMessageSize);
      }
  
      vRecv.Compact();
      return true;
  }
  
  
  bool SendMessages(CNode* pto, bool fSendTrickle)
  {
      TRY_LOCK(cs_main, lockMain);
      if (lockMain) {
          // Don't send anything until we get their version message
          if (pto->nVersion == 0)
              return true;
  
          // Keep-alive ping. We send a nonce of zero because we don't use it anywhere
          // right now.
          if (pto->nLastSend && GetTime() - pto->nLastSend > 30 * 60 && pto->vSend.empty()) {
              uint64 nonce = 0;
              if (pto->nVersion > BIP0031_VERSION)
                  pto->PushMessage("ping", nonce);
              else
                  pto->PushMessage("ping");
          }
  
          // Resend wallet transactions that haven't gotten in a block yet
          ResendWalletTransactions();
  
          // Address refresh broadcast
          static int64 nLastRebroadcast;
          if (!IsInitialBlockDownload() && (GetTime() - nLastRebroadcast > 24 * 60 * 60))
          {
              {
                  LOCK(cs_vNodes);
                  BOOST_FOREACH(CNode* pnode, vNodes)
                  {
                      // Periodically clear setAddrKnown to allow refresh broadcasts
                      if (nLastRebroadcast)
                          pnode->setAddrKnown.clear();
  
                      // Rebroadcast our address
                      if (!fNoListen)
                      {
                          CAddress addr = GetLocalAddress(&pnode->addr);
                          if (addr.IsRoutable())
                              pnode->PushAddress(addr);
                      }
                  }
              }
              nLastRebroadcast = GetTime();
          }
  
          //
          // Message: addr
          //
          if (fSendTrickle)
          {
              vector<CAddress> vAddr;
              vAddr.reserve(pto->vAddrToSend.size());
              BOOST_FOREACH(const CAddress& addr, pto->vAddrToSend)
              {
                  // returns true if wasn't already contained in the set
                  if (pto->setAddrKnown.insert(addr).second)
                  {
                      vAddr.push_back(addr);
                      // receiver rejects addr messages larger than 1000
                      if (vAddr.size() >= 1000)
                      {
                          pto->PushMessage("addr", vAddr);
                          vAddr.clear();
                      }
                  }
              }
              pto->vAddrToSend.clear();
              if (!vAddr.empty())
                  pto->PushMessage("addr", vAddr);
          }
  
  
          //
          // Message: inventory
          //
          vector<CInv> vInv;
          vector<CInv> vInvWait;
          {
              LOCK(pto->cs_inventory);
              vInv.reserve(pto->vInventoryToSend.size());
              vInvWait.reserve(pto->vInventoryToSend.size());
              BOOST_FOREACH(const CInv& inv, pto->vInventoryToSend)
              {
                  if (pto->setInventoryKnown.count(inv))
                      continue;
  
                  // trickle out tx inv to protect privacy
                  if (inv.type == MSG_TX && !fSendTrickle)
                  {
                      // 1/4 of tx invs blast to all immediately
                      static uint256 hashSalt;
                      if (hashSalt == 0)
                          hashSalt = GetRandHash();
                      uint256 hashRand = inv.hash ^ hashSalt;
                      hashRand = Hash(BEGIN(hashRand), END(hashRand));
                      bool fTrickleWait = ((hashRand & 3) != 0);
  
                      // always trickle our own transactions
                      if (!fTrickleWait)
                      {
                          CWalletTx wtx;
                          if (GetTransaction(inv.hash, wtx))
                              if (wtx.fFromMe)
                                  fTrickleWait = true;
                      }
  
                      if (fTrickleWait)
                      {
                          vInvWait.push_back(inv);
                          continue;
                      }
                  }
  
                  // returns true if wasn't already contained in the set
                  if (pto->setInventoryKnown.insert(inv).second)
                  {
                      vInv.push_back(inv);
                      if (vInv.size() >= 1000)
                      {
                          pto->PushMessage("inv", vInv);
                          vInv.clear();
                      }
                  }
              }
              pto->vInventoryToSend = vInvWait;
          }
          if (!vInv.empty())
              pto->PushMessage("inv", vInv);
  
  
          //
          // Message: getdata
          //
          vector<CInv> vGetData;
          int64 nNow = GetTime() * 1000000;
          CTxDB txdb("r");
          while (!pto->mapAskFor.empty() && (*pto->mapAskFor.begin()).first <= nNow)
          {
              const CInv& inv = (*pto->mapAskFor.begin()).second;
              if (!AlreadyHave(txdb, inv))
              {
                  if (fDebugNet)
                      printf("sending getdata: %s\n", inv.ToString().c_str());
                  vGetData.push_back(inv);
                  if (vGetData.size() >= 1000)
                  {
                      pto->PushMessage("getdata", vGetData);
                      vGetData.clear();
                  }
                  mapAlreadyAskedFor[inv] = nNow;
              }
              pto->mapAskFor.erase(pto->mapAskFor.begin());
          }
          if (!vGetData.empty())
              pto->PushMessage("getdata", vGetData);
  
      }
      return true;
  }
  
  
  
  
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // BitcoinMiner
  //
  
  int static FormatHashBlocks(void* pbuffer, unsigned int len)
  {
      unsigned char* pdata = (unsigned char*)pbuffer;
      unsigned int blocks = 1 + ((len + 8) / 64);
      unsigned char* pend = pdata + 64 * blocks;
      memset(pdata + len, 0, 64 * blocks - len);
      pdata[len] = 0x80;
      unsigned int bits = len * 8;
      pend[-1] = (bits >> 0) & 0xff;
      pend[-2] = (bits >> 8) & 0xff;
      pend[-3] = (bits >> 16) & 0xff;
      pend[-4] = (bits >> 24) & 0xff;
      return blocks;
  }
  
  static const unsigned int pSHA256InitState[8] =
  {0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a, 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19};
  
  void SHA256Transform(void* pstate, void* pinput, const void* pinit)
  {
      SHA256_CTX ctx;
      unsigned char data[64];
  
      SHA256_Init(&ctx);
  
      for (int i = 0; i < 16; i++)
          ((uint32_t*)data)[i] = ByteReverse(((uint32_t*)pinput)[i]);
  
      for (int i = 0; i < 8; i++)
          ctx.h[i] = ((uint32_t*)pinit)[i];
  
      SHA256_Update(&ctx, data, sizeof(data));
      for (int i = 0; i < 8; i++)
          ((uint32_t*)pstate)[i] = ctx.h[i];
  }
  
  // Some explaining would be appreciated
  class COrphan
  {
  public:
      CTransaction* ptx;
      set<uint256> setDependsOn;
      double dPriority;
      double dFeePerKb;
  
      COrphan(CTransaction* ptxIn)
      {
          ptx = ptxIn;
          dPriority = dFeePerKb = 0;
      }
  
      void print() const
      {
          printf("COrphan(hash=%s, dPriority=%.1f, dFeePerKb=%.1f)\n",
                 ptx->GetHash().ToString().substr(0,10).c_str(), dPriority, dFeePerKb);
          BOOST_FOREACH(uint256 hash, setDependsOn)
              printf("   setDependsOn %s\n", hash.ToString().substr(0,10).c_str());
      }
  };
  
  
  uint64 nLastBlockTx = 0;
  uint64 nLastBlockSize = 0;
  int64 nLastCoinStakeSearchInterval = 0;
   
  // We want to sort transactions by priority and fee, so:
  typedef boost::tuple<double, double, CTransaction*> TxPriority;
  class TxPriorityCompare
  {
      bool byFee;
  public:
      TxPriorityCompare(bool _byFee) : byFee(_byFee) { }
      bool operator()(const TxPriority& a, const TxPriority& b)
      {
          if (byFee)
          {
              if (a.get<1>() == b.get<1>())
                  return a.get<0>() < b.get<0>();
              return a.get<1>() < b.get<1>();
          }
          else
          {
              if (a.get<0>() == b.get<0>())
                  return a.get<1>() < b.get<1>();
              return a.get<0>() < b.get<0>();
          }
      }
  };
  
  // CreateNewBlock:
  //   fProofOfStake: try (best effort) to make a proof-of-stake block
  CBlock* CreateNewBlock(CWallet* pwallet, bool fProofOfStake)
  {
      CReserveKey reservekey(pwallet);
  
      // Create new block
      auto_ptr<CBlock> pblock(new CBlock());
      if (!pblock.get())
          return NULL;
  
      // Create coinbase tx
      CTransaction txNew;
      txNew.vin.resize(1);
      txNew.vin[0].prevout.SetNull();
      txNew.vout.resize(1);
      txNew.vout[0].scriptPubKey << reservekey.GetReservedKey() << OP_CHECKSIG;
  
      // Add our coinbase tx as first transaction
      pblock->vtx.push_back(txNew);
  
      // Largest block you're willing to create:
      unsigned int nBlockMaxSize = GetArg("-blockmaxsize", MAX_BLOCK_SIZE_GEN/2);
      // Limit to betweeen 1K and MAX_BLOCK_SIZE-1K for sanity:
      nBlockMaxSize = std::max((unsigned int)1000, std::min((unsigned int)(MAX_BLOCK_SIZE-1000), nBlockMaxSize));
  
      // How much of the block should be dedicated to high-priority transactions,
      // included regardless of the fees they pay
      unsigned int nBlockPrioritySize = GetArg("-blockprioritysize", 27000);
      nBlockPrioritySize = std::min(nBlockMaxSize, nBlockPrioritySize);
  
      // Minimum block size you want to create; block will be filled with free transactions
      // until there are no more or the block reaches this size:
      unsigned int nBlockMinSize = GetArg("-blockminsize", 0);
      nBlockMinSize = std::min(nBlockMaxSize, nBlockMinSize);
  
      // Fee-per-kilobyte amount considered the same as "free"
      // Be careful setting this: if you set it to zero then
      // a transaction spammer can cheaply fill blocks using
      // 1-satoshi-fee transactions. It should be set above the real
      // cost to you of processing a transaction.
      int64 nMinTxFee = MIN_TX_FEE;
      if (mapArgs.count("-mintxfee"))
          ParseMoney(mapArgs["-mintxfee"], nMinTxFee);
  
      // ppcoin: if coinstake available add coinstake tx
      static int64 nLastCoinStakeSearchTime = GetAdjustedTime();  // only initialized at startup
      CBlockIndex* pindexPrev = pindexBest;
  
      if (fProofOfStake)  // attempt to find a coinstake
      {
          pblock->nBits = GetNextTargetRequired(pindexPrev, true);
          CTransaction txCoinStake;
          int64 nSearchTime = txCoinStake.nTime; // search to current time
          if (nSearchTime > nLastCoinStakeSearchTime)
          {
  			// printf(">>> OK1\n");
              if (pwallet->CreateCoinStake(*pwallet, pblock->nBits, nSearchTime-nLastCoinStakeSearchTime, txCoinStake))
              {
  				if (txCoinStake.nTime >= max(pindexPrev->GetMedianTimePast()+1, pindexPrev->GetBlockTime() - nMaxClockDrift))
                  {   // make sure coinstake would meet timestamp protocol
                      // as it would be the same as the block timestamp
                      pblock->vtx[0].vout[0].SetEmpty();
                      pblock->vtx[0].nTime = txCoinStake.nTime;
                      pblock->vtx.push_back(txCoinStake);
                  }
              }
              nLastCoinStakeSearchInterval = nSearchTime - nLastCoinStakeSearchTime;
              nLastCoinStakeSearchTime = nSearchTime;
          }
      }
  
      pblock->nBits = GetNextTargetRequired(pindexPrev, pblock->IsProofOfStake());
  
      // Collect memory pool transactions into the block
      int64 nFees = 0;
      {
          LOCK2(cs_main, mempool.cs);
          CBlockIndex* pindexPrev = pindexBest;
          CTxDB txdb("r");
  
          // Priority order to process transactions
          list<COrphan> vOrphan; // list memory doesn't move
          map<uint256, vector<COrphan*> > mapDependers;
  
          // This vector will be sorted into a priority queue:
          vector<TxPriority> vecPriority;
          vecPriority.reserve(mempool.mapTx.size());
          for (map<uint256, CTransaction>::iterator mi = mempool.mapTx.begin(); mi != mempool.mapTx.end(); ++mi)
          {
              CTransaction& tx = (*mi).second;
              if (tx.IsCoinBase() || tx.IsCoinStake() || !tx.IsFinal())
                  continue;
  
              COrphan* porphan = NULL;
              double dPriority = 0;
              int64 nTotalIn = 0;
              bool fMissingInputs = false;
              BOOST_FOREACH(const CTxIn& txin, tx.vin)
              {
                  // Read prev transaction
                  CTransaction txPrev;
                  CTxIndex txindex;
                  if (!txPrev.ReadFromDisk(txdb, txin.prevout, txindex))
                  {
                      // This should never happen; all transactions in the memory
                      // pool should connect to either transactions in the chain
                      // or other transactions in the memory pool.
                      if (!mempool.mapTx.count(txin.prevout.hash))
                      {
                          printf("ERROR: mempool transaction missing input\n");
                          if (fDebug) assert("mempool transaction missing input" == 0);
                          fMissingInputs = true;
                          if (porphan)
                              vOrphan.pop_back();
                          break;
                      }
  
                      // Has to wait for dependencies
                      if (!porphan)
                      {
                          // Use list for automatic deletion
                          vOrphan.push_back(COrphan(&tx));
                          porphan = &vOrphan.back();
                      }
                      mapDependers[txin.prevout.hash].push_back(porphan);
                      porphan->setDependsOn.insert(txin.prevout.hash);
                      nTotalIn += mempool.mapTx[txin.prevout.hash].vout[txin.prevout.n].nValue;
                      continue;
                  }
                  int64 nValueIn = txPrev.vout[txin.prevout.n].nValue;
                  nTotalIn += nValueIn;
  
                  int nConf = txindex.GetDepthInMainChain();
                  dPriority += (double)nValueIn * nConf;
              }
              if (fMissingInputs) continue;
  
              // Priority is sum(valuein * age) / txsize
              unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
              dPriority /= nTxSize;
  
              // This is a more accurate fee-per-kilobyte than is used by the client code, because the
              // client code rounds up the size to the nearest 1K. That's good, because it gives an
              // incentive to create smaller transactions.
              double dFeePerKb =  double(nTotalIn-tx.GetValueOut()) / (double(nTxSize)/1000.0);
  
              if (porphan)
              {
                  porphan->dPriority = dPriority;
                  porphan->dFeePerKb = dFeePerKb;
              }
              else
                  vecPriority.push_back(TxPriority(dPriority, dFeePerKb, &(*mi).second));
          }
  
          // Collect transactions into block
          map<uint256, CTxIndex> mapTestPool;
          uint64 nBlockSize = 1000;
          uint64 nBlockTx = 0;
          int nBlockSigOps = 100;
          bool fSortedByFee = (nBlockPrioritySize <= 0);
  
          TxPriorityCompare comparer(fSortedByFee);
          std::make_heap(vecPriority.begin(), vecPriority.end(), comparer);
  
          while (!vecPriority.empty())
          {
              // Take highest priority transaction off the priority queue:
              double dPriority = vecPriority.front().get<0>();
              double dFeePerKb = vecPriority.front().get<1>();
              CTransaction& tx = *(vecPriority.front().get<2>());
  
              std::pop_heap(vecPriority.begin(), vecPriority.end(), comparer);
              vecPriority.pop_back();
  
              // Size limits
              unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
              if (nBlockSize + nTxSize >= nBlockMaxSize)
                  continue;
  
              // Legacy limits on sigOps:
              unsigned int nTxSigOps = tx.GetLegacySigOpCount();
              if (nBlockSigOps + nTxSigOps >= MAX_BLOCK_SIGOPS)
                  continue;
  
              // Timestamp limit
              if (tx.nTime > GetAdjustedTime() || (pblock->IsProofOfStake() && tx.nTime > pblock->vtx[1].nTime))
                  continue;
  
              // ppcoin: simplify transaction fee - allow free = false
              int64 nMinFee = tx.GetMinFee(nBlockSize, false, GMF_BLOCK);
  
              // Skip free transactions if we're past the minimum block size:
              if (fSortedByFee && (dFeePerKb < nMinTxFee) && (nBlockSize + nTxSize >= nBlockMinSize))
                  continue;
  
              // Prioritize by fee once past the priority size or we run out of high-priority
              // transactions:
              if (!fSortedByFee &&
                  ((nBlockSize + nTxSize >= nBlockPrioritySize) || (dPriority < COIN * 144 / 250)))
              {
                  fSortedByFee = true;
                  comparer = TxPriorityCompare(fSortedByFee);
                  std::make_heap(vecPriority.begin(), vecPriority.end(), comparer);
              }
  
              // Connecting shouldn't fail due to dependency on other memory pool transactions
              // because we're already processing them in order of dependency
              map<uint256, CTxIndex> mapTestPoolTmp(mapTestPool);
              MapPrevTx mapInputs;
              bool fInvalid;
              if (!tx.FetchInputs(txdb, mapTestPoolTmp, false, true, mapInputs, fInvalid))
                  continue;
  
              int64 nTxFees = tx.GetValueIn(mapInputs)-tx.GetValueOut();
              if (nTxFees < nMinFee)
                  continue;
  
              nTxSigOps += tx.GetP2SHSigOpCount(mapInputs);
              if (nBlockSigOps + nTxSigOps >= MAX_BLOCK_SIGOPS)
                  continue;
  
              if (!tx.ConnectInputs(txdb, mapInputs, mapTestPoolTmp, CDiskTxPos(1,1,1), pindexPrev, false, true))
                  continue;
              mapTestPoolTmp[tx.GetHash()] = CTxIndex(CDiskTxPos(1,1,1), tx.vout.size());
              swap(mapTestPool, mapTestPoolTmp);
  
              // Added
              pblock->vtx.push_back(tx);
              nBlockSize += nTxSize;
              ++nBlockTx;
              nBlockSigOps += nTxSigOps;
              nFees += nTxFees;
  
              if (fDebug && GetBoolArg("-printpriority"))
              {
                  printf("priority %.1f feeperkb %.1f txid %s\n",
                         dPriority, dFeePerKb, tx.GetHash().ToString().c_str());
              }
  
              // Add transactions that depend on this one to the priority queue
              uint256 hash = tx.GetHash();
              if (mapDependers.count(hash))
              {
                  BOOST_FOREACH(COrphan* porphan, mapDependers[hash])
                  {
                      if (!porphan->setDependsOn.empty())
                      {
                          porphan->setDependsOn.erase(hash);
                          if (porphan->setDependsOn.empty())
                          {
                              vecPriority.push_back(TxPriority(porphan->dPriority, porphan->dFeePerKb, porphan->ptx));
                              std::push_heap(vecPriority.begin(), vecPriority.end(), comparer);
                          }
                      }
                  }
              }
          }
  
          nLastBlockTx = nBlockTx;
          nLastBlockSize = nBlockSize;
  
          if (fDebug && GetBoolArg("-printpriority"))
              printf("CreateNewBlock(): total size %"PRI64u"\n", nBlockSize);
  
          if (pblock->IsProofOfWork())
              pblock->vtx[0].vout[0].nValue = GetProofOfWorkReward(pindexPrev->nHeight+1, nFees, pindexPrev);
  
          // Fill in header
          pblock->hashPrevBlock  = pindexPrev->GetBlockHash();
          if (pblock->IsProofOfStake())
              pblock->nTime      = pblock->vtx[1].nTime; //same as coinstake timestamp
          pblock->nTime          = max(pindexPrev->GetMedianTimePast()+1, pblock->GetMaxTransactionTime());
          pblock->nTime          = max(pblock->GetBlockTime(), pindexPrev->GetBlockTime() - nMaxClockDrift);
          if (pblock->IsProofOfWork())
              pblock->UpdateTime(pindexPrev);
          pblock->nNonce         = 0;
      }
  
      return pblock.release();
  }
  
  
  void IncrementExtraNonce(CBlock* pblock, CBlockIndex* pindexPrev, unsigned int& nExtraNonce)
  {
      // Update nExtraNonce
      static uint256 hashPrevBlock;
      if (hashPrevBlock != pblock->hashPrevBlock)
      {
          nExtraNonce = 0;
          hashPrevBlock = pblock->hashPrevBlock;
      }
      ++nExtraNonce;
      unsigned int nHeight = pindexPrev->nHeight+1; // Height first in coinbase required for block.version=2
      pblock->vtx[0].vin[0].scriptSig = (CScript() << nHeight << CBigNum(nExtraNonce)) + COINBASE_FLAGS;
      assert(pblock->vtx[0].vin[0].scriptSig.size() <= 100);
  
      pblock->hashMerkleRoot = pblock->BuildMerkleTree();
  }
  
  
  void FormatHashBuffers(CBlock* pblock, char* pmidstate, char* pdata, char* phash1)
  {
      //
      // Pre-build hash buffers
      //
      struct
      {
          struct unnamed2
          {
              int nVersion;
              uint256 hashPrevBlock;
              uint256 hashMerkleRoot;
              unsigned int nTime;
              unsigned int nBits;
              unsigned int nNonce;
          }
          block;
          unsigned char pchPadding0[64];
          uint256 hash1;
          unsigned char pchPadding1[64];
      }
      tmp;
      memset(&tmp, 0, sizeof(tmp));
  
      tmp.block.nVersion       = pblock->nVersion;
      tmp.block.hashPrevBlock  = pblock->hashPrevBlock;
      tmp.block.hashMerkleRoot = pblock->hashMerkleRoot;
      tmp.block.nTime          = pblock->nTime;
      tmp.block.nBits          = pblock->nBits;
      tmp.block.nNonce         = pblock->nNonce;
  
      FormatHashBlocks(&tmp.block, sizeof(tmp.block));
      FormatHashBlocks(&tmp.hash1, sizeof(tmp.hash1));
  
      // Byte swap all the input buffer
      for (unsigned int i = 0; i < sizeof(tmp)/4; i++)
          ((unsigned int*)&tmp)[i] = ByteReverse(((unsigned int*)&tmp)[i]);
  
      // Precalc the first half of the first hash, which stays constant
      SHA256Transform(pmidstate, &tmp.block, pSHA256InitState);
  
      memcpy(pdata, &tmp.block, 128);
      memcpy(phash1, &tmp.hash1, 64);
  }
  
  
  bool CheckWork(CBlock* pblock, CWallet& wallet, CReserveKey& reservekey)
  {
      uint256 hash = pblock->GetHash();
      uint256 hashTarget = CBigNum().SetCompact(pblock->nBits).getuint256();
  
      if (hash > hashTarget && pblock->IsProofOfWork())
          return error("BitcoinMiner : proof-of-work not meeting target");
  
      //// debug print
      printf("BitcoinMiner:\n");
      printf("new block found  \n  hash: %s  \ntarget: %s\n", hash.GetHex().c_str(), hashTarget.GetHex().c_str());
      pblock->print();
      printf("generated %s\n", FormatMoney(pblock->vtx[0].vout[0].nValue).c_str());
  
      // Found a solution
      {
          LOCK(cs_main);
          if (pblock->hashPrevBlock != hashBestChain)
              return error("BitcoinMiner : generated block is stale");
  
          // Remove key from key pool
          reservekey.KeepKey();
  
          // Track how many getdata requests this block gets
          {
              LOCK(wallet.cs_wallet);
              wallet.mapRequestCount[pblock->GetHash()] = 0;
          }
  
          // Process this block the same as if we had received it from another node
          if (!ProcessBlock(NULL, pblock))
              return error("BitcoinMiner : ProcessBlock, block not accepted");
      }
  
      return true;
  }
  
  void static ThreadBitcoinMiner(void* parg);
  
  static bool fGenerateBitcoins = false;
  static bool fLimitProcessors = false;
  static int nLimitProcessors = -1;
  
  void BitcoinMiner(CWallet *pwallet, bool fProofOfStake)
  {
      printf("CPUMiner started for proof-of-%s\n", fProofOfStake? "stake" : "work");
      SetThreadPriority(THREAD_PRIORITY_LOWEST);
  
      // Make this thread recognisable as the mining thread
      RenameThread("bitcoin-miner");
  
      // Each thread has its own key and counter
      CReserveKey reservekey(pwallet);
      unsigned int nExtraNonce = 0;
  
      while (fGenerateBitcoins || fProofOfStake)
      {
          if (fShutdown)
              return;
  
          while (vNodes.empty() || IsInitialBlockDownload() || pwallet->IsLocked())
          {
              nLastCoinStakeSearchInterval = 0;
              Sleep(1000);
              if (fShutdown)
                  return;
              if (!fGenerateBitcoins && !fProofOfStake)
                  return;
          }
  
          //
          // Create new block
          //
          unsigned int nTransactionsUpdatedLast = nTransactionsUpdated;
          CBlockIndex* pindexPrev = pindexBest;
  
          auto_ptr<CBlock> pblock(CreateNewBlock(pwallet, fProofOfStake));
          if (!pblock.get())
              return;
          IncrementExtraNonce(pblock.get(), pindexPrev, nExtraNonce);
  
          if (fProofOfStake)
          {
              // ppcoin: if proof-of-stake block found then process block
              if (pblock->IsProofOfStake())
              {
                  if (!pblock->SignBlock(*pwalletMain))
                      continue;
                  printf("CPUMiner : proof-of-stake block found %s\n", pblock->GetHash().ToString().c_str()); 
                  SetThreadPriority(THREAD_PRIORITY_NORMAL);
                  CheckWork(pblock.get(), *pwalletMain, reservekey);
                  SetThreadPriority(THREAD_PRIORITY_LOWEST);
              }
              Sleep(250);
              continue;
          }
  
          printf("Running BitcoinMiner with %"PRIszu" transactions in block (%u bytes)\n", pblock->vtx.size(),
                 ::GetSerializeSize(*pblock, SER_NETWORK, PROTOCOL_VERSION));
  
          //
          // Pre-build hash buffers
          //
          //char pmidstatebuf[32+16]; char* pmidstate = alignup<16>(pmidstatebuf);
          //char pdatabuf[128+16];    char* pdata     = alignup<16>(pdatabuf);
          //char phash1buf[64+16];    char* phash1    = alignup<16>(phash1buf);
  
          //FormatHashBuffers(pblock.get(), pmidstate, pdata, phash1);
  
          //unsigned int& nBlockTime = *(unsigned int*)(pdata + 64 + 4);
          //unsigned int& nBlockNonce = *(unsigned int*)(pdata + 64 + 12);
  
  
          //
          // Search
          //
          int64 nStart = GetTime();
          uint256 hashTarget = CBigNum().SetCompact(pblock->nBits).getuint256();
  	uint256 hash;
  
          loop
          {
  	    hash = pblock->GetHash();
              if (hash <= hashTarget){
                  // nHashesDone += pblock->nNonce;
                  if (!pblock->SignBlock(*pwalletMain))
                      break;
  
                  SetThreadPriority(THREAD_PRIORITY_NORMAL);
  
                  printf("proof-of-work found \n hash: %s \ntarget: %s\n", hash.GetHex().c_str(), hashTarget.GetHex().c_str());
                  pblock->print();
  
                  CheckWork(pblock.get(), *pwalletMain, reservekey);
                  SetThreadPriority(THREAD_PRIORITY_LOWEST);
                  break;
              }
              ++pblock->nNonce;
  
  
              // Meter hashes/sec
              static int64 nHashCounter;
              if (nHPSTimerStart == 0)
              {
                  nHPSTimerStart = GetTimeMillis();
                  nHashCounter = 0;
              }
              else
                  nHashCounter += 1;
  
              if (GetTimeMillis() - nHPSTimerStart > 4000)
              {
                  static CCriticalSection cs;
                  {
                      LOCK(cs);
                      if (GetTimeMillis() - nHPSTimerStart > 4000)
                      {
                          dHashesPerSec = 1000.0 * nHashCounter / (GetTimeMillis() - nHPSTimerStart);
                          nHPSTimerStart = GetTimeMillis();
                          nHashCounter = 0;
                          
                              printf("hashmeter %3d CPUs %6.0f khash/s\n", vnThreadsRunning[THREAD_MINER], dHashesPerSec/1000.0);
                          
                      }
                  }
              }
  
              // Check for stop or if block needs to be rebuilt
              if (fShutdown)
                  return;
              if (!fGenerateBitcoins)
                  return;
              if (fLimitProcessors && vnThreadsRunning[THREAD_MINER] > nLimitProcessors)
                  return;
              if (vNodes.empty())
                  break;
              if (++pblock->nNonce >= 0xffff0000)
                  break;
              if (nTransactionsUpdated != nTransactionsUpdatedLast && GetTime() - nStart > 60)
                  break;
              if (pindexPrev != pindexBest)
                  break;
  
              // Update nTime every few seconds
              pblock->nTime = max(pindexPrev->GetMedianTimePast()+1, pblock->GetMaxTransactionTime());
              pblock->nTime = max(pblock->GetBlockTime(), pindexPrev->GetBlockTime() - nMaxClockDrift);
              pblock->UpdateTime(pindexPrev);
  
              if (pblock->GetBlockTime() >= (int64)pblock->vtx[0].nTime + nMaxClockDrift)
                  break;  // need to update coinbase timestamp
          }
      }
  }
  
  void static ThreadBitcoinMiner(void* parg)
  {
      CWallet* pwallet = (CWallet*)parg;
      try
      {
          vnThreadsRunning[THREAD_MINER]++;
          BitcoinMiner(pwallet, false);
          vnThreadsRunning[THREAD_MINER]--;
      }
      catch (std::exception& e) {
          vnThreadsRunning[THREAD_MINER]--;
          PrintException(&e, "ThreadBitcoinMiner()");
      } catch (...) {
          vnThreadsRunning[THREAD_MINER]--;
          PrintException(NULL, "ThreadBitcoinMiner()");
      }
      nHPSTimerStart = 0;
      if (vnThreadsRunning[THREAD_MINER] == 0)
          dHashesPerSec = 0;
      printf("ThreadBitcoinMiner exiting, %d threads remaining\n", vnThreadsRunning[THREAD_MINER]);
  }
  
  
  void GenerateBitcoins(bool fGenerate, CWallet* pwallet)
  {
      fGenerateBitcoins = fGenerate;
      nLimitProcessors = GetArg("-genproclimit", -1);
      if (nLimitProcessors == 0)
          fGenerateBitcoins = false;
      fLimitProcessors = (nLimitProcessors != -1);
  
      if (fGenerate)
      {
          int nProcessors = boost::thread::hardware_concurrency();
          printf("%d processors\n", nProcessors);
          if (nProcessors < 1)
              nProcessors = 1;
          if (fLimitProcessors && nProcessors > nLimitProcessors)
              nProcessors = nLimitProcessors;
          int nAddThreads = nProcessors - vnThreadsRunning[THREAD_MINER];
          printf("Starting %d BitcoinMiner threads\n", nAddThreads);
          for (int i = 0; i < nAddThreads; i++)
          {
              if (!NewThread(ThreadBitcoinMiner, pwallet))
                  printf("Error: NewThread(ThreadBitcoinMiner) failed\n");
              Sleep(10);
          }
      }
  }
  