text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2014 The Bitcoin developers
  // Copyright (c) 2014-2015 The Talisman developers
  // Distributed under the MIT/X11 software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include "miner.h"
  
  #include "amount.h"
  #include "primitives/block.h"
  #include "primitives/transaction.h"
  #include "hash.h"
  #include "main.h"
  #include "net.h"
  #include "pow.h"
  #include "timedata.h"
  #include "util.h"
  #include "utilmoneystr.h"
  #ifdef ENABLE_WALLET
  #include "wallet.h"
  #endif
  #include "masternode-payments.h"
  
  #include <boost/thread.hpp>
  #include <boost/tuple/tuple.hpp>
  
  using namespace std;
  
  //////////////////////////////////////////////////////////////////////////////
  //
  // TalismanMiner
  //
  
  //
  // Unconfirmed transactions in the memory pool often depend on other
  // transactions in the memory pool. When we select transactions from the
  // pool, we select by highest priority or fee rate, so we might consider
  // transactions that depend on transactions that aren't yet in the block.
  // The COrphan class keeps track of these 'temporary orphans' while
  // CreateBlock is figuring out which transactions to include.
  //
  class COrphan
  {
  public:
      const CTransaction* ptx;
      set<uint256> setDependsOn;
      CFeeRate feeRate;
      double dPriority;
  
      COrphan(const CTransaction* ptxIn) : ptx(ptxIn), feeRate(0), dPriority(0)
      {
      }
  };
  
  uint64_t nLastBlockTx = 0;
  uint64_t nLastBlockSize = 0;
  
  // We want to sort transactions by priority and fee rate, so:
  typedef boost::tuple<double, CFeeRate, const 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>();
          }
      }
  };
  
  void UpdateTime(CBlockHeader* pblock, const CBlockIndex* pindexPrev)
  {
      pblock->nTime = std::max(pindexPrev->GetMedianTimePast()+1, GetAdjustedTime());
  
      // Updating time can change work required on testnet:
      if (Params().AllowMinDifficultyBlocks())
          pblock->nBits = GetNextWorkRequired(pindexPrev, pblock);
  }
  
  CBlockTemplate* CreateNewBlock(const CScript& scriptPubKeyIn)
  {
      // Create new block
      auto_ptr<CBlockTemplate> pblocktemplate(new CBlockTemplate());
      if(!pblocktemplate.get())
          return NULL;
      CBlock *pblock = &pblocktemplate->block; // pointer for convenience
  
      // -regtest only: allow overriding block.nVersion with
      // -blockversion=N to test forking scenarios
      if (Params().MineBlocksOnDemand())
          pblock->nVersion = GetArg("-blockversion", pblock->nVersion);
  
      // Create coinbase tx
      CMutableTransaction txNew;
      txNew.vin.resize(1);
      txNew.vin[0].prevout.SetNull();
      txNew.vout.resize(1);
      txNew.vout[0].scriptPubKey = scriptPubKeyIn;
  
      // Largest block you're willing to create:
      unsigned int nBlockMaxSize = GetArg("-blockmaxsize", DEFAULT_BLOCK_MAX_SIZE);
      // 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", DEFAULT_BLOCK_PRIORITY_SIZE);
      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", DEFAULT_BLOCK_MIN_SIZE);
      nBlockMinSize = std::min(nBlockMaxSize, nBlockMinSize);
  
      // Collect memory pool transactions into the block
      CAmount nFees = 0;
  
      {
          LOCK2(cs_main, mempool.cs);
  
          CBlockIndex* pindexPrev = chainActive.Tip();
          const int nHeight = pindexPrev->nHeight + 1;
          CCoinsViewCache view(pcoinsTip);
  
          // Add our coinbase tx as first transaction
          pblock->vtx.push_back(txNew);
          pblocktemplate->vTxFees.push_back(-1); // updated at end
          pblocktemplate->vTxSigOps.push_back(-1); // updated at end
  
          // Priority order to process transactions
          list<COrphan> vOrphan; // list memory doesn't move
          map<uint256, vector<COrphan*> > mapDependers;
          bool fPrintPriority = GetBoolArg("-printpriority", false);
  
          // This vector will be sorted into a priority queue:
          vector<TxPriority> vecPriority;
          vecPriority.reserve(mempool.mapTx.size());
          for (map<uint256, CTxMemPoolEntry>::iterator mi = mempool.mapTx.begin();
               mi != mempool.mapTx.end(); ++mi)
          {
              const CTransaction& tx = mi->second.GetTx();
              if (tx.IsCoinBase() || !IsFinalTx(tx, nHeight))
                  continue;
  
              COrphan* porphan = NULL;
              double dPriority = 0;
              CAmount nTotalIn = 0;
              bool fMissingInputs = false;
              BOOST_FOREACH(const CTxIn& txin, tx.vin)
              {
                  // Read prev transaction
                  if (!view.HaveCoins(txin.prevout.hash))
                  {
                      // 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))
                      {
                          LogPrintf("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].GetTx().vout[txin.prevout.n].nValue;
                      continue;
                  }
                  const CCoins* coins = view.AccessCoins(txin.prevout.hash);
                  assert(coins);
  
                  CAmount nValueIn = coins->vout[txin.prevout.n].nValue;
                  nTotalIn += nValueIn;
  
                  int nConf = nHeight - coins->nHeight;
  
                  dPriority += (double)nValueIn * nConf;
              }
              if (fMissingInputs) continue;
  
              // Priority is sum(valuein * age) / modified_txsize
              unsigned int nTxSize = ::GetSerializeSize(tx, SER_NETWORK, PROTOCOL_VERSION);
              dPriority = tx.ComputePriority(dPriority, nTxSize);
  
              uint256 hash = tx.GetHash();
              mempool.ApplyDeltas(hash, dPriority, nTotalIn);
  
              CFeeRate feeRate(nTotalIn-tx.GetValueOut(), nTxSize);
  
              if (porphan)
              {
                  porphan->dPriority = dPriority;
                  porphan->feeRate = feeRate;
              }
              else
                  vecPriority.push_back(TxPriority(dPriority, feeRate, &mi->second.GetTx()));
          }
  
          // Collect transactions into block
          uint64_t nBlockSize = 1000;
          uint64_t 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>();
              CFeeRate feeRate = vecPriority.front().get<1>();
              const 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 = GetLegacySigOpCount(tx);
              if (nBlockSigOps + nTxSigOps >= MAX_BLOCK_SIGOPS)
                  continue;
  
              // Skip free transactions if we're past the minimum block size:
              const uint256& hash = tx.GetHash();
              double dPriorityDelta = 0;
              CAmount nFeeDelta = 0;
              mempool.ApplyDeltas(hash, dPriorityDelta, nFeeDelta);
              if (fSortedByFee && (dPriorityDelta <= 0) && (nFeeDelta <= 0) && (feeRate < ::minRelayTxFee) && (nBlockSize + nTxSize >= nBlockMinSize))
                  continue;
  
              // Prioritise by fee once past the priority size or we run out of high-priority
              // transactions:
              if (!fSortedByFee &&
                  ((nBlockSize + nTxSize >= nBlockPrioritySize) || !AllowFree(dPriority)))
              {
                  fSortedByFee = true;
                  comparer = TxPriorityCompare(fSortedByFee);
                  std::make_heap(vecPriority.begin(), vecPriority.end(), comparer);
              }
  
              if (!view.HaveInputs(tx))
                  continue;
  
              CAmount nTxFees = view.GetValueIn(tx)-tx.GetValueOut();
  
              nTxSigOps += GetP2SHSigOpCount(tx, view);
              if (nBlockSigOps + nTxSigOps >= MAX_BLOCK_SIGOPS)
                  continue;
  
              // Note that flags: we don't want to set mempool/IsStandard()
              // policy here, but we still have to ensure that the block we
              // create only contains transactions that are valid in new blocks.
              CValidationState state;
              if (!CheckInputs(tx, state, view, true, MANDATORY_SCRIPT_VERIFY_FLAGS, true))
                  continue;
  
              CTxUndo txundo;
              UpdateCoins(tx, state, view, txundo, nHeight);
  
              // Added
              pblock->vtx.push_back(tx);
              pblocktemplate->vTxFees.push_back(nTxFees);
              pblocktemplate->vTxSigOps.push_back(nTxSigOps);
              nBlockSize += nTxSize;
              ++nBlockTx;
              nBlockSigOps += nTxSigOps;
              nFees += nTxFees;
  
              if (fPrintPriority)
              {
                  LogPrintf("priority %.1f fee %s txid %s\n",
                      dPriority, feeRate.ToString(), tx.GetHash().ToString());
              }
  
              // Add transactions that depend on this one to the priority queue
              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->feeRate, porphan->ptx));
                              std::push_heap(vecPriority.begin(), vecPriority.end(), comparer);
                          }
                      }
                  }
              }
          }
  
          // Masternode and general budget payments
          FillBlockPayee(txNew, nFees);
  
          // Make payee
  	    if(txNew.vout.size() > 1){
              pblock->payee = txNew.vout[1].scriptPubKey;
          }
  
          nLastBlockTx = nBlockTx;
          nLastBlockSize = nBlockSize;
          LogPrintf("CreateNewBlock(): total size %u\n", nBlockSize);
  
          // Compute final coinbase transaction.
          txNew.vin[0].scriptSig = CScript() << nHeight << OP_0;
          pblock->vtx[0] = txNew;
          pblocktemplate->vTxFees[0] = -nFees;
  
          // Fill in header
          pblock->hashPrevBlock  = pindexPrev->GetBlockHash();
          UpdateTime(pblock, pindexPrev);
          pblock->nBits          = GetNextWorkRequired(pindexPrev, pblock);
          pblock->nNonce         = 0;
          pblocktemplate->vTxSigOps[0] = GetLegacySigOpCount(pblock->vtx[0]);
  
          CValidationState state;
          if (!TestBlockValidity(state, *pblock, pindexPrev, false, false))
              throw std::runtime_error("CreateNewBlock() : TestBlockValidity failed");
      }
  
      return pblocktemplate.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
      CMutableTransaction txCoinbase(pblock->vtx[0]);
      txCoinbase.vin[0].scriptSig = (CScript() << nHeight << CScriptNum(nExtraNonce)) + COINBASE_FLAGS;
      assert(txCoinbase.vin[0].scriptSig.size() <= 100);
  
      pblock->vtx[0] = txCoinbase;
      pblock->hashMerkleRoot = pblock->BuildMerkleTree();
  }
  
  #ifdef ENABLE_WALLET
  //////////////////////////////////////////////////////////////////////////////
  //
  // Internal miner
  //
  double dHashesPerSec = 0.0;
  int64_t nHPSTimerStart = 0;
  
  // ***TODO*** ScanHash is not yet used in Talisman
  //
  // ScanHash scans nonces looking for a hash with at least some zero bits.
  // The nonce is usually preserved between calls, but periodically or if the
  // nonce is 0xffff0000 or above, the block is rebuilt and nNonce starts over at
  // zero.
  //
  //bool static ScanHash(const CBlockHeader *pblock, uint32_t& nNonce, uint256 *phash)
  //{
  //    // Write the first 76 bytes of the block header to a double-SHA256 state.
  //    CHash256 hasher;
  //    CDataStream ss(SER_NETWORK, PROTOCOL_VERSION);
  //    ss << *pblock;
  //    assert(ss.size() == 80);
  //    hasher.Write((unsigned char*)&ss[0], 76);
  
  //    while (true) {
  //        nNonce++;
  
  //        // Write the last 4 bytes of the block header (the nonce) to a copy of
  //        // the double-SHA256 state, and compute the result.
  //        CHash256(hasher).Write((unsigned char*)&nNonce, 4).Finalize((unsigned char*)phash);
  
  //        // Return the nonce if the hash has at least some zero bits,
  //        // caller will check if it has enough to reach the target
  //        if (((uint16_t*)phash)[15] == 0)
  //            return true;
  
  //        // If nothing found after trying for a while, return -1
  //        if ((nNonce & 0xffff) == 0)
  //            return false;
  //        if ((nNonce & 0xfff) == 0)
  //            boost::this_thread::interruption_point();
  //    }
  //}
  
  CBlockTemplate* CreateNewBlockWithKey(CReserveKey& reservekey)
  {
      CPubKey pubkey;
      if (!reservekey.GetReservedKey(pubkey))
          return NULL;
  
      CScript scriptPubKey = CScript() << ToByteVector(pubkey) << OP_CHECKSIG;
      return CreateNewBlock(scriptPubKey);
  }
  
  bool ProcessBlockFound(CBlock* pblock, CWallet& wallet, CReserveKey& reservekey)
  {
      LogPrintf("%s\n", pblock->ToString());
      LogPrintf("generated %s\n", FormatMoney(pblock->vtx[0].vout[0].nValue));
  
      // Found a solution
      {
          LOCK(cs_main);
          if (pblock->hashPrevBlock != chainActive.Tip()->GetBlockHash())
              return error("TalismanMiner : 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
      CValidationState state;
      if (!ProcessNewBlock(state, NULL, pblock))
          return error("TalismanMiner : ProcessNewBlock, block not accepted");
  
      return true;
  }
  
  // ***TODO*** that part changed in bitcoin, we are using a mix with old one here for now
  void static BitcoinMiner(CWallet *pwallet)
  {
      LogPrintf("TalismanMiner started\n");
      SetThreadPriority(THREAD_PRIORITY_LOWEST);
      RenameThread("talisman-miner");
  
      // Each thread has its own key and counter
      CReserveKey reservekey(pwallet);
      unsigned int nExtraNonce = 0;
  
      try {
          while (true) {
              if (Params().MiningRequiresPeers()) {
                  // Busy-wait for the network to come online so we don't waste time mining
                  // on an obsolete chain. In regtest mode we expect to fly solo.
                  do {
                      bool fvNodesEmpty;
                      {
                          LOCK(cs_vNodes);
                          fvNodesEmpty = vNodes.empty();
                      }
                      if (!fvNodesEmpty && !IsInitialBlockDownload())
                          break;
                      MilliSleep(1000);
                  } while (true);
              }
  
              //
              // Create new block
              //
              unsigned int nTransactionsUpdatedLast = mempool.GetTransactionsUpdated();
              CBlockIndex* pindexPrev = chainActive.Tip();
              if(!pindexPrev) break;
  
              auto_ptr<CBlockTemplate> pblocktemplate(CreateNewBlockWithKey(reservekey));
              if (!pblocktemplate.get())
              {
                  LogPrintf("Error in TalismanMiner: Keypool ran out, please call keypoolrefill before restarting the mining thread\n");
                  return;
              }
              CBlock *pblock = &pblocktemplate->block;
              IncrementExtraNonce(pblock, pindexPrev, nExtraNonce);
  
              LogPrintf("Running TalismanMiner with %u transactions in block (%u bytes)\n", pblock->vtx.size(),
                  ::GetSerializeSize(*pblock, SER_NETWORK, PROTOCOL_VERSION));
  
              //
              // Search
              //
              int64_t nStart = GetTime();
              uint256 hashTarget = uint256().SetCompact(pblock->nBits);
              while (true)
              {
                  unsigned int nHashesDone = 0;
  
                  uint256 hash;
                  while (true)
                  {
                      hash = pblock->GetHash();
                      if (hash <= hashTarget)
                      {
                          // Found a solution
                          SetThreadPriority(THREAD_PRIORITY_NORMAL);
                          LogPrintf("BitcoinMiner:\n");
                          LogPrintf("proof-of-work found  \n  hash: %s  \ntarget: %s\n", hash.GetHex(), hashTarget.GetHex());
                          ProcessBlockFound(pblock, *pwallet, reservekey);
                          SetThreadPriority(THREAD_PRIORITY_LOWEST);
  
                          // In regression test mode, stop mining after a block is found. This
                          // allows developers to controllably generate a block on demand.
                          if (Params().MineBlocksOnDemand())
                              throw boost::thread_interrupted();
  
                          break;
                      }
                      pblock->nNonce += 1;
                      nHashesDone += 1;
                      if ((pblock->nNonce & 0xFF) == 0)
                          break;
                  }
  
                  // Meter hashes/sec
                  static int64_t nHashCounter;
                  if (nHPSTimerStart == 0)
                  {
                      nHPSTimerStart = GetTimeMillis();
                      nHashCounter = 0;
                  }
                  else
                      nHashCounter += nHashesDone;
                  if (GetTimeMillis() - nHPSTimerStart > 4000)
                  {
                      static CCriticalSection cs;
                      {
                          LOCK(cs);
                          if (GetTimeMillis() - nHPSTimerStart > 4000)
                          {
                              dHashesPerSec = 1000.0 * nHashCounter / (GetTimeMillis() - nHPSTimerStart);
                              nHPSTimerStart = GetTimeMillis();
                              nHashCounter = 0;
                              static int64_t nLogTime;
                              if (GetTime() - nLogTime > 30 * 60)
                              {
                                  nLogTime = GetTime();
                                  LogPrintf("hashmeter %6.0f khash/s\n", dHashesPerSec/1000.0);
                              }
                          }
                      }
                  }
  
                  // Check for stop or if block needs to be rebuilt
                  boost::this_thread::interruption_point();
                  // Regtest mode doesn't require peers
                  if (vNodes.empty() && Params().MiningRequiresPeers())
                      break;
                  if (pblock->nNonce >= 0xffff0000)
                      break;
                  if (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - nStart > 60)
                      break;
                  if (pindexPrev != chainActive.Tip())
                      break;
  
                  // Update nTime every few seconds
                  UpdateTime(pblock, pindexPrev);
                  if (Params().AllowMinDifficultyBlocks())
                  {
                      // Changing pblock->nTime can change work required on testnet:
                      hashTarget.SetCompact(pblock->nBits);
                  }
              }
          }
      }
      catch (boost::thread_interrupted)
      {
          LogPrintf("TalismanMiner terminated\n");
          throw;
      }
      catch (const std::runtime_error &e)
      {
          LogPrintf("BitcoinMiner runtime error: %s\n", e.what());
          return;
      }
  }
  
  void GenerateBitcoins(bool fGenerate, CWallet* pwallet, int nThreads)
  {
      static boost::thread_group* minerThreads = NULL;
  
      if (nThreads < 0) {
          // In regtest threads defaults to 1
          if (Params().DefaultMinerThreads())
              nThreads = Params().DefaultMinerThreads();
          else
              nThreads = boost::thread::hardware_concurrency();
      }
  
      if (minerThreads != NULL)
      {
          minerThreads->interrupt_all();
          delete minerThreads;
          minerThreads = NULL;
      }
  
      if (nThreads == 0 || !fGenerate)
          return;
  
      minerThreads = new boost::thread_group();
      for (int i = 0; i < nThreads; i++)
          minerThreads->create_thread(boost::bind(&BitcoinMiner, pwallet));
  }
  
  #endif // ENABLE_WALLET
  