text: // Copyright (c) 2009-2010 Satoshi Nakamoto
  // Copyright (c) 2009-2014 The Bitcoin Core developers
  // Distributed under the MIT software license, see the accompanying
  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
  
  #include "primitives/block.h"
  #include "primitives/transaction.h"
  #include "main.h"
  #include "rpcserver.h"
  #include "streams.h"
  #include "sync.h"
  #include "txmempool.h"
  #include "utilstrencodings.h"
  #include "version.h"
  
  #include <boost/algorithm/string.hpp>
  #include <boost/dynamic_bitset.hpp>
  
  using namespace std;
  using namespace json_spirit;
  
  static const int MAX_GETUTXOS_OUTPOINTS = 15; //allow a max of 15 outpoints to be queried at once
  
  enum RetFormat {
      RF_UNDEF,
      RF_BINARY,
      RF_HEX,
      RF_JSON,
  };
  
  static const struct {
      enum RetFormat rf;
      const char* name;
  } rf_names[] = {
        {RF_UNDEF, ""},
        {RF_BINARY, "bin"},
        {RF_HEX, "hex"},
        {RF_JSON, "json"},
  };
  
  struct CCoin {
      uint32_t nTxVer; // Don't call this nVersion, that name has a special meaning inside IMPLEMENT_SERIALIZE
      uint32_t nHeight;
      CTxOut out;
  
      ADD_SERIALIZE_METHODS;
  
      template <typename Stream, typename Operation>
      inline void SerializationOp(Stream& s, Operation ser_action, int nType, int nVersion)
      {
          READWRITE(nTxVer);
          READWRITE(nHeight);
          READWRITE(out);
      }
  };
  
  class RestErr
  {
  public:
      enum HTTPStatusCode status;
      string message;
  };
  
  extern void TxToJSON(const CTransaction& tx, const uint256 hashBlock, Object& entry);
  extern Object blockToJSON(const CBlock& block, const CBlockIndex* blockindex, bool txDetails = false);
  extern void ScriptPubKeyToJSON(const CScript& scriptPubKey, Object& out, bool fIncludeHex);
  
  static RestErr RESTERR(enum HTTPStatusCode status, string message)
  {
      RestErr re;
      re.status = status;
      re.message = message;
      return re;
  }
  
  static enum RetFormat ParseDataFormat(vector<string>& params, const string strReq)
  {
      boost::split(params, strReq, boost::is_any_of("."));
      if (params.size() > 1) {
          for (unsigned int i = 0; i < ARRAYLEN(rf_names); i++)
              if (params[1] == rf_names[i].name)
                  return rf_names[i].rf;
      }
  
      return rf_names[0].rf;
  }
  
  static string AvailableDataFormatsString()
  {
      string formats = "";
      for (unsigned int i = 0; i < ARRAYLEN(rf_names); i++)
          if (strlen(rf_names[i].name) > 0) {
              formats.append(".");
              formats.append(rf_names[i].name);
              formats.append(", ");
          }
  
      if (formats.length() > 0)
          return formats.substr(0, formats.length() - 2);
  
      return formats;
  }
  
  static bool ParseHashStr(const string& strReq, uint256& v)
  {
      if (!IsHex(strReq) || (strReq.size() != 64))
          return false;
  
      v.SetHex(strReq);
      return true;
  }
  
  static bool rest_headers(AcceptedConnection* conn,
                           const std::string& strURIPart,
                           const std::string& strRequest,
                           const std::map<std::string, std::string>& mapHeaders,
                           bool fRun)
  {
      vector<string> params;
      const RetFormat rf = ParseDataFormat(params, strURIPart);
      vector<string> path;
      boost::split(path, params[0], boost::is_any_of("/"));
  
      if (path.size() != 2)
          throw RESTERR(HTTP_BAD_REQUEST, "No header count specified. Use /rest/headers/<count>/<hash>.<ext>.");
  
      long count = strtol(path[0].c_str(), NULL, 10);
      if (count < 1 || count > 2000)
          throw RESTERR(HTTP_BAD_REQUEST, "Header count out of range: " + path[0]);
  
      string hashStr = path[1];
      uint256 hash;
      if (!ParseHashStr(hashStr, hash))
          throw RESTERR(HTTP_BAD_REQUEST, "Invalid hash: " + hashStr);
  
      std::vector<CBlockHeader> headers;
      headers.reserve(count);
      {
          LOCK(cs_main);
          BlockMap::const_iterator it = mapBlockIndex.find(hash);
          const CBlockIndex *pindex = (it != mapBlockIndex.end()) ? it->second : NULL;
          while (pindex != NULL && chainActive.Contains(pindex)) {
              headers.push_back(pindex->GetBlockHeader());
              if (headers.size() == (unsigned long)count)
                  break;
              pindex = chainActive.Next(pindex);
          }
      }
  
      CDataStream ssHeader(SER_NETWORK, PROTOCOL_VERSION);
      BOOST_FOREACH(const CBlockHeader &header, headers) {
          ssHeader << header;
      }
  
      switch (rf) {
      case RF_BINARY: {
          string binaryHeader = ssHeader.str();
          conn->stream() << HTTPReplyHeader(HTTP_OK, fRun, binaryHeader.size(), "application/octet-stream") << binaryHeader << std::flush;
          return true;
      }
  
      case RF_HEX: {
          string strHex = HexStr(ssHeader.begin(), ssHeader.end()) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strHex, fRun, false, "text/plain") << std::flush;
          return true;
      }
  
      default: {
          throw RESTERR(HTTP_NOT_FOUND, "output format not found (available: .bin, .hex)");
      }
      }
  
      // not reached
      return true; // continue to process further HTTP reqs on this cxn
  }
  
  static bool rest_block(AcceptedConnection* conn,
                         const std::string& strURIPart,
                         const std::string& strRequest,
                         const std::map<std::string, std::string>& mapHeaders,
                         bool fRun,
                         bool showTxDetails)
  {
      vector<string> params;
      const RetFormat rf = ParseDataFormat(params, strURIPart);
  
      string hashStr = params[0];
      uint256 hash;
      if (!ParseHashStr(hashStr, hash))
          throw RESTERR(HTTP_BAD_REQUEST, "Invalid hash: " + hashStr);
  
      CBlock block;
      CBlockIndex* pblockindex = NULL;
      {
          LOCK(cs_main);
          if (mapBlockIndex.count(hash) == 0)
              throw RESTERR(HTTP_NOT_FOUND, hashStr + " not found");
  
          pblockindex = mapBlockIndex[hash];
          if (fHavePruned && !(pblockindex->nStatus & BLOCK_HAVE_DATA) && pblockindex->nTx > 0)
              throw RESTERR(HTTP_NOT_FOUND, hashStr + " not available (pruned data)");
  
          if (!ReadBlockFromDisk(block, pblockindex))
              throw RESTERR(HTTP_NOT_FOUND, hashStr + " not found");
      }
  
      CDataStream ssBlock(SER_NETWORK, PROTOCOL_VERSION);
      ssBlock << block;
  
      switch (rf) {
      case RF_BINARY: {
          string binaryBlock = ssBlock.str();
          conn->stream() << HTTPReplyHeader(HTTP_OK, fRun, binaryBlock.size(), "application/octet-stream") << binaryBlock << std::flush;
          return true;
      }
  
      case RF_HEX: {
          string strHex = HexStr(ssBlock.begin(), ssBlock.end()) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strHex, fRun, false, "text/plain") << std::flush;
          return true;
      }
  
      case RF_JSON: {
          Object objBlock = blockToJSON(block, pblockindex, showTxDetails);
          string strJSON = write_string(Value(objBlock), false) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strJSON, fRun) << std::flush;
          return true;
      }
  
      default: {
          throw RESTERR(HTTP_NOT_FOUND, "output format not found (available: " + AvailableDataFormatsString() + ")");
      }
      }
  
      // not reached
      return true; // continue to process further HTTP reqs on this cxn
  }
  
  static bool rest_block_extended(AcceptedConnection* conn,
                         const std::string& strURIPart,
                         const std::string& strRequest,
                         const std::map<std::string, std::string>& mapHeaders,
                         bool fRun)
  {
      return rest_block(conn, strURIPart, strRequest, mapHeaders, fRun, true);
  }
  
  static bool rest_block_notxdetails(AcceptedConnection* conn,
                         const std::string& strURIPart,
                         const std::string& strRequest,
                         const std::map<std::string, std::string>& mapHeaders,
                         bool fRun)
  {
      return rest_block(conn, strURIPart, strRequest, mapHeaders, fRun, false);
  }
  
  static bool rest_chaininfo(AcceptedConnection* conn,
                             const std::string& strURIPart,
                             const std::string& strRequest,
                             const std::map<std::string, std::string>& mapHeaders,
                             bool fRun)
  {
      vector<string> params;
      const RetFormat rf = ParseDataFormat(params, strURIPart);
  
      switch (rf) {
      case RF_JSON: {
          Array rpcParams;
          Value chainInfoObject = getblockchaininfo(rpcParams, false);
  
          string strJSON = write_string(chainInfoObject, false) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strJSON, fRun) << std::flush;
          return true;
      }
      default: {
          throw RESTERR(HTTP_NOT_FOUND, "output format not found (available: json)");
      }
      }
  
      // not reached
      return true; // continue to process further HTTP reqs on this cxn
  }
  
  static bool rest_tx(AcceptedConnection* conn,
                      const std::string& strURIPart,
                      const std::string& strRequest,
                      const std::map<std::string, std::string>& mapHeaders,
                      bool fRun)
  {
      vector<string> params;
      const RetFormat rf = ParseDataFormat(params, strURIPart);
  
      string hashStr = params[0];
      uint256 hash;
      if (!ParseHashStr(hashStr, hash))
          throw RESTERR(HTTP_BAD_REQUEST, "Invalid hash: " + hashStr);
  
      CTransaction tx;
      uint256 hashBlock = uint256();
      if (!GetTransaction(hash, tx, hashBlock, true))
          throw RESTERR(HTTP_NOT_FOUND, hashStr + " not found");
  
      CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
      ssTx << tx;
  
      switch (rf) {
      case RF_BINARY: {
          string binaryTx = ssTx.str();
          conn->stream() << HTTPReplyHeader(HTTP_OK, fRun, binaryTx.size(), "application/octet-stream") << binaryTx << std::flush;
          return true;
      }
  
      case RF_HEX: {
          string strHex = HexStr(ssTx.begin(), ssTx.end()) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strHex, fRun, false, "text/plain") << std::flush;
          return true;
      }
  
      case RF_JSON: {
          Object objTx;
          TxToJSON(tx, hashBlock, objTx);
          string strJSON = write_string(Value(objTx), false) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strJSON, fRun) << std::flush;
          return true;
      }
  
      default: {
          throw RESTERR(HTTP_NOT_FOUND, "output format not found (available: " + AvailableDataFormatsString() + ")");
      }
      }
  
      // not reached
      return true; // continue to process further HTTP reqs on this cxn
  }
  
  static bool rest_getutxos(AcceptedConnection* conn,
                            const std::string& strURIPart,
                            const std::string& strRequest,
                            const std::map<std::string, std::string>& mapHeaders,
                            bool fRun)
  {
      vector<string> params;
      enum RetFormat rf = ParseDataFormat(params, strURIPart);
  
      vector<string> uriParts;
      if (params.size() > 0 && params[0].length() > 1)
      {
          std::string strUriParams = params[0].substr(1);
          boost::split(uriParts, strUriParams, boost::is_any_of("/"));
      }
  
      // throw exception in case of a empty request
      if (strRequest.length() == 0 && uriParts.size() == 0)
          throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, "Error: empty request");
  
      bool fInputParsed = false;
      bool fCheckMemPool = false;
      vector<COutPoint> vOutPoints;
  
      // parse/deserialize input
      // input-format = output-format, rest/getutxos/bin requires binary input, gives binary output, ...
  
      if (uriParts.size() > 0)
      {
  
          //inputs is sent over URI scheme (/rest/getutxos/checkmempool/txid1-n/txid2-n/...)
          if (uriParts.size() > 0 && uriParts[0] == "checkmempool")
              fCheckMemPool = true;
  
          for (size_t i = (fCheckMemPool) ? 1 : 0; i < uriParts.size(); i++)
          {
              uint256 txid;
              int32_t nOutput;
              std::string strTxid = uriParts[i].substr(0, uriParts[i].find("-"));
              std::string strOutput = uriParts[i].substr(uriParts[i].find("-")+1);
  
              if (!ParseInt32(strOutput, &nOutput) || !IsHex(strTxid))
                  throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, "Parse error");
  
              txid.SetHex(strTxid);
              vOutPoints.push_back(COutPoint(txid, (uint32_t)nOutput));
          }
  
          if (vOutPoints.size() > 0)
              fInputParsed = true;
          else
              throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, "Error: empty request");
      }
  
      string strRequestMutable = strRequest; //convert const string to string for allowing hex to bin converting
  
      switch (rf) {
      case RF_HEX: {
          // convert hex to bin, continue then with bin part
          std::vector<unsigned char> strRequestV = ParseHex(strRequest);
          strRequestMutable.assign(strRequestV.begin(), strRequestV.end());
      }
  
      case RF_BINARY: {
          try {
              //deserialize only if user sent a request
              if (strRequestMutable.size() > 0)
              {
                  if (fInputParsed) //don't allow sending input over URI and HTTP RAW DATA
                      throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, "Combination of URI scheme inputs and raw post data is not allowed");
  
                  CDataStream oss(SER_NETWORK, PROTOCOL_VERSION);
                  oss << strRequestMutable;
                  oss >> fCheckMemPool;
                  oss >> vOutPoints;
              }
          } catch (const std::ios_base::failure& e) {
              // abort in case of unreadable binary data
              throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, "Parse error");
          }
          break;
      }
  
      case RF_JSON: {
          if (!fInputParsed)
              throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, "Error: empty request");
          break;
      }
      default: {
          throw RESTERR(HTTP_NOT_FOUND, "output format not found (available: " + AvailableDataFormatsString() + ")");
      }
      }
  
      // limit max outpoints
      if (vOutPoints.size() > MAX_GETUTXOS_OUTPOINTS)
          throw RESTERR(HTTP_INTERNAL_SERVER_ERROR, strprintf("Error: max outpoints exceeded (max: %d, tried: %d)", MAX_GETUTXOS_OUTPOINTS, vOutPoints.size()));
  
      // check spentness and form a bitmap (as well as a JSON capable human-readble string representation)
      vector<unsigned char> bitmap;
      vector<CCoin> outs;
      std::string bitmapStringRepresentation;
      boost::dynamic_bitset<unsigned char> hits(vOutPoints.size());
      {
          LOCK2(cs_main, mempool.cs);
  
          CCoinsView viewDummy;
          CCoinsViewCache view(&viewDummy);
  
          CCoinsViewCache& viewChain = *pcoinsTip;
          CCoinsViewMemPool viewMempool(&viewChain, mempool);
  
          if (fCheckMemPool)
              view.SetBackend(viewMempool); // switch cache backend to db+mempool in case user likes to query mempool
  
          for (size_t i = 0; i < vOutPoints.size(); i++) {
              CCoins coins;
              uint256 hash = vOutPoints[i].hash;
              if (view.GetCoins(hash, coins)) {
                  mempool.pruneSpent(hash, coins);
                  if (coins.IsAvailable(vOutPoints[i].n)) {
                      hits[i] = true;
                      // Safe to index into vout here because IsAvailable checked if it's off the end of the array, or if
                      // n is valid but points to an already spent output (IsNull).
                      CCoin coin;
                      coin.nTxVer = coins.nVersion;
                      coin.nHeight = coins.nHeight;
                      coin.out = coins.vout.at(vOutPoints[i].n);
                      assert(!coin.out.IsNull());
                      outs.push_back(coin);
                  }
              }
  
              bitmapStringRepresentation.append(hits[i] ? "1" : "0"); // form a binary string representation (human-readable for json output)
          }
      }
      boost::to_block_range(hits, std::back_inserter(bitmap));
  
      switch (rf) {
      case RF_BINARY: {
          // serialize data
          // use exact same output as mentioned in Bip64
          CDataStream ssGetUTXOResponse(SER_NETWORK, PROTOCOL_VERSION);
          ssGetUTXOResponse << chainActive.Height() << chainActive.Tip()->GetBlockHash() << bitmap << outs;
          string ssGetUTXOResponseString = ssGetUTXOResponse.str();
  
          conn->stream() << HTTPReplyHeader(HTTP_OK, fRun, ssGetUTXOResponseString.size(), "application/octet-stream") << ssGetUTXOResponseString << std::flush;
          return true;
      }
  
      case RF_HEX: {
          CDataStream ssGetUTXOResponse(SER_NETWORK, PROTOCOL_VERSION);
          ssGetUTXOResponse << chainActive.Height() << chainActive.Tip()->GetBlockHash() << bitmap << outs;
          string strHex = HexStr(ssGetUTXOResponse.begin(), ssGetUTXOResponse.end()) + "\n";
  
          conn->stream() << HTTPReply(HTTP_OK, strHex, fRun, false, "text/plain") << std::flush;
          return true;
      }
  
      case RF_JSON: {
          Object objGetUTXOResponse;
  
          // pack in some essentials
          // use more or less the same output as mentioned in Bip64
          objGetUTXOResponse.push_back(Pair("chainHeight", chainActive.Height()));
          objGetUTXOResponse.push_back(Pair("chaintipHash", chainActive.Tip()->GetBlockHash().GetHex()));
          objGetUTXOResponse.push_back(Pair("bitmap", bitmapStringRepresentation));
  
          Array utxos;
          BOOST_FOREACH (const CCoin& coin, outs) {
              Object utxo;
              utxo.push_back(Pair("txvers", (int32_t)coin.nTxVer));
              utxo.push_back(Pair("height", (int32_t)coin.nHeight));
              utxo.push_back(Pair("value", ValueFromAmount(coin.out.nValue)));
              //utxo.push_back(Pair("interest", ValueFromAmount(komodo_interest(coin.out.nValue,coin.nLockTime,chainActive.Tip()->nTime))));
  
              // include the script in a json output
              Object o;
              ScriptPubKeyToJSON(coin.out.scriptPubKey, o, true);
              utxo.push_back(Pair("scriptPubKey", o));
              utxos.push_back(utxo);
          }
          objGetUTXOResponse.push_back(Pair("utxos", utxos));
  
          // return json string
          string strJSON = write_string(Value(objGetUTXOResponse), false) + "\n";
          conn->stream() << HTTPReply(HTTP_OK, strJSON, fRun) << std::flush;
          return true;
      }
      default: {
          throw RESTERR(HTTP_NOT_FOUND, "output format not found (available: " + AvailableDataFormatsString() + ")");
      }
      }
  
      // not reached
      return true; // continue to process further HTTP reqs on this cxn
  }
  
  static const struct {
      const char* prefix;
      bool (*handler)(AcceptedConnection* conn,
                      const std::string& strURIPart,
                      const std::string& strRequest,
                      const std::map<std::string, std::string>& mapHeaders,
                      bool fRun);
  } uri_prefixes[] = {
        {"/rest/tx/", rest_tx},
        {"/rest/block/notxdetails/", rest_block_notxdetails},
        {"/rest/block/", rest_block_extended},
        {"/rest/chaininfo", rest_chaininfo},
        {"/rest/headers/", rest_headers},
        {"/rest/getutxos", rest_getutxos},
  };
  
  bool HTTPReq_REST(AcceptedConnection* conn,
                    const std::string& strURI,
                    const string& strRequest,
                    const std::map<std::string, std::string>& mapHeaders,
                    bool fRun)
  {
      try {
          std::string statusmessage;
          if (RPCIsInWarmup(&statusmessage))
              throw RESTERR(HTTP_SERVICE_UNAVAILABLE, "Service temporarily unavailable: " + statusmessage);
  
          for (unsigned int i = 0; i < ARRAYLEN(uri_prefixes); i++) {
              unsigned int plen = strlen(uri_prefixes[i].prefix);
              if (strURI.substr(0, plen) == uri_prefixes[i].prefix) {
                  string strURIPart = strURI.substr(plen);
                  return uri_prefixes[i].handler(conn, strURIPart, strRequest, mapHeaders, fRun);
              }
          }
      } catch (const RestErr& re) {
          conn->stream() << HTTPReply(re.status, re.message + "\r\n", false, false, "text/plain") << std::flush;
          return false;
      }
  
      conn->stream() << HTTPError(HTTP_NOT_FOUND, false) << std::flush;
      return false;
  }
  