text: //------------------------------------------------------------------------------
  /*
      This file is part of rippled: https://github.com/ripple/rippled
      Copyright (c) 2012, 2013 Ripple Labs Inc.
  
      Permission to use, copy, modify, and/or distribute this software for any
      purpose  with  or without fee is hereby granted, provided that the above
      copyright notice and this permission notice appear in all copies.
  
      THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
      WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
      MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
      ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
      WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
      ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
      OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  */
  //==============================================================================
  
  #include <BeastConfig.h>
  #include <ripple/basics/contract.h>
  #include <ripple/basics/Log.h>
  #include <ripple/json/to_string.h>
  #include <ripple/protocol/Indexes.h>
  #include <ripple/protocol/JsonFields.h>
  #include <ripple/protocol/STLedgerEntry.h>
  #include <boost/format.hpp>
  
  namespace ripple {
  
  STLedgerEntry::STLedgerEntry (Keylet const& k)
      :  STObject(sfLedgerEntry)
      , key_ (k.key)
      , type_ (k.type)
      , mMutable (true)
  {
      mFormat =
          LedgerFormats::getInstance().findByType (type_);
      if (mFormat == nullptr)
          Throw<std::runtime_error> ("invalid ledger entry type");
      set (mFormat->elements);
      setFieldU16 (sfLedgerEntryType,
          static_cast <std::uint16_t> (mFormat->getType ()));
  }
  
  STLedgerEntry::STLedgerEntry (
      SerialIter& sit, uint256 const& index)
      : STObject (sfLedgerEntry), key_ (index), mMutable (true)
  {
      set (sit);
      setSLEType ();
  }
  
  STLedgerEntry::STLedgerEntry (
      const Serializer& s, uint256 const& index)
      : STObject (sfLedgerEntry), key_ (index), mMutable (true)
  {
      SerialIter sit (s.slice());
      set (sit);
      setSLEType ();
  }
  
  STLedgerEntry::STLedgerEntry (
      const STObject & object, uint256 const& index)
      : STObject (object), key_(index),  mMutable (true)
  {
      setSLEType ();
  }
  
  void STLedgerEntry::setSLEType ()
  {
      mFormat = LedgerFormats::getInstance().findByType (
          static_cast <LedgerEntryType> (getFieldU16 (sfLedgerEntryType)));
  
      if (mFormat == nullptr)
          Throw<std::runtime_error> ("invalid ledger entry type");
  
      type_ = mFormat->getType ();
      if (!setType (mFormat->elements))
      {
          if (auto j = debugJournal().warn())
          {
              j << "Ledger entry not valid for type " << mFormat->getName ();
              j << "Object: " << getJson (0);
          }
  
          Throw<std::runtime_error> ("ledger entry not valid for type");
      }
  }
  
  std::string STLedgerEntry::getFullText () const
  {
      std::string ret = "\"";
      ret += to_string (key_);
      ret += "\" = { ";
      ret += mFormat->getName ();
      ret += ", ";
      ret += STObject::getFullText ();
      ret += "}";
      return ret;
  }
  
  std::string STLedgerEntry::getText () const
  {
      return str (boost::format ("{ %s, %s }")
                  % to_string (key_)
                  % STObject::getText ());
  }
  
  Json::Value STLedgerEntry::getJson (int options) const
  {
      Json::Value ret (STObject::getJson (options));
  
      ret[jss::index] = to_string (key_);
  
      return ret;
  }
  
  bool STLedgerEntry::isThreadedType () const
  {
      return getFieldIndex (sfPreviousTxnID) != -1;
  }
  
  bool STLedgerEntry::isThreaded () const
  {
      return isFieldPresent (sfPreviousTxnID);
  }
  
  uint256 STLedgerEntry::getThreadedTransaction () const
  {
      return getFieldH256 (sfPreviousTxnID);
  }
  
  std::uint32_t STLedgerEntry::getThreadedLedger () const
  {
      return getFieldU32 (sfPreviousTxnLgrSeq);
  }
  
  bool STLedgerEntry::thread (uint256 const& txID, std::uint32_t ledgerSeq,
                                      uint256& prevTxID, std::uint32_t& prevLedgerID)
  {
      uint256 oldPrevTxID = getFieldH256 (sfPreviousTxnID);
  
      JLOG (debugJournal().trace())
          << "Thread Tx:" << txID << " prev:" << oldPrevTxID;
  
      if (oldPrevTxID == txID)
      {
          // this transaction is already threaded
          assert (getFieldU32 (sfPreviousTxnLgrSeq) == ledgerSeq);
          return false;
      }
  
      prevTxID = oldPrevTxID;
      prevLedgerID = getFieldU32 (sfPreviousTxnLgrSeq);
      setFieldH256 (sfPreviousTxnID, txID);
      setFieldU32 (sfPreviousTxnLgrSeq, ledgerSeq);
      return true;
  }
  
  } // ripple
  