/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
#ifndef _THRIFT_TCONCURRENTCLIENTSYNCINFO_H_
#define _THRIFT_TCONCURRENTCLIENTSYNCINFO_H_ 1

#include <thrift/protocol/TProtocol.h>
#include <thrift/concurrency/Mutex.h>
#include <thrift/concurrency/Monitor.h>
#include <boost/shared_ptr.hpp>
#include <vector>
#include <string>
#include <map>

namespace apache { namespace thrift { namespace async {

class TConcurrentClientSyncInfo;

class TConcurrentSendSentry
{
public:
  explicit TConcurrentSendSentry(TConcurrentClientSyncInfo *sync);
  ~TConcurrentSendSentry();

  void commit();
private:
  TConcurrentClientSyncInfo &sync_;
  bool committed_;
};

class TConcurrentRecvSentry
{
public:
  TConcurrentRecvSentry(TConcurrentClientSyncInfo *sync, int32_t seqid);
  ~TConcurrentRecvSentry();

  void commit();
private:
  TConcurrentClientSyncInfo &sync_;
  int32_t seqid_;
  bool committed_;
};

class TConcurrentClientSyncInfo
{
private: //typedefs
  typedef boost::shared_ptr< ::apache::thrift::concurrency::Monitor> MonitorPtr;
  typedef std::map<int32_t, MonitorPtr> MonitorMap;
public:
  TConcurrentClientSyncInfo();

  int32_t generateSeqId();

  bool getPending(
    std::string &fname,
    ::apache::thrift::protocol::TMessageType &mtype,
    int32_t &rseqid); /* requires readMutex_ */

  void updatePending(
    const std::string &fname,
    ::apache::thrift::protocol::TMessageType mtype,
    int32_t rseqid); /* requires readMutex_ */

  void waitForWork(int32_t seqid); /* requires readMutex_ */

  ::apache::thrift::concurrency::Mutex &getReadMutex() {return readMutex_;}
  ::apache::thrift::concurrency::Mutex &getWriteMutex() {return writeMutex_;}

private: //constants
  enum {MONITOR_CACHE_SIZE = 10};
private: //functions
  MonitorPtr newMonitor_(
    const ::apache::thrift::concurrency::Guard &seqidGuard); /* requires seqidMutex_ */
  void deleteMonitor_(
    const ::apache::thrift::concurrency::Guard &seqidGuard,
    MonitorPtr &m); /*noexcept*/ /* requires seqidMutex_ */
  void wakeupAnyone_(
    const ::apache::thrift::concurrency::Guard &seqidGuard); /* requires seqidMutex_ */
  void markBad_(
    const ::apache::thrift::concurrency::Guard &seqidGuard); /* requires seqidMutex_ */
  void throwBadSeqId_();
  void throwDeadConnection_();
private: //data members

  volatile bool stop_;

  ::apache::thrift::concurrency::Mutex seqidMutex_;
  // begin seqidMutex_ protected members
  int32_t nextseqid_;
  MonitorMap seqidToMonitorMap_;
  std::vector<MonitorPtr> freeMonitors_;
  // end seqidMutex_ protected members

  ::apache::thrift::concurrency::Mutex writeMutex_;

  ::apache::thrift::concurrency::Mutex readMutex_;
  // begin readMutex_ protected members
  bool recvPending_;
  bool wakeupSomeone_;
  int32_t seqidPending_;
  std::string fnamePending_;
  ::apache::thrift::protocol::TMessageType mtypePending_;
  // end readMutex_ protected members


  friend class TConcurrentSendSentry;
  friend class TConcurrentRecvSentry;
};

}}} // apache::thrift::async

#endif // _THRIFT_TCONCURRENTCLIENTSYNCINFO_H_
