/* <!-- copyright */
/*
 * aria2 - The high speed download utility
 *
 * Copyright (C) 2006 Tatsuhiro Tsujikawa
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * In addition, as a special exception, the copyright holders give
 * permission to link the code of portions of this program with the
 * OpenSSL library under certain conditions as described in each
 * individual source file, and distribute linked combinations
 * including the two.
 * You must obey the GNU General Public License in all respects
 * for all of the code used other than OpenSSL.  If you modify
 * file(s) with this exception, you may extend this exception to your
 * version of the file(s), but you are not obligated to do so.  If you
 * do not wish to do so, delete this exception statement from your
 * version.  If you delete this exception statement from all source
 * files in the program, then also delete it here.
 */
/* copyright --> */
#ifndef _D_DOWNLOAD_ENGINE_H_
#define _D_DOWNLOAD_ENGINE_H_

#include "common.h"
#include "SharedHandle.h"
#include "Command.h"
#include "a2netcompat.h"
#include <deque>
#include <map>

namespace aria2 {

class Logger;
class Option;
#ifdef ENABLE_ASYNC_DNS
class AsyncNameResolver;
#endif // ENABLE_ASYNC_DNS
class RequestGroupMan;
class FileAllocationMan;
class StatCalc;
class CheckIntegrityMan;
class SocketCore;

class SocketEntry {
public:
  enum TYPE {
    TYPE_RD,
    TYPE_WR,
  };

  SharedHandle<SocketCore> socket;
  Command* command;
  TYPE type;
public:
  SocketEntry(const SharedHandle<SocketCore>& socket,
	      Command* command,
	      TYPE type);

  bool operator==(const SocketEntry& entry);
};

typedef std::deque<SocketEntry> SocketEntries;

#ifdef ENABLE_ASYNC_DNS
class AsyncNameResolverEntry {
public:
  SharedHandle<AsyncNameResolver> nameResolver;
  Command* command;
public:
  AsyncNameResolverEntry(const SharedHandle<AsyncNameResolver>& nameResolver,
			 Command* command);

  bool operator==(const AsyncNameResolverEntry& entry);
};

typedef std::deque<AsyncNameResolverEntry> AsyncNameResolverEntries;
#endif // ENABLE_ASYNC_DNS

class DownloadEngine {
private:
  void waitData();
  SocketEntries socketEntries;
#ifdef ENABLE_ASYNC_DNS
  AsyncNameResolverEntries nameResolverEntries;
#endif // ENABLE_ASYNC_DNS
  fd_set rfdset;
  fd_set wfdset;
  int fdmax;

  Logger* logger;
  
  SharedHandle<StatCalc> _statCalc;

  bool _haltRequested;

  // key = IP address:port, value = Socket
  std::multimap<std::string, SharedHandle<SocketCore> > _socketPool;
 
  void shortSleep() const;
  bool addSocket(const SocketEntry& socketEntry);
  bool deleteSocket(const SocketEntry& socketEntry);

  /**
   * Delegates to StatCalc
   */
  void calculateStatistics();

  void onEndOfRun();

  void afterEachIteration();

private:
  bool _noWait;

  std::deque<Command*> _routineCommands;

public:
  std::deque<Command*> commands;
  SharedHandle<RequestGroupMan> _requestGroupMan;
  SharedHandle<FileAllocationMan> _fileAllocationMan;
  SharedHandle<CheckIntegrityMan> _checkIntegrityMan;
  const Option* option;
  
  DownloadEngine();

  virtual ~DownloadEngine();

  void run();

  void cleanQueue();

  void updateFdSet();

  bool addSocketForReadCheck(const SharedHandle<SocketCore>& socket,
			     Command* command);
  bool deleteSocketForReadCheck(const SharedHandle<SocketCore>& socket,
				Command* command);
  bool addSocketForWriteCheck(const SharedHandle<SocketCore>& socket,
			      Command* command);
  bool deleteSocketForWriteCheck(const SharedHandle<SocketCore>& socket,
				 Command* command);
#ifdef ENABLE_ASYNC_DNS
  bool addNameResolverCheck(const SharedHandle<AsyncNameResolver>& resolver,
			    Command* command);
  bool deleteNameResolverCheck(const SharedHandle<AsyncNameResolver>& resolver,
			       Command* command);
#endif // ENABLE_ASYNC_DNS

  void addCommand(const Commands& commands);

  void fillCommand();

  void setStatCalc(const SharedHandle<StatCalc>& statCalc);

  bool isHaltRequested() const
  {
    return _haltRequested;
  }

  void requestHalt();

  void setNoWait(bool b);

  void addRoutineCommand(Command* command);

  void poolSocket(const std::string& ipaddr, uint16_t port,
		  const SharedHandle<SocketCore>& sock);

  SharedHandle<SocketCore> popPooledSocket(const std::string& ipaddr,
					   uint16_t port);


  SharedHandle<SocketCore>
  popPooledSocket(const std::deque<std::string>& ipaddrs, uint16_t port);
};

typedef SharedHandle<DownloadEngine> DownloadEngineHandle;

} // namespace aria2

#endif // _D_DOWNLOAD_ENGINE_H_