/* <!-- 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 --> */
#include "PeerInteractionCommand.h"

#include <algorithm>

#include "DownloadEngine.h"
#include "PeerInitiateConnectionCommand.h"
#include "DefaultBtInteractive.h"
#include "DlAbortEx.h"
#include "message.h"
#include "prefs.h"
#include "SocketCore.h"
#include "Option.h"
#include "DownloadContext.h"
#include "Peer.h"
#include "BtMessage.h"
#include "BtRuntime.h"
#include "PeerStorage.h"
#include "DefaultBtMessageDispatcher.h"
#include "DefaultBtMessageReceiver.h"
#include "DefaultBtRequestFactory.h"
#include "DefaultBtMessageFactory.h"
#include "DefaultBtInteractive.h"
#include "PeerConnection.h"
#include "ExtensionMessageFactory.h"
#include "DHTRoutingTable.h"
#include "DHTTaskQueue.h"
#include "DHTTaskFactory.h"
#include "DHTNode.h"
#include "DHTRegistry.h"
#include "DHTPeerAnnounceStorage.h"
#include "DHTTokenTracker.h"
#include "DHTMessageDispatcher.h"
#include "DHTMessageReceiver.h"
#include "DHTMessageFactory.h"
#include "DHTMessageCallback.h"
#include "PieceStorage.h"
#include "RequestGroup.h"
#include "DefaultExtensionMessageFactory.h"
#include "RequestGroupMan.h"
#include "ExtensionMessageRegistry.h"
#include "bittorrent_helper.h"
#include "UTMetadataRequestFactory.h"
#include "UTMetadataRequestTracker.h"
#include "BtRegistry.h"

namespace aria2 {

PeerInteractionCommand::PeerInteractionCommand
(cuid_t cuid,
 RequestGroup* requestGroup,
 const SharedHandle<Peer>& p,
 DownloadEngine* e,
 const SharedHandle<BtRuntime>& btRuntime,
 const SharedHandle<PieceStorage>& pieceStorage,
 const SharedHandle<PeerStorage>& peerStorage,
 const SharedHandle<SocketCore>& s,
 Seq sequence,
 const SharedHandle<PeerConnection>& passedPeerConnection)
  :PeerAbstractCommand(cuid, p, e, s),
   requestGroup_(requestGroup),
   btRuntime_(btRuntime),
   pieceStorage_(pieceStorage),
   peerStorage_(peerStorage),
   sequence_(sequence)
{
  // TODO move following bunch of processing to separate method, like init()
  if(sequence_ == INITIATOR_SEND_HANDSHAKE) {
    disableReadCheckSocket();
    setWriteCheckSocket(getSocket());
    setTimeout(getOption()->getAsInt(PREF_PEER_CONNECTION_TIMEOUT));
  }

  int family;
  unsigned char compact[COMPACT_LEN_IPV6];
  int compactlen = bittorrent::packcompact
    (compact, getPeer()->getIPAddress(), getPeer()->getPort());
  if(compactlen == COMPACT_LEN_IPV6) {
    family = AF_INET6;
  } else {
    family = AF_INET;
  }

  SharedHandle<TorrentAttribute> torrentAttrs =
    bittorrent::getTorrentAttrs(requestGroup_->getDownloadContext());
  bool metadataGetMode = torrentAttrs->metadata.empty();

  SharedHandle<ExtensionMessageRegistry> exMsgRegistry
    (new ExtensionMessageRegistry());
  exMsgRegistry->setExtensionMessageID(ExtensionMessageRegistry::UT_PEX, 8);
  // http://www.bittorrent.org/beps/bep_0009.html
  exMsgRegistry->setExtensionMessageID(ExtensionMessageRegistry::UT_METADATA,
                                       9);

  SharedHandle<UTMetadataRequestFactory> utMetadataRequestFactory;
  SharedHandle<UTMetadataRequestTracker> utMetadataRequestTracker;
  if(metadataGetMode) {
    utMetadataRequestFactory.reset(new UTMetadataRequestFactory());
    utMetadataRequestTracker.reset(new UTMetadataRequestTracker());
  }

  DefaultExtensionMessageFactory* extensionMessageFactoryPtr
    (new DefaultExtensionMessageFactory(getPeer(), exMsgRegistry));
  extensionMessageFactoryPtr->setPeerStorage(peerStorage);
  extensionMessageFactoryPtr->setDownloadContext
    (requestGroup_->getDownloadContext());
  extensionMessageFactoryPtr->setUTMetadataRequestTracker
    (utMetadataRequestTracker.get());
  // PieceStorage will be set later.
  SharedHandle<ExtensionMessageFactory> extensionMessageFactory
    (extensionMessageFactoryPtr);



  DefaultBtMessageFactory* factoryPtr(new DefaultBtMessageFactory());
  factoryPtr->setCuid(cuid);
  factoryPtr->setDownloadContext(requestGroup_->getDownloadContext());
  factoryPtr->setPieceStorage(pieceStorage);
  factoryPtr->setPeerStorage(peerStorage);
  factoryPtr->setExtensionMessageFactory(extensionMessageFactory);
  factoryPtr->setPeer(getPeer());
  if(family == AF_INET) {
    factoryPtr->setLocalNode(DHTRegistry::getData().localNode.get());
    factoryPtr->setRoutingTable(DHTRegistry::getData().routingTable.get());
    factoryPtr->setTaskQueue(DHTRegistry::getData().taskQueue.get());
    factoryPtr->setTaskFactory(DHTRegistry::getData().taskFactory.get());
  } else {
    factoryPtr->setLocalNode(DHTRegistry::getData6().localNode.get());
    factoryPtr->setRoutingTable(DHTRegistry::getData6().routingTable.get());
    factoryPtr->setTaskQueue(DHTRegistry::getData6().taskQueue.get());
    factoryPtr->setTaskFactory(DHTRegistry::getData6().taskFactory.get());
  }
  if(metadataGetMode) {
    factoryPtr->enableMetadataGetMode();
  }
  SharedHandle<BtMessageFactory> factory(factoryPtr);


  SharedHandle<PeerConnection> peerConnection;
  if(!passedPeerConnection) {
    peerConnection.reset(new PeerConnection(cuid, getPeer(), getSocket()));
  } else {
    peerConnection = passedPeerConnection;
    if(sequence_ == RECEIVER_WAIT_HANDSHAKE &&
       peerConnection->getBufferLength() > 0) {
      setStatus(Command::STATUS_ONESHOT_REALTIME);
      getDownloadEngine()->setNoWait(true);
    }
  }
  // If the number of pieces gets bigger, the length of Bitfield
  // message payload exceeds the initial buffer capacity of
  // PeerConnection, which is MAX_PAYLOAD_LEN.  We expand buffer as
  // necessary so that PeerConnection can receive the Bitfield
  // message.
  size_t bitfieldPayloadSize =
    1+(requestGroup_->getDownloadContext()->getNumPieces()+7)/8;
  peerConnection->reserveBuffer(bitfieldPayloadSize);

  DefaultBtMessageDispatcher* dispatcherPtr(new DefaultBtMessageDispatcher());
  dispatcherPtr->setCuid(cuid);
  dispatcherPtr->setPeer(getPeer());
  dispatcherPtr->setDownloadContext(requestGroup_->getDownloadContext());
  dispatcherPtr->setPieceStorage(pieceStorage);
  dispatcherPtr->setPeerStorage(peerStorage);
  dispatcherPtr->setRequestTimeout(getOption()->
                                   getAsInt(PREF_BT_REQUEST_TIMEOUT));
  dispatcherPtr->setBtMessageFactory(factoryPtr);
  dispatcherPtr->setRequestGroupMan
    (getDownloadEngine()->getRequestGroupMan().get());
  SharedHandle<BtMessageDispatcher> dispatcher(dispatcherPtr);

  DefaultBtMessageReceiver* receiverPtr(new DefaultBtMessageReceiver());
  receiverPtr->setDownloadContext(requestGroup_->getDownloadContext());
  receiverPtr->setPeerConnection(peerConnection.get());
  receiverPtr->setDispatcher(dispatcherPtr);
  receiverPtr->setBtMessageFactory(factoryPtr);
  SharedHandle<BtMessageReceiver> receiver(receiverPtr);

  DefaultBtRequestFactory* reqFactoryPtr(new DefaultBtRequestFactory());
  reqFactoryPtr->setPeer(getPeer());
  reqFactoryPtr->setPieceStorage(pieceStorage);
  reqFactoryPtr->setBtMessageDispatcher(dispatcherPtr);
  reqFactoryPtr->setBtMessageFactory(factoryPtr);
  reqFactoryPtr->setCuid(cuid);
  SharedHandle<BtRequestFactory> reqFactory(reqFactoryPtr);

  DefaultBtInteractive* btInteractivePtr
    (new DefaultBtInteractive(requestGroup_->getDownloadContext(), getPeer()));
  btInteractivePtr->setBtRuntime(btRuntime_);
  btInteractivePtr->setPieceStorage(pieceStorage_);
  btInteractivePtr->setPeerStorage(peerStorage); // Note: Not a member variable.
  btInteractivePtr->setCuid(cuid);
  btInteractivePtr->setBtMessageReceiver(receiver);
  btInteractivePtr->setDispatcher(dispatcher);
  btInteractivePtr->setBtRequestFactory(reqFactory);
  btInteractivePtr->setPeerConnection(peerConnection);
  btInteractivePtr->setExtensionMessageFactory(extensionMessageFactory);
  btInteractivePtr->setExtensionMessageRegistry(exMsgRegistry);
  btInteractivePtr->setKeepAliveInterval
    (getOption()->getAsInt(PREF_BT_KEEP_ALIVE_INTERVAL));
  btInteractivePtr->setRequestGroupMan
    (getDownloadEngine()->getRequestGroupMan().get());
  btInteractivePtr->setBtMessageFactory(factory);
  if((metadataGetMode || !torrentAttrs->privateTorrent) &&
     !getPeer()->isLocalPeer()) {
    if(getOption()->getAsBool(PREF_ENABLE_PEER_EXCHANGE)) {
      btInteractivePtr->setUTPexEnabled(true);
    }
    if(family == AF_INET) {
      if(DHTRegistry::isInitialized()) {
        btInteractivePtr->setDHTEnabled(true);
        factoryPtr->setDHTEnabled(true);
        btInteractivePtr->setLocalNode(DHTRegistry::getData().localNode.get());
      }
    } else {
      if(DHTRegistry::isInitialized6()) {
        btInteractivePtr->setDHTEnabled(true);
        factoryPtr->setDHTEnabled(true);
        btInteractivePtr->setLocalNode(DHTRegistry::getData6().localNode.get());
      }
    }
  }
  btInteractivePtr->setUTMetadataRequestFactory(utMetadataRequestFactory);
  btInteractivePtr->setUTMetadataRequestTracker(utMetadataRequestTracker);
  btInteractivePtr->setTcpPort(e->getBtRegistry()->getTcpPort());
  if(metadataGetMode) {
    btInteractivePtr->enableMetadataGetMode();
  }
  SharedHandle<BtInteractive> btInteractive(btInteractivePtr);

  btInteractive_ = btInteractive;

  // reverse depends
  factoryPtr->setBtMessageDispatcher(dispatcherPtr);
  factoryPtr->setBtRequestFactory(reqFactoryPtr);
  factoryPtr->setPeerConnection(peerConnection.get());

  extensionMessageFactoryPtr->setBtMessageDispatcher(dispatcherPtr);
  extensionMessageFactoryPtr->setBtMessageFactory(factoryPtr);

  if(metadataGetMode) {
    utMetadataRequestFactory->setCuid(cuid);
    utMetadataRequestFactory->setDownloadContext
      (requestGroup_->getDownloadContext());
    utMetadataRequestFactory->setBtMessageDispatcher(dispatcherPtr);
    utMetadataRequestFactory->setBtMessageFactory(factoryPtr);
    utMetadataRequestFactory->setPeer(getPeer());
    utMetadataRequestFactory->setUTMetadataRequestTracker
      (utMetadataRequestTracker.get());
  }

  getPeer()->allocateSessionResource
    (requestGroup_->getDownloadContext()->getPieceLength(),
     requestGroup_->getDownloadContext()->getTotalLength());
  getPeer()->setBtMessageDispatcher(dispatcherPtr);

  btRuntime_->increaseConnections();
  requestGroup_->increaseNumCommand();
}

PeerInteractionCommand::~PeerInteractionCommand() {
  if(getPeer()->getCompletedLength() > 0) {
    pieceStorage_->subtractPieceStats(getPeer()->getBitfield(),
                                      getPeer()->getBitfieldLength());
  }
  getPeer()->releaseSessionResource();

  requestGroup_->decreaseNumCommand();
  btRuntime_->decreaseConnections();
}

bool PeerInteractionCommand::executeInternal() {
  setNoCheck(false);
  bool done = false;
  while(!done) {
    switch(sequence_) {
    case INITIATOR_SEND_HANDSHAKE:
      if(!getSocket()->isWritable(0)) {
        done = true;
        break;
      }
      disableWriteCheckSocket();
      setReadCheckSocket(getSocket());
      //socket->setBlockingMode();
      setTimeout(getOption()->getAsInt(PREF_BT_TIMEOUT));
      btInteractive_->initiateHandshake();
      sequence_ = INITIATOR_WAIT_HANDSHAKE;
      break;
    case INITIATOR_WAIT_HANDSHAKE: {
      if(btInteractive_->countPendingMessage() > 0) {
        btInteractive_->sendPendingMessage();
        if(btInteractive_->countPendingMessage() > 0) {
          done = true;
          break;
        }
      }
      SharedHandle<BtMessage> handshakeMessage =
        btInteractive_->receiveHandshake();
      if(!handshakeMessage) {
        done = true;
        break;
      }
      btInteractive_->doPostHandshakeProcessing();
      sequence_ = WIRED;
      break;
    }
    case RECEIVER_WAIT_HANDSHAKE: {
      SharedHandle<BtMessage> handshakeMessage =
        btInteractive_->receiveAndSendHandshake();
      if(!handshakeMessage) {
        done = true;
        break;
      }
      btInteractive_->doPostHandshakeProcessing();
      sequence_ = WIRED;
      break;
    }
    case WIRED:
      // See the comment for writable check below.
      disableWriteCheckSocket();

      btInteractive_->doInteractionProcessing();
      if(btInteractive_->countReceivedMessageInIteration() > 0) {
        updateKeepAlive();
      }
      if((getPeer()->amInterested() && !getPeer()->peerChoking()) ||
         btInteractive_->countOutstandingRequest() ||
         (getPeer()->peerInterested() && !getPeer()->amChoking())) {

        // Writable check to avoid slow seeding
        if(btInteractive_->isSendingMessageInProgress()) {
          setWriteCheckSocket(getSocket());
        }

        if(getDownloadEngine()->getRequestGroupMan()->
           doesOverallDownloadSpeedExceed() ||
           requestGroup_->doesDownloadSpeedExceed()) {
          disableReadCheckSocket();
          setNoCheck(true);
        } else {
          setReadCheckSocket(getSocket());
        }
      } else {
        disableReadCheckSocket();
      }
      done = true;
      break;
    }
  }
  if(btInteractive_->countPendingMessage() > 0) {
    setNoCheck(true);
  }
  getDownloadEngine()->addCommand(this);
  return false;
}

// TODO this method removed when PeerBalancerCommand is implemented
bool PeerInteractionCommand::prepareForNextPeer(time_t wait) {
  if(peerStorage_->isPeerAvailable() && btRuntime_->lessThanEqMinPeers()) {
    SharedHandle<Peer> peer = peerStorage_->getUnusedPeer();
    peer->usedBy(getDownloadEngine()->newCUID());
    PeerInitiateConnectionCommand* command =
      new PeerInitiateConnectionCommand
      (peer->usedBy(), requestGroup_, peer, getDownloadEngine(), btRuntime_);
    command->setPeerStorage(peerStorage_);
    command->setPieceStorage(pieceStorage_);
    getDownloadEngine()->addCommand(command);
  }
  return true;
}

void PeerInteractionCommand::onAbort() {
  btInteractive_->cancelAllPiece();
  peerStorage_->returnPeer(getPeer());
}

void PeerInteractionCommand::onFailure(const Exception& err)
{
  requestGroup_->setLastErrorCode(err.getErrorCode());
  requestGroup_->setHaltRequested(true);
  getDownloadEngine()->setRefreshInterval(0);
}

bool PeerInteractionCommand::exitBeforeExecute()
{
  return btRuntime_->isHalt();
}

const SharedHandle<Option>& PeerInteractionCommand::getOption() const
{
  return requestGroup_->getOption();
}

} // namespace aria2