~paulbrianstewart/quassel/833751-String-Error-Fix

/***************************************************************************
 *   Copyright (C) 2005-2010 by the Quassel Project                        *
 *   devel@quassel-irc.org                                                 *
 *                                                                         *
 *   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) version 3.                                           *
 *                                                                         *
 *   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.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

#include "ircparser.h"

#include "corenetwork.h"
#include "eventmanager.h"
#include "ircevent.h"
#include "messageevent.h"
#include "networkevent.h"

#ifdef HAVE_QCA2
#  include "cipher.h"
#endif

IrcParser::IrcParser(CoreSession *session) :
  QObject(session),
  _coreSession(session)
{

}

bool IrcParser::checkParamCount(const QString &cmd, const QList<QByteArray> &params, int minParams) {
  if(params.count() < minParams) {
    qWarning() << "Expected" << minParams << "params for IRC command" << cmd << ", got:" << params;
    return false;
  }
  return true;
}

QByteArray IrcParser::decrypt(Network *network, const QString &bufferName, const QByteArray &message, bool isTopic) {
#ifdef HAVE_QCA2
  if(message.isEmpty())
    return message;

  if(!Cipher::neededFeaturesAvailable())
    return message;

  Cipher *cipher = qobject_cast<CoreNetwork *>(network)->cipher(bufferName);
  if(!cipher)
    return message;

  return isTopic? cipher->decryptTopic(message) : cipher->decrypt(message);
#else
  Q_UNUSED(network);
  Q_UNUSED(bufferName);
  Q_UNUSED(isTopic);
  return message;
#endif
}

/* parse the raw server string and generate an appropriate event */
/* used to be handleServerMsg()                                  */
void IrcParser::processNetworkIncoming(NetworkDataEvent *e) {
  CoreNetwork *net = qobject_cast<CoreNetwork *>(e->network());
  if(!net) {
    qWarning() << "Received network event without valid network pointer!";
    return;
  }

  // note that the IRC server is still alive
  net->resetPingTimeout();

  QByteArray msg = e->data();
  if(msg.isEmpty()) {
    qWarning() << "Received empty string from server!";
    return;
  }

  // Now we split the raw message into its various parts...
  QString prefix;
  QByteArray trailing;
  QString cmd, target;

  // First, check for a trailing parameter introduced by " :", since this might screw up splitting the msg
  // NOTE: This assumes that this is true in raw encoding, but well, hopefully there are no servers running in japanese on protocol level...
  int idx = msg.indexOf(" :");
  if(idx >= 0) {
    if(msg.length() > idx + 2)
      trailing = msg.mid(idx + 2);
    msg = msg.left(idx);
  }
  // OK, now it is safe to split...
  QList<QByteArray> params = msg.split(' ');

  // This could still contain empty elements due to (faulty?) ircds sending multiple spaces in a row
  // Also, QByteArray is not nearly as convenient to work with as QString for such things :)
  QList<QByteArray>::iterator iter = params.begin();
  while(iter != params.end()) {
    if(iter->isEmpty())
      iter = params.erase(iter);
    else
      ++iter;
  }

  if(!trailing.isEmpty())
    params << trailing;
  if(params.count() < 1) {
    qWarning() << "Received invalid string from server!";
    return;
  }

  QString foo = net->serverDecode(params.takeFirst());

  // a colon as the first chars indicates the existence of a prefix
  if(foo[0] == ':') {
    foo.remove(0, 1);
    prefix = foo;
    if(params.count() < 1) {
      qWarning() << "Received invalid string from server!";
      return;
    }
    foo = net->serverDecode(params.takeFirst());
  }

  // next string without a whitespace is the command
  cmd = foo.trimmed();

  QList<Event *> events;
  EventManager::EventType type = EventManager::Invalid;

  // numeric replies have the target as first param (RFC 2812 - 2.4). this is usually our own nick. Remove this!
  uint num = cmd.toUInt();
  if(num > 0) {
    if(params.count() == 0) {
      qWarning() << "Message received from server violates RFC and is ignored!" << msg;
      return;
    }
    target = net->serverDecode(params.takeFirst());
    type = EventManager::IrcEventNumeric;
  } else {
    QString typeName = QLatin1String("IrcEvent") + cmd.at(0).toUpper() + cmd.mid(1).toLower();
    type = eventManager()->eventTypeByName(typeName);
    if(type == EventManager::Invalid) {
      type = eventManager()->eventTypeByName("IrcEventUnknown");
      Q_ASSERT(type != EventManager::Invalid);
    }
    target = QString();
  }

  // Almost always, all params are server-encoded. There's a few exceptions, let's catch them here!
  // Possibly not the best option, we might want something more generic? Maybe yet another layer of
  // unencoded events with event handlers for the exceptions...
  // Also, PRIVMSG and NOTICE need some special handling, we put this in here as well, so we get out
  // nice pre-parsed events that the CTCP handler can consume.

  QStringList decParams;
  bool defaultHandling = true; // whether to automatically copy the remaining params and send the event

  switch(type) {

  case EventManager::IrcEventPrivmsg:
    defaultHandling = false; // this might create a list of events

    if(checkParamCount(cmd, params, 1)) {
      QString senderNick = nickFromMask(prefix);
      QByteArray msg = params.count() < 2 ? QByteArray() : params.at(1);

      QStringList targets = net->serverDecode(params.at(0)).split(',', QString::SkipEmptyParts);
      QStringList::const_iterator targetIter;
      for(targetIter = targets.constBegin(); targetIter != targets.constEnd(); ++targetIter) {
        QString target = net->isChannelName(*targetIter) ? *targetIter : senderNick;

        msg = decrypt(net, target, msg);

        events << new IrcEventRawMessage(EventManager::IrcEventRawPrivmsg, net, msg, prefix, target, e->timestamp());
      }
    }
    break;

  case EventManager::IrcEventNotice:
    defaultHandling = false;

    if(checkParamCount(cmd, params, 2)) {
      QStringList targets = net->serverDecode(params.at(0)).split(',', QString::SkipEmptyParts);
      QStringList::const_iterator targetIter;
      for(targetIter = targets.constBegin(); targetIter != targets.constEnd(); ++targetIter) {
        QString target = *targetIter;

        // special treatment for welcome messages like:
        // :ChanServ!ChanServ@services. NOTICE egst :[#apache] Welcome, this is #apache. Please read the in-channel topic message. This channel is being logged by IRSeekBot. If you have any question please see http://blog.freenode.net/?p=68
        if(!net->isChannelName(target)) {
          QString decMsg = net->serverDecode(params.at(1));
          QRegExp welcomeRegExp("^\\[([^\\]]+)\\] ");
          if(welcomeRegExp.indexIn(decMsg) != -1) {
            QString channelname = welcomeRegExp.cap(1);
            decMsg = decMsg.mid(welcomeRegExp.matchedLength());
            CoreIrcChannel *chan = static_cast<CoreIrcChannel *>(net->ircChannel(channelname)); // we only have CoreIrcChannels in the core, so this cast is safe
            if(chan && !chan->receivedWelcomeMsg()) {
              chan->setReceivedWelcomeMsg();
              events << new MessageEvent(Message::Notice, net, decMsg, prefix, channelname, Message::None, e->timestamp());
              continue;
            }
          }
        }

        if(prefix.isEmpty() || target == "AUTH") {
          target = QString();
        } else {
          if(!target.isEmpty() && net->prefixes().contains(target.at(0)))
            target = target.mid(1);
          if(!net->isChannelName(target))
            target = nickFromMask(prefix);
        }
        events << new IrcEventRawMessage(EventManager::IrcEventRawNotice, net, params[1], prefix, target, e->timestamp());
      }
    }
    break;

    // the following events need only special casing for param decoding
  case EventManager::IrcEventKick:
    if(params.count() >= 3) { // we have a reason
      decParams << net->serverDecode(params.at(0)) << net->serverDecode(params.at(1));
      decParams << net->channelDecode(decParams.first(), params.at(2)); // kick reason
    }
    break;

  case EventManager::IrcEventPart:
    if(params.count() >= 2) {
      QString channel = net->serverDecode(params.at(0));
      decParams << channel;
      decParams << net->userDecode(nickFromMask(prefix), params.at(1));
    }
    break;

  case EventManager::IrcEventQuit:
    if(params.count() >= 1) {
      decParams << net->userDecode(nickFromMask(prefix), params.at(0));
    }
    break;

  case EventManager::IrcEventTopic:
    if(params.count() >= 1) {
      QString channel = net->serverDecode(params.at(0));
      decParams << channel;
      decParams << (params.count() >= 2? net->channelDecode(channel, decrypt(net, channel, params.at(1), true)) : QString());
    }
    break;

  case EventManager::IrcEventNumeric:
    switch(num) {
    case 301:  /* RPL_AWAY */
      if(params.count() >= 2) {
        QString nick = net->serverDecode(params.at(0));
        decParams << nick;
        decParams << net->userDecode(nick, params.at(1));
      }
      break;

    case 332:  /* RPL_TOPIC */
      if(params.count() >= 2) {
        QString channel = net->serverDecode(params.at(0));
        decParams << channel;
        decParams << net->channelDecode(channel, decrypt(net, channel, params.at(1), true));
      }
      break;

    case 333:  /* Topic set by... */
      if(params.count() >= 2) {
        QString channel = net->serverDecode(params.at(0));
        decParams << channel << net->serverDecode(params.at(1));
        decParams << net->channelDecode(channel, params.at(2));
      }
      break;
    }

  default:
    break;
  }

  if(defaultHandling && type != EventManager::Invalid) {
    for(int i = decParams.count(); i < params.count(); i++)
      decParams << net->serverDecode(params.at(i));

    IrcEvent *event;
    if(type == EventManager::IrcEventNumeric)
      event = new IrcEventNumeric(num, net, prefix, target);
    else
      event = new IrcEvent(type, net, prefix);
    event->setParams(decParams);
    event->setTimestamp(e->timestamp());
    events << event;
  }

  foreach(Event *event, events) {
    coreSession()->eventManager()->sendEvent(event);
  }
}