Replace deprecated qSort with std::sort
[quassel.git] / src / core / coresessioneventprocessor.cpp
index a47b2c0..86b4cde 100644 (file)
@@ -1,5 +1,5 @@
 /***************************************************************************
- *   Copyright (C) 2005-2015 by the Quassel Project                        *
+ *   Copyright (C) 2005-2019 by the Quassel Project                        *
  *   devel@quassel-irc.org                                                 *
  *                                                                         *
  *   This program is free software; you can redistribute it and/or modify  *
 #include "ctcpevent.h"
 #include "ircevent.h"
 #include "ircuser.h"
-#include "logger.h"
 #include "messageevent.h"
 #include "netsplit.h"
 #include "quassel.h"
 
 #ifdef HAVE_QCA2
-#  include "keyevent.h"
+#    include "keyevent.h"
 #endif
 
-CoreSessionEventProcessor::CoreSessionEventProcessor(CoreSession *session)
-    : BasicHandler("handleCtcp", session),
-    _coreSession(session)
+// IRCv3 capabilities
+#include "irccap.h"
+
+CoreSessionEventProcessor::CoreSessionEventProcessor(CoreSession* session)
+    : BasicHandler("handleCtcp", session)
+    , _coreSession(session)
 {
-    connect(coreSession(), SIGNAL(networkDisconnected(NetworkId)), this, SLOT(destroyNetsplits(NetworkId)));
-    connect(this, SIGNAL(newEvent(Event *)), coreSession()->eventManager(), SLOT(postEvent(Event *)));
+    connect(coreSession(), &CoreSession::networkDisconnected, this, &CoreSessionEventProcessor::destroyNetsplits);
+    connect(this, &CoreSessionEventProcessor::newEvent, coreSession()->eventManager(), &EventManager::postEvent);
 }
 
-
-bool CoreSessionEventProcessor::checkParamCount(IrcEvent *e, int minParams)
+bool CoreSessionEventProcessor::checkParamCount(IrcEvent* e, int minParams)
 {
     if (e->params().count() < minParams) {
         if (e->type() == EventManager::IrcEventNumeric) {
-            qWarning() << "Command " << static_cast<IrcEventNumeric *>(e)->number() << " requires " << minParams << "params, got: " << e->params();
+            qWarning() << "Command " << static_cast<IrcEventNumeric*>(e)->number() << " requires " << minParams
+                       << "params, got: " << e->params();
         }
         else {
             QString name = coreSession()->eventManager()->enumName(e->type());
@@ -62,8 +64,7 @@ bool CoreSessionEventProcessor::checkParamCount(IrcEvent *e, int minParams)
     return true;
 }
 
-
-void CoreSessionEventProcessor::tryNextNick(NetworkEvent *e, const QString &errnick, bool erroneus)
+void CoreSessionEventProcessor::tryNextNick(NetworkEvent* e, const QString& errnick, bool erroneus)
 {
     QStringList desiredNicks = coreSession()->identity(e->network()->identity())->nicks();
     int nextNickIdx = desiredNicks.indexOf(errnick) + 1;
@@ -74,9 +75,13 @@ void CoreSessionEventProcessor::tryNextNick(NetworkEvent *e, const QString &errn
     else {
         if (erroneus) {
             // FIXME Make this an ErrorEvent or something like that, so it's translated in the client
-            MessageEvent *msgEvent = new MessageEvent(Message::Error, e->network(),
-                tr("No free and valid nicks in nicklist found. use: /nick <othernick> to continue"),
-                QString(), QString(), Message::None, e->timestamp());
+            MessageEvent* msgEvent = new MessageEvent(Message::Error,
+                                                      e->network(),
+                                                      tr("No free and valid nicks in nicklist found. use: /nick <othernick> to continue"),
+                                                      QString(),
+                                                      QString(),
+                                                      Message::None,
+                                                      e->timestamp());
             emit newEvent(msgEvent);
             return;
         }
@@ -88,20 +93,26 @@ void CoreSessionEventProcessor::tryNextNick(NetworkEvent *e, const QString &errn
     coreNetwork(e)->putRawLine("NICK " + coreNetwork(e)->encodeServerString(nextNick));
 }
 
-
-void CoreSessionEventProcessor::processIrcEventNumeric(IrcEventNumeric *e)
+void CoreSessionEventProcessor::processIrcEventNumeric(IrcEventNumeric* e)
 {
     switch (e->number()) {
     // SASL authentication replies
     // See: http://ircv3.net/specs/extensions/sasl-3.1.html
+
+    // case 900:  // RPL_LOGGEDIN
+    // case 901:  // RPL_LOGGEDOUT
+    // Don't use 900 or 901 for updating the local hostmask.  Unreal 3.2 gives it as the IP address
+    // even when cloaked.
+    // Every other reply should result in moving on
     // TODO Handle errors to stop connection if appropriate
+    case 902:  // ERR_NICKLOCKED
     case 903:  // RPL_SASLSUCCESS
     case 904:  // ERR_SASLFAIL
     case 905:  // ERR_SASLTOOLONG
     case 906:  // ERR_SASLABORTED
     case 907:  // ERR_SASLALREADY
         // Move on to the next capability
-        sendNextCap(e->network());
+        coreNetwork(e)->sendNextCap();
         break;
 
     default:
@@ -109,8 +120,7 @@ void CoreSessionEventProcessor::processIrcEventNumeric(IrcEventNumeric *e)
     }
 }
 
-
-void CoreSessionEventProcessor::processIrcEventAuthenticate(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventAuthenticate(IrcEvent* e)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -120,7 +130,7 @@ void CoreSessionEventProcessor::processIrcEventAuthenticate(IrcEvent *e)
         return;
     }
 
-    CoreNetwork *net = coreNetwork(e);
+    CoreNetworknet = coreNetwork(e);
 
 #ifdef HAVE_SSL
     if (net->identityPtr()->sslCert().isNull()) {
@@ -134,149 +144,285 @@ void CoreSessionEventProcessor::processIrcEventAuthenticate(IrcEvent *e)
         saslData.prepend("AUTHENTICATE ");
         net->putRawLine(saslData);
 #ifdef HAVE_SSL
-    } else {
+    }
+    else {
         net->putRawLine("AUTHENTICATE +");
     }
 #endif
 }
 
-void CoreSessionEventProcessor::sendNextCap(Network *net)
-{
-    CoreNetwork *coreNet = qobject_cast<CoreNetwork *>(net);
-    if (coreNet->capNegotiationInProgress()) {
-        // Request the next capability and remove it from the list
-        // Handle one at a time so one capability failing won't NAK all of 'em
-        coreNet->putRawLine(coreNet->serverEncode(QString("CAP REQ :%1").arg(coreNet->takeQueuedCap())));
-    } else {
-        // If SASL requested but not available, print a warning
-        if (coreNet->networkInfo().useSasl && !coreNet->useCapSASL())
-            emit newEvent(new MessageEvent(Message::Error, net, tr("SASL authentication not supported by server, continuing without"), QString(), QString(), Message::None, QDateTime::currentDateTimeUtc()));
-
-        // No pending desired capabilities, end negotiation
-        coreNet->putRawLine(coreNet->serverEncode(QString("CAP END")));
-        emit newEvent(new MessageEvent(Message::Server, net, tr("Capability negotiation finished"), QString(), QString(), Message::None, QDateTime::currentDateTimeUtc()));
-    }
-}
-
-void CoreSessionEventProcessor::processIrcEventCap(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventCap(IrcEvent* e)
 {
     // Handle capability negotiation
     // See: http://ircv3.net/specs/core/capability-negotiation-3.2.html
     // And: http://ircv3.net/specs/core/capability-negotiation-3.1.html
-    if (e->params().count() >= 3) {
-        CoreNetwork *coreNet = coreNetwork(e);
-        if (e->params().at(1).compare("LS", Qt::CaseInsensitive) == 0) {
-            // Server: CAP * LS * :multi-prefix extended-join account-notify batch invite-notify tls
-            // Server: CAP * LS * :cap-notify server-time example.org/dummy-cap=dummyvalue example.org/second-dummy-cap
-            // Server: CAP * LS :userhost-in-names sasl=EXTERNAL,DH-AES,DH-BLOWFISH,ECDSA-NIST256P-CHALLENGE,PLAIN
-            bool capListFinished;
-            QStringList availableCaps;
-            if (e->params().count() == 4) {
-                // Middle of multi-line reply, ignore the asterisk
-                capListFinished = false;
-                availableCaps = e->params().at(3).split(' ');
-            } else {
-                // Single line reply
-                capListFinished = true;
+
+    // All commands require at least 2 parameters
+    if (!checkParamCount(e, 2))
+        return;
+
+    CoreNetwork* coreNet = coreNetwork(e);
+    QString capCommand = e->params().at(1).trimmed().toUpper();
+    if (capCommand == "LS" || capCommand == "NEW") {
+        // Either we've gotten a list of capabilities, or new capabilities we may want
+        // Server: CAP * LS * :multi-prefix extended-join account-notify batch invite-notify tls
+        // Server: CAP * LS * :cap-notify server-time example.org/dummy-cap=dummyvalue example.org/second-dummy-cap
+        // Server: CAP * LS :userhost-in-names sasl=EXTERNAL,DH-AES,DH-BLOWFISH,ECDSA-NIST256P-CHALLENGE,PLAIN
+        bool capListFinished;
+        QStringList availableCaps;
+        if (e->params().count() == 4) {
+            // Middle of multi-line reply, ignore the asterisk
+            capListFinished = false;
+            availableCaps = e->params().at(3).split(' ');
+        }
+        else {
+            // Single line reply
+            capListFinished = true;
+            if (e->params().count() >= 3) {
+                // Some capabilities are specified, add them
                 availableCaps = e->params().at(2).split(' ');
             }
-            // We know what capabilities are available, request what we want.
-            QStringList availableCapPair;
-            bool queueCurrentCap;
-            for (int i = 0; i < availableCaps.count(); ++i) {
-                // Capability may include values, e.g. CAP * LS :multi-prefix sasl=EXTERNAL
-                availableCapPair = availableCaps[i].trimmed().split('=');
-                queueCurrentCap = false;
-                if (availableCapPair.at(0).startsWith("sasl")) {
-                    // Only request SASL if it's enabled
-                    if (coreNet->networkInfo().useSasl)
-                        queueCurrentCap = true;
-                }
-                if (queueCurrentCap) {
-                    if(availableCapPair.count() >= 2)
-                        coreNet->queuePendingCap(availableCapPair.at(0).trimmed(), availableCapPair.at(1).trimmed());
-                    else
-                        coreNet->queuePendingCap(availableCapPair.at(0).trimmed());
-                }
-            }
-            // Begin capability requests when capability listing complete
-            if (capListFinished) {
-                emit newEvent(new MessageEvent(Message::Server, e->network(), tr("Negotiating capabilities..."), QString(), QString(), Message::None, e->timestamp()));
-                sendNextCap(coreNet);
+            else {
+                // No capabilities available, add an empty list
+                availableCaps = QStringList();
             }
-        } else if (e->params().at(1).compare("ACK", Qt::CaseInsensitive) == 0) {
-            // Server: CAP * ACK :multi-prefix sasl
-            // Got the capability we want, enable, handle as needed.
-            // As only one capability is requested at a time, no need to split
-            // Lower-case the list to make later comparisons easier
+        }
+        // Sort capabilities before requesting for consistency among networks.  This may avoid
+        // unexpected cases when some networks offer capabilities in a different order than
+        // others.  It also looks nicer in logs.  Not required.
+        availableCaps.sort();
+        // Store what capabilities are available
+        QString availableCapName, availableCapValue;
+        for (int i = 0; i < availableCaps.count(); ++i) {
             // Capability may include values, e.g. CAP * LS :multi-prefix sasl=EXTERNAL
-            QStringList acceptedCap = e->params().at(2).trimmed().split('=');
+            // Capability name comes before the first '='.  If no '=' exists, this gets the
+            // whole string instead.
+            availableCapName = availableCaps[i].section('=', 0, 0).trimmed();
+            // Some capabilities include multiple key=value pairs in the listing,
+            // e.g. "sts=duration=31536000,port=6697"
+            // Include everything after the first equal sign as part of the value.  If no '='
+            // exists, this gets an empty string.
+            availableCapValue = availableCaps[i].section('=', 1).trimmed();
+            // Only add the capability if it's non-empty
+            if (!availableCapName.isEmpty()) {
+                coreNet->addCap(availableCapName, availableCapValue);
+            }
+        }
+
+        // Begin capability requests when capability listing complete
+        if (capListFinished)
+            coreNet->beginCapNegotiation();
+    }
+    else if (capCommand == "ACK") {
+        // CAP ACK requires at least 3 parameters (no empty response allowed)
+        if (!checkParamCount(e, 3)) {
+            // If an invalid reply is sent, try to continue rather than getting stuck.
+            coreNet->sendNextCap();
+            return;
+        }
+
+        // Server: CAP * ACK :multi-prefix sasl
+        // Got the capabilities we want, handle as needed.
+        QStringList acceptedCaps;
+        acceptedCaps = e->params().at(2).split(' ');
 
+        // Store what capability was acknowledged
+        QString acceptedCap;
+
+        // Keep track of whether or not a capability requires further configuration.  Due to queuing
+        // logic in CoreNetwork::queueCap(), this shouldn't ever happen when more than one
+        // capability is requested, but it's better to handle edge cases or faulty servers.
+        bool capsRequireConfiguration = false;
+
+        for (int i = 0; i < acceptedCaps.count(); ++i) {
+            acceptedCap = acceptedCaps[i].trimmed().toLower();
             // Mark this cap as accepted
-            if(acceptedCap.count() >= 2)
-                coreNet->addCap(acceptedCap.at(0), acceptedCap.at(1));
-            else
-                coreNet->addCap(acceptedCap.at(0));
-
-            // Handle special cases
-            if (acceptedCap.at(0).startsWith("sasl")) {
-                // Freenode (at least) sends "sasl " with a trailing space for some reason!
-                // if the current identity has a cert set, use SASL EXTERNAL
-                // FIXME use event
-                // TODO If value of sasl capability is not empty, limit to accepted
-#ifdef HAVE_SSL
-                if (!coreNet->identityPtr()->sslCert().isNull()) {
-                    coreNet->putRawLine(coreNet->serverEncode("AUTHENTICATE EXTERNAL"));
-                } else {
-#endif
-                    // Only working with PLAIN atm, blowfish later
-                    coreNet->putRawLine(coreNet->serverEncode("AUTHENTICATE PLAIN"));
-#ifdef HAVE_SSL
-                }
-#endif
-            } else {
-                // Special handling not needed, move on to next cap
-                sendNextCap(coreNet);
+            coreNet->acknowledgeCap(acceptedCap);
+            if (!capsRequireConfiguration && coreNet->capsRequiringConfiguration.contains(acceptedCap)) {
+                capsRequireConfiguration = true;
+                // Some capabilities (e.g. SASL) require further messages to finish.  If so, do NOT
+                // send the next capability; it will be handled elsewhere in CoreNetwork.
+                // Otherwise, allow moving on to the next capability.
             }
-        } else if (e->params().at(1).compare("NAK", Qt::CaseInsensitive) == 0) {
-            // Something went wrong with this capability, disable, go to next cap
-            // As only one capability is requested at a time, no need to split
-            // Lower-case the list to make later comparisons easier
-            QString deniedCap = e->params().at(2).trimmed();
-            coreNet->removeCap(deniedCap);
-            sendNextCap(coreNet);
+        }
+
+        if (!capsRequireConfiguration) {
+            // No additional configuration required, move on to the next capability
+            coreNet->sendNextCap();
+        }
+    }
+    else if (capCommand == "NAK" || capCommand == "DEL") {
+        // CAP NAK/DEL require at least 3 parameters (no empty response allowed)
+        if (!checkParamCount(e, 3)) {
+            if (capCommand == "NAK") {
+                // If an invalid reply is sent, try to continue rather than getting stuck.  This
+                // only matters for denied caps, not removed caps.
+                coreNet->sendNextCap();
+            }
+            return;
+        }
+
+        // Either something went wrong with the capabilities, or they are no longer supported
+        // > For CAP NAK
+        // Server: CAP * NAK :multi-prefix sasl
+        // > For CAP DEL
+        // Server: :irc.example.com CAP modernclient DEL :multi-prefix sasl
+        // CAP NAK and CAP DEL replies are always single-line
+
+        QStringList removedCaps;
+        removedCaps = e->params().at(2).split(' ');
+
+        // Store the capabilities that were denied or removed
+        QString removedCap;
+        for (int i = 0; i < removedCaps.count(); ++i) {
+            removedCap = removedCaps[i].trimmed().toLower();
+            // Mark this cap as removed.
+            // For CAP DEL, removes it from use.
+            // For CAP NAK when received before negotiation enabled these capabilities, removeCap()
+            // should do nothing.  This merely guards against non-spec servers sending an
+            // unsolicited CAP ACK then later removing that capability.
+            coreNet->removeCap(removedCap);
+        }
+
+        if (capCommand == "NAK") {
+            // Continue negotiation only if this is the result of denied caps, not removed caps
+            if (removedCaps.count() > 1) {
+                // We've received a CAP NAK reply to multiple capabilities at once.  Unfortunately,
+                // we don't know which capability failed and which ones are valid to re-request, so
+                // individually retry each capability from the failed bundle.
+                // See CoreNetwork::retryCapsIndividually() for more details.
+                coreNet->retryCapsIndividually();
+                // Still need to call sendNextCap() to carry on.
+            }
+            // Carry on with negotiation
+            coreNet->sendNextCap();
         }
     }
 }
 
+/* IRCv3 account-notify
+ * Log in:  ":nick!user@host ACCOUNT accountname"
+ * Log out: ":nick!user@host ACCOUNT *" */
+void CoreSessionEventProcessor::processIrcEventAccount(IrcEvent* e)
+{
+    if (!checkParamCount(e, 1))
+        return;
 
-void CoreSessionEventProcessor::processIrcEventInvite(IrcEvent *e)
+    IrcUser* ircuser = e->network()->updateNickFromMask(e->prefix());
+    if (ircuser) {
+        // WHOX uses '0' to indicate logged-out, account-notify and extended-join uses '*'.
+        // As '*' is used internally to represent logged-out, no need to handle that differently.
+        ircuser->setAccount(e->params().at(0));
+    }
+    else {
+        qDebug() << "Received account-notify data for unknown user" << e->prefix();
+    }
+}
+
+/* IRCv3 away-notify - ":nick!user@host AWAY [:message]" */
+void CoreSessionEventProcessor::processIrcEventAway(IrcEvent* e)
+{
+    if (!checkParamCount(e, 1))
+        return;
+    // Don't use checkParamCount(e, 2) since the message is optional.  Some servers respond in a way
+    // that it counts as two parameters, but we shouldn't rely on that.
+
+    // Nick is sent as part of parameters in order to split user/server decoding
+    IrcUser* ircuser = e->network()->ircUser(e->params().at(0));
+    if (ircuser) {
+        // If two parameters are sent -and- the second parameter isn't empty, then user is away.
+        // Otherwise, mark them as not away.
+        if (e->params().count() >= 2 && !e->params().at(1).isEmpty()) {
+            ircuser->setAway(true);
+            ircuser->setAwayMessage(e->params().at(1));
+        }
+        else {
+            ircuser->setAway(false);
+        }
+    }
+    else {
+        qDebug() << "Received away-notify data for unknown user" << e->params().at(0);
+    }
+}
+
+/* IRCv3 chghost - ":nick!user@host CHGHOST newuser new.host.goes.here" */
+void CoreSessionEventProcessor::processIrcEventChghost(IrcEvent* e)
+{
+    if (!checkParamCount(e, 2))
+        return;
+
+    IrcUser* ircuser = e->network()->updateNickFromMask(e->prefix());
+    if (ircuser) {
+        // Update with new user/hostname information.  setUser/setHost handles checking what
+        // actually changed.
+        ircuser->setUser(e->params().at(0));
+        ircuser->setHost(e->params().at(1));
+    }
+    else {
+        qDebug() << "Received chghost data for unknown user" << e->prefix();
+    }
+}
+
+void CoreSessionEventProcessor::processIrcEventInvite(IrcEvent* e)
 {
     if (checkParamCount(e, 2)) {
         e->network()->updateNickFromMask(e->prefix());
     }
 }
 
-
-void CoreSessionEventProcessor::processIrcEventJoin(IrcEvent *e)
+/*  JOIN: ":<nick!user@host> JOIN <channel>" */
+void CoreSessionEventProcessor::processIrcEventJoin(IrcEvente)
 {
-    if (e->testFlag(EventManager::Fake)) // generated by handleEarlyNetsplitJoin
+    if (e->testFlag(EventManager::Fake))  // generated by handleEarlyNetsplitJoin
         return;
 
     if (!checkParamCount(e, 1))
         return;
 
-    CoreNetwork *net = coreNetwork(e);
+    CoreNetworknet = coreNetwork(e);
     QString channel = e->params()[0];
-    IrcUser *ircuser = net->updateNickFromMask(e->prefix());
+    IrcUser* ircuser = net->updateNickFromMask(e->prefix());
+
+    if (net->capEnabled(IrcCap::EXTENDED_JOIN)) {
+        if (e->params().count() < 3) {
+            // Some IRC servers don't send extended-join events in all situations.  Rather than
+            // ignore the join entirely, treat it as a regular join with a debug-level log entry.
+            // See:  https://github.com/inspircd/inspircd/issues/821
+            qDebug() << "extended-join requires 3 params, got:" << e->params()
+                     << ", handling as a "
+                        "regular join";
+        }
+        else {
+            // If logged in, :nick!user@host JOIN #channelname accountname :Real Name
+            // If logged out, :nick!user@host JOIN #channelname * :Real Name
+            // See:  http://ircv3.net/specs/extensions/extended-join-3.1.html
+            // WHOX uses '0' to indicate logged-out, account-notify and extended-join uses '*'.
+            // As '*' is used internally to represent logged-out, no need to handle that differently.
+            ircuser->setAccount(e->params()[1]);
+            // Update the user's real name, too
+            ircuser->setRealName(e->params()[2]);
+        }
+    }
+    // Else :nick!user@host JOIN #channelname
 
     bool handledByNetsplit = false;
-    foreach(Netsplit* n, _netsplits.value(e->network())) {
+    for (Netsplit* n : _netsplits.value(e->network())) {
         handledByNetsplit = n->userJoined(e->prefix(), channel);
         if (handledByNetsplit)
             break;
     }
 
+    // With "away-notify" enabled, some IRC servers forget to send :away messages for users who join
+    // channels while away.  Unfortunately, working around this involves WHO'ng every single user as
+    // they join, which is not very efficient.  If at all possible, it's better to get the issue
+    // fixed in the IRC server instead.
+    //
+    // If pursuing a workaround instead, this is where you'd do it.  Check the version control
+    // history for the commit that added this comment to see how to implement it - there's some
+    // unexpected situations to watch out for!
+    //
+    // See https://ircv3.net/specs/extensions/away-notify-3.1.html
+
     if (!handledByNetsplit)
         ircuser->joinChannel(channel);
     else
@@ -284,26 +430,26 @@ void CoreSessionEventProcessor::processIrcEventJoin(IrcEvent *e)
 
     if (net->isMe(ircuser)) {
         net->setChannelJoined(channel);
+        // Mark the message as Self
+        e->setFlag(EventManager::Self);
         // FIXME use event
-        net->putRawLine(net->serverEncode("MODE " + channel)); // we want to know the modes of the channel we just joined, so we ask politely
+        net->putRawLine(net->serverEncode("MODE " + channel));  // we want to know the modes of the channel we just joined, so we ask politely
     }
 }
 
-
-void CoreSessionEventProcessor::lateProcessIrcEventKick(IrcEvent *e)
+void CoreSessionEventProcessor::lateProcessIrcEventKick(IrcEvent* e)
 {
     if (checkParamCount(e, 2)) {
         e->network()->updateNickFromMask(e->prefix());
-        IrcUser *victim = e->network()->ircUser(e->params().at(1));
+        IrcUservictim = e->network()->ircUser(e->params().at(1));
         if (victim) {
             victim->partChannel(e->params().at(0));
-            //if(e->network()->isMe(victim)) e->network()->setKickedFromChannel(channel);
+            // if(e->network()->isMe(victim)) e->network()->setKickedFromChannel(channel);
         }
     }
 }
 
-
-void CoreSessionEventProcessor::processIrcEventMode(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventMode(IrcEvent* e)
 {
     if (!checkParamCount(e, 2))
         return;
@@ -311,49 +457,49 @@ void CoreSessionEventProcessor::processIrcEventMode(IrcEvent *e)
     if (e->network()->isChannelName(e->params().first())) {
         // Channel Modes
 
-        IrcChannel *channel = e->network()->ircChannel(e->params()[0]);
+        IrcChannelchannel = e->network()->ircChannel(e->params()[0]);
         if (!channel) {
-            // we received mode information for a channel we're not in. that means probably we've just been kicked out or something like that
-            // anyways: we don't have a place to store the data --> discard the info.
+            // we received mode information for a channel we're not in. that means probably we've just been kicked out or something like
+            // that anyways: we don't have a place to store the data --> discard the info.
             return;
         }
 
         QString modes = e->params()[1];
         bool add = true;
         int paramOffset = 2;
-        for (int c = 0; c < modes.length(); c++) {
-            if (modes[c] == '+') {
+        for (auto mode : modes) {
+            if (mode == '+') {
                 add = true;
                 continue;
             }
-            if (modes[c] == '-') {
+            if (mode == '-') {
                 add = false;
                 continue;
             }
 
-            if (e->network()->prefixModes().contains(modes[c])) {
+            if (e->network()->prefixModes().contains(mode)) {
                 // user channel modes (op, voice, etc...)
                 if (paramOffset < e->params().count()) {
-                    IrcUser *ircUser = e->network()->ircUser(e->params()[paramOffset]);
+                    IrcUserircUser = e->network()->ircUser(e->params()[paramOffset]);
                     if (!ircUser) {
                         qWarning() << Q_FUNC_INFO << "Unknown IrcUser:" << e->params()[paramOffset];
                     }
                     else {
                         if (add) {
                             bool handledByNetsplit = false;
-                            QHash<QString, Netsplit *> splits = _netsplits.value(e->network());
-                            foreach(Netsplit* n, _netsplits.value(e->network())) {
+                            QHash<QString, Netsplit*> splits = _netsplits.value(e->network());
+                            for (Netsplit* n : _netsplits.value(e->network())) {
                                 handledByNetsplit = n->userAlreadyJoined(ircUser->hostmask(), channel->name());
                                 if (handledByNetsplit) {
-                                    n->addMode(ircUser->hostmask(), channel->name(), QString(modes[c]));
+                                    n->addMode(ircUser->hostmask(), channel->name(), QString(mode));
                                     break;
                                 }
                             }
                             if (!handledByNetsplit)
-                                channel->addUserMode(ircUser, QString(modes[c]));
+                                channel->addUserMode(ircUser, QString(mode));
                         }
                         else
-                            channel->removeUserMode(ircUser, QString(modes[c]));
+                            channel->removeUserMode(ircUser, QString(mode));
                     }
                 }
                 else {
@@ -364,7 +510,7 @@ void CoreSessionEventProcessor::processIrcEventMode(IrcEvent *e)
             else {
                 // regular channel modes
                 QString value;
-                Network::ChannelModeType modeType = e->network()->channelModeType(modes[c]);
+                Network::ChannelModeType modeType = e->network()->channelModeType(mode);
                 if (modeType == Network::A_CHANMODE || modeType == Network::B_CHANMODE || (modeType == Network::C_CHANMODE && add)) {
                     if (paramOffset < e->params().count()) {
                         value = e->params()[paramOffset];
@@ -376,15 +522,15 @@ void CoreSessionEventProcessor::processIrcEventMode(IrcEvent *e)
                 }
 
                 if (add)
-                    channel->addChannelMode(modes[c], value);
+                    channel->addChannelMode(mode, value);
                 else
-                    channel->removeChannelMode(modes[c], value);
+                    channel->removeChannelMode(mode, value);
             }
         }
     }
     else {
         // pure User Modes
-        IrcUser *ircUser = e->network()->newIrcUser(e->params().first());
+        IrcUserircUser = e->network()->newIrcUser(e->params().first());
         QString modeString(e->params()[1]);
         QString addModes;
         QString removeModes;
@@ -409,16 +555,35 @@ void CoreSessionEventProcessor::processIrcEventMode(IrcEvent *e)
             ircUser->removeUserModes(removeModes);
 
         if (e->network()->isMe(ircUser)) {
+            // Mark the message as Self
+            e->setFlag(EventManager::Self);
             coreNetwork(e)->updatePersistentModes(addModes, removeModes);
         }
     }
 }
 
+void CoreSessionEventProcessor::processIrcEventNick(IrcEvent* e)
+{
+    if (checkParamCount(e, 1)) {
+        IrcUser* ircuser = e->network()->updateNickFromMask(e->prefix());
+        if (!ircuser) {
+            qWarning() << Q_FUNC_INFO << "Unknown IrcUser!";
+            return;
+        }
+
+        if (e->network()->isMe(ircuser)) {
+            // Mark the message as Self
+            e->setFlag(EventManager::Self);
+        }
+
+        // Actual processing is handled in lateProcessIrcEventNick(), this just sets the event flag
+    }
+}
 
-void CoreSessionEventProcessor::lateProcessIrcEventNick(IrcEvent *e)
+void CoreSessionEventProcessor::lateProcessIrcEventNick(IrcEvente)
 {
     if (checkParamCount(e, 1)) {
-        IrcUser *ircuser = e->network()->updateNickFromMask(e->prefix());
+        IrcUserircuser = e->network()->updateNickFromMask(e->prefix());
         if (!ircuser) {
             qWarning() << Q_FUNC_INFO << "Unknown IrcUser!";
             return;
@@ -434,66 +599,143 @@ void CoreSessionEventProcessor::lateProcessIrcEventNick(IrcEvent *e)
     }
 }
 
+void CoreSessionEventProcessor::processIrcEventPart(IrcEvent* e)
+{
+    if (checkParamCount(e, 1)) {
+        IrcUser* ircuser = e->network()->updateNickFromMask(e->prefix());
+        if (!ircuser) {
+            qWarning() << Q_FUNC_INFO << "Unknown IrcUser!";
+            return;
+        }
+
+        if (e->network()->isMe(ircuser)) {
+            // Mark the message as Self
+            e->setFlag(EventManager::Self);
+        }
+
+        // Actual processing is handled in lateProcessIrcEventNick(), this just sets the event flag
+    }
+}
 
-void CoreSessionEventProcessor::lateProcessIrcEventPart(IrcEvent *e)
+void CoreSessionEventProcessor::lateProcessIrcEventPart(IrcEvente)
 {
     if (checkParamCount(e, 1)) {
-        IrcUser *ircuser = e->network()->updateNickFromMask(e->prefix());
+        IrcUserircuser = e->network()->updateNickFromMask(e->prefix());
         if (!ircuser) {
-            qWarning() << Q_FUNC_INFO<< "Unknown IrcUser!";
+            qWarning() << Q_FUNC_INFO << "Unknown IrcUser!";
             return;
         }
         QString channel = e->params().at(0);
         ircuser->partChannel(channel);
-        if (e->network()->isMe(ircuser))
-            qobject_cast<CoreNetwork *>(e->network())->setChannelParted(channel);
+        if (e->network()->isMe(ircuser)) {
+            qobject_cast<CoreNetwork*>(e->network())->setChannelParted(channel);
+        }
     }
 }
 
-
-void CoreSessionEventProcessor::processIrcEventPing(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventPing(IrcEvent* e)
 {
     QString param = e->params().count() ? e->params().first() : QString();
     // FIXME use events
-    coreNetwork(e)->putRawLine("PONG " + coreNetwork(e)->serverEncode(param));
+    // Take priority so this won't get stuck behind other queued messages.
+    coreNetwork(e)->putRawLine("PONG " + coreNetwork(e)->serverEncode(param), true);
 }
 
-
-void CoreSessionEventProcessor::processIrcEventPong(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventPong(IrcEvent* e)
 {
-    // the server is supposed to send back what we passed as param. and we send a timestamp
-    // but using quote and whatnought one can send arbitrary pings, so we have to do some sanity checks
-    if (checkParamCount(e, 2)) {
-        QString timestamp = e->params().at(1);
-        QTime sendTime = QTime::fromString(timestamp, "hh:mm:ss.zzz");
-        if (sendTime.isValid())
-            e->network()->setLatency(sendTime.msecsTo(QTime::currentTime()) / 2);
+    // Ensure we get at least one parameter
+    if (!checkParamCount(e, 1))
+        return;
+
+    // Some IRC servers respond with only one parameter, others respond with two, with the latter
+    // being the text sent.  Handle both situations.
+    QString timestamp;
+    if (e->params().count() < 2) {
+        // Only one parameter received
+        // :localhost PONG 02:43:49.565
+        timestamp = e->params().at(0);
     }
-}
+    else {
+        // Two parameters received, pick the second
+        // :localhost PONG localhost :02:43:49.565
+        timestamp = e->params().at(1);
+    }
+
+    // The server is supposed to send back what we passed as parameter, and we send a timestamp.
+    // However, using quote and whatnot, one can send arbitrary pings, and IRC servers may decide to
+    // ignore our requests entirely and send whatever they want, so we have to do some sanity
+    // checks.
+    //
+    // Attempt to parse the timestamp
+    QTime sendTime = QTime::fromString(timestamp, "hh:mm:ss.zzz");
+    if (sendTime.isValid()) {
+        // Mark IRC server as sending valid ping replies
+        if (!coreNetwork(e)->isPongTimestampValid()) {
+            coreNetwork(e)->setPongTimestampValid(true);
+            // Add a message the first time it happens
+            qDebug().nospace() << "Received PONG with valid timestamp, marking pong replies on "
+                                  "network "
+                               << "\"" << qPrintable(e->network()->networkName())
+                               << "\" (ID: " << qPrintable(QString::number(e->network()->networkId().toInt()))
+                               << ") as usable for latency measurement";
+        }
+        // Remove pending flag
+        coreNetwork(e)->resetPongReplyPending();
+
+        // Don't show this in the UI
+        e->setFlag(EventManager::Silent);
+        // TODO:  To allow for a user-sent /ping (without arguments, so default timestamp is used),
+        // this could track how many automated PINGs have been sent by the core and subtract one
+        // each time, only marking the PING as silent if there's pending automated pong replies.
+        // However, that's a behavior change which warrants further testing.  For now, take the
+        // simpler, previous approach that errs on the side of silencing too much.
+
+        // Calculate latency from time difference, divided by 2 to account for round-trip time
+        e->network()->setLatency(sendTime.msecsTo(QTime::currentTime()) / 2);
+    }
+    else if (coreNetwork(e)->isPongReplyPending() && !coreNetwork(e)->isPongTimestampValid()) {
+        // There's an auto-PING reply pending and we've not yet received a PONG reply with a valid
+        // timestamp.  It's possible this server will never respond with a valid timestamp, and thus
+        // any automated PINGs will result in unwanted spamming of the server buffer.
 
+        // Don't show this in the UI
+        e->setFlag(EventManager::Silent);
+        // Remove pending flag
+        coreNetwork(e)->resetPongReplyPending();
+
+        // Log a message
+        qDebug().nospace() << "Received PONG with invalid timestamp from network "
+                           << "\"" << qPrintable(e->network()->networkName())
+                           << "\" (ID: " << qPrintable(QString::number(e->network()->networkId().toInt()))
+                           << "), silencing, parameters are " << e->params();
+    }
+    // else: We're not expecting a PONG reply and timestamp is not valid, assume it's from the user
+}
 
-void CoreSessionEventProcessor::processIrcEventQuit(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventQuit(IrcEvente)
 {
-    IrcUser *ircuser = e->network()->updateNickFromMask(e->prefix());
+    IrcUserircuser = e->network()->updateNickFromMask(e->prefix());
     if (!ircuser)
         return;
 
+    if (e->network()->isMe(ircuser)) {
+        // Mark the message as Self
+        e->setFlag(EventManager::Self);
+    }
+
     QString msg;
     if (e->params().count() > 0)
         msg = e->params()[0];
 
     // check if netsplit
     if (Netsplit::isNetsplit(msg)) {
-        Netsplit *n;
+        Netsplitn;
         if (!_netsplits[e->network()].contains(msg)) {
             n = new Netsplit(e->network(), this);
-            connect(n, SIGNAL(finished()), this, SLOT(handleNetsplitFinished()));
-            connect(n, SIGNAL(netsplitJoin(Network*, QString, QStringList, QStringList, QString)),
-                this, SLOT(handleNetsplitJoin(Network*, QString, QStringList, QStringList, QString)));
-            connect(n, SIGNAL(netsplitQuit(Network*, QString, QStringList, QString)),
-                this, SLOT(handleNetsplitQuit(Network*, QString, QStringList, QString)));
-            connect(n, SIGNAL(earlyJoin(Network*, QString, QStringList, QStringList)),
-                this, SLOT(handleEarlyNetsplitJoin(Network*, QString, QStringList, QStringList)));
+            connect(n, &Netsplit::finished, this, &CoreSessionEventProcessor::handleNetsplitFinished);
+            connect(n, &Netsplit::netsplitJoin, this, &CoreSessionEventProcessor::handleNetsplitJoin);
+            connect(n, &Netsplit::netsplitQuit, this, &CoreSessionEventProcessor::handleNetsplitQuit);
+            connect(n, &Netsplit::earlyJoin, this, &CoreSessionEventProcessor::handleEarlyNetsplitJoin);
             _netsplits[e->network()].insert(msg, n);
         }
         else {
@@ -506,78 +748,127 @@ void CoreSessionEventProcessor::processIrcEventQuit(IrcEvent *e)
     // normal quit is handled in lateProcessIrcEventQuit()
 }
 
-
-void CoreSessionEventProcessor::lateProcessIrcEventQuit(IrcEvent *e)
+void CoreSessionEventProcessor::lateProcessIrcEventQuit(IrcEvent* e)
 {
     if (e->testFlag(EventManager::Netsplit))
         return;
 
-    IrcUser *ircuser = e->network()->updateNickFromMask(e->prefix());
+    IrcUserircuser = e->network()->updateNickFromMask(e->prefix());
     if (!ircuser)
         return;
 
     ircuser->quit();
 }
 
-
-void CoreSessionEventProcessor::processIrcEventTopic(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEventTopic(IrcEvent* e)
 {
     if (checkParamCount(e, 2)) {
-        e->network()->updateNickFromMask(e->prefix());
-        IrcChannel *channel = e->network()->ircChannel(e->params().at(0));
+        IrcUser* ircuser = e->network()->updateNickFromMask(e->prefix());
+
+        if (e->network()->isMe(ircuser)) {
+            // Mark the message as Self
+            e->setFlag(EventManager::Self);
+        }
+
+        IrcChannel* channel = e->network()->ircChannel(e->params().at(0));
         if (channel)
             channel->setTopic(e->params().at(1));
     }
 }
 
+/* ERROR - "ERROR :reason"
+Example:  ERROR :Closing Link: nickname[xxx.xxx.xxx.xxx] (Large base64 image paste.)
+See https://tools.ietf.org/html/rfc2812#section-3.7.4 */
+void CoreSessionEventProcessor::processIrcEventError(IrcEvent* e)
+{
+    if (!checkParamCount(e, 1))
+        return;
+
+    if (coreNetwork(e)->disconnectExpected()) {
+        // During QUIT, the server should send an error (often, but not always, "Closing Link"). As
+        // we're expecting it, don't show this to the user.
+        e->setFlag(EventManager::Silent);
+    }
+}
 
 #ifdef HAVE_QCA2
-void CoreSessionEventProcessor::processKeyEvent(KeyEvent *e)
+void CoreSessionEventProcessor::processKeyEvent(KeyEvente)
 {
     if (!Cipher::neededFeaturesAvailable()) {
-        emit newEvent(new MessageEvent(Message::Error, e->network(), tr("Unable to perform key exchange, missing qca-ossl plugin."), e->prefix(), e->target(), Message::None, e->timestamp()));
+        emit newEvent(new MessageEvent(Message::Error,
+                                       e->network(),
+                                       tr("Unable to perform key exchange, missing qca-ossl plugin."),
+                                       e->prefix(),
+                                       e->target(),
+                                       Message::None,
+                                       e->timestamp()));
         return;
     }
-    CoreNetwork *net = qobject_cast<CoreNetwork*>(e->network());
-    Cipher *c = net->cipher(e->target());
-    if (!c) // happens when there is no CoreIrcChannel for the target (i.e. never?)
+    auto* net = qobject_cast<CoreNetwork*>(e->network());
+    Cipherc = net->cipher(e->target());
+    if (!c)  // happens when there is no CoreIrcChannel for the target (i.e. never?)
         return;
 
     if (e->exchangeType() == KeyEvent::Init) {
         QByteArray pubKey = c->parseInitKeyX(e->key());
         if (pubKey.isEmpty()) {
-            emit newEvent(new MessageEvent(Message::Error, e->network(), tr("Unable to parse the DH1080_INIT. Key exchange failed."), e->prefix(), e->target(), Message::None, e->timestamp()));
+            emit newEvent(new MessageEvent(Message::Error,
+                                           e->network(),
+                                           tr("Unable to parse the DH1080_INIT. Key exchange failed."),
+                                           e->prefix(),
+                                           e->target(),
+                                           Message::None,
+                                           e->timestamp()));
             return;
-        } else {
+        }
+        else {
             net->setCipherKey(e->target(), c->key());
-            emit newEvent(new MessageEvent(Message::Info, e->network(), tr("Your key is set and messages will be encrypted."), e->prefix(), e->target(), Message::None, e->timestamp()));
+            emit newEvent(new MessageEvent(Message::Info,
+                                           e->network(),
+                                           tr("Your key is set and messages will be encrypted."),
+                                           e->prefix(),
+                                           e->target(),
+                                           Message::None,
+                                           e->timestamp()));
             QList<QByteArray> p;
-            p << net->serverEncode(e->target()) << net->serverEncode("DH1080_FINISH ")+pubKey;
+            p << net->serverEncode(e->target()) << net->serverEncode("DH1080_FINISH ") + pubKey;
             net->putCmd("NOTICE", p);
         }
-    } else {
+    }
+    else {
         if (c->parseFinishKeyX(e->key())) {
             net->setCipherKey(e->target(), c->key());
-            emit newEvent(new MessageEvent(Message::Info, e->network(), tr("Your key is set and messages will be encrypted."), e->prefix(), e->target(), Message::None, e->timestamp()));
-        } else {
-            emit newEvent(new MessageEvent(Message::Info, e->network(), tr("Failed to parse DH1080_FINISH. Key exchange failed."), e->prefix(), e->target(), Message::None, e->timestamp()));
+            emit newEvent(new MessageEvent(Message::Info,
+                                           e->network(),
+                                           tr("Your key is set and messages will be encrypted."),
+                                           e->prefix(),
+                                           e->target(),
+                                           Message::None,
+                                           e->timestamp()));
+        }
+        else {
+            emit newEvent(new MessageEvent(Message::Info,
+                                           e->network(),
+                                           tr("Failed to parse DH1080_FINISH. Key exchange failed."),
+                                           e->prefix(),
+                                           e->target(),
+                                           Message::None,
+                                           e->timestamp()));
         }
     }
 }
 #endif
 
-
 /* RPL_WELCOME */
-void CoreSessionEventProcessor::processIrcEvent001(IrcEventNumeric *e)
+void CoreSessionEventProcessor::processIrcEvent001(IrcEventNumerice)
 {
     e->network()->setCurrentServer(e->prefix());
     e->network()->setMyNick(e->target());
 }
 
-
 /* RPL_ISUPPORT */
 // TODO Complete 005 handling, also use sensible defaults for non-sent stuff
-void CoreSessionEventProcessor::processIrcEvent005(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent005(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -593,35 +884,30 @@ void CoreSessionEventProcessor::processIrcEvent005(IrcEvent *e)
     e->network()->determinePrefixes();
 }
 
-
 /* RPL_UMODEIS - "<user_modes> [<user_mode_params>]" */
-void CoreSessionEventProcessor::processIrcEvent221(IrcEvent *)
+void CoreSessionEventProcessor::processIrcEvent221(IrcEvent*)
 {
     // TODO: save information in network object
 }
 
-
 /* RPL_STATSCONN - "Highest connection cout: 8000 (7999 clients)" */
-void CoreSessionEventProcessor::processIrcEvent250(IrcEvent *)
+void CoreSessionEventProcessor::processIrcEvent250(IrcEvent*)
 {
     // TODO: save information in network object
 }
 
-
 /* RPL_LOCALUSERS - "Current local user: 5024  Max: 7999 */
-void CoreSessionEventProcessor::processIrcEvent265(IrcEvent *)
+void CoreSessionEventProcessor::processIrcEvent265(IrcEvent*)
 {
     // TODO: save information in network object
 }
 
-
 /* RPL_GLOBALUSERS - "Current global users: 46093  Max: 47650" */
-void CoreSessionEventProcessor::processIrcEvent266(IrcEvent *)
+void CoreSessionEventProcessor::processIrcEvent266(IrcEvent*)
 {
     // TODO: save information in network object
 }
 
-
 /*
 WHOIS-Message:
    Replies 311 - 313, 317 - 319 are all replies generated in response to a WHOIS message.
@@ -636,24 +922,25 @@ WHOWAS-Message:
 */
 
 /* RPL_AWAY - "<nick> :<away message>" */
-void CoreSessionEventProcessor::processIrcEvent301(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent301(IrcEvente)
 {
     if (!checkParamCount(e, 2))
         return;
 
-    IrcUser *ircuser = e->network()->ircUser(e->params().at(0));
+    IrcUserircuser = e->network()->ircUser(e->params().at(0));
     if (ircuser) {
         ircuser->setAway(true);
         ircuser->setAwayMessage(e->params().at(1));
-        //ircuser->setLastAwayMessage(now);
+        // lastAwayMessageTime is set in EventStringifier::processIrcEvent301(), no need to set it
+        // here too
+        // ircuser->setLastAwayMessageTime(now);
     }
 }
 
-
 /* RPL_UNAWAY - ":You are no longer marked as being away" */
-void CoreSessionEventProcessor::processIrcEvent305(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent305(IrcEvente)
 {
-    IrcUser *me = e->network()->me();
+    IrcUserme = e->network()->me();
     if (me)
         me->setAway(false);
 
@@ -663,47 +950,43 @@ void CoreSessionEventProcessor::processIrcEvent305(IrcEvent *e)
     }
 }
 
-
 /* RPL_NOWAWAY - ":You have been marked as being away" */
-void CoreSessionEventProcessor::processIrcEvent306(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent306(IrcEvente)
 {
-    IrcUser *me = e->network()->me();
+    IrcUserme = e->network()->me();
     if (me)
         me->setAway(true);
 }
 
-
 /* RPL_WHOISSERVICE - "<user> is registered nick" */
-void CoreSessionEventProcessor::processIrcEvent307(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent307(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
 
-    IrcUser *ircuser = e->network()->ircUser(e->params().at(0));
+    IrcUserircuser = e->network()->ircUser(e->params().at(0));
     if (ircuser)
         ircuser->setWhoisServiceReply(e->params().join(" "));
 }
 
-
 /* RPL_SUSERHOST - "<user> is available for help." */
-void CoreSessionEventProcessor::processIrcEvent310(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent310(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
 
-    IrcUser *ircuser = e->network()->ircUser(e->params().at(0));
+    IrcUserircuser = e->network()->ircUser(e->params().at(0));
     if (ircuser)
         ircuser->setSuserHost(e->params().join(" "));
 }
 
-
 /*  RPL_WHOISUSER - "<nick> <user> <host> * :<real name>" */
-void CoreSessionEventProcessor::processIrcEvent311(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent311(IrcEvente)
 {
     if (!checkParamCount(e, 3))
         return;
 
-    IrcUser *ircuser = e->network()->ircUser(e->params().at(0));
+    IrcUserircuser = e->network()->ircUser(e->params().at(0));
     if (ircuser) {
         ircuser->setUser(e->params().at(1));
         ircuser->setHost(e->params().at(2));
@@ -711,33 +994,30 @@ void CoreSessionEventProcessor::processIrcEvent311(IrcEvent *e)
     }
 }
 
-
 /*  RPL_WHOISSERVER -  "<nick> <server> :<server info>" */
-void CoreSessionEventProcessor::processIrcEvent312(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent312(IrcEvente)
 {
     if (!checkParamCount(e, 2))
         return;
 
-    IrcUser *ircuser = e->network()->ircUser(e->params().at(0));
+    IrcUserircuser = e->network()->ircUser(e->params().at(0));
     if (ircuser)
         ircuser->setServer(e->params().at(1));
 }
 
-
 /*  RPL_WHOISOPERATOR - "<nick> :is an IRC operator" */
-void CoreSessionEventProcessor::processIrcEvent313(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent313(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
 
-    IrcUser *ircuser = e->network()->ircUser(e->params().at(0));
+    IrcUserircuser = e->network()->ircUser(e->params().at(0));
     if (ircuser)
         ircuser->setIrcOperator(e->params().last());
 }
 
-
 /*  RPL_ENDOFWHO: "<name> :End of WHO list" */
-void CoreSessionEventProcessor::processIrcEvent315(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent315(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -746,10 +1026,9 @@ void CoreSessionEventProcessor::processIrcEvent315(IrcEvent *e)
         e->setFlag(EventManager::Silent);
 }
 
-
 /*  RPL_WHOISIDLE - "<nick> <integer> :seconds idle"
    (real life: "<nick> <integer> <integer> :seconds idle, signon time) */
-void CoreSessionEventProcessor::processIrcEvent317(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent317(IrcEvente)
 {
     if (!checkParamCount(e, 2))
         return;
@@ -757,12 +1036,22 @@ void CoreSessionEventProcessor::processIrcEvent317(IrcEvent *e)
     QDateTime loginTime;
 
     int idleSecs = e->params()[1].toInt();
-    if (e->params().count() > 3) { // if we have more then 3 params we have the above mentioned "real life" situation
-        int logintime = e->params()[2].toInt();
-        loginTime = QDateTime::fromTime_t(logintime);
+    if (e->params().count() > 3) {  // if we have more then 3 params we have the above mentioned "real life" situation
+        // Allow for 64-bit time
+        qint64 logintime = e->params()[2].toLongLong();
+        // Time in IRC protocol is defined as seconds.  Convert from seconds instead.
+        // See https://doc.qt.io/qt-5/qdatetime.html#fromSecsSinceEpoch
+#if QT_VERSION >= 0x050800
+        loginTime = QDateTime::fromSecsSinceEpoch(logintime);
+#else
+        // fromSecsSinceEpoch() was added in Qt 5.8.  Manually downconvert to seconds for
+        // now.
+        // See https://doc.qt.io/qt-5/qdatetime.html#fromMSecsSinceEpoch
+        loginTime = QDateTime::fromMSecsSinceEpoch((qint64)(logintime * 1000));
+#endif
     }
 
-    IrcUser *ircuser = e->network()->ircUser(e->params()[0]);
+    IrcUserircuser = e->network()->ircUser(e->params()[0]);
     if (ircuser) {
         ircuser->setIdleTime(e->timestamp().addSecs(-idleSecs));
         if (loginTime.isValid())
@@ -770,9 +1059,8 @@ void CoreSessionEventProcessor::processIrcEvent317(IrcEvent *e)
     }
 }
 
-
 /* RPL_LIST -  "<channel> <# visible> :<topic>" */
-void CoreSessionEventProcessor::processIrcEvent322(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent322(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -784,10 +1072,13 @@ void CoreSessionEventProcessor::processIrcEvent322(IrcEvent *e)
     switch (e->params().count()) {
     case 3:
         topic = e->params()[2];
+        // fallthrough
     case 2:
         userCount = e->params()[1].toUInt();
+        // fallthrough
     case 1:
         channelName = e->params()[0];
+        // fallthrough
     default:
         break;
     }
@@ -795,9 +1086,8 @@ void CoreSessionEventProcessor::processIrcEvent322(IrcEvent *e)
         e->stop();  // consumed by IrcListHelper, so don't further process/show this event
 }
 
-
 /* RPL_LISTEND ":End of LIST" */
-void CoreSessionEventProcessor::processIrcEvent323(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent323(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -806,64 +1096,81 @@ void CoreSessionEventProcessor::processIrcEvent323(IrcEvent *e)
         e->stop();  // consumed by IrcListHelper, so don't further process/show this event
 }
 
-
 /* RPL_CHANNELMODEIS - "<channel> <mode> <mode params>" */
-void CoreSessionEventProcessor::processIrcEvent324(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent324(IrcEvente)
 {
     processIrcEventMode(e);
 }
 
+/*  RPL_WHOISACCOUNT - "<nick> <account> :is authed as" */
+void CoreSessionEventProcessor::processIrcEvent330(IrcEvent* e)
+{
+    // Though the ":is authed as" remark should always be there, we should handle cases when it's
+    // not included, too.
+    if (!checkParamCount(e, 2))
+        return;
+
+    IrcUser* ircuser = e->network()->ircUser(e->params().at(0));
+    if (ircuser) {
+        ircuser->setAccount(e->params().at(1));
+    }
+}
 
 /* RPL_NOTOPIC */
-void CoreSessionEventProcessor::processIrcEvent331(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent331(IrcEvente)
 {
     if (!checkParamCount(e, 1))
         return;
 
-    IrcChannel *chan = e->network()->ircChannel(e->params()[0]);
+    IrcChannelchan = e->network()->ircChannel(e->params()[0]);
     if (chan)
         chan->setTopic(QString());
 }
 
-
 /* RPL_TOPIC */
-void CoreSessionEventProcessor::processIrcEvent332(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent332(IrcEvente)
 {
     if (!checkParamCount(e, 2))
         return;
 
-    IrcChannel *chan = e->network()->ircChannel(e->params()[0]);
+    IrcChannelchan = e->network()->ircChannel(e->params()[0]);
     if (chan)
         chan->setTopic(e->params()[1]);
 }
 
-
 /*  RPL_WHOREPLY: "<channel> <user> <host> <server> <nick>
               ( "H" / "G" > ["*"] [ ( "@" / "+" ) ] :<hopcount> <real name>" */
-void CoreSessionEventProcessor::processIrcEvent352(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent352(IrcEvente)
 {
     if (!checkParamCount(e, 6))
         return;
 
     QString channel = e->params()[0];
-    IrcUser *ircuser = e->network()->ircUser(e->params()[4]);
+    IrcUserircuser = e->network()->ircUser(e->params()[4]);
     if (ircuser) {
-        ircuser->setUser(e->params()[1]);
-        ircuser->setHost(e->params()[2]);
-
-        bool away = e->params()[5].startsWith("G");
-        ircuser->setAway(away);
-        ircuser->setServer(e->params()[3]);
-        ircuser->setRealName(e->params().last().section(" ", 1));
+        // Only process the WHO information if an IRC user exists.  Don't create an IRC user here;
+        // there's no way to track when the user quits, which would leave a phantom IrcUser lying
+        // around.
+        // NOTE:  Whenever MONITOR support is introduced, the IrcUser will be created by an
+        // RPL_MONONLINE numeric before any WHO commands are run.
+        processWhoInformation(e->network(),
+                              channel,
+                              ircuser,
+                              e->params()[3],
+                              e->params()[1],
+                              e->params()[2],
+                              e->params()[5],
+                              e->params().last().section(" ", 1));
     }
 
-    if (coreNetwork(e)->isAutoWhoInProgress(channel))
+    // Check if channel name has a who in progress.
+    if (coreNetwork(e)->isAutoWhoInProgress(channel)) {
         e->setFlag(EventManager::Silent);
+    }
 }
 
-
 /* RPL_NAMREPLY */
-void CoreSessionEventProcessor::processIrcEvent353(IrcEvent *e)
+void CoreSessionEventProcessor::processIrcEvent353(IrcEvente)
 {
     if (!checkParamCount(e, 3))
         return;
@@ -872,7 +1179,7 @@ void CoreSessionEventProcessor::processIrcEvent353(IrcEvent *e)
     // we don't use this information at the time beeing
     QString channelname = e->params()[1];
 
-    IrcChannel *channel = e->network()->ircChannel(channelname);
+    IrcChannelchannel = e->network()->ircChannel(channelname);
     if (!channel) {
         qWarning() << Q_FUNC_INFO << "Received unknown target channel:" << channelname;
         return;
@@ -881,14 +1188,36 @@ void CoreSessionEventProcessor::processIrcEvent353(IrcEvent *e)
     QStringList nicks;
     QStringList modes;
 
-    foreach(QString nick, e->params()[2].split(' ', QString::SkipEmptyParts)) {
+    // Cache result of multi-prefix to avoid unneeded casts and lookups with each iteration.
+    bool _useCapMultiPrefix = coreNetwork(e)->capEnabled(IrcCap::MULTI_PREFIX);
+
+    for (QString nick : e->params()[2].split(' ', QString::SkipEmptyParts)) {
         QString mode;
 
-        if (e->network()->prefixes().contains(nick[0])) {
+        if (_useCapMultiPrefix) {
+            // If multi-prefix is enabled, all modes will be sent in NAMES replies.
+            // :hades.arpa 353 guest = #tethys :~&@%+aji &@Attila @+alyx +KindOne Argure
+            // See: http://ircv3.net/specs/extensions/multi-prefix-3.1.html
+            while (e->network()->prefixes().contains(nick[0])) {
+                // Mode found in 1 left-most character, add it to the list.
+                // Note: sending multiple modes may cause a warning in older clients.
+                // In testing, the clients still seemed to function fine.
+                mode.append(e->network()->prefixToMode(nick[0]));
+                // Remove this mode from the nick
+                nick = nick.remove(0, 1);
+            }
+        }
+        else if (e->network()->prefixes().contains(nick[0])) {
+            // Multi-prefix is disabled and a mode prefix was found.
             mode = e->network()->prefixToMode(nick[0]);
             nick = nick.mid(1);
         }
 
+        // If userhost-in-names capability is enabled, the following will be
+        // in the form "nick!user@host" rather than "nick".  This works without
+        // special handling as the following use nickFromHost() as needed.
+        // See: http://ircv3.net/specs/extensions/userhost-in-names-3.2.html
+
         nicks << nick;
         modes << mode;
     }
@@ -896,9 +1225,135 @@ void CoreSessionEventProcessor::processIrcEvent353(IrcEvent *e)
     channel->joinIrcUsers(nicks, modes);
 }
 
+/*  RPL_WHOSPCRPL: "<yournick> 152 #<channel> ~<ident> <host> <servname> <nick>
+                    ("H"/ "G") <account> :<realname>"
+<channel> is * if not specific to any channel
+<account> is * if not logged in
+Follows HexChat's usage of 'whox'
+See https://github.com/hexchat/hexchat/blob/c874a9525c9b66f1d5ddcf6c4107d046eba7e2c5/src/common/proto-irc.c#L750
+And http://faerion.sourceforge.net/doc/irc/whox.var*/
+void CoreSessionEventProcessor::processIrcEvent354(IrcEvent* e)
+{
+    // First only check if at least one parameter exists.  Otherwise, it'll stop the result from
+    // being shown if the user chooses different parameters.
+    if (!checkParamCount(e, 1))
+        return;
+
+    if (e->params()[0].toUInt() != IrcCap::ACCOUNT_NOTIFY_WHOX_NUM) {
+        // Ignore WHOX replies without expected number for we have no idea what fields are specified
+        return;
+    }
+
+    // Now we're fairly certain this is supposed to be an automated WHOX.  Bail out if it doesn't
+    // match what we require - 9 parameters.
+    if (!checkParamCount(e, 9))
+        return;
+
+    QString channel = e->params()[1];
+    IrcUser* ircuser = e->network()->ircUser(e->params()[5]);
+    if (ircuser) {
+        // Only process the WHO information if an IRC user exists.  Don't create an IRC user here;
+        // there's no way to track when the user quits, which would leave a phantom IrcUser lying
+        // around.
+        // NOTE:  Whenever MONITOR support is introduced, the IrcUser will be created by an
+        // RPL_MONONLINE numeric before any WHO commands are run.
+        processWhoInformation(e->network(), channel, ircuser, e->params()[4], e->params()[2], e->params()[3], e->params()[6], e->params().last());
+        // Don't use .section(" ", 1) with WHOX replies, for there's no hopcount to trim out
+
+        // As part of IRCv3 account-notify, check account name
+        // WHOX uses '0' to indicate logged-out, account-notify and extended-join uses '*'.
+        QString newAccount = e->params()[7];
+        if (newAccount != "0") {
+            // Account logged in, set account name
+            ircuser->setAccount(newAccount);
+        }
+        else {
+            // Account logged out, set account name to logged-out
+            ircuser->setAccount("*");
+        }
+    }
+
+    // Check if channel name has a who in progress.
+    if (coreNetwork(e)->isAutoWhoInProgress(channel)) {
+        e->setFlag(EventManager::Silent);
+    }
+}
+
+void CoreSessionEventProcessor::processWhoInformation(Network* net,
+                                                      const QString& targetChannel,
+                                                      IrcUser* ircUser,
+                                                      const QString& server,
+                                                      const QString& user,
+                                                      const QString& host,
+                                                      const QString& awayStateAndModes,
+                                                      const QString& realname)
+{
+    ircUser->setUser(user);
+    ircUser->setHost(host);
+    ircUser->setServer(server);
+    ircUser->setRealName(realname);
+
+    bool away = awayStateAndModes.contains("G", Qt::CaseInsensitive);
+    ircUser->setAway(away);
+
+    if (net->capEnabled(IrcCap::MULTI_PREFIX)) {
+        // If multi-prefix is enabled, all modes will be sent in WHO replies.
+        // :kenny.chatspike.net 352 guest #test grawity broken.symlink *.chatspike.net grawity H@%+ :0 Mantas M.
+        // See: http://ircv3.net/specs/extensions/multi-prefix-3.1.html
+        QString uncheckedModes = awayStateAndModes;
+        QString validModes = QString();
+        while (!uncheckedModes.isEmpty()) {
+            // Mode found in 1 left-most character, add it to the list
+            if (net->prefixes().contains(uncheckedModes[0])) {
+                validModes.append(net->prefixToMode(uncheckedModes[0]));
+            }
+            // Remove this mode from the list of unchecked modes
+            uncheckedModes = uncheckedModes.remove(0, 1);
+        }
+
+        // Some IRC servers decide to not follow the spec, returning only -some- of the user
+        // modes in WHO despite listing them all in NAMES.  For now, assume it can only add
+        // and not take away.  *sigh*
+        if (!validModes.isEmpty()) {
+            if (targetChannel != "*") {
+                // Channel-specific modes received, apply to given channel only
+                IrcChannel* ircChan = net->ircChannel(targetChannel);
+                if (ircChan) {
+                    // Do one mode at a time
+                    // TODO Better way of syncing this without breaking protocol?
+                    for (int i = 0; i < validModes.count(); ++i) {
+                        ircChan->addUserMode(ircUser, validModes.at(i));
+                    }
+                }
+            }
+            else {
+                // Modes apply to the user everywhere
+                ircUser->addUserModes(validModes);
+            }
+        }
+    }
+}
+
+/* ERR_NOSUCHCHANNEL - "<channel name> :No such channel" */
+void CoreSessionEventProcessor::processIrcEvent403(IrcEventNumeric* e)
+{
+    // If this is the result of an AutoWho, hide it.  It's confusing to show to the user.
+    // Though the ":No such channel" remark should always be there, we should handle cases when it's
+    // not included, too.
+    if (!checkParamCount(e, 1))
+        return;
+
+    QString channelOrNick = e->params()[0];
+    // Check if channel name has a who in progress.
+    // If not, then check if user nick exists and has a who in progress.
+    if (coreNetwork(e)->isAutoWhoInProgress(channelOrNick)) {
+        qDebug() << "Channel/nick" << channelOrNick << "no longer exists during AutoWho, ignoring";
+        e->setFlag(EventManager::Silent);
+    }
+}
 
 /* ERR_ERRONEUSNICKNAME */
-void CoreSessionEventProcessor::processIrcEvent432(IrcEventNumeric *e)
+void CoreSessionEventProcessor::processIrcEvent432(IrcEventNumerice)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -918,9 +1373,8 @@ void CoreSessionEventProcessor::processIrcEvent432(IrcEventNumeric *e)
     tryNextNick(e, errnick, true /* erroneus */);
 }
 
-
 /* ERR_NICKNAMEINUSE */
-void CoreSessionEventProcessor::processIrcEvent433(IrcEventNumeric *e)
+void CoreSessionEventProcessor::processIrcEvent433(IrcEventNumerice)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -935,9 +1389,8 @@ void CoreSessionEventProcessor::processIrcEvent433(IrcEventNumeric *e)
     tryNextNick(e, errnick);
 }
 
-
 /* ERR_UNAVAILRESOURCE */
-void CoreSessionEventProcessor::processIrcEvent437(IrcEventNumeric *e)
+void CoreSessionEventProcessor::processIrcEvent437(IrcEventNumerice)
 {
     if (!checkParamCount(e, 1))
         return;
@@ -953,7 +1406,6 @@ void CoreSessionEventProcessor::processIrcEvent437(IrcEventNumeric *e)
         tryNextNick(e, errnick);
 }
 
-
 /* template
 void CoreSessionEventProcessor::processIrcEvent(IrcEvent *e) {
   if(!checkParamCount(e, 1))
@@ -964,25 +1416,22 @@ void CoreSessionEventProcessor::processIrcEvent(IrcEvent *e) {
 
 /* Handle signals from Netsplit objects  */
 
-void CoreSessionEventProcessor::handleNetsplitJoin(Network *net,
-    const QString &channel,
-    const QStringList &users,
-    const QStringList &modes,
-    const QString &quitMessage)
+void CoreSessionEventProcessor::handleNetsplitJoin(
+    Network* net, const QString& channel, const QStringList& users, const QStringList& modes, const QString& quitMessage)
 {
-    IrcChannel *ircChannel = net->ircChannel(channel);
+    IrcChannelircChannel = net->ircChannel(channel);
     if (!ircChannel) {
         return;
     }
-    QList<IrcUser *> ircUsers;
+    QList<IrcUser*> ircUsers;
     QStringList newModes = modes;
     QStringList newUsers = users;
 
-    foreach(const QString &user, users) {
-        IrcUser *iu = net->ircUser(nickFromMask(user));
+    for (const QString& user : users) {
+        IrcUseriu = net->ircUser(nickFromMask(user));
         if (iu)
             ircUsers.append(iu);
-        else { // the user already quit
+        else {  // the user already quit
             int idx = users.indexOf(user);
             newUsers.removeAt(idx);
             newModes.removeAt(idx);
@@ -990,81 +1439,75 @@ void CoreSessionEventProcessor::handleNetsplitJoin(Network *net,
     }
 
     ircChannel->joinIrcUsers(ircUsers, newModes);
-    NetworkSplitEvent *event = new NetworkSplitEvent(EventManager::NetworkSplitJoin, net, channel, newUsers, quitMessage);
+    NetworkSplitEventevent = new NetworkSplitEvent(EventManager::NetworkSplitJoin, net, channel, newUsers, quitMessage);
     emit newEvent(event);
 }
 
-
-void CoreSessionEventProcessor::handleNetsplitQuit(Network *net, const QString &channel, const QStringList &users, const QString &quitMessage)
+void CoreSessionEventProcessor::handleNetsplitQuit(Network* net, const QString& channel, const QStringList& users, const QString& quitMessage)
 {
-    NetworkSplitEvent *event = new NetworkSplitEvent(EventManager::NetworkSplitQuit, net, channel, users, quitMessage);
+    NetworkSplitEventevent = new NetworkSplitEvent(EventManager::NetworkSplitQuit, net, channel, users, quitMessage);
     emit newEvent(event);
-    foreach(QString user, users) {
-        IrcUser *iu = net->ircUser(nickFromMask(user));
-        if (iu)
-            iu->quit();
+    for (const QString& user : users) {
+        IrcUser* ircUser = net->ircUser(nickFromMask(user));
+        if (ircUser) ircUser->quit();
     }
 }
 
-
-void CoreSessionEventProcessor::handleEarlyNetsplitJoin(Network *net, const QString &channel, const QStringList &users, const QStringList &modes)
+void CoreSessionEventProcessor::handleEarlyNetsplitJoin(Network* net, const QString& channel, const QStringList& users, const QStringList& modes)
 {
-    IrcChannel *ircChannel = net->ircChannel(channel);
+    IrcChannelircChannel = net->ircChannel(channel);
     if (!ircChannel) {
         qDebug() << "handleEarlyNetsplitJoin(): channel " << channel << " invalid";
         return;
     }
-    QList<NetworkEvent *> events;
-    QList<IrcUser *> ircUsers;
+    QList<NetworkEvent*> events;
+    QList<IrcUser*> ircUsers;
     QStringList newModes = modes;
 
-    foreach(QString user, users) {
-        IrcUser *iu = net->updateNickFromMask(user);
-        if (iu) {
-            ircUsers.append(iu);
+    for (const QString& user : users) {
+        IrcUser* ircUser = net->updateNickFromMask(user);
+        if (ircUser) {
+            ircUsers.append(ircUser);
             // fake event for scripts that consume join events
-            events << new IrcEvent(EventManager::IrcEventJoin, net, iu->hostmask(), QStringList() << channel);
+            events << new IrcEvent(EventManager::IrcEventJoin, net, {}, ircUser->hostmask(), QStringList() << channel);
         }
         else {
             newModes.removeAt(users.indexOf(user));
         }
     }
     ircChannel->joinIrcUsers(ircUsers, newModes);
-    foreach(NetworkEvent *event, events) {
-        event->setFlag(EventManager::Fake); // ignore this in here!
+    for (NetworkEvent* event : events) {
+        event->setFlag(EventManager::Fake);  // ignore this in here!
         emit newEvent(event);
     }
 }
 
-
 void CoreSessionEventProcessor::handleNetsplitFinished()
 {
-    Netsplit *n = qobject_cast<Netsplit *>(sender());
+    auto* n = qobject_cast<Netsplit*>(sender());
     Q_ASSERT(n);
-    QHash<QString, Netsplit *> splithash  = _netsplits.take(n->network());
+    QHash<QString, Netsplit*> splithash = _netsplits.take(n->network());
     splithash.remove(splithash.key(n));
     if (splithash.count())
         _netsplits[n->network()] = splithash;
     n->deleteLater();
 }
 
-
 void CoreSessionEventProcessor::destroyNetsplits(NetworkId netId)
 {
-    Network *net = coreSession()->network(netId);
+    Networknet = coreSession()->network(netId);
     if (!net)
         return;
 
-    QHash<QString, Netsplit *> splits = _netsplits.take(net);
+    QHash<QString, Netsplit*> splits = _netsplits.take(net);
     qDeleteAll(splits);
 }
 
-
 /*******************************/
 /******** CTCP HANDLING ********/
 /*******************************/
 
-void CoreSessionEventProcessor::processCtcpEvent(CtcpEvent *e)
+void CoreSessionEventProcessor::processCtcpEvent(CtcpEvente)
 {
     if (e->testFlag(EventManager::Self))
         return;  // ignore ctcp events generated by user input
@@ -1072,42 +1515,38 @@ void CoreSessionEventProcessor::processCtcpEvent(CtcpEvent *e)
     if (e->type() != EventManager::CtcpEvent || e->ctcpType() != CtcpEvent::Query)
         return;
 
-    handle(e->ctcpCmd(), Q_ARG(CtcpEvent *, e));
+    handle(e->ctcpCmd(), Q_ARG(CtcpEvent*, e));
 }
 
-
-void CoreSessionEventProcessor::defaultHandler(const QString &ctcpCmd, CtcpEvent *e)
+void CoreSessionEventProcessor::defaultHandler(const QString& ctcpCmd, CtcpEvent* e)
 {
     // This handler is only there to avoid warnings for unknown CTCPs
     Q_UNUSED(e);
     Q_UNUSED(ctcpCmd);
 }
 
-
-void CoreSessionEventProcessor::handleCtcpAction(CtcpEvent *e)
+void CoreSessionEventProcessor::handleCtcpAction(CtcpEvent* e)
 {
     // This handler is only there to feed CLIENTINFO
     Q_UNUSED(e);
 }
 
-
-void CoreSessionEventProcessor::handleCtcpClientinfo(CtcpEvent *e)
+void CoreSessionEventProcessor::handleCtcpClientinfo(CtcpEvent* e)
 {
     QStringList supportedHandlers;
-    foreach(QString handler, providesHandlers())
-    supportedHandlers << handler.toUpper();
-    qSort(supportedHandlers);
+    for (const QString& handler : providesHandlers())
+        supportedHandlers << handler.toUpper();
+    std::sort(supportedHandlers.begin(), supportedHandlers.end());
     e->setReply(supportedHandlers.join(" "));
 }
 
-
 // http://www.irchelp.org/irchelp/rfc/ctcpspec.html
 // http://en.wikipedia.org/wiki/Direct_Client-to-Client
-void CoreSessionEventProcessor::handleCtcpDcc(CtcpEvent *e)
+void CoreSessionEventProcessor::handleCtcpDcc(CtcpEvente)
 {
     // DCC support is unfinished, experimental and potentially dangerous, so make it opt-in
     if (!Quassel::isOptionSet("enable-experimental-dcc")) {
-        quInfo() << "DCC disabled, start core with --enable-experimental-dcc if you really want to try it out";
+        qInfo() << "DCC disabled, start core with --enable-experimental-dcc if you really want to try it out";
         return;
     }
 
@@ -1125,8 +1564,8 @@ void CoreSessionEventProcessor::handleCtcpDcc(CtcpEvent *e)
             QHostAddress address;
             quint16 port = params[3].toUShort();
             quint64 size = 0;
-            QString numIp = params[2]; // this is either IPv4 as a 32 bit value, or IPv6 (which always contains a colon)
-            if (numIp.contains(':')) { // IPv6
+            QString numIp = params[2];  // this is either IPv4 as a 32 bit value, or IPv6 (which always contains a colon)
+            if (numIp.contains(':')) {  // IPv6
                 if (!address.setAddress(numIp)) {
                     qWarning() << "Invalid IPv6:" << numIp;
                     return;
@@ -1136,46 +1575,64 @@ void CoreSessionEventProcessor::handleCtcpDcc(CtcpEvent *e)
                 address.setAddress(numIp.toUInt());
             }
 
-            if (port == 0) { // Reverse DCC is indicated by a 0 port
-                emit newEvent(new MessageEvent(Message::Error, e->network(), tr("Reverse DCC SEND not supported"), e->prefix(), e->target(), Message::None, e->timestamp()));
+            if (port == 0) {  // Reverse DCC is indicated by a 0 port
+                emit newEvent(new MessageEvent(Message::Error,
+                                               e->network(),
+                                               tr("Reverse DCC SEND not supported"),
+                                               e->prefix(),
+                                               e->target(),
+                                               Message::None,
+                                               e->timestamp()));
                 return;
             }
             if (port < 1024) {
-                qWarning() << "Privileged port requested:" << port; // FIXME ask user if this is ok
+                qWarning() << "Privileged port requested:" << port;  // FIXME ask user if this is ok
             }
 
-
-            if (params.count() > 4) { // filesize is optional
+            if (params.count() > 4) {  // filesize is optional
                 size = params[4].toULong();
             }
 
             // TODO: check if target is the right thing to use for the partner
-            CoreTransfer *transfer = new CoreTransfer(Transfer::Receive, e->target(), filename, address, port, size, this);
+            CoreTransfer* transfer = new CoreTransfer(Transfer::Direction::Receive, e->target(), filename, address, port, size, this);
             coreSession()->signalProxy()->synchronize(transfer);
             coreSession()->transferManager()->addTransfer(transfer);
         }
         else {
-            emit newEvent(new MessageEvent(Message::Error, e->network(), tr("DCC %1 not supported").arg(cmd), e->prefix(), e->target(), Message::None, e->timestamp()));
+            emit newEvent(new MessageEvent(Message::Error,
+                                           e->network(),
+                                           tr("DCC %1 not supported").arg(cmd),
+                                           e->prefix(),
+                                           e->target(),
+                                           Message::None,
+                                           e->timestamp()));
             return;
         }
     }
 }
 
-
-void CoreSessionEventProcessor::handleCtcpPing(CtcpEvent *e)
+void CoreSessionEventProcessor::handleCtcpPing(CtcpEvent* e)
 {
     e->setReply(e->param().isNull() ? "" : e->param());
 }
 
-
-void CoreSessionEventProcessor::handleCtcpTime(CtcpEvent *e)
+void CoreSessionEventProcessor::handleCtcpTime(CtcpEvent* e)
 {
-    e->setReply(QDateTime::currentDateTime().toString());
+    // Use the ISO standard to avoid locale-specific translated names
+    // Include timezone offset data to show which timezone a user's in, otherwise we're providing
+    // NTP-over-IRC with terrible accuracy.
+    e->setReply(formatDateTimeToOffsetISO(QDateTime::currentDateTime()));
 }
 
-
-void CoreSessionEventProcessor::handleCtcpVersion(CtcpEvent *e)
+void CoreSessionEventProcessor::handleCtcpVersion(CtcpEvent* e)
 {
-    e->setReply(QString("Quassel IRC %1 (built on %2) -- http://www.quassel-irc.org")
-        .arg(Quassel::buildInfo().plainVersionString).arg(Quassel::buildInfo().buildDate));
+    // Deliberately do not translate project name
+    // Use the ISO standard to avoid locale-specific translated names
+    // Use UTC time to provide a consistent string regardless of timezone
+    // (Statistics tracking tools usually only group client versions by exact string matching)
+    e->setReply(QString("Quassel IRC %1 (version date %2) -- https://www.quassel-irc.org")
+                    .arg(Quassel::buildInfo().plainVersionString)
+                    .arg(Quassel::buildInfo().commitDate.isEmpty()
+                             ? "unknown"
+                             : tryFormatUnixEpoch(Quassel::buildInfo().commitDate, Qt::DateFormat::ISODate, true)));
 }