Add client disconnection logic to TransitionService

Problem: disconnecting requires access to CharacterSaver,
which is not available in Client.
Having it in a service like this solves that problem.

Next step is to migrate all calls to Client#disconnect and Client#forceDisconnect
to their TransitionService counterparts.

src/main/java/client/Client.java

@@ -305,6 +305,10 @@ public class Client extends ChannelInboundHandlerAdapter {
         return loggedIn;
     }
 
+    public boolean isInTransition() {
+        return serverTransition;
+    }
+
     public boolean hasBannedIP() {
         boolean ret = false;
         try (Connection con = DatabaseConnection.getConnection();
@@ -833,7 +837,7 @@ public class Client extends ChannelInboundHandlerAdapter {
         }
     }
 
-    private synchronized boolean tryDisconnect() {
+    public synchronized boolean tryDisconnect() {
         if (disconnecting) {
             return false;
         }
@@ -924,7 +928,7 @@ public class Client extends ChannelInboundHandlerAdapter {
         }
     }
 
-    private void clear() {
+    public void clear() {
         // player hard reference removal thanks to Steve (kaito1410)
         if (this.player != null) {
             this.player.empty(true); // clears schedules and stuff

src/main/java/client/autoban/AutobanManager.java

@@ -7,6 +7,7 @@ package client.autoban;
 
 import client.Character;
 import config.YamlConfig;
+import net.netty.GameViolationException;
 import net.server.Server;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -118,11 +119,10 @@ public class AutobanManager {
         if (this.timestamp[type] == time) {
             this.timestampcounter[type]++;
             if (this.timestampcounter[type] >= times) {
-                if (YamlConfig.config.server.USE_AUTOBAN) {
-                    chr.getClient().disconnect(false, false);
-                }
-
                 log.info("Autoban - Chr {} was caught spamming TYPE {} and has been disconnected", chr, type);
+                if (YamlConfig.config.server.USE_AUTOBAN) {
+                    throw new GameViolationException("Auto ban");
+                }
             }
         } else {
             this.timestamp[type] = time;

src/main/java/client/command/CommandContext.java

@@ -3,15 +3,15 @@ package client.command;
 import database.character.CharacterSaver;
 import database.drop.DropProvider;
 import server.shop.ShopFactory;
-import service.ChannelService;
+import service.TransitionService;
 
 /**
  * @author Ponk
  */
 public record CommandContext(CommandsExecutor commandsExecutor, DropProvider dropProvider, ShopFactory shopFactory,
-                             CharacterSaver characterSaver, ChannelService channelService) {
+                             CharacterSaver characterSaver, TransitionService transitionService) {
 
     public CommandContext with(CommandsExecutor ce) {
-        return new CommandContext(ce, this.dropProvider, this.shopFactory, this.characterSaver, this.channelService);
+        return new CommandContext(ce, this.dropProvider, this.shopFactory, this.characterSaver, this.transitionService);
     }
 }

src/main/java/client/command/commands/gm2/SummonCommand.java

@@ -63,7 +63,7 @@ public class SummonCommand extends Command {
 
             if (player.getClient().getChannel() != victim.getClient().getChannel()) {//And then change channel if needed.
                 victim.dropMessage("Changing channel, please wait a moment.");
-                ctx.channelService().changeChannel(victim.getClient(), player.getClient().getChannel());
+                ctx.transitionService().changeChannel(victim.getClient(), player.getClient().getChannel());
             }
 
             try {

src/main/java/net/ChannelDependencies.java

@@ -7,8 +7,8 @@ import database.character.CharacterLoader;
 import database.character.CharacterSaver;
 import database.drop.DropProvider;
 import server.shop.ShopFactory;
-import service.ChannelService;
 import service.NoteService;
+import service.TransitionService;
 
 import java.util.Objects;
 
@@ -18,7 +18,7 @@ import java.util.Objects;
 public record ChannelDependencies(
         CharacterLoader characterLoader, CharacterSaver characterSaver, NoteService noteService,
         FredrickProcessor fredrickProcessor, MakerProcessor makerProcessor, DropProvider dropProvider,
-        CommandsExecutor commandsExecutor, ShopFactory shopFactory, ChannelService channelService
+        CommandsExecutor commandsExecutor, ShopFactory shopFactory, TransitionService transitionService
 ) {
 
     public ChannelDependencies {
@@ -30,6 +30,6 @@ public record ChannelDependencies(
         Objects.requireNonNull(dropProvider);
         Objects.requireNonNull(commandsExecutor);
         Objects.requireNonNull(shopFactory);
-        Objects.requireNonNull(channelService);
+        Objects.requireNonNull(transitionService);
     }
 }

src/main/java/net/PacketProcessor.java

@@ -140,7 +140,7 @@ public final class PacketProcessor {
         registerHandler(RecvOpcode.NAME_TRANSFER, new TransferNameHandler());
         registerHandler(RecvOpcode.CHECK_CHAR_NAME, new TransferNameResultHandler());
         registerHandler(RecvOpcode.WORLD_TRANSFER, new TransferWorldHandler());
-        registerHandler(RecvOpcode.CHANGE_CHANNEL, new ChangeChannelHandler(channelDeps.channelService()));
+        registerHandler(RecvOpcode.CHANGE_CHANNEL, new ChangeChannelHandler(channelDeps.transitionService()));
         registerHandler(RecvOpcode.STRANGE_DATA, LoginRequiringNoOpHandler.getInstance());
         registerHandler(RecvOpcode.GENERAL_CHAT, new GeneralChatHandler(channelDeps.commandsExecutor()));
         registerHandler(RecvOpcode.WHISPER, new WhisperHandler());

src/main/java/net/server/Server.java

@@ -76,8 +76,8 @@ import server.expeditions.ExpeditionBossLog;
 import server.life.PlayerNPCFactory;
 import server.quest.Quest;
 import server.shop.ShopFactory;
-import service.ChannelService;
 import service.NoteService;
+import service.TransitionService;
 import tools.DatabaseConnection;
 import tools.Pair;
 
@@ -982,17 +982,17 @@ public class Server {
         MonsterCardDao monsterCardDao = new MonsterCardDao(connection);
         CharacterLoader characterLoader = new CharacterLoader(monsterCardDao);
         CharacterSaver characterSaver = new CharacterSaver(monsterCardDao);
-        ChannelService channelService = new ChannelService(characterSaver);
+        TransitionService transitionService = new TransitionService(characterSaver);
         NoteService noteService = new NoteService(new NoteDao(connection));
         MakerProcessor makerProcessor = new MakerProcessor(new MakerInfoProvider(new MakerDao(connection)));
         FredrickProcessor fredrickProcessor = new FredrickProcessor(noteService);
         DropProvider dropProvider = new DropProvider(new DropDao(connection));
         ShopFactory shopFactory = new ShopFactory(new ShopDao(connection));
         CommandContext commandContext = new CommandContext(null, dropProvider, shopFactory,
-                characterSaver, channelService);
+                characterSaver, transitionService);
         CommandsExecutor commandsExecutor = new CommandsExecutor(commandContext);
         ChannelDependencies channelDependencies = new ChannelDependencies(characterLoader, characterSaver, noteService,
-                fredrickProcessor, makerProcessor, dropProvider, commandsExecutor, shopFactory, channelService);
+                fredrickProcessor, makerProcessor, dropProvider, commandsExecutor, shopFactory, transitionService);
 
         PacketProcessor.registerGameHandlerDependencies(channelDependencies);
 

src/main/java/net/server/channel/handlers/ChangeChannelHandler.java

@@ -27,16 +27,16 @@ import net.AbstractPacketHandler;
 import net.netty.GameViolationException;
 import net.packet.InPacket;
 import net.server.Server;
-import service.ChannelService;
+import service.TransitionService;
 
 /**
  * @author Matze
  */
 public final class ChangeChannelHandler extends AbstractPacketHandler {
-    private final ChannelService channelService;
+    private final TransitionService transitionService;
 
-    public ChangeChannelHandler(ChannelService channelService) {
-        this.channelService = channelService;
+    public ChangeChannelHandler(TransitionService transitionService) {
+        this.transitionService = transitionService;
     }
 
     @Override
@@ -51,6 +51,6 @@ public final class ChangeChannelHandler extends AbstractPacketHandler {
             return;
         }
 
-        channelService.changeChannel(c, channel);
+        transitionService.changeChannel(c, channel);
     }
 }

src/main/java/service/ChannelService.java

@@ -1,79 +0,0 @@
-package service;
-
-import client.Client;
-import client.inventory.InventoryType;
-import database.character.CharacterSaver;
-import net.server.Server;
-import server.maps.FieldLimit;
-import server.maps.MiniDungeonInfo;
-import tools.PacketCreator;
-
-import java.io.IOException;
-import java.net.InetAddress;
-
-public class ChannelService {
-    private final Server server = Server.getInstance();
-    private final CharacterSaver chrSaver;
-
-    public ChannelService(CharacterSaver characterSaver) {
-        this.chrSaver = characterSaver;
-    }
-
-    public void changeChannel(Client c, int channel) {
-        var chr = c.getPlayer();
-        if (chr.isBanned()) {
-            c.disconnect(false, false);
-            return;
-        }
-
-        if (!chr.isAlive() || FieldLimit.CANNOTMIGRATE.check(chr.getMap().getFieldLimit())) {
-            c.sendPacket(PacketCreator.enableActions());
-            return;
-        }
-
-        if (MiniDungeonInfo.isDungeonMap(chr.getMapId())) {
-            c.sendPacket(PacketCreator.serverNotice(5, "Changing channels or entering Cash Shop or MTS are disabled when inside a Mini-Dungeon."));
-            c.sendPacket(PacketCreator.enableActions());
-            return;
-        }
-
-        String[] socket = Server.getInstance().getInetSocket(c, c.getWorld(), channel);
-        if (socket == null) {
-            c.sendPacket(PacketCreator.serverNotice(1, "Channel " + channel + " is currently disabled. Try another channel."));
-            c.sendPacket(PacketCreator.enableActions());
-            return;
-        }
-
-        chr.closePlayerInteractions();
-        chr.closePartySearchInteractions();
-
-        chr.unregisterChairBuff();
-        server.getPlayerBuffStorage().addBuffsToStorage(chr.getId(), chr.getAllBuffs());
-        server.getPlayerBuffStorage().addDiseasesToStorage(chr.getId(), chr.getAllDiseases());
-        chr.setDisconnectedFromChannelWorld();
-        chr.notifyMapTransferToPartner(-1);
-        chr.removeIncomingInvites();
-        chr.cancelAllBuffs(true);
-        chr.cancelAllDebuffs();
-        chr.cancelBuffExpireTask();
-        chr.cancelDiseaseExpireTask();
-        chr.cancelSkillCooldownTask();
-        chr.cancelQuestExpirationTask();
-        //Cancelling magicdoor? Nope
-        //Cancelling mounts? Noty
-
-        chr.getInventory(InventoryType.EQUIPPED).checked(false); //test
-        chr.getMap().removePlayer(chr);
-        chr.clearBanishPlayerData();
-        c.getChannelServer().removePlayer(chr);
-
-        chrSaver.save(chr);
-
-        chr.setSessionTransitionState();
-        try {
-            c.sendPacket(PacketCreator.getChannelChange(InetAddress.getByName(socket[0]), Integer.parseInt(socket[1])));
-        } catch (IOException e) {
-            e.printStackTrace();
-        }
-    }
-}

src/main/java/service/TransitionService.java

@@ -0,0 +1,245 @@
+package service;
+
+import client.BuddyList;
+import client.Client;
+import client.inventory.InventoryType;
+import config.YamlConfig;
+import constants.id.MapId;
+import database.character.CharacterSaver;
+import net.server.Server;
+import net.server.guild.Guild;
+import net.server.guild.GuildCharacter;
+import net.server.guild.GuildPackets;
+import net.server.world.*;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import scripting.event.EventInstanceManager;
+import server.ThreadManager;
+import server.maps.FieldLimit;
+import server.maps.MapleMap;
+import server.maps.MiniDungeonInfo;
+import tools.PacketCreator;
+
+import java.io.IOException;
+import java.net.InetAddress;
+
+public class TransitionService {
+    private static final Logger log = LoggerFactory.getLogger(TransitionService.class);
+    private final Server server = Server.getInstance();
+    private final CharacterSaver chrSaver;
+
+    public TransitionService(CharacterSaver characterSaver) {
+        this.chrSaver = characterSaver;
+    }
+
+    public void changeChannel(Client c, int channel) {
+        var chr = c.getPlayer();
+        if (chr.isBanned()) {
+            disconnect(c, false, false);
+            return;
+        }
+
+        if (!chr.isAlive() || FieldLimit.CANNOTMIGRATE.check(chr.getMap().getFieldLimit())) {
+            c.sendPacket(PacketCreator.enableActions());
+            return;
+        }
+
+        if (MiniDungeonInfo.isDungeonMap(chr.getMapId())) {
+            c.sendPacket(PacketCreator.serverNotice(5, "Changing channels or entering Cash Shop or MTS are disabled when inside a Mini-Dungeon."));
+            c.sendPacket(PacketCreator.enableActions());
+            return;
+        }
+
+        String[] socket = Server.getInstance().getInetSocket(c, c.getWorld(), channel);
+        if (socket == null) {
+            c.sendPacket(PacketCreator.serverNotice(1, "Channel " + channel + " is currently disabled. Try another channel."));
+            c.sendPacket(PacketCreator.enableActions());
+            return;
+        }
+
+        chr.closePlayerInteractions();
+        chr.closePartySearchInteractions();
+
+        chr.unregisterChairBuff();
+        server.getPlayerBuffStorage().addBuffsToStorage(chr.getId(), chr.getAllBuffs());
+        server.getPlayerBuffStorage().addDiseasesToStorage(chr.getId(), chr.getAllDiseases());
+        chr.setDisconnectedFromChannelWorld();
+        chr.notifyMapTransferToPartner(-1);
+        chr.removeIncomingInvites();
+        chr.cancelAllBuffs(true);
+        chr.cancelAllDebuffs();
+        chr.cancelBuffExpireTask();
+        chr.cancelDiseaseExpireTask();
+        chr.cancelSkillCooldownTask();
+        chr.cancelQuestExpirationTask();
+        //Cancelling magicdoor? Nope
+        //Cancelling mounts? Noty
+
+        chr.getInventory(InventoryType.EQUIPPED).checked(false); //test
+        chr.getMap().removePlayer(chr);
+        chr.clearBanishPlayerData();
+        c.getChannelServer().removePlayer(chr);
+
+        chrSaver.save(chr);
+
+        chr.setSessionTransitionState();
+        try {
+            c.sendPacket(PacketCreator.getChannelChange(InetAddress.getByName(socket[0]), Integer.parseInt(socket[1])));
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    // TODO: take code from Client#disconnect & forceDisconnect. Move it here.
+    // It's not gonna be easy to move all instances of c.disconnect, but it has to be done.
+    public void disconnect(final Client c, final boolean shutdown, final boolean cashShop) {
+        if (c.tryDisconnect()) {
+            ThreadManager.getInstance().newTask(() -> disconnectInternal(c, shutdown, cashShop));
+        }
+    }
+
+    public void forceDisconnect(Client c) {
+        if (c.tryDisconnect()) {
+            disconnectInternal(c, true, false);
+        }
+    }
+
+    private void disconnectInternal(Client c, boolean shutdown, boolean cashShop) {
+        var chr = c.getPlayer();
+        if (chr != null && chr.isLoggedin() && chr.getClient() != null) {
+            final int messengerid = chr.getMessenger() == null ? 0 : chr.getMessenger().getId();
+            final BuddyList bl = chr.getBuddylist();
+            final MessengerCharacter messengerChr = new MessengerCharacter(chr, 0);
+            final GuildCharacter guildChr = chr.getMGC();
+            final Guild guild = chr.getGuild();
+
+            chr.cancelMagicDoor();
+
+            final World wserv = c.getWorldServer();   // obviously wserv is NOT null if this chr was online on it
+            try {
+                removePlayer(c, wserv, c.isInTransition());
+
+                final int channel = c.getChannel();
+                if (!(channel == -1 || shutdown)) {
+                    if (!cashShop) {
+                        if (!c.isInTransition()) { // meaning not changing channels
+                            if (messengerid > 0) {
+                                wserv.leaveMessenger(messengerid, messengerChr);
+                            }
+
+                            chr.forfeitExpirableQuests();    //This is for those quests that you have to stay logged in for a certain amount of time
+
+                            if (guild != null) {
+                                final Server server = Server.getInstance();
+                                server.setGuildMemberOnline(chr, false, chr.getClient().getChannel());
+                                chr.sendPacket(GuildPackets.showGuildInfo(chr));
+                            }
+                            if (bl != null) {
+                                wserv.loggedOff(chr.getName(), chr.getId(), channel, chr.getBuddylist().getBuddyIds());
+                            }
+                        }
+                    } else {
+                        if (!c.isInTransition()) { // if dc inside of cash shop.
+                            if (bl != null) {
+                                wserv.loggedOff(chr.getName(), chr.getId(), channel, chr.getBuddylist().getBuddyIds());
+                            }
+                        }
+                    }
+                }
+            } catch (final Exception e) {
+                log.error("Account stuck", e);
+            } finally {
+                if (!c.isInTransition()) {
+                    if (guildChr != null) {
+                        guildChr.setCharacter(null);
+                    }
+                    wserv.removePlayer(chr);
+                    //getChannelServer().removePlayer(player); already being done
+
+                    chr.cancelAllDebuffs();
+                    chrSaver.save(chr);
+
+                    chr.logOff();
+                    if (YamlConfig.config.server.INSTANT_NAME_CHANGE) {
+                        chr.doPendingNameChange();
+                    }
+                    c.clear();
+                } else {
+                    c.getChannelServer().removePlayer(chr);
+
+                    chr.cancelAllDebuffs();
+                    chrSaver.save(chr);
+                }
+            }
+        }
+    }
+
+    private void removePlayer(Client c, World world, boolean serverTransition) {
+        var chr = c.getPlayer();
+        try {
+            chr.setDisconnectedFromChannelWorld();
+            chr.notifyMapTransferToPartner(-1);
+            chr.removeIncomingInvites();
+            chr.cancelAllBuffs(true);
+
+            chr.closePlayerInteractions();
+            chr.closePartySearchInteractions();
+
+            if (!serverTransition) {    // thanks MedicOP for detecting an issue with party leader change on changing channels
+                removePartyPlayer(c, world);
+
+                EventInstanceManager eim = chr.getEventInstance();
+                if (eim != null) {
+                    eim.playerDisconnected(chr);
+                }
+
+                if (chr.getMonsterCarnival() != null) {
+                    chr.getMonsterCarnival().playerDisconnected(chr.getId());
+                }
+
+                if (chr.getAriantColiseum() != null) {
+                    chr.getAriantColiseum().playerDisconnected(chr);
+                }
+            }
+
+            if (chr.getMap() != null) {
+                int mapId = chr.getMapId();
+                chr.getMap().removePlayer(chr);
+                if (MapId.isDojo(mapId)) {
+                    c.getChannelServer().freeDojoSectionIfEmpty(mapId);
+                }
+
+                if (chr.getMap().getHPDec() > 0) {
+                    world.removePlayerHpDecrease(chr);
+                }
+            }
+
+        } catch (final Throwable t) {
+            log.error("Account stuck", t);
+        }
+    }
+
+    private void removePartyPlayer(Client c, World world) {
+        var chr = c.getPlayer();
+        MapleMap map = chr.getMap();
+        final Party party = chr.getParty();
+        final int idz = chr.getId();
+
+        if (party != null) {
+            final PartyCharacter chrp = new PartyCharacter(chr);
+            chrp.setOnline(false);
+            world.updateParty(party.getId(), PartyOperation.LOG_ONOFF, chrp);
+            if (party.getLeader().getId() == idz && map != null) {
+                PartyCharacter lchr = null;
+                for (PartyCharacter pchr : party.getMembers()) {
+                    if (pchr != null && pchr.getId() != idz && (lchr == null || lchr.getLevel() <= pchr.getLevel()) && map.getCharacterById(pchr.getId()) != null) {
+                        lchr = pchr;
+                    }
+                }
+                if (lchr != null) {
+                    world.updateParty(party.getId(), PartyOperation.CHANGE_LEADER, lchr);
+                }
+            }
+        }
+    }
+}