LiteLoader / LiteLoader · Files

/*
 * This file is part of LiteLoader.
 * Copyright (C) 2012-16 Adam Mummery-Smith
 * All Rights Reserved.
 */
package com.mumfrey.liteloader.core;

import java.util.List;

import com.mumfrey.liteloader.PacketHandler;
import com.mumfrey.liteloader.ServerChatFilter;
import com.mumfrey.liteloader.api.InterfaceProvider;
import com.mumfrey.liteloader.api.Listener;
import com.mumfrey.liteloader.common.transformers.PacketEventInfo;
import com.mumfrey.liteloader.core.event.HandlerList;
import com.mumfrey.liteloader.core.event.HandlerList.ReturnLogicOp;
import com.mumfrey.liteloader.core.runtime.Packets;
import com.mumfrey.liteloader.interfaces.FastIterable;
import com.mumfrey.liteloader.util.log.LiteLoaderLogger;

import net.minecraft.entity.player.EntityPlayerMP;
import net.minecraft.network.INetHandler;
import net.minecraft.network.NetHandlerPlayServer;
import net.minecraft.network.Packet;
import net.minecraft.network.login.server.SPacketLoginSuccess;
import net.minecraft.network.play.client.CPacketChatMessage;
import net.minecraft.network.play.client.CPacketClientSettings;
import net.minecraft.network.play.client.CPacketCustomPayload;
import net.minecraft.network.play.server.SPacketChat;
import net.minecraft.network.play.server.SPacketCustomPayload;
import net.minecraft.network.play.server.SPacketJoinGame;
import net.minecraft.util.IThreadListener;

/**
 * Packet event handling
 *
 * @author Adam Mummery-Smith
 */
public abstract class PacketEvents implements InterfaceProvider
{
    protected static PacketEvents instance;

    class PacketHandlerList extends HandlerList<PacketHandler>
    {
        private static final long serialVersionUID = 1L;
        
        /**
         * ctor
         */
        PacketHandlerList()
        {
            super(PacketHandler.class, ReturnLogicOp.AND_BREAK_ON_FALSE);
        }
    }

    /**
     * Reference to the loader instance
     */
    protected final LiteLoader loader;

    private PacketHandlerList[] packetHandlers = new PacketHandlerList[Packets.count()];

    private FastIterable<ServerChatFilter> serverChatFilters = new HandlerList<ServerChatFilter>(ServerChatFilter.class,
                                                                                                    ReturnLogicOp.AND_BREAK_ON_FALSE);

    private final int loginSuccessPacketId   = Packets.SPacketLoginSuccess.getIndex();
    private final int serverChatPacketId     = Packets.SPacketChat.getIndex();
    private final int clientChatPacketId     = Packets.CPacketChatMessage.getIndex();
    private final int joinGamePacketId       = Packets.SPacketJoinGame.getIndex();
    private final int serverPayloadPacketId  = Packets.SPacketCustomPayload.getIndex();
    private final int clientPayloadPacketId  = Packets.CPacketCustomPayload.getIndex();
    private final int clientSettingsPacketId = Packets.CPacketClientSettings.getIndex();

    /**
     * ctor
     */
    public PacketEvents()
    {
        PacketEvents.instance = this;
        this.loader = LiteLoader.getInstance();
    }

    @Override
    public Class<? extends Listener> getListenerBaseType()
    {
        return Listener.class;
    }

    @Override
    public void registerInterfaces(InterfaceRegistrationDelegate delegate)
    {
        delegate.registerInterface(PacketHandler.class);
        delegate.registerInterface(ServerChatFilter.class);
    }

    @Override
    public void initProvider()
    {
    }

    /**
     * @param serverChatFilter
     */
    public void registerServerChatFilter(ServerChatFilter serverChatFilter)
    {
        this.serverChatFilters.add(serverChatFilter);
    }

    /**
     * Register a new packet handler
     * 
     * @param handler
     */
    public void registerPacketHandler(PacketHandler handler)
    {
        List<Class<? extends Packet<?>>> handledPackets = handler.getHandledPackets();
        if (handledPackets != null)
        {
            for (Class<? extends Packet<?>> packetClass : handledPackets)
            {
                String packetClassName = packetClass.getName();
                int packetId = Packets.indexOf(packetClassName);
                if (packetId == -1 || packetId >= this.packetHandlers.length)
                {
                    LiteLoaderLogger.warning("PacketHandler %s attempted to register a handler for unupported packet class %s",
                            handler.getName(), packetClassName);
                    continue;
                }

                if (this.packetHandlers[packetId] == null)
                {
                    this.packetHandlers[packetId] = new PacketHandlerList();
                }

                this.packetHandlers[packetId].add(handler);
            }
        }
    }

    /**
     * Event callback
     * 
     * @param e
     * @param netHandler
     */
    public static void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler)
    {
        PacketEvents.instance.handlePacket(e, netHandler, e.getPacketId());
    }

    private void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, int packetId)
    {
        Packets packetInfo = Packets.packets[e.getPacketId()];
        IThreadListener threadListener = this.getPacketContextListener(packetInfo.getContext());
        if (threadListener != null && !threadListener.isCallingFromMinecraftThread())
        {
            this.handleAsyncPacketEvent(e, netHandler, packetId);
            return;
        }

        if (this.handlePacketEvent(e, netHandler, packetId) || this.packetHandlers[packetId] == null || e.isCancelled())
        {
            return;
        }

        if (this.packetHandlers[packetId].all().handlePacket(netHandler, e.getSource()))
        {
            return;
        }

        e.cancel();
    }

    /**
     * @param context
     */
    protected abstract IThreadListener getPacketContextListener(Packets.Context context);

    /**
     * @param e
     * @param netHandler
     * @param packetId
     */
    protected void handleAsyncPacketEvent(PacketEventInfo<Packet<?>> e, INetHandler netHandler, int packetId)
    {
        Packet<?> packet = e.getSource();

        if (packetId == this.loginSuccessPacketId)
        {
            this.handlePacket(e, netHandler, (SPacketLoginSuccess)packet);
        }
    }

    /**
     * @param e
     * @param netHandler
     * @param packetId
     * @return true if the packet was handled by a local handler and shouldn't
     *      be forwarded to later handlers
     */
    protected boolean handlePacketEvent(PacketEventInfo<Packet<?>> e, INetHandler netHandler, int packetId)
    {
        Packet<?> packet = e.getSource();
        
        if (packetId == this.serverChatPacketId)
        {
            this.handlePacket(e, netHandler, (SPacketChat)packet);
            return true;
        }

        if (packetId == this.clientChatPacketId)
        {
            this.handlePacket(e, netHandler, (CPacketChatMessage)packet);
            return true;
        }

        if (packetId == this.joinGamePacketId)
        {
            this.handlePacket(e, netHandler, (SPacketJoinGame)packet);
            return true;
        }

        if (packetId == this.serverPayloadPacketId)
        {
            this.handlePacket(e, netHandler, (SPacketCustomPayload)packet);
            return true;
        }

        if (packetId == this.clientPayloadPacketId)
        {
            this.handlePacket(e, netHandler, (CPacketCustomPayload)packet);
            return true;
        }

        if (packetId == this.clientSettingsPacketId)
        {
            this.handlePacket(e, netHandler, (CPacketClientSettings)packet);
            return true;
        }

        return false;
    }

    /**
     * @param e
     * @param netHandler
     * @param packet
     */
    protected abstract void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, SPacketLoginSuccess packet);

    /**
     * S02PacketChat::processPacket()
     * 
     * @param netHandler
     * @param packet
     */
    protected abstract void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, SPacketChat packet);

    /**
     * S02PacketChat::processPacket()
     * 
     * @param netHandler
     * @param packet
     */
    protected void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, CPacketChatMessage packet)
    {
        EntityPlayerMP player = netHandler instanceof NetHandlerPlayServer ? ((NetHandlerPlayServer)netHandler).player : null;

        if (!this.serverChatFilters.all().onChat(player, packet, packet.getMessage()))
        {
            e.cancel();
        }
    }

    /**
     * SPacketJoinGame::processPacket()
     * 
     * @param netHandler
     * @param packet
     */
    protected void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, SPacketJoinGame packet)
    {
        this.loader.onJoinGame(netHandler, packet);
    }

    /**
     * S3FPacketCustomPayload::processPacket()
     * 
     * @param netHandler
     * @param packet
     */
    protected void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, SPacketCustomPayload packet)
    {
        LiteLoader.getClientPluginChannels().onPluginChannelMessage(packet);
    }

    /**
     * C17PacketCustomPayload::processPacket()
     * 
     * @param netHandler
     * @param packet
     */
    protected void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, CPacketCustomPayload packet)
    {
        LiteLoader.getServerPluginChannels().onPluginChannelMessage(netHandler, packet);
    }

    /**
     * C15PacketClientSettings::processPacket()
     * 
     * @param e
     * @param netHandler
     * @param packet
     */
    private void handlePacket(PacketEventInfo<Packet<?>> e, INetHandler netHandler, CPacketClientSettings packet)
    {
        if (netHandler instanceof NetHandlerPlayServer)
        {
            LiteLoaderEventBroker.broker.onPlayerSettingsReceived(((NetHandlerPlayServer)netHandler).player, packet);
        }
    }
}