de.minigames.mclib.nms.v18.NetworkManager1_8.java Source code

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Here is the source code for de.minigames.mclib.nms.v18.NetworkManager1_8.java

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/*
Copyright 2016 by minigameslib.de
All rights reserved.
If you do not own a hand-signed commercial license from minigames.de
you are not allowed to use this software in any way except using
GPL (see below).
    
------
    
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
    
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
    
You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
    
*/

package de.minigames.mclib.nms.v18;

import java.lang.reflect.Field;
import java.util.List;
import java.util.function.BiConsumer;

import org.bukkit.craftbukkit.v1_8_R1.entity.CraftPlayer;
import org.bukkit.entity.Player;

import de.minigameslib.mclib.api.items.ResourceServiceInterface.ResourcePackStatus;
import io.netty.channel.Channel;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelPipeline;
import io.netty.handler.codec.MessageToMessageDecoder;
import net.minecraft.server.v1_8_R1.EnumResourcePackStatus;
import net.minecraft.server.v1_8_R1.NetworkManager;
import net.minecraft.server.v1_8_R1.Packet;
import net.minecraft.server.v1_8_R1.PacketPlayInResourcePackStatus;

/**
 * A special network manager for 1.8
 * 
 * @author mepeisen
 *
 */
public class NetworkManager1_8 {

    /**
     * reflection nms field
     */
    private static Field channelField;

    /**
     * reflection nms field
     */
    static Field enumField;

    static {
        try {
            channelField = NetworkManager.class.getDeclaredField("i"); //$NON-NLS-1$
            channelField.setAccessible(true);
            enumField = PacketPlayInResourcePackStatus.class.getDeclaredField("b"); //$NON-NLS-1$
            enumField.setAccessible(true);
        } catch (NoSuchFieldException ex) {
            // TODO logging
        }
    }

    /**
     * Hook into network traffic and listen for resource pack status changes. Spigot 1.8 does not have the proper event to listen for this packet.
     * 
     * @param player
     * @param consumer
     */
    public static void hookResourcePackStatus(Player player, BiConsumer<Player, ResourcePackStatus> consumer) {
        final NetworkManager manager = ((CraftPlayer) player).getHandle().playerConnection.networkManager;
        Channel channel = null;
        try {
            channel = (Channel) channelField.get(manager);
        } catch (IllegalArgumentException | IllegalAccessException e) {
            // TODO logging
            return;
        }

        final ChannelPipeline pipe = channel.pipeline();

        final ChannelHandler handler = new MessageToMessageDecoder<Packet>() {
            @Override
            protected void decode(ChannelHandlerContext chc, Packet packet, List<Object> out) throws Exception {
                if (packet instanceof PacketPlayInResourcePackStatus) {
                    try {
                        final EnumResourcePackStatus status = (EnumResourcePackStatus) enumField.get(packet);
                        switch (status) {
                        case ACCEPTED:
                            consumer.accept(player, ResourcePackStatus.ACCEPTED);
                            break;
                        case DECLINED:
                            consumer.accept(player, ResourcePackStatus.DECLINED);
                            break;
                        case FAILED_DOWNLOAD:
                            consumer.accept(player, ResourcePackStatus.FAILED_DOWNLOAD);
                            break;
                        case SUCCESSFULLY_LOADED:
                            consumer.accept(player, ResourcePackStatus.SUCCESSFULLY_LOADED);
                            break;
                        default:
                            break;
                        }
                    } catch (IllegalArgumentException | IllegalAccessException e) {
                        // TODO logging
                    }
                }
                out.add(packet);
            }
        };

        pipe.addAfter("decoder", //$NON-NLS-1$
                "mclib", //$NON-NLS-1$
                handler);
    }

}