/*
 * Copyright (c) 2019-2020 GeyserMC. http://geysermc.org
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @author GeyserMC
 * @link https://github.com/GeyserMC/Geyser
 */

package org.geysermc.connector.network.translators.java;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import org.geysermc.connector.GeyserConnector;
import org.geysermc.connector.network.addon.AddonListener;
import org.geysermc.connector.network.addon.AddonListenerRegistry;
import org.geysermc.connector.network.session.GeyserSession;
import org.geysermc.connector.network.translators.PacketTranslator;
import org.geysermc.connector.network.translators.Translator;

import com.github.steveice10.mc.protocol.packet.ingame.client.ClientPluginMessagePacket;
import com.github.steveice10.mc.protocol.packet.ingame.server.ServerPluginMessagePacket;
import org.geysermc.connector.utils.NetworkUtils;

import java.nio.charset.StandardCharsets;
import java.util.Map;

@Translator(packet = ServerPluginMessagePacket.class)
public class JavaPluginMessageTranslator extends PacketTranslator<ServerPluginMessagePacket> {

    private static byte[] brandData;

    static {
        byte[] data = GeyserConnector.NAME.getBytes(StandardCharsets.UTF_8);
        byte[] varInt = writeVarInt(data.length);
        brandData = new byte[varInt.length + data.length];
        System.arraycopy(varInt, 0, brandData, 0, varInt.length);
        System.arraycopy(data, 0, brandData, varInt.length, data.length);
    }


    @Override
    public void translate(ServerPluginMessagePacket packet, GeyserSession session) {
        if (packet.getChannel().equals("minecraft:brand")) {
            session.sendDownstreamPacket(
                    new ClientPluginMessagePacket(packet.getChannel(), brandData)
            );
        }
        if (packet.getChannel().equals("minecraft:register")) {
            session.sendDownstreamPacket(new ClientPluginMessagePacket(packet.getChannel(), AddonListener.PLUGIN_MESSAGE_CHANNEL.getBytes(StandardCharsets.UTF_8)));
        }

        if (!packet.getChannel().equals(AddonListener.PLUGIN_MESSAGE_CHANNEL)) {
            return;
        }

        for (Map.Entry<String, AddonListener<?>> entry : AddonListenerRegistry.getListeners().entrySet()) {
            ByteBuf buffer = Unpooled.wrappedBuffer(packet.getData());
            String subChannel = NetworkUtils.readString(buffer);
            if (!subChannel.equals(entry.getKey())) {
                continue;
            }

            entry.getValue().onMessageReceive(session, buffer);
        }
    }

    private static byte[] writeVarInt(int value) {
        byte[] data = new byte[getVarIntLength(value)];
        int index = 0;
        do {
            byte temp = (byte)(value & 0b01111111);
            value >>>= 7;
            if (value != 0) {
                temp |= 0b10000000;
            }
            data[index] = temp;
            index++;
        } while (value != 0);
        return data;
    }

    private static int getVarIntLength(int number) {
        if ((number & 0xFFFFFF80) == 0) {
            return 1;
        } else if ((number & 0xFFFFC000) == 0) {
            return 2;
        } else if ((number & 0xFFE00000) == 0) {
            return 3;
        } else if ((number & 0xF0000000) == 0) {
            return 4;
        }
        return 5;
    }
}