001/*
002 * Forge Mod Loader
003 * Copyright (c) 2012-2013 cpw.
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the GNU Lesser Public License v2.1
006 * which accompanies this distribution, and is available at
007 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
008 * 
009 * Contributors:
010 *     cpw - implementation
011 */
012
013package cpw.mods.fml.common.network;
014
015import static cpw.mods.fml.common.network.FMLPacket.Type.MOD_LIST_REQUEST;
016import static cpw.mods.fml.common.network.FMLPacket.Type.MOD_LIST_RESPONSE;
017
018import java.util.List;
019import java.util.Map;
020import java.util.Map.Entry;
021import java.util.Set;
022
023import net.minecraft.network.INetworkManager;
024import net.minecraft.network.packet.NetHandler;
025
026import com.google.common.collect.Lists;
027import com.google.common.collect.Maps;
028import com.google.common.io.ByteArrayDataInput;
029import com.google.common.io.ByteArrayDataOutput;
030import com.google.common.io.ByteStreams;
031
032import cpw.mods.fml.common.FMLCommonHandler;
033import cpw.mods.fml.common.FMLLog;
034import cpw.mods.fml.common.Loader;
035import cpw.mods.fml.common.ModContainer;
036
037public class ModListRequestPacket extends FMLPacket
038{
039    private List<String> sentModList;
040    private byte compatibilityLevel;
041
042    public ModListRequestPacket()
043    {
044        super(MOD_LIST_REQUEST);
045    }
046
047    @Override
048    public byte[] generatePacket(Object... data)
049    {
050        ByteArrayDataOutput dat = ByteStreams.newDataOutput();
051        Set<ModContainer> activeMods = FMLNetworkHandler.instance().getNetworkModList();
052        dat.writeInt(activeMods.size());
053        for (ModContainer mc : activeMods)
054        {
055            dat.writeUTF(mc.getModId());
056        }
057        dat.writeByte(FMLNetworkHandler.getCompatibilityLevel());
058        return dat.toByteArray();
059    }
060
061    @Override
062    public FMLPacket consumePacket(byte[] data)
063    {
064        sentModList = Lists.newArrayList();
065        ByteArrayDataInput in = ByteStreams.newDataInput(data);
066        int listSize = in.readInt();
067        for (int i = 0; i < listSize; i++)
068        {
069            sentModList.add(in.readUTF());
070        }
071        try
072        {
073            compatibilityLevel = in.readByte();
074        }
075        catch (IllegalStateException e)
076        {
077            FMLLog.fine("No compatibility byte found - the server is too old");
078        }
079        return this;
080    }
081
082    /**
083     *
084     * This packet is executed on the client to evaluate the server's mod list against
085     * the client
086     *
087     * @see cpw.mods.fml.common.network.FMLPacket#execute(INetworkManager, FMLNetworkHandler, NetHandler, String)
088     */
089    @Override
090    public void execute(INetworkManager mgr, FMLNetworkHandler handler, NetHandler netHandler, String userName)
091    {
092        List<String> missingMods = Lists.newArrayList();
093        Map<String,String> modVersions = Maps.newHashMap();
094        Map<String, ModContainer> indexedModList = Maps.newHashMap(Loader.instance().getIndexedModList());
095
096        for (String m : sentModList)
097        {
098            ModContainer mc = indexedModList.get(m);
099            if (mc == null)
100            {
101                missingMods.add(m);
102                continue;
103            }
104            indexedModList.remove(m);
105            modVersions.put(m, mc.getVersion());
106        }
107
108        if (indexedModList.size()>0)
109        {
110            for (Entry<String, ModContainer> e : indexedModList.entrySet())
111            {
112                if (e.getValue().isNetworkMod())
113                {
114                    NetworkModHandler missingHandler = FMLNetworkHandler.instance().findNetworkModHandler(e.getValue());
115                    if (missingHandler.requiresServerSide())
116                    {
117                        // TODO : what should we do if a mod is marked "serverSideRequired"? Stop the connection?
118                        FMLLog.warning("The mod %s was not found on the server you connected to, but requested that the server side be present", e.getKey());
119                    }
120                }
121            }
122        }
123
124        FMLLog.fine("The server has compatibility level %d", compatibilityLevel);
125        FMLCommonHandler.instance().getSidedDelegate().setClientCompatibilityLevel(compatibilityLevel);
126
127        mgr.addToSendQueue(PacketDispatcher.getPacket("FML", FMLPacket.makePacket(MOD_LIST_RESPONSE, modVersions, missingMods)));
128    }
129}