/*
 * Minecraft Forge
 * Copyright (c) 2016-2018.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation version 2.1
 * of the License.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

package net.minecraftforge.fml.server;

import java.io.*;
import java.util.Iterator;
import java.util.List;
import java.util.Set;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import net.minecraft.launchwrapper.Launch;
import net.minecraft.network.INetHandler;
import net.minecraft.network.NetHandlerPlayServer;
import net.minecraft.network.NetworkManager;
import net.minecraft.server.MinecraftServer;
import net.minecraft.server.dedicated.DedicatedServer;
import net.minecraft.server.dedicated.PendingCommand;
import net.minecraft.util.IThreadListener;
import net.minecraft.util.text.translation.LanguageMap;
import net.minecraft.world.storage.SaveFormatOld;
import net.minecraftforge.common.util.CompoundDataFixer;
import net.minecraftforge.fml.common.FMLCommonHandler;
import net.minecraftforge.fml.common.FMLLog;
import net.minecraftforge.fml.common.IFMLSidedHandler;
import net.minecraftforge.fml.common.Loader;
import net.minecraftforge.fml.common.ModContainer;
import net.minecraftforge.fml.common.StartupQuery;
import net.minecraftforge.fml.common.eventhandler.EventBus;
import net.minecraftforge.fml.common.network.FMLNetworkEvent;
import net.minecraftforge.fml.relauncher.Side;

import com.google.common.collect.ImmutableList;
import org.apache.commons.io.IOUtils;

/**
 * Handles primary communication from hooked code into the system
 *
 * The FML entry point is {@link #beginServerLoading(MinecraftServer)} called from
 * {@link net.minecraft.server.dedicated.DedicatedServer}
 *
 * Obfuscated code should focus on this class and other members of the "server"
 * (or "client") code
 *
 * The actual mod loading is handled at arms length by {@link Loader}
 *
 * It is expected that a similar class will exist for each target environment:
 * Bukkit and Client side.
 *
 * It should not be directly modified.
 *
 * @author cpw
 *
 */
public class FMLServerHandler implements IFMLSidedHandler
{
    /**
     * The singleton
     */
    private static final FMLServerHandler INSTANCE = new FMLServerHandler();

    /**
     * A reference to the server itself
     */
    private MinecraftServer server;
    private List<String> injectedModContainers;
    private FMLServerHandler()
    {
        injectedModContainers = FMLCommonHandler.instance().beginLoading(this);
    }
    /**
     * Called to start the whole game off from
     * {@link MinecraftServer#startServer}
     *
     * @param minecraftServer server
     */
    @Override
    public void beginServerLoading(MinecraftServer minecraftServer)
    {
        server = minecraftServer;
        Loader.instance().loadMods(injectedModContainers);
        Loader.instance().preinitializeMods();
    }

    /**
     * Called a bit later on during server initialization to finish loading mods
     */
    @Override
    public void finishServerLoading()
    {
        Loader.instance().initializeMods();
    }

    @Override
    public void haltGame(String message, Throwable exception)
    {
        throw new RuntimeException(message, exception);
    }

    @Override
    public File getSavesDirectory()
    {
        return ((SaveFormatOld) server.getActiveAnvilConverter()).savesDirectory;
    }

    /**
     * Get the server instance
     */
    @Override
    public MinecraftServer getServer()
    {
        return server;
    }

    /**
     * @return the instance
     */
    public static FMLServerHandler instance()
    {
        return INSTANCE;
    }

    /* (non-Javadoc)
     * @see net.minecraftforge.fml.common.IFMLSidedHandler#getAdditionalBrandingInformation()
     */
    @Override
    public List<String> getAdditionalBrandingInformation()
    {
        return ImmutableList.<String>of();
    }

    /* (non-Javadoc)
     * @see net.minecraftforge.fml.common.IFMLSidedHandler#getSide()
     */
    @Override
    public Side getSide()
    {
        return Side.SERVER;
    }

    @Override
    public void showGuiScreen(Object clientGuiElement)
    {

    }

    @Override
    public void queryUser(StartupQuery query) throws InterruptedException
    {
        if (query.getResult() == null)
        {
            FMLLog.log.warn(query.getText());
            query.finish();
        }
        else
        {
            String text = query.getText() +
                    "\n\nRun the command /fml confirm or or /fml cancel to proceed." +
                    "\nAlternatively start the server with -Dfml.queryResult=confirm or -Dfml.queryResult=cancel to preselect the answer.";
            FMLLog.log.warn(text);

            if (!query.isSynchronous()) return; // no-op until mc does commands in another thread (if ever)

            boolean done = false;

            while (!done && server.isServerRunning())
            {
                if (Thread.interrupted()) throw new InterruptedException();

                DedicatedServer dedServer = (DedicatedServer) server;

                // rudimentary command processing, check for fml confirm/cancel and stop commands
                synchronized (dedServer.pendingCommandList)
                {
                    for (Iterator<PendingCommand> it = dedServer.pendingCommandList.iterator(); it.hasNext(); )
                    {
                        String cmd = it.next().command.trim().toLowerCase();

                        if (cmd.equals("/fml confirm"))
                        {
                            FMLLog.log.info("confirmed");
                            query.setResult(true);
                            done = true;
                            it.remove();
                        }
                        else if (cmd.equals("/fml cancel"))
                        {
                            FMLLog.log.info("cancelled");
                            query.setResult(false);
                            done = true;
                            it.remove();
                        }
                        else if (cmd.equals("/stop"))
                        {
                            StartupQuery.abort();
                        }
                    }
                }

                Thread.sleep(10L);
            }

            query.finish();
        }
    }

    @Override
    public boolean isDisplayCloseRequested()
    {
        return false;
    }

    @Override
    public boolean shouldServerShouldBeKilledQuietly()
    {
        return false;
    }

    @Override
    public void addModAsResource(ModContainer container)
    {
        String langFile = "assets/" + container.getModId().toLowerCase() + "/lang/en_us.lang";
        String langFile2 = "assets/" + container.getModId().toLowerCase() + "/lang/en_US.lang";
        File source = container.getSource();
        InputStream stream = null;
        ZipFile zip = null;
        try
        {
            if (source.isDirectory() && (Boolean) Launch.blackboard.get("fml.deobfuscatedEnvironment"))
            {
                File f = new File(source.toURI().resolve(langFile).getPath());
                if (!f.exists())
                    f = new File(source.toURI().resolve(langFile2).getPath());
                if (!f.exists())
                    throw new FileNotFoundException(source.toURI().resolve(langFile).getPath());
                stream = new FileInputStream(f);
            }
            else if (source.exists()) //Fake sources.. Yay coremods -.-
            {
                zip = new ZipFile(source);
                ZipEntry entry = zip.getEntry(langFile);
                if (entry == null) entry = zip.getEntry(langFile2);
                if (entry == null) throw new FileNotFoundException(langFile);
                stream = zip.getInputStream(entry);
            }
            if (stream != null)
                LanguageMap.inject(stream);
        }
        catch (FileNotFoundException e)
        {
            FMLLog.log.warn("Missing English translation for {}: {}", container.getModId(), e.getMessage());
        }
        catch (IOException e)
        {
            // hush
        }
        catch(Exception e)
        {
            FMLLog.log.error(e);
        }
        finally
        {
            IOUtils.closeQuietly(stream);
            IOUtils.closeQuietly(zip);
        }
    }

    @Override
    public String getCurrentLanguage()
    {
        return "en_US";
    }

    @Override
    public void serverStopped()
    {
        // NOOP
    }
    @Override
    public NetworkManager getClientToServerNetworkManager()
    {
        throw new RuntimeException("Missing");
    }
    @Override
    public INetHandler getClientPlayHandler()
    {
        return null;
    }

    @Override
    public void fireNetRegistrationEvent(EventBus bus, NetworkManager manager, Set<String> channelSet, String channel, Side side)
    {
        bus.post(new FMLNetworkEvent.CustomPacketRegistrationEvent<NetHandlerPlayServer>(manager, channelSet, channel, side, NetHandlerPlayServer.class));
    }

    @Override
    public boolean shouldAllowPlayerLogins()
    {
        return DedicatedServer.allowPlayerLogins;
    }

    @Override
    public void allowLogins() {
        DedicatedServer.allowPlayerLogins = true;
    }

    @Override
    public IThreadListener getWorldThread(INetHandler net)
    {
        // Always the server on the dedicated server, eventually add Per-World if Mojang adds world stuff.
        return getServer();
    }

    @Override
    public void processWindowMessages()
    {
        // NOOP
    }

    @Override
    public String stripSpecialChars(String message)
    {
        return message;
    }

    @Override
    public void reloadRenderers() {
        // NOOP
    }

    @Override
    public void fireSidedRegistryEvents()
    {
        // NOOP
    }
    @Override
    public CompoundDataFixer getDataFixer()
    {
        return (CompoundDataFixer)this.server.getDataFixer();
    }

    @Override
    public boolean isDisplayVSyncForced()
    {
        return false;
    }
}