minecraft-src/net/minecraft/client/multiplayer/ServerList.java

package net.minecraft.client.multiplayer;

import com.google.common.collect.Lists;
import com.mojang.logging.LogUtils;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.List;
import java.util.Objects;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.Util;
import net.minecraft.client.Minecraft;
import net.minecraft.nbt.CompoundTag;
import net.minecraft.nbt.ListTag;
import net.minecraft.nbt.NbtIo;
import net.minecraft.util.thread.ConsecutiveExecutor;
import org.jetbrains.annotations.Nullable;
import org.slf4j.Logger;

@Environment(EnvType.CLIENT)
public class ServerList {
	private static final Logger LOGGER = LogUtils.getLogger();
	private static final ConsecutiveExecutor IO_EXECUTOR = new ConsecutiveExecutor(Util.backgroundExecutor(), "server-list-io");
	private static final int MAX_HIDDEN_SERVERS = 16;
	private final Minecraft minecraft;
	private final List<ServerData> serverList = Lists.<ServerData>newArrayList();
	private final List<ServerData> hiddenServerList = Lists.<ServerData>newArrayList();

	public ServerList(Minecraft minecraft) {
		this.minecraft = minecraft;
	}

	/**
	 * Loads a list of servers from servers.dat, by running ServerData.getServerDataFromNBTCompound on each NBT compound found in the "servers" tag list.
	 */
	public void load() {
		try {
			this.serverList.clear();
			this.hiddenServerList.clear();
			CompoundTag compoundTag = NbtIo.read(this.minecraft.gameDirectory.toPath().resolve("servers.dat"));
			if (compoundTag == null) {
				return;
			}

			compoundTag.getListOrEmpty("servers").compoundStream().forEach(compoundTagx -> {
				ServerData serverData = ServerData.read(compoundTagx);
				if (compoundTagx.getBooleanOr("hidden", false)) {
					this.hiddenServerList.add(serverData);
				} else {
					this.serverList.add(serverData);
				}
			});
		} catch (Exception var2) {
			LOGGER.error("Couldn't load server list", (Throwable)var2);
		}
	}

	/**
	 * Runs getNBTCompound on each ServerData instance, puts everything into a "servers" NBT list and writes it to servers.dat.
	 */
	public void save() {
		try {
			ListTag listTag = new ListTag();

			for (ServerData serverData : this.serverList) {
				CompoundTag compoundTag = serverData.write();
				compoundTag.putBoolean("hidden", false);
				listTag.add(compoundTag);
			}

			for (ServerData serverData : this.hiddenServerList) {
				CompoundTag compoundTag = serverData.write();
				compoundTag.putBoolean("hidden", true);
				listTag.add(compoundTag);
			}

			CompoundTag compoundTag2 = new CompoundTag();
			compoundTag2.put("servers", listTag);
			Path path = this.minecraft.gameDirectory.toPath();
			Path path2 = Files.createTempFile(path, "servers", ".dat");
			NbtIo.write(compoundTag2, path2);
			Path path3 = path.resolve("servers.dat_old");
			Path path4 = path.resolve("servers.dat");
			Util.safeReplaceFile(path4, path2, path3);
		} catch (Exception var7) {
			LOGGER.error("Couldn't save server list", (Throwable)var7);
		}
	}

	/**
	 * Gets the ServerData instance stored for the given index in the list.
	 */
	public ServerData get(int index) {
		return (ServerData)this.serverList.get(index);
	}

	@Nullable
	public ServerData get(String ip) {
		for (ServerData serverData : this.serverList) {
			if (serverData.ip.equals(ip)) {
				return serverData;
			}
		}

		for (ServerData serverDatax : this.hiddenServerList) {
			if (serverDatax.ip.equals(ip)) {
				return serverDatax;
			}
		}

		return null;
	}

	@Nullable
	public ServerData unhide(String ip) {
		for (int i = 0; i < this.hiddenServerList.size(); i++) {
			ServerData serverData = (ServerData)this.hiddenServerList.get(i);
			if (serverData.ip.equals(ip)) {
				this.hiddenServerList.remove(i);
				this.serverList.add(serverData);
				return serverData;
			}
		}

		return null;
	}

	public void remove(ServerData serverData) {
		if (!this.serverList.remove(serverData)) {
			this.hiddenServerList.remove(serverData);
		}
	}

	public void add(ServerData server, boolean hidden) {
		if (hidden) {
			this.hiddenServerList.add(0, server);

			while (this.hiddenServerList.size() > 16) {
				this.hiddenServerList.remove(this.hiddenServerList.size() - 1);
			}
		} else {
			this.serverList.add(server);
		}
	}

	/**
	 * Counts the number of ServerData instances in the list.
	 */
	public int size() {
		return this.serverList.size();
	}

	/**
	 * Takes two list indexes, and swaps their order around.
	 */
	public void swap(int pos1, int pos2) {
		ServerData serverData = this.get(pos1);
		this.serverList.set(pos1, this.get(pos2));
		this.serverList.set(pos2, serverData);
		this.save();
	}

	public void replace(int index, ServerData server) {
		this.serverList.set(index, server);
	}

	private static boolean set(ServerData server, List<ServerData> serverList) {
		for (int i = 0; i < serverList.size(); i++) {
			ServerData serverData = (ServerData)serverList.get(i);
			if (Objects.equals(serverData.name, server.name) && serverData.ip.equals(server.ip)) {
				serverList.set(i, server);
				return true;
			}
		}

		return false;
	}

	public static void saveSingleServer(ServerData server) {
		IO_EXECUTOR.schedule(() -> {
			ServerList serverList = new ServerList(Minecraft.getInstance());
			serverList.load();
			if (!set(server, serverList.serverList)) {
				set(server, serverList.hiddenServerList);
			}

			serverList.save();
		});
	}
}