SkinChanger Source Code

/*
 * MIT License
 *
 * Copyright (c) 2016
 *
 * 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.
 */

package net.projectbudder.skinchanger;

import java.lang.reflect.Field;
import java.net.URL;
import java.net.URLConnection;
import java.util.HashMap;
import java.util.Scanner;
import java.util.UUID;

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.command.Command;
import org.bukkit.command.CommandExecutor;
import org.bukkit.command.CommandSender;
import org.bukkit.craftbukkit.v1_9_R2.entity.CraftPlayer;
import org.bukkit.entity.Player;
import org.bukkit.event.Listener;
import org.bukkit.plugin.java.JavaPlugin;
import org.json.simple.JSONArray;
import org.json.simple.JSONObject;
import org.json.simple.parser.JSONParser;

import com.mojang.authlib.GameProfile;
import com.mojang.authlib.properties.Property;

import net.minecraft.server.v1_9_R2.MinecraftServer;
import net.minecraft.server.v1_9_R2.PacketPlayOutEntityDestroy;
import net.minecraft.server.v1_9_R2.PacketPlayOutNamedEntitySpawn;
import net.minecraft.server.v1_9_R2.PacketPlayOutPlayerInfo;
import net.minecraft.server.v1_9_R2.PacketPlayOutPlayerInfo.EnumPlayerInfoAction;

/**
 * @author Jitse3301
 * @since 05.11.2016
 */

public class SkinChanger extends JavaPlugin implements CommandExecutor, Listener {

    private SkinChanger plugin = this;
    private HashMap<UUID, PlayerSkin> profiles = new HashMap<UUID, PlayerSkin>();

    @Override
    public void onEnable() { getCommand("disguise").setExecutor(this); getCommand("undisguise").setExecutor(this); }
    public SkinChanger getMain() { return plugin; }

    public boolean onCommand(CommandSender sender, Command command, String label, final String[] args) {
        if (sender instanceof Player) {
            Player player = (Player) sender;
            if(command.getName().equalsIgnoreCase("disguise")){
                if (args.length == 0) player.sendMessage(ChatColor.RED + "Usage: /skin <playername>");
                else {
                    if(profiles.get(player.getUniqueId()) != null) {
                        profiles.get(player.getUniqueId()).reset();
                        profiles.remove(player.getUniqueId());
                        Bukkit.getScheduler().runTaskLater(getMain(), () -> {
                            Player target = Bukkit.getPlayer(args[0]);
                            if (target != null) {
                                setSkin(target.getUniqueId(), player, target.getName());
                                player.setDisplayName(target.getName());
                                player.setPlayerListName(target.getName());
                            } else {
                                final UUID uuid = getUUID(args[0]);
                                if (uuid != null) {
                                    getServer().getScheduler().runTask(getMain(), () -> { setSkin(uuid, player, args[0]); });
                                    player.setDisplayName(args[0]);
                                    player.setPlayerListName(args[0]);
                                } else sender.sendMessage(ChatColor.RED + args[0] + " is not a real playername!");
                            }
                        }, 75);
                    } else{
                        Player target = Bukkit.getPlayer(args[0]);
                        if (target != null) {
                            setSkin(target.getUniqueId(), player, target.getName());
                            player.setDisplayName(target.getName());
                            player.setPlayerListName(target.getName());
                        } else {
                            final UUID uuid = getUUID(args[0]);
                            if (uuid != null) {
                                getServer().getScheduler().runTask(getMain(), () -> { setSkin(uuid, player, args[0]); });
                                player.setDisplayName(args[0]);
                                player.setPlayerListName(args[0]);
                            } else sender.sendMessage(ChatColor.RED + args[0] + " is not a real playername!");
                        }
                    }
                }
            }
            else if(command.getName().equalsIgnoreCase("undisguise")){
                if(profiles.containsKey(player.getUniqueId())){
                    profiles.get(player.getUniqueId()).reset();
                    profiles.remove(player.getUniqueId());
                } else{
                    player.sendMessage(ChatColor.RED + "You are still yourself!");
                }
            }
        }
        return true;
    }

    @SuppressWarnings("resource")
    public void setSkin(final UUID uuid, final Player player, String name) {
        if (uuid != null) {
            player.sendMessage(ChatColor.RED + "Loading in your new skin, please wait...");
            final String uuidString = uuid.toString().replace("-", "");
            getServer().getScheduler().runTaskAsynchronously(getMain(), () -> {
                try {
                    URLConnection conn = new URL("https://sessionserver.mojang.com/session/minecraft/profile/" + uuidString + "?unsigned=false").openConnection();
                    String json = new Scanner(conn.getInputStream(), "UTF-8").useDelimiter("\\A").next();
                    JSONArray properties = (JSONArray) ((JSONObject) new JSONParser().parse(json)).get("properties");
                    for (Object o : properties) {
                        JSONObject property = (JSONObject) o;
                        if ("textures".equals(property.get("name"))) {
                            final PlayerSkin loaded = new PlayerSkin(plugin, player, name, (String) property.get("value"), property.containsKey("signature") ? (String) property.get("signature") : null);
                            profiles.put(player.getUniqueId(), loaded);
                            getServer().getScheduler().runTask(SkinChanger.this, () -> { loaded.apply(); });
                            break;
                        }
                    }
                } catch (Exception e) { player.sendMessage(ChatColor.RED + "An error occured while changing your profile. (Error: " + e.getMessage() + ")"); return; }
            });
        }
    }

    public UUID UUIDfromString(String string) {
        if (string.charAt(8) != '-') string = string.substring(0, 8) + '-' + string.substring(8);
        if (string.charAt(13) != '-') string = string.substring(0, 13) + '-' + string.substring(13);
        if (string.charAt(18) != '-') string = string.substring(0, 18) + '-' + string.substring(18);
        if (string.charAt(23) != '-') string = string.substring(0, 23) + '-' + string.substring(23);
        return UUID.fromString(string);
    }

    @SuppressWarnings("resource")
    public UUID getUUID(String string) {
        try { return UUIDfromString((String) ((JSONObject) new JSONParser().parse(new Scanner(new URL("https://api.mojang.com/users/profiles/minecraft/" + string).openConnection().getInputStream(), "UTF-8").useDelimiter("\\A").next())).get("id"));
        } catch (Exception e) { return null; }
    }

    class PlayerSkin {

        private static final String FIELD = "bS";

        private SkinChanger plugin;
        private Player player;
        private String newname, value, signature;
        private GameProfile oldprofile;
        public PlayerSkin(SkinChanger plugin, Player player, String newname, String value, String signature) {
            this.plugin = plugin;
            this.player = player;
            this.newname = newname;
            this.value = value;
            this.signature = signature;
            this.oldprofile = ((CraftPlayer)player).getProfile();
        }

        @SuppressWarnings("deprecation")
        public void apply() {
            CraftPlayer cp = (CraftPlayer) player;
            for (Player online : Bukkit.getOnlinePlayers()) online.hidePlayer(player);
            try {
                GameProfile gp = new GameProfile(player.getUniqueId(), newname);
                gp.getProperties().get("textures").clear();
                gp.getProperties().get("textures").add(new Property("textures", value, signature));

                Field field = cp.getHandle().getClass().getSuperclass().getDeclaredField(FIELD);
                field.setAccessible(true);
                field.set(cp.getHandle(), gp);
                field.setAccessible(false);
            } catch (Exception e) { player.sendMessage(ChatColor.RED + "An error occured while changing your profile."); return; }

            Bukkit.getScheduler().runTask(plugin, () -> {
                cp.getHandle().playerConnection.sendPacket(new PacketPlayOutPlayerInfo(EnumPlayerInfoAction.REMOVE_PLAYER, cp.getHandle()));
                Bukkit.getScheduler().runTaskLater(plugin, () -> {
                    Bukkit.getOnlinePlayers().stream().filter(p -> p.getUniqueId() != player.getUniqueId()).forEach(p -> {
                        CraftPlayer cp2 = ((CraftPlayer) player);
                        cp2.getHandle().playerConnection.sendPacket(new PacketPlayOutEntityDestroy(player.getEntityId()));
                        cp2.getHandle().playerConnection.sendPacket(new PacketPlayOutNamedEntitySpawn(cp.getHandle()));
                        Bukkit.getServer().getScheduler().runTask(plugin, () -> p.hidePlayer(player));
                        Bukkit.getServer().getScheduler().runTaskLater(plugin, () -> p.showPlayer(player), 10);
                    });
                    cp.getHandle().playerConnection.sendPacket(new PacketPlayOutPlayerInfo(EnumPlayerInfoAction.ADD_PLAYER, cp.getHandle()));
                    player.sendMessage(ChatColor.YELLOW + "Your skin has been succesfully changed to " + newname + ".");
                }, 15);

                MinecraftServer.getServer().getPlayerList().moveToWorld(cp.getHandle(), player.getWorld().getEnvironment().getId(), true, player.getLocation(), false);
            });
        }

        @SuppressWarnings("deprecation")
        public void reset(){
            player.setDisplayName(oldprofile.getName());
            player.setPlayerListName(oldprofile.getName());
            CraftPlayer cp = (CraftPlayer) player;
            player.sendMessage(ChatColor.GREEN + "Resetting your profile, please wait...");
            for (Player online : Bukkit.getOnlinePlayers()) online.hidePlayer(player);
            try {
                Field field = cp.getHandle().getClass().getSuperclass().getDeclaredField(FIELD);
                field.setAccessible(true);
                field.set(cp.getHandle(), oldprofile);
                field.setAccessible(false);
            } catch (Exception e) { player.sendMessage(ChatColor.RED + "An error occured while changing your profile back."); return; }

            Bukkit.getScheduler().runTask(plugin, () -> {
                cp.getHandle().playerConnection.sendPacket(new PacketPlayOutPlayerInfo(EnumPlayerInfoAction.REMOVE_PLAYER, cp.getHandle()));
                Bukkit.getScheduler().runTaskLater(plugin, () -> {
                    Bukkit.getOnlinePlayers().stream().filter(p -> p.getUniqueId() != player.getUniqueId()).forEach(p -> {
                        CraftPlayer cp2 = ((CraftPlayer) player);
                        cp2.getHandle().playerConnection.sendPacket(new PacketPlayOutEntityDestroy(player.getEntityId()));
                        cp2.getHandle().playerConnection.sendPacket(new PacketPlayOutNamedEntitySpawn(cp.getHandle()));
                        Bukkit.getServer().getScheduler().runTask(plugin, () -> p.hidePlayer(player));
                        Bukkit.getServer().getScheduler().runTaskLater(plugin, () -> p.showPlayer(player), 10);
                    });
                    cp.getHandle().playerConnection.sendPacket(new PacketPlayOutPlayerInfo(EnumPlayerInfoAction.ADD_PLAYER, cp.getHandle()));
                    player.sendMessage(ChatColor.GREEN + "Successfully reset your profile.");
                }, 15);

                MinecraftServer.getServer().getPlayerList().moveToWorld(cp.getHandle(), player.getWorld().getEnvironment().getId(), true, player.getLocation(), false);
            });
        }
    }
}