extras/src/main/java/pw/kaboom/extras/modules/server/ServerCommand.java

package pw.kaboom.extras.modules.server;

import org.bukkit.block.CommandBlock;
import org.bukkit.command.BlockCommandSender;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.minecart.CommandMinecart;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.server.ServerCommandEvent;

public final class ServerCommand implements Listener {
	public static boolean checkExecuteCommand(final String cmd) {
		return ("execute".equalsIgnoreCase(cmd)
											|| "clone".equalsIgnoreCase(cmd)
											|| "data".equalsIgnoreCase(cmd)
											|| "datapack".equalsIgnoreCase(cmd)
											|| "debug".equalsIgnoreCase(cmd)
											|| "fill".equalsIgnoreCase(cmd)
											|| "forceload".equalsIgnoreCase(cmd)
											|| "kick".equalsIgnoreCase(cmd)
											|| "me".equalsIgnoreCase(cmd)
											|| "msg".equalsIgnoreCase(cmd)
											|| "particle".equalsIgnoreCase(cmd)
											|| "reload".equalsIgnoreCase(cmd)
											|| "save-all".equalsIgnoreCase(cmd)
											|| "say".equalsIgnoreCase(cmd)
											|| "setblock".equalsIgnoreCase(cmd)
											|| "spreadplayers".equalsIgnoreCase(cmd)
											|| "stop".equalsIgnoreCase(cmd)
											|| "summon".equalsIgnoreCase(cmd)
											|| "teammsg".equalsIgnoreCase(cmd)
											|| "teleport".equalsIgnoreCase(cmd)
											|| "tell".equalsIgnoreCase(cmd)
											|| "tellraw".equalsIgnoreCase(cmd)
											|| "tm".equalsIgnoreCase(cmd)
											|| "tp".equalsIgnoreCase(cmd)
											|| "w".equalsIgnoreCase(cmd));
	}
	public static String checkCommand(final CommandSender sender, final String command, final boolean isConsoleCommand) {
		final String[] arr = command.split(" ");
		String commandName = arr[0].toLowerCase();

		if (isConsoleCommand) {
			commandName = "/" + arr[0].toLowerCase();
		}

		try {
			switch (commandName) {
				case "/minecraft:execute":
				case "/execute":
					if (arr.length >= 2) {
						int asAtCount = 0;

						for (int i = 1; i < arr.length; i++) {
							if ("run".equalsIgnoreCase(arr[i])) {
								if (i + 1 < arr.length) {
									if (checkExecuteCommand(arr[i + 1])) {
										return "cancel";
									} else if (i + 3 < arr.length
											&& "gamerule".equalsIgnoreCase(arr[i + 1])) {
										if ("randomTickSpeed".equalsIgnoreCase(arr[i + 2])
												&& Double.parseDouble(arr[i + 3]) > 6) {
											return command.replaceFirst("(?i)" + "randomTickSpeed " + arr[i + 3], "randomTickSpeed 6");
										}
									} else if ("give".equalsIgnoreCase(arr[i + 1])) {
										if (Double.parseDouble(arr[arr.length - 1]) > 64) {
											arr[arr.length - 1] = "64";
											return String.join(" ", arr);
										}
									}
								}
								break;
							}

							if ("as".equalsIgnoreCase(arr[i]) || "at".equalsIgnoreCase(arr[i])) {
								asAtCount++;
							}
						}

						if (asAtCount >= 2) {
							return "cancel";
						}
					}
					break;
				case "/minecraft:fill":
				case "/fill":
					if (command.contains("auto")) {
						return command.replace("auto", "[auto]");
					}
				case "/minecraft:gamerule":
				case "/gamerule":
					if (arr.length >= 3) {
						if ("randomTickSpeed".equalsIgnoreCase(arr[1])
								&& Double.parseDouble(arr[2]) > 6) {
							return command.replaceFirst(arr[2], "6");
						}
					}
					break;
				case "/minecraft:give":
				case "/give":
					if (Double.parseDouble(arr[arr.length - 1]) > 64) {
						arr[arr.length - 1] = "64";
						return String.join(" ", arr);
					}
					break;
				case "/minecraft:particle":
				case "/particle":
					if (arr.length >= 10
							&& Double.parseDouble(arr[9]) > 10) {
						arr[9] = "10";
						return String.join(" ", arr);
					}
					break;
				case "/minecraft:spreadplayers":
				case "/spreadplayers":
					if (arr.length >= 5) {
						if (Double.parseDouble(arr[3]) > 0) {
							arr[3] = "0";
						}
						if (Double.parseDouble(arr[4]) < 8) {
							arr[4] = "8";
						}
						if (Double.parseDouble(arr[4]) > 50) {
							arr[4] = "50";
						}
						return String.join(" ", arr);
					}
					break;
				case "/viaversion:viaver":
				case "/viaversion:viaversion":
				case "/viaversion:vvbukkit":
				case "/viaver":
				case "/viaversion":
				case "/vvbukkit":
					if (arr.length >= 2
							&& "debug".equalsIgnoreCase(arr[1])) {
						return "cancel";
					}
					break;
				case "/minecraft:say":
				case "/say":
					for (int i = 0; i < arr.length; i++) {
						if (arr[i].toLowerCase().contains("@")) {
							return "cancel";
						}
					}
					break;
				default:
					break;
			}
		} catch (NumberFormatException exception) {
			// Do nothing
		}

		if (command.contains("distance")) {
			return command.replace("distance=", "").replace("\"distance\"=", "").replace("'distance'=", "");
		}

		return null;
	}

	@EventHandler
	void onServerCommand(final ServerCommandEvent event) {
		final CommandSender sender = event.getSender();

		if (sender instanceof BlockCommandSender) {
			final CommandBlock commandBlock = (CommandBlock) ((BlockCommandSender) sender).getBlock().getState();

			commandBlock.setCommand("");
			commandBlock.update();
		} else if (sender instanceof CommandMinecart) {
			final CommandMinecart commandMinecart = (CommandMinecart) sender;

			commandMinecart.setCommand("");
		}

		final String command = event.getCommand();
		final boolean isConsoleCommand = true;
		final String checkedCommand = checkCommand(sender, command, isConsoleCommand);

		if (checkedCommand != null) {
			if ("cancel".equals(checkedCommand)) {
				event.setCancelled(true);
			} else {
				event.setCommand(checkedCommand);
			}
		}
	}
}