CommandSystem.java

/*
 * This file is part of Foxbot.
 *
 *     Foxbot is free software: you can redistribute it and/or modify
 *     it under the terms of the GNU General Public License as published by
 *     the Free Software Foundation, either version 3 of the License, or
 *     (at your option) any later version.
 *
 *     Foxbot 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 General Public License for more details.
 *
 *     You should have received a copy of the GNU General Public License
 *     along with Foxbot. If not, see <http://www.gnu.org/licenses/>.
 */

package co.foxdev.foxbot.commands;

import co.foxdev.foxbot.FoxBot;
import org.pircbotx.Channel;
import org.pircbotx.User;
import org.pircbotx.hooks.events.MessageEvent;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class CommandSystem extends Command
{
    private final FoxBot foxbot;
    private final Runtime runtime;

    /**
     * ONLY WORKS ON UNIX SYSTEMS
     * Runs a shell command on the machine running FoxBot and sends the output to the channel.
     * Will only send 3 lines of output unless the -v flag is used.
     * <p/>
     * Usage: .sys [-v] <command>
     */
    public CommandSystem(FoxBot foxbot)
    {
        super("system", "command.system", "sys");
        this.foxbot = foxbot;
        runtime = Runtime.getRuntime();
    }

    @Override
    public void execute(MessageEvent event, String[] args)
    {
        User sender = event.getUser();
        Channel channel = event.getChannel();

        if (args.length > 0)
        {
            StringBuilder command = new StringBuilder();
            boolean verbose = args[0].equals("-v");

            for (int i = verbose ? 1 : 0; i < args.length; i++)
            {
                command.append(args[i]).append(" ");
            }

            try
            {
                Process proc = runtime.exec(command.toString());
                BufferedReader stdInput = new BufferedReader(new InputStreamReader(proc.getInputStream()));
                BufferedReader stdError = new BufferedReader(new InputStreamReader(proc.getErrorStream()));
                // Prevent spam on long results
                int count = 0;
                String line;

                while ((line = stdInput.readLine()) != null)
                {
                    if (!verbose && count >= 3)
                    {
                        channel.send().message("Max output reached. Use -v to show full output.");
                        break;
                    }

                    if (!line.isEmpty())
                    {
                        channel.send().message(line);
                        count++;
                    }
                }

                stdInput.close();

                while ((line = stdError.readLine()) != null)
                {
                    if (!verbose && count >= 3)
                    {
                        channel.send().message("Max output reached. Use -v to show full output.");
                        break;
                    }

                    if (!line.isEmpty())
                    {
                        channel.send().message(line);
                        count++;
                    }
                }

                stdError.close();
                proc.destroy();
            }
            catch (IOException ex)
            {
                foxbot.getLogger().error("Error occurred while executing system command", ex);
            }

            return;
        }

        sender.send().notice(String.format("Wrong number of args! Use %ssystem [-v] <command>", foxbot.getConfig().getCommandPrefix()));
    }
}