Utils.java

/**
 * Copyright (C) 2010-2014 Leon Blakey <lord.quackstar at gmail.com>
 *
 * This file is part of PircBotX.
 *
 * PircBotX 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.
 *
 * PircBotX 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
 * PircBotX. If not, see <http://www.gnu.org/licenses/>.
 */
package org.pircbotx;

import com.google.common.base.CharMatcher;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.annotation.Nullable;
import lombok.NonNull;
import org.apache.commons.lang3.StringUtils;
import org.pircbotx.hooks.Event;
import org.pircbotx.hooks.types.GenericMessageEvent;
import org.slf4j.MDC;
import org.slf4j.helpers.MessageFormatter;

/**
 * Useful utilities for internal PircBotX use. Users should not use this class
 * directly
 *
 * @author Leon Blakey
 */
public final class Utils {
	//Do not create instances of this
	private Utils() {
	}

	@SuppressWarnings("unchecked")
	public static void dispatchEvent(PircBotX bot, Event event) {
		bot.getConfiguration().getListenerManager().onEvent(event);
	}

	/**
	 * Try to parse int string, returning -1 if it fails.
	 *
	 * @return The string as an int or -1
	 */
	public static int tryParseInt(String intString, int defaultValue) {
		try {
			return Integer.parseInt(intString);
		} catch (NumberFormatException e) {
			return defaultValue;
		}
	}

	/**
	 * Try to parse long string, returning -1 if it fails.
	 *
	 * @param longString
	 * @return The string as a long or -1
	 */
	public static long tryParseLong(String longString, int defaultValue) {
		try {
			return Long.parseLong(longString);
		} catch (NumberFormatException e) {
			return defaultValue;
		}
	}

	public static <V> V tryGetIndex(List<V> list, int index, V defaultValue) {
		if (index < list.size())
			return list.get(index);
		else
			return defaultValue;
	}

	/**
	 * Gets the message from the event and calls {@link #parseCommand(java.lang.String, java.lang.String)
	 * }
	 *
	 * @see #parseCommand(java.lang.String, java.lang.String)
	 */
	@Nullable
	public static String parseCommand(String expectedPrefix, GenericMessageEvent event) {
		return parseCommand(expectedPrefix, event.getMessage());
	}

	/**
	 * Parse given command, if it starts with the prefix return the line minus
	 * the prefix (the arguments), otherwise return null
	 * <p>
	 * <ul>
	 * <li>parseCommand("?say ", "?say hi everybody") == "hi everybody"</li>
	 * <li>parseCommand("?say ", "?other stuff") == null</li>
	 * <li>parseCommand("?start", "?start") == ""</li>
	 * <li>parseCommand("?start", "?stop") == null</li>
	 * </ul>
	 *
	 * @param expectedPrefix The prefix the command must start with and will be
	 * removed when returned
	 * @param rawCommand Raw input string
	 * @return input string minus the prefix or null
	 */
	@Nullable
	public static String parseCommand(@NonNull String expectedPrefix, @NonNull String rawCommand) {
		if (rawCommand.startsWith(expectedPrefix))
			return rawCommand.substring(expectedPrefix.length());
		return null;
	}

	public static void addBotToMDC(PircBotX bot) {
		MDC.put("pircbotx.id", String.valueOf(bot.getBotId()));
		MDC.put("pircbotx.connectionId", bot.getServerHostname() + "-" + bot.getBotId() + "-" + bot.getConnectionId());
		MDC.put("pircbotx.server", StringUtils.defaultString(bot.getServerHostname()));
		MDC.put("pircbotx.port", String.valueOf(bot.getServerPort()));
	}

	/**
	 * Sends a raw line to the server. Needed so {@link PircBotX#sendRawLineToServer(java.lang.String)
	 * }
	 * can stay protected but still be callable from the org.pircbotx.output
	 * package
	 *
	 * @param bot The bot that sends the raw line
	 * @param rawLine The raw line to send
	 */
	public static void sendRawLineToServer(PircBotX bot, String rawLine) throws IOException {
		bot.sendRawLineToServer(rawLine);
	}

	/**
	 * Sets bot as identified to nickserv. Needed so {@link PircBotX#setNickservIdentified(boolean)
	 * }
	 * can stay protected
	 *
	 * @param bot
	 */
	public static void setNickServIdentified(PircBotX bot) {
		bot.setNickservIdentified(true);
	}

	public static String format(String messagePattern, Object... args) {
		return MessageFormatter.arrayFormat(messagePattern, args).getMessage();
	}

	/**
	 * Tokenize IRC raw input into it's components, keeping the 'sender' and
	 * 'message' fields intact.
	 *
	 * @param input A string in the format [:]item [item] ... [:item [item] ...]
	 * @return List of strings.
	 */
	public static List<String> tokenizeLine(String input) {
		List<String> stringParts = new ArrayList<String>();
		if (input == null || input.length() == 0)
			return stringParts;

		//Heavily optimized string split by space with all characters after :
		//added as a single entry. Under benchmarks, this is faster than 
		//StringTokenizer, String.split, toCharArray, and charAt
		String trimmedInput = CharMatcher.WHITESPACE.trimFrom(input);
		int pos = 0, end;
		while ((end = trimmedInput.indexOf(' ', pos)) >= 0) {
			stringParts.add(trimmedInput.substring(pos, end));
			pos = end + 1;
			if (trimmedInput.charAt(pos) == ':') {
				stringParts.add(trimmedInput.substring(pos + 1));
				return stringParts;
			}
		}
		//No more spaces, add last part of line
		stringParts.add(trimmedInput.substring(pos));
		return stringParts;
	}
}