/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.operator;

import java.text.MessageFormat;
import java.util.ResourceBundle;

import com.rapidminer.tools.I18N;

/**
 * Exception class whose instances are thrown by instances of the class {@link Operator} or of one of its subclasses.
 * 
 * This exception also allows using i18n keys, but it is not obligatory to do so. Currently only the .short tag will
 * be used, but this should be changed in future, so adding the other descriptions could be wise.
 * 
 * TODO: Change usage to i18n keys.
 * 
 * @author Ingo Mierswa, Simon Fischer, Sebastian Land
 */
public class OperatorException extends Exception {
	private static final long serialVersionUID = 3626738574540303240L;

	private static ResourceBundle messages = I18N.getUserErrorMessagesBundle(); //ErrorBundle();
	private static final MessageFormat formatter = new MessageFormat("");
	
	public OperatorException(String message) {
		super(message);
	}

	public OperatorException(String message, Throwable cause) {
		super(message, cause);
	}

	public OperatorException(String errorKey, Throwable cause, Object...arguments) {
		super(getErrorMessage(errorKey, arguments), cause);
	}
	
	public static String getErrorMessage(String identifier, Object[] arguments) {
		String message = getResourceString(identifier, "short", "No message.");
		try {
			formatter.applyPattern(message);
			String formatted = formatter.format(arguments);
			return formatted;
		} catch (Throwable t) {
			return message;
		}

	}

	/**
	 * This returns a resource message of the internationalized error messages identified by an id. Compared to the
	 * legacy method {@link #getResourceString(int, String, String)} this supports a more detailed identifier. This
	 * makes it easier to ensure extensions don't reuse already defined core errors. It is common sense to add the
	 * extensions namespace identifier as second part of the key, just after error. For example:
	 * error.rmx_web.operator.unusable = This operator {0} is unusable.
	 * 
	 * @param id
	 *            The identifier of the error. "error." will be automatically prepended-
	 * @param key
	 *            The part of the error description that should be shown.
	 * @param deflt
	 *            The default if no resource bundle is available.
	 */
	public static String getResourceString(String id, String key, String deflt) {
		if (messages == null)
			return deflt;
		try {
			return messages.getString("error." + id + "." + key);
		} catch (java.util.MissingResourceException e) {
			return deflt;
		}
	}
}