/**
 * Copyright (C) 2001-2017 by RapidMiner and the contributors
 * 
 * Complete list of developers available at our web site:
 * 
 * http://rapidminer.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.parameter;

import com.rapidminer.io.process.XMLTools;
import com.rapidminer.tools.XMLException;

import org.w3c.dom.Element;


/**
 * A parameter type for String values. Operators ask for the value with
 * {@link com.rapidminer.operator.Operator#getParameterAsString(String)}.
 * 
 * @author Ingo Mierswa, Simon Fischer
 */
public class ParameterTypeString extends ParameterTypeSingle {

	private static final long serialVersionUID = 6451584265725535856L;

	private static final String ELEMENT_DEFAULT = "Default";

	private String defaultValue = null;

	public ParameterTypeString(Element element) throws XMLException {
		super(element);

		defaultValue = XMLTools.getTagContents(element, ELEMENT_DEFAULT);
	}

	public ParameterTypeString(String key, String description, boolean optional, boolean expert) {
		this(key, description, optional);
		setExpert(expert);
	}

	public ParameterTypeString(String key, String description, boolean optional) {
		super(key, description);
		this.defaultValue = null;
		setOptional(optional);
	}

	public ParameterTypeString(String key, String description) {
		this(key, description, true);
	}

	public ParameterTypeString(String key, String description, String defaultValue, boolean expert) {
		this(key, description, defaultValue);
		setExpert(expert);
	}

	public ParameterTypeString(String key, String description, String defaultValue) {
		this(key, description);
		this.defaultValue = defaultValue;
	}

	@Override
	public Object getDefaultValue() {
		return defaultValue;
	}

	@Override
	public void setDefaultValue(Object defaultValue) {
		this.defaultValue = (String) defaultValue;
	}

	/** Returns false. */
	@Override
	public boolean isNumerical() {
		return false;
	}

	@Override
	public String getRange() {
		return "string" + (defaultValue != null ? "; default: '" + defaultValue + "'" : "");
	}

	@Override
	protected void writeDefinitionToXML(Element typeElement) {
		if (defaultValue != null) {
			XMLTools.addTag(typeElement, ELEMENT_DEFAULT, defaultValue);
		}
	}
}