/**
 * 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 java.util.ArrayList;
import java.util.List;

import org.w3c.dom.Element;
import org.w3c.dom.Node;

import com.rapidminer.tools.XMLException;


/**
 * A parameter type for files. Operators ask for the selected file with
 * {@link com.rapidminer.operator.Operator#getParameterAsFile(String)}. The extension should be
 * defined without the point (separator).
 *
 * @author Ingo Mierswa, Simon Fischer
 */
public class ParameterTypeFile extends ParameterTypeString {

	private static final long serialVersionUID = -1350352634043084406L;

	private static final String ATTRIBUTE_EXTENSION_ELEMENT = "extension";
	private static final String ATTRIBUTE_EXTENSION_ATTRIBUTE = "value";

	private String[] extensions = null;
	private boolean addAllFileExtensionsFilter = false;

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

		List<String> exts = new ArrayList<String>();
		for (int i = 0; i < element.getChildNodes().getLength(); i++) {
			Node extensionNode = element.getChildNodes().item(i);
			if (extensionNode instanceof Element) {
				Element extensionElement = (Element) extensionNode;
				if (extensionElement.getNodeName().equals(ATTRIBUTE_EXTENSION_ELEMENT)) {
					exts.add(extensionElement.getAttribute(ATTRIBUTE_EXTENSION_ATTRIBUTE));
				}
			}
		}
		if (!exts.isEmpty()) {
			extensions = exts.toArray(new String[exts.size()]);
		}
	}

	/**
	 * Creates a new parameter type for files with the given extension. If the extension is null no
	 * file filters will be used. If the parameter is not optional, it is set to be not expert.
	 */
	public ParameterTypeFile(String key, String description, boolean optional, String[] extensions) {
		super(key, description, null);
		setOptional(optional);
		this.extensions = extensions;
	}

	/**
	 * Creates a new parameter type for files with the given extension. If the extension is null no
	 * file filters will be used. If the parameter is not optional, it is set to be not expert.
	 */
	public ParameterTypeFile(String key, String description, String extension, boolean optional) {
		super(key, description, null);
		setOptional(optional);
		this.extensions = new String[] { extension };
	}

	/**
	 * Creates a new parameter type for file with the given extension. If the extension is null no
	 * file filters will be used. The parameter will be optional.
	 */
	public ParameterTypeFile(String key, String description, String extension, String defaultFileName) {
		super(key, description, defaultFileName);
		this.extensions = new String[] { extension };
	}

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

	public String getExtension() {
		return extensions[0];
	}

	public String[] getExtensions() {
		return extensions;
	}

	public String[] getKeys() {
		String[] keys = new String[extensions.length];
		for (int i = 0; i < extensions.length; i++) {
			keys[i] = getKey();
		}
		return keys;
	}

	public void setExtension(String extension) {
		this.extensions[0] = extension;
	}

	public void setExtensions(String[] extensions) {
		this.extensions = extensions;
	}

	/**
	 * @param addAllFileFormatsFilter
	 *            defines whether a filter for all file extension should be added as default filter
	 *            for the file chooser dialog. This makes most sense for file reading operations
	 *            that allow to read files with multiple file extensions. For file writing
	 *            operations it is not recommended as the new filter will not add the correct file
	 *            ending when entering the path of a file that does not exist.
	 */
	public void setAddAllFileExtensionsFilter(boolean addAllFileFormatsFilter) {
		this.addAllFileExtensionsFilter = addAllFileFormatsFilter;
	}

	/**
	 * @return whether a filter all with supported file extensions should be added as default filter
	 *         for the file chooser dialog
	 */
	public boolean isAddAllFileExtensionsFilter() {
		return addAllFileExtensionsFilter;
	}

	@Override
	public String getRange() {
		return "filename";
	}

	@Override
	protected void writeDefinitionToXML(Element typeElement) {
		super.writeDefinitionToXML(typeElement);
		if (extensions != null) {
			for (String extension : extensions) {
				Element extensionElement = typeElement.getOwnerDocument().createElement(ATTRIBUTE_EXTENSION_ELEMENT);
				extensionElement.setAttribute(ATTRIBUTE_EXTENSION_ATTRIBUTE, extension);
				typeElement.appendChild(extensionElement);
			}
		}
	}

}