/*
 *  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.libraries;

import java.util.Collection;
import java.util.LinkedList;
import java.util.List;

import org.w3c.dom.Element;

import com.rapidminer.OperatorLibraryService;
import com.rapidminer.gui.tools.VersionNumber;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorDescription;
import com.rapidminer.operator.ports.metadata.Precondition;
import com.rapidminer.tools.documentation.OperatorDocBundle;
import com.rapidminer.tools.plugin.Plugin;

/**
 * This is the abstract superclass for all {@link OperatorDescription}s that
 * are stored inside an {@link OperatorLibrary}. These provide additional
 * functionality for accessing different versions of these operators.
 * 
 * @author Sebastian Land
 */
public abstract class LibraryOperatorDescription extends OperatorDescription {

    private static final String ATTRIBUTE_KEY = "key";
    private static final String ATTRIBUTE_GROUP_KEY = "group-key";
    private static final String ATTRIBUTE_ICON = "icon";

    private List<VersionNumber> operatorVersions = new LinkedList<VersionNumber>();
    private OperatorLibrary containingLibrary;

    public LibraryOperatorDescription(OperatorLibrary containingLibrary, String fullyQualifiedGroupKey, String key, Class<? extends Operator> clazz, ClassLoader classLoader, String iconName, Plugin provider, OperatorDocBundle bundle, List<VersionNumber> availableVersions) {
        super(fullyQualifiedGroupKey, key, clazz, classLoader, iconName, provider, bundle);
        this.containingLibrary = containingLibrary;
        this.operatorVersions.addAll(availableVersions);
    }

    /**
     * Operator for constructing these descriptions from xml that has been generated with the
     * {@link #writeXML(Element)} method.
     * 
     * Please notice that you have to regularly add all defined operator versions using the {@link #addVersion(VersionNumber)}
     * method.
     */
    public LibraryOperatorDescription(OperatorLibrary operatorLibrary, Element element, Class<? extends Operator> clazz) {
        super(element.getAttribute(ATTRIBUTE_GROUP_KEY), element.getAttribute(ATTRIBUTE_KEY), clazz, clazz.getClassLoader(), element.getAttribute(ATTRIBUTE_ICON), null, operatorLibrary.getDocumentationBundle());
        this.containingLibrary = operatorLibrary;
    }

    /**
     * This returns a list of all defined version numbers.
     */
    public final List<VersionNumber> getOperatorVersions() {
        return operatorVersions;
    }

    /**
     * This adds the given version to the existing numbers of versions.
     * This has to be called by subclasses in order to publish a new version of
     * an operator!
     * This ensures that the listeners of the {@link OperatorLibraryService} will
     * be informed.
     */
    protected final void addVersion(VersionNumber versionNumber) {
        operatorVersions.add(versionNumber);
        OperatorLibraryService.getService().notifiyOperatorChanged(this);
    }
    /**
     * This returns the collection of all Preconditions that exist for the i-th port.
     * It may return an empty collection if no preconditions have been specified.
     */
    public abstract Collection<? extends Precondition> getPortPreconditions(int i);

    /**
     * This method returns the library this description is contained in.
     */
    public OperatorLibrary getLibrary() {
        return containingLibrary;
    }

    /**
     * This method saves all settings into the given element.
     */
    public void writeXML(Element operatorElement) {
        operatorElement.setAttribute(ATTRIBUTE_KEY, getKey());
        operatorElement.setAttribute(ATTRIBUTE_GROUP_KEY, getGroup());
        operatorElement.setAttribute(ATTRIBUTE_ICON, getIconName());
    }
}