/*
 *  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.repository;

import java.util.Arrays;
import java.util.List;

import com.rapidminer.repository.gui.actions.AbstractRepositoryAction;

/**
 * Declares a condition for {@link AbstractRepositoryAction}. If the conditions are met, the action is shown, otherwise it will not be shown.
 *
 * @author Marco Boeck
 * 
 */
public class RepositoryActionConditionImplStandard implements RepositoryActionCondition {

	/** selection must be of one of the types listed here */
	private final List<Class<?>> requiredSelectionTypeList;
	
	/** selection repository must be of one of the types listed here */
	private final List<Class<?>> requiredSelectionRepositoryTypeList;
	
	
	/**
	 * Creates a new RepositoryActionCondition which can be used to check if the selected {@link Entry}s meet the given conditions.
	 * @param requiredSelectionTypeList a list with {@link Entry} types. Each selected {@link Entry} must be of one of the types on the list or the condition is not met.
	 * @param requiredSelectionRepositoryTypeList a list with {@link Repository} types. Each selected {@link Entry} must be of the types on the list or the condition is not met.
	 */
	public RepositoryActionConditionImplStandard(List<Class<?>> requiredSelectionTypeList, List<Class<?>> requiredSelectionRepositoryTypeList) {
		if (requiredSelectionTypeList == null || requiredSelectionRepositoryTypeList == null) {
			throw new IllegalArgumentException("lists must not be null!");
		}
		this.requiredSelectionTypeList = requiredSelectionTypeList;
		this.requiredSelectionRepositoryTypeList = requiredSelectionRepositoryTypeList;
	}
	
	/**
	 * Creates a new RepositoryActionCondition which can be used to check if the selected {@link Entry}s meet the given conditions.
	 * @param requiredSelectionTypeList a list with {@link Entry} types. Each selected {@link Entry} must be of one of the types on the list or the condition is not met.
	 * @param requiredSelectionRepositoryTypeList a list with {@link Repository} types. Each selected {@link Entry} must be of the types on the list or the condition is not met.
	 */
	public RepositoryActionConditionImplStandard(Class<?>[] requiredSelectionTypes, Class<?>[] requiredSelectionRepositoryTypes) {
		if (requiredSelectionTypes == null || requiredSelectionRepositoryTypes == null) {
			throw new IllegalArgumentException("arrays must not be null!");
		}
		this.requiredSelectionTypeList = Arrays.asList(requiredSelectionTypes);
		this.requiredSelectionRepositoryTypeList = Arrays.asList(requiredSelectionRepositoryTypes);
	}

	@Override
	public boolean evaluateCondition(List<Entry> entryList) {
		if (entryList == null) {
			return false;
		}
		
		for (Entry givenEntry : entryList) {
			
			// make sure each entry's type is in the requiredTypes list, if not condition evaluates to false
			boolean entryTypeConditionMet = requiredSelectionTypeList.isEmpty() ? true : false;
			for (Class<?> requiredEntry : requiredSelectionTypeList) {
				if (requiredEntry.isAssignableFrom(givenEntry.getClass())) {
					entryTypeConditionMet = true;
					break;
				}
			}
			// wrong entry type
			if (!entryTypeConditionMet) {
				return false;
			}
			
			// make sure each entry's repository type is in the requiredRepositoryTypes list, if not condition evaluates to false
			// if the repository condition list is empty, the condition is automatically met
			boolean entryRepositoryConditionMet = requiredSelectionRepositoryTypeList.isEmpty() ? true : false;
			for (Class<?> requiredRepository : requiredSelectionRepositoryTypeList) {
				try {
					if (requiredRepository.isAssignableFrom(givenEntry.getLocation().getRepository().getClass())) {
						entryRepositoryConditionMet = true;
						break;
					}
				} catch (RepositoryException e) {
					return false;
				}
			}
			// wrong repository type
			if (!entryRepositoryConditionMet) {
				return false;
			}
		}
		
		// all conditions have been met, so return true
		return true;
	}
	
}