/*
 *  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.ports.metadata;

import com.rapidminer.example.set.ConditionCreationException;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.SimpleProcessSetupError;
import com.rapidminer.operator.ProcessSetupError.Severity;
import com.rapidminer.operator.ports.InputPort;
import com.rapidminer.operator.ports.OutputPort;
import com.rapidminer.operator.tools.AttributeSubsetSelector;
import com.rapidminer.parameter.UndefinedParameterError;

/**
 * 
 * @author Sebastian Land
 *
 */
public class AttributeSubsetPassThroughRule extends ExampleSetPassThroughRule {

	private final Operator operator;
	private final boolean keepSpecialIfNotIncluded;
	private final AttributeSubsetSelector selector;

	public AttributeSubsetPassThroughRule(InputPort inputPort, OutputPort outputPort, Operator operator, boolean keepSpecialIfNotIncluded) {
		super(inputPort, outputPort, SetRelation.EQUAL);
		this.operator = operator;
		this.keepSpecialIfNotIncluded = keepSpecialIfNotIncluded;
		this.selector = new AttributeSubsetSelector(operator, inputPort);
	}


	@Override
	public ExampleSetMetaData modifyExampleSet(ExampleSetMetaData metaData) {
		// checking if condition creation works
		try {
			AttributeSubsetSelector.createCondition(operator.getParameterAsString(AttributeSubsetSelector.PARAMETER_FILTER_TYPE), operator);
		} catch (UndefinedParameterError e) {
			// a standard error is already thrown
		} catch (ConditionCreationException e) {
			try {
				operator.addError(new SimpleProcessSetupError(Severity.ERROR, operator.getPortOwner(), "attribute_filter_condition_error", operator.getParameterAsString(AttributeSubsetSelector.PARAMETER_FILTER_TYPE)));
			} catch (UndefinedParameterError e1) {
				// a standard error is already thrown
			}
		}		
		ExampleSetMetaData result = selector.getMetaDataSubset(metaData, keepSpecialIfNotIncluded);
		return result;
	}
}