/*
 *  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.io.process.rules;

import java.util.Collections;
import java.util.List;

import com.rapidminer.gui.tools.VersionNumber;
import com.rapidminer.io.process.XMLImporter;
import com.rapidminer.operator.ExecutionUnit;
import com.rapidminer.operator.Operator;
import com.rapidminer.operator.OperatorCreationException;
import com.rapidminer.operator.meta.OperatorEnabler;
import com.rapidminer.operator.meta.OperatorSelector;
import com.rapidminer.parameter.UndefinedParameterError;
import com.rapidminer.tools.OperatorService;
/**
 * 
 * @author Sebastian Land
 */
public class OperatorEnablerRepairRule extends AbstractGenericParseRule {
	private static final VersionNumber APPLIES_UNTIL = new VersionNumber(5, 0, 0, false, 0, false, 0);
	
	@Override
	public String apply(Operator operator, VersionNumber processVersion, XMLImporter importer) {
		if (operator.getClass().equals(OperatorEnabler.class) && (processVersion == null || processVersion.compareTo(APPLIES_UNTIL) < 0)) {
			OperatorEnabler enabler = (OperatorEnabler) operator;
			Operator selected = null;
			String selectedName;
			try {
				selectedName = enabler.getParameterAsString(OperatorEnabler.PARAMETER_OPERATOR_NAME);
			} catch (UndefinedParameterError e) {
				selectedName = null;
			}
			for (Operator op : enabler.getAllInnerOperators()) {
				if (op.getName().equals(selectedName)) {
					selected = op;
					break;
				}
			}		
			
			OperatorSelector selector;
			try {
				selector = OperatorService.createOperator(OperatorSelector.class);
			} catch (OperatorCreationException e) {
				return "<em class=\"error\">The operator <var>"+enabler.getName()+"</var> (<code>OperatorEnabler</code>) could not be imported: "+e.getMessage()+"</em>";				
			}
			int selectedSubprocess = enabler.getParameterAsBoolean(OperatorEnabler.PARAMETER_ENABLE) ? 0 : 1;
			selector.setParameter(OperatorSelector.PARAMETER_SELECT_WHICH, ""+(selectedSubprocess+1));
			while (!enabler.getSubprocess(0).getOperators().isEmpty()) {				
				Operator child = enabler.getSubprocess(0).getOperators().get(0);
				child.remove();
				selector.getSubprocess(0).addOperator(child.cloneOperator(null, false));
				if (!child.getName().equals(selectedName)) {
					selector.getSubprocess(1).addOperator(child.cloneOperator(null, false));
				}
			}
			
			ExecutionUnit parent = enabler.getExecutionUnit();
			int oldIndex = parent.getOperators().indexOf(enabler);
			enabler.remove();
			selector.rename(enabler.getName());
			parent.addOperator(selector, oldIndex);
			if (selected == null) {
				return "<em class=\"error\">The operator <var>"+enabler.getName()+"</var> (<code>OperatorEnabler</code>) could not be correctly imported since the enabled/disabled child '"+selectedName+"' was not found.</em>";
			} else {				
				return "The operator <var>"+enabler.getName()+"</var> (<code>OperatorEnabler</code>) was replaced by an <code>OperatorSelector</code> where in subprocess "+selectedSubprocess+" the operator <var>"+selected.getName()+"</var> was omitted.";
			}
		} else {
			return null;
		}
	}

	@Override
	public List<String> getApplicableOperatorKeys() {
		return Collections.singletonList("operatorenabler");
	}


}