/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2008 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.example.set;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import com.rapidminer.example.Attribute;
import com.rapidminer.example.Example;
import com.rapidminer.example.ExampleSet;


/**
 * The condition is fulfilled if an attribute has a value equal to, not equal to,
 * less than, ... a given value. This filter can be constructed from several conditions
 * of the class {@link AttributeValueFilterSingleCondition} which must all be fulfilled.
 * 
 * @author Ingo Mierswa
 * @version $Id: AttributeValueFilter.java,v 1.5 2008/05/09 19:22:49 ingomierswa Exp $
 */
public class AttributeValueFilter implements Condition {

    private static final long serialVersionUID = 6977275837081172924L;
    
	private static final int AND = 0;
    private static final int OR  = 1;
    
    /** The list of all single conditions. */
    private List<AttributeValueFilterSingleCondition> conditions = new LinkedList<AttributeValueFilterSingleCondition>();

    private int combinationMode = AND;
    
	/**
	 * Creates a new AttributeValueFilter. If attribute is not nominal, value
	 * must be a number.
	 */
	public AttributeValueFilter(Attribute attribute, int comparisonType, String value) {
		addCondition(attribute, comparisonType, value);
	}

	/**
	 * Constructs an AttributeValueFilter for a given {@link ExampleSet} from a
	 * parameter string
	 * 
	 * @param parameterString
	 *            Must be of the form attribute1 R1 value1 RR attribute2 R2 value2 RR ..., 
     *            where Ri is one out of =, != or <>, <, >, <=, and >= and all RR must 
     *            be either || for OR or && for AND.
	 */
	public AttributeValueFilter(ExampleSet exampleSet, String parameterString) {
		if ((parameterString == null) || (parameterString.length() == 0))
			throw new IllegalArgumentException("Parameter string must not be empty!");

        String[] splitted = parameterString.split("\\|\\|");
        if (splitted.length > 1) {
            for (String condition : splitted) {
                condition = condition.trim();
                addCondition(new AttributeValueFilterSingleCondition(exampleSet, condition));
            }
            this.combinationMode = OR;
        } else {
            splitted = parameterString.split("\\&\\&");
            if (splitted.length > 1) {
                for (String condition : splitted) {
                    condition = condition.trim();
                    addCondition(new AttributeValueFilterSingleCondition(exampleSet, condition));
                }
                this.combinationMode = AND;
            } else {
                addCondition(new AttributeValueFilterSingleCondition(exampleSet, parameterString));
                this.combinationMode = AND;
            }
        }
	}

	private void addCondition(Attribute attribute, int comparisonType, String value) {
        addCondition(new AttributeValueFilterSingleCondition(attribute, comparisonType, value));
	}

    private void addCondition(AttributeValueFilterSingleCondition condition) {
        conditions.add(condition);
    }
    
    /**
     * Since the condition cannot be altered after creation we can just return
     * the condition object itself.
     * 
     * @deprecated Conditions should not be able to be changed dynamically and hence there is no need for a copy
     */
    @Deprecated
    public Condition duplicate() {
        return this;
    }
    
	public String toString() {
		return conditions.toString();
	}

	/** Returns true if all conditions are fulfilled for the given example. */
	public boolean conditionOk(Example e) {
	    Iterator<AttributeValueFilterSingleCondition> i = conditions.iterator();
        while (i.hasNext()) {
            AttributeValueFilterSingleCondition condition = i.next();
            if (combinationMode == AND) {
                if (!condition.conditionOk(e))
                    return false;
            } else {
                if (condition.conditionOk(e))
                    return true;
            }
        }
        if (combinationMode == AND) {
            return true;
        } else {
            return false;
        }
	}
}