/*
 *  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.learner.functions.neuralnet;

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

/**
 * The base node for reading the data from examples and feeding it into the
 * neural net.
 * 
 * @author Ingo Mierswa
 */
public class InputNode extends Node {

	private static final long serialVersionUID = -7509629595651602261L;

	private Attribute attribute;

	private double attributeRange;
	
	private double attributeBase;
	
	private boolean normalize;
	
	
	public InputNode(String nodeName) {
		super(nodeName, INPUT, INPUT);
	}
	
	public void setAttribute(Attribute attribute, double attributeRange, double attributeBase, boolean normalize) {
		this.attribute      = attribute;
		this.attributeRange = attributeRange;
		this.attributeBase  = attributeBase;
		this.normalize      = normalize;
	}

	@Override
	public double calculateValue(boolean shouldCalculate, Example example) {
		if (Double.isNaN(currentValue) && shouldCalculate) {
			double value = example.getValue(attribute);
			if (Double.isNaN(value)) {
				currentValue = 0;
			} else {
				if (normalize) {
					if (attributeRange != 0) {
						currentValue = (value - attributeBase) / attributeRange;
					} else {
						currentValue = value - attributeBase;
					}
				} else {
					currentValue = value;
				}
			}
		}
		return currentValue;
	}

	@Override
	public double calculateError(boolean shouldCalculate, Example example) {
		if (!Double.isNaN(currentValue) && Double.isNaN(currentError) && shouldCalculate) {
			currentError = 0;
			for (int i = 0; i < outputNodes.length; i++) {
				currentError += outputNodes[i].calculateError(true, example);
			}
		}
		return currentError;
	}

	public Attribute getAttribute() {
		return attribute;
	}

	public double getAttributeRange() {
		return attributeRange;
	}

	public double getAttributeBase() {
		return attributeBase;
	}

	public boolean isNormalize() {
		return normalize;
	}

	public double getCurrentValue()
	{
		return currentValue;
	}
}