/***********************************************************************

	This file is part of JavaNPST, a Java library of NonParametric
	Statistical Tests.

	Copyright (C) 2011
	
	J. Derrac (jderrac@decsai.ugr.es)
	S. Garcia (sglopez@ujaen.es)
	F. Herrera (herrera@decsai.ugr.es)

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU 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 General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see http://www.gnu.org/licenses/
  
**********************************************************************/

package javanpst.tests.randomness.runsUpDownTest;

import javanpst.data.structures.sequence.NumericSequence;
import javanpst.distributions.tests.RunsUpDownDistribution;
import javanpst.tests.StatisticalTest;


/**
 * A test based on runs up and down
 * 
 * This tests check randomness of a numeric sequence by 
 * analyzing the changes in direction of its runs (ascending
 * or descending).
 * 
 * A normal approximation is also provided. 
 * 
 * @author Joaqu�n Derrac Rus (jderrac@decsai.ugr.es)
 * @version 1.0
 */
public class RunsUpDownTest extends StatisticalTest{

	/**
	 * Distribution of the test
	 */
	private RunsUpDownDistribution distribution;
	
	/**
	 * Sequence to test
	 */
	private NumericSequence sequence;
	
	/**
	 * Number of runs in the sequence
	 */
	private int runs;
	
	/**
	 * Left tail p-value
	 */
	private double exactLeftTail;
	
	/**
	 * Right tail p-value
	 */
	private double exactRightTail;
	
	/**
	 * Double tail p-value
	 */
	private double exactDoubleTail;
	
	/**
	 * Left tail asymptotic p-value
	 */
	private double asymptoticLeftTail;
	
	/**
	 * Right tail asymptotic p-value
	 */
	private double asymptoticRightTail;
	
	/**
	 * Double tail asymptotic p-value
	 */
	private double asymptoticDoubleTail;
	

	/**
	 * Default builder
	 */
	public RunsUpDownTest(){
		
		distribution=RunsUpDownDistribution.getInstance();
		setReportFormat();
		clearData();
		
	}//end-method
	
	/**
	 * Clears the data stored in the test
	 */
	public void clearData(){
		
		sequence=new NumericSequence();
		
		performed=false;
		dataReady=false;

		runs=0;
		
		exactLeftTail=-1.0;
		exactRightTail=-1.0;
		exactDoubleTail=-1.0;
		
		asymptoticLeftTail=-1.0;
		asymptoticRightTail=-1.0;
		asymptoticDoubleTail=-1.0;
		
	}//end-method
	
	/**
	 * Builder. Load data to test.
	 * 
	 * @param newSequence data to test.
	 */
	public RunsUpDownTest(NumericSequence newSequence){

		setReportFormat();
		distribution=RunsUpDownDistribution.getInstance();
		
		sequence=new NumericSequence(newSequence);
		
		dataReady=true;
		performed=false;
		
	}//end-method
	
	/**
	 * Load data to test.
	 * 
	 * @param newSequence data to test.
	 */
	public void setData(NumericSequence newSequence){
		
		sequence=new NumericSequence(newSequence);

		dataReady=true;
		performed=false;
		
	}//end-method
	
	public void doTest(){
	
		if(!dataReady){		
			System.out.println("Data is not ready");
			return;	
		}
		
		computeRuns();
		
		exactLeftTail=distribution.computeExactProbability(sequence.size(), runs,true);
		exactRightTail=distribution.computeExactProbability(sequence.size(), runs,false);
		exactDoubleTail=Math.min(Math.min(exactLeftTail, exactRightTail)*2.0, 1.0);
		
		asymptoticLeftTail=distribution.computeAsymptoticLeftTailProbability(sequence.size(), runs);
		asymptoticRightTail=distribution.computeAsymptoticRightTailProbability(sequence.size(), runs);
		asymptoticDoubleTail=distribution.computeAsymptoticDoubleTailProbability(sequence.size(), runs);
		
		performed=true;

	}//end-method
	
	/**
	 * Compute the number of runs up and down in the sequence
	 */
	private void computeRuns(){
	
		double lastN;
		double newN;
		boolean ascending;
		
		runs=1;
		
		lastN=sequence.get(0);
		newN=sequence.get(1);
		
		if(lastN<=newN){
			ascending=true;
		}
		else{
			ascending=false;
		}
		
		lastN=newN;
		
		for(int i=2;inewN){
					runs++;
					ascending=false;
				}
			}
			else{
				if(lastN