/*
 * Created on 07-Aug-2004 by Ryan McNally
 */

package com.speckled.specksim.imp.motion;

import java.util.Random;

import com.ryanm.config.Configurator;
import com.ryanm.config.ValueListener;
import com.ryanm.config.imp.AbstractConfigurator;
import com.ryanm.config.imp.AnnotatedConfigurator;
import com.ryanm.config.imp.ConfigurableType;
import com.speckled.specksim.Speck;
import com.speckled.specksim.SpeckPosition;

/**
 * Models a static field of randomly placed Specks. For a given rng
 * offset and speck index, the same position will always be given
 * 
 * @author ryanm
 */
@ConfigurableType( "Static" )
public class StaticMovementModel extends AbstractMovementModel
{
	/**
	 * Used to generate the positions
	 */
	private Random random = new Random( 63127 );

	private SpeckPosition skew = new SpeckPosition();

	private AbstractConfigurator conf = null;

	/**
	 * Builds a new StaticMovementModel
	 */
	public StaticMovementModel()
	{
		super( "Static" );
	}

	@Override
	protected void initialise()
	{
	}

	@Override
	protected void deinitialise()
	{
	}

	@Override
	protected SpeckPosition computeLocation( Speck speck, float time, int speckIndex, int population )
	{
		random.setSeed( ( speckIndex + 1 ) * rngSeedOffset );

		// throw away the first couple
		random.nextDouble();
		random.nextDouble();

		SpeckPosition o = new SpeckPosition( random );

		if( !skew.isZero() )
		{
			SpeckPosition s = new SpeckPosition( skew );
			o = SpeckPosition.add( o, s );
		}

		return o;
	}

	@Override
	public Configurator getConfigurator()
	{
		if( conf == null )
		{
			conf = AnnotatedConfigurator.buildConfigurator( this );

			Configurator skewConf = new SpeckPosition.Configurator( "Skew", skew );
			conf.addVariable( skewConf );

			ValueListener valueListener = new ValueListener() {
				public void valueChanged( Configurator conf, String name )
				{
					clearCache();
				}
			};
			conf.addValueListener( valueListener, true );
		}

		return conf;
	}

}