package jas2.hist;
import java.io.Serializable;
import java.util.Observable;
import java.util.Observer;

public abstract class Fitter extends Observable implements Observer, Runnable, Serializable
{
	public abstract double getChiSquared();
	public abstract double[] getParameterSigmas();
	protected abstract void fit(Fittable1DFunction fa, double[] x, double[] y, double[] sigmaY) throws FitFailed;

	public void fit() throws FitFailed
	{
		if (state != READYTOFIT) throw new FitFailed("Not ready to fit");
		internalFit();
		observeData();
	}
	public synchronized void start()
	{
		if (state == READYTOFIT)
		{
			thread = new Thread(this,"Fit thread");
			thread.start();
		}
	}
	public synchronized void stop()
	{
		if (thread != null) thread.stop();
	}
	public void run()
	{
		try
		{
			internalFit();
			observeData();
		}
		catch (FitFailed x) {}
		finally
		{
			synchronized (this) { thread = null; }
		}
	}
	public synchronized void update(Observable obs, Object arg)
	{
		if (obs == m_data) 
		{
			if (state == FIT) setState(READYTOFIT);
			start();
		}
	}
	public int getState()
	{
		return state;
	}
	private synchronized void observeData()
	{
		if (!observing && m_data instanceof Observable) 
			((Observable) m_data).addObserver(this);
	}
	private synchronized void setState(int state)
	{
		this.state = state;
		setChanged();
		notifyObservers(new FitUpdate(state));
	}
	private synchronized void setState(int state, FitFailed x)
	{
		this.state = state;
		setChanged();
		notifyObservers(new FitUpdate(state,x));
	}
	protected void setPercentComplete(int percent)
	{
		setChanged();
		notifyObservers(new FitUpdate(state,percent));
	}
	private void internalFit() throws FitFailed
	{
		setState(FITTING);
		try
		{
			int n = m_data.getNPoints();
			double[] x = new double[n];
			double[] y = new double[n];
			double[] yerr = new double[n];	

         for (int i=0; i