package pl.wroc.pwr.imagechannel.basic;

import pl.wroc.pwr.IOperator;
import pl.wroc.pwr.imagechannel.IImageChannel;
import pl.wroc.pwr.imagechannel.factory.ImageChannelFactory;

public class FastSimpleScale implements IOperator< IImageChannel > {
	private IImageChannel inputChannel;
	private int newX;
	private int newY;

	public FastSimpleScale( IImageChannel inputChannel, int x, int y ) {
		this.inputChannel = inputChannel;
		this.newX = x;
		this.newY = y;
	}

	public IImageChannel apply( ) {
		if ( this.inputChannel == null ) {
			return null;
		}

		IImageChannel outputChannel = new ImageChannelFactory( this.newX, this.newY ).apply();
		double scaleX = this.inputChannel.getXSize( ) / ( double )this.newX;
		double scaleY = this.inputChannel.getYSize( ) / ( double )this.newY;

		for ( int x = 0; x < this.newX; x++ ) {
			for ( int y = 0; y < this.newY; y++ ) {
				int posX = ( int )( x * scaleX );
				int posY = ( int )( y * scaleY );
				outputChannel.setValue( x, y, this.inputChannel.getValue( posX, posY ) );
			}
		}
		return outputChannel;
	}

	public void setNewX(int newX) {
		this.newX = newX;
	}

	public void setNewY(int newY) {
		this.newY = newY;
	}
}