package pl.wroc.pwr.image.converter;

import pl.wroc.pwr.IOperator;
import pl.wroc.pwr.image.IHSVImage;
import pl.wroc.pwr.image.IRGBImage;
import pl.wroc.pwr.image.model.HSVImage;
import pl.wroc.pwr.image.model.RGBImage;
import pl.wroc.pwr.imagechannel.IImageChannel;

public class HSVtoRGBConverter implements IOperator< IRGBImage >
{
	/**
	 *
	 */
	private static final long serialVersionUID = -399191030084052738L;

	private IHSVImage inputImage;

	public HSVtoRGBConverter(IImageChannel hue, IImageChannel saturation, IImageChannel value) {
		this.inputImage = new HSVImage(hue, saturation, value);
	}

	public HSVtoRGBConverter( IHSVImage image ) {
		this.inputImage = image;
	}

	public void setImage( IHSVImage image )
	{
		this.inputImage = image;
	}

	public IRGBImage apply( )
	{
		IRGBImage outputImage = new RGBImage( this.inputImage.getSize( ) );
		for ( int i = 0; i < this.inputImage.getHueChannel( ).getMaxIndex( ); i++ )
		{
			float saturation = this.inputImage.getSaturationChannel( ).getValue( i );
			float hue = this.inputImage.getHueChannel( ).getValue( i );
			float brightness = this.inputImage.getBrightnessChannel( ).getValue( i );
			float red = 0;
			float green = 0;
			float blue = 0;

			if ( saturation == 0 )
			{
				red = brightness;
				green = brightness;
				blue = brightness;
			}
			else
			{
				if ( hue == 1 )
				{
					hue = 0;
				}
				hue = hue * 6;

				int iHue = ( int )hue;
				float fHue = hue - iHue;

				float p = brightness * ( 1 - saturation );
				float q = brightness * ( 1 - ( saturation * fHue ) );
				float t = brightness * ( 1 - ( saturation * ( 1 - fHue ) ) );

				switch ( iHue )
				{
				case 0:
					red = brightness;
					green = t;
					blue = p;
					break;
				case 1:
					red = q;
					green = brightness;
					blue = p;
					break;
				case 2:
					red = p;
					green = q;
					blue = brightness;
					break;
				case 3:
					red = p;
					green = q;
					blue = brightness;
					break;
				case 4:
					red = t;
					green = p;
					blue = brightness;
					break;
				case 5:
					red = brightness;
					green = p;
					blue = q;
					break;
				}
			}
			outputImage.getRedChannel( ).setValue( i, red );
			outputImage.getGreenChannel( ).setValue( i, green );
			outputImage.getBlueChannel( ).setValue( i, blue );
		}
		return outputImage;
	}
}