/*
 * #%L
 * Image processing operations for SciJava Ops.
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package org.scijava.ops.image.image.normalize;

import net.imglib2.converter.Converter;
import net.imglib2.type.numeric.RealType;

import org.scijava.function.Computers;

/**
 * Simple {@link UnaryComputerOp} and {@link Converter} to perform a
 * normalization.
 *
 * @author Christian Dietz (University of Konstanz)
 * @author Leon Yang
 */
class NormalizeRealTypeComputer<I extends RealType<I>, O extends RealType<O>>
	implements Computers.Arity1<I, O>, Converter<I, O>
{

	// TODO: should this become an Op?
	private double targetMin, targetMax, sourceMin, factor;

	public NormalizeRealTypeComputer() {}

	public NormalizeRealTypeComputer(final double sourceMin,
		final double sourceMax, final double targetMin, final double targetMax)
	{
		setup(sourceMin, sourceMax, targetMin, targetMax);
	}

	public void setup(final double sourceMin, final double sourceMax,
		final double targetMin, final double targetMax)
	{
		this.sourceMin = sourceMin;
		final var tmp = sourceMax;
		this.targetMin = targetMin;
		this.targetMax = targetMax;

		this.factor = 1.0d / (tmp - this.sourceMin) * (this.targetMax -
			this.targetMin);
	}

	@Override
	public void compute(final I input, final O output) {

		final var res = (input.getRealDouble() - sourceMin) * factor + targetMin;

		if (res > targetMax) {
			output.setReal(targetMax);
		}
		else if (res < targetMin) {
			output.setReal(targetMin);
		}
		else {
			output.setReal(res);
		}
	}

	@Override
	public void convert(I input, O output) {
		compute(input, output);
	}
}
