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

import java.util.Arrays;

import net.imglib2.Dimensions;
import net.imglib2.algorithm.fft2.FFTMethods;
import net.imglib2.util.Pair;
import net.imglib2.util.ValuePair;

import org.scijava.function.Functions;

/**
 * Op that calculates FFT sizes.
 *
 * @author Brian Northan
 * @implNote op names='filter.fftSize'
 */
public class ComputeFFTSize implements
	Functions.Arity5<Dimensions, long[], long[], Boolean, Boolean, Pair<long[], long[]>>
{

	/**
	 * TODO
	 *
	 * @param inputDimensions
	 * @param paddedSize
	 * @param fftSize
	 * @param forward
	 * @param fast
	 * @return the outputs
	 */
	@Override
	public Pair<long[], long[]> apply(Dimensions inputDimensions,
		long[] paddedSize, long[] fftSize, Boolean forward, Boolean fast)
	{

        var paddedOutput = Arrays.copyOf(paddedSize, paddedSize.length);
        var fftOutput = Arrays.copyOf(fftSize, fftSize.length);

		if (fast && forward) {

			FFTMethods.dimensionsRealToComplexFast(inputDimensions, paddedOutput,
				fftOutput);

		}
		else if (!fast && forward) {
			FFTMethods.dimensionsRealToComplexSmall(inputDimensions, paddedOutput,
				fftOutput);

		}
		if (fast && !forward) {

			FFTMethods.dimensionsComplexToRealFast(inputDimensions, paddedOutput,
				fftOutput);

		}
		else if (!fast && !forward) {

			FFTMethods.dimensionsComplexToRealSmall(inputDimensions, paddedOutput,
				fftOutput);

		}

		return new ValuePair<>(paddedOutput, fftOutput);

	}

}
