import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;
import java.util.*;
import java.util.stream.*;

public class MusicalNoteTest {
	@Test
	public void testTranspose() {
		assertEquals(MusicalNote.transpose(MusicalNote.GSharp, -50000), MusicalNote.C);
	}

	@Test
	public void testFifth() {
		List<MusicalNote> ns = MusicalNote.fifths.apply(true, MusicalNote.ASharp).limit(12).collect(Collectors.toList());
		assertEquals("0", MusicalNote.ASharp, ns.get(0));
		for (int i = 0; i < ns.size() - 1; i++)
			assertEquals((i + 1) + "", MusicalNote.transpose(ns.get(i), 7), ns.get(i + 1));

		ns = MusicalNote.fifths.apply(false, MusicalNote.E).limit(12).collect(Collectors.toList());
		assertEquals("0", MusicalNote.E, ns.get(0));
		for (int i = 0; i < ns.size() - 1; i++)
			assertEquals((i + 1) + "", MusicalNote.transpose(ns.get(i), -7), ns.get(i + 1));
	}

	@Test
	public void testFifthMillionth() {
		assertEquals(Optional.of(MusicalNote.G), MusicalNote.fifths.apply(false, MusicalNote.B).skip(1000000).findFirst());
	}
}