package it.unimi.dsi.fastutil.longs;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertTrue;
import it.unimi.dsi.fastutil.ints.IntArrays;

import java.util.Random;

import org.junit.Test;

public class LongArraysTest {
	
	private static long[] identity( int n ) {
		final long[] a = new long[ n ];
		while( n-- != 0 ) a[ n ] = n;
		return a;
	}

	@Test
	public void testRadixSort1() {
		long[] t = { 2, 1, 0, 4 };
		LongArrays.radixSort( t );
		for( int i = t.length - 1; i-- != 0; ) assertTrue( t[ i ] <= t[ i + 1 ] );
		
		t = new long[] { 2, -1, 0, -4 };
		LongArrays.radixSort( t );
		for( int i = t.length - 1; i-- != 0; ) assertTrue( t[ i ] <= t[ i + 1 ] );
		
		t = LongArrays.shuffle( identity( 100 ), new Random( 0 ) );
		LongArrays.radixSort( t );
		for( int i = t.length - 1; i-- != 0; ) assertTrue( t[ i ] <= t[ i + 1 ] );

		t = new long[ 100 ];
		Random random = new Random( 0 );
		for( int i = t.length; i-- != 0; ) t[ i ] = random.nextLong();
		LongArrays.radixSort( t );
		for( int i = t.length - 1; i-- != 0; ) assertTrue( t[ i ] <= t[ i + 1 ] );

		t = new long[ 100000 ];
		random = new Random( 0 );
		for( int i = t.length; i-- != 0; ) t[ i ] = random.nextLong();
		LongArrays.radixSort( t );
		for( int i = t.length - 1; i-- != 0; ) assertTrue( t[ i ] <= t[ i + 1 ] );

		t = new long[ 10000000 ];
		random = new Random( 0 );
		for( int i = t.length; i-- != 0; ) t[ i ] = random.nextLong();
		LongArrays.radixSort( t );
		for( int i = t.length - 1; i-- != 0; ) assertTrue( t[ i ] <= t[ i + 1 ] );
	}

	@Test
	public void testRadixSort2() {
		long[][] d = new long[ 2 ][];

		d[ 0 ] = new long[ 10 ];
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = 3 - i % 3;
		d[ 1 ] = LongArrays.shuffle( identity( 10 ), new Random( 0 ) );
		LongArrays.radixSort( d[ 0 ], d[ 1 ] );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );
		
		d[ 0 ] = new long[ 100000 ];
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = 100 - i % 100;
		d[ 1 ] = LongArrays.shuffle( identity( 100000 ), new Random( 6 ) );
		LongArrays.radixSort( d[ 0 ], d[ 1 ] );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );

		d[ 0 ] = new long[ 10 ];
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = i % 3 - 2;
		Random random = new Random( 0 );
		d[ 1 ] = new long[ d[ 0 ].length ];
		for( int i = d.length; i-- != 0; ) d[ 1 ][ i ] = random.nextLong();
		LongArrays.radixSort( d[ 0 ], d[ 1 ] );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );
		
		d[ 0 ] = new long[ 100000 ];
		random = new Random( 0 );
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = random.nextLong();
		d[ 1 ] = new long[ d[ 0 ].length ];
		for( int i = d.length; i-- != 0; ) d[ 1 ][ i ] = random.nextLong();
		LongArrays.radixSort( d[ 0 ], d[ 1 ] );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );

	}

	@Test
	public void testRadixSort() {
		long[][] t = { { 2, 1, 0, 4 } };
		LongArrays.radixSort( t );
		for( int i = t[ 0 ].length - 1; i-- != 0; ) assertTrue( t[ 0 ][ i ] <= t[ 0 ][ i + 1 ] );
		
		t[ 0 ] = LongArrays.shuffle( identity( 100 ), new Random( 0 ) );
		LongArrays.radixSort( t );
		for( int i = t[ 0 ].length - 1; i-- != 0; ) assertTrue( t[ 0 ][ i ] <= t[ 0 ][ i + 1 ] );

		long[][] d = new long[ 2 ][];

		d[ 0 ] = new long[ 10 ];
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = 3 - i % 3;
		d[ 1 ] = LongArrays.shuffle( identity( 10 ), new Random( 0 ) );
		LongArrays.radixSort( d );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );

		
		d[ 0 ] = new long[ 100000 ];
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = 100 - i % 100;
		d[ 1 ] = LongArrays.shuffle( identity( 100000 ), new Random( 6 ) );
		LongArrays.radixSort( d );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );

		d[ 0 ] = new long[ 10 ];
		Random random = new Random( 0 );
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = random.nextLong();
		d[ 1 ] = new long[ d[ 0 ].length ];
		for( int i = d.length; i-- != 0; ) d[ 1 ][ i ] = random.nextLong();
		LongArrays.radixSort( d );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );

		
		d[ 0 ] = new long[ 100000 ];
		random = new Random( 0 );
		for( int i = d[ 0 ].length; i-- != 0; ) d[ 0 ][ i ] = random.nextLong();
		d[ 1 ] = new long[ d[ 0 ].length ];
		for( int i = d.length; i-- != 0; ) d[ 1 ][ i ] = random.nextLong();
		LongArrays.radixSort( d );
		for( int i = d[ 0 ].length - 1; i-- != 0; ) assertTrue( Long.toString( i ) + ": <" + d[ 0 ][ i ] + ", " + d[ 1 ][ i ] + ">, <" + d[ 0 ][ i + 1 ] + ", " +  d[ 1 ][ i + 1 ] + ">", d[ 0 ][ i ] < d[ 0 ][ i + 1 ] || d[ 0 ][ i ] == d[ 0 ][ i + 1 ] && d[ 1 ][ i ] <= d[ 1 ][ i + 1 ] );

	}

	@Test
	public void testStabilize() {
		int[] perm;
		long[] val;
		
		perm = new int[] { 0, 1, 2, 3 };
		val = new long[] { 0, 0, 0, 0 };
		
		LongArrays.stabilize( perm, val );
		assertArrayEquals( new int[] { 0, 1, 2, 3 }, perm );
		
		perm = new int[] { 3, 1, 2, 0 };
		val = new long[] { 0, 0, 0, 0 };
		
		LongArrays.stabilize( perm, val );
		assertArrayEquals( new int[] { 0, 1, 2, 3 }, perm );

		perm = new int[] { 3, 2, 1, 0 };
		val = new long[] { 0, 1, 1, 2 };
		
		LongArrays.stabilize( perm, val );
		assertArrayEquals( new int[] { 3, 1, 2, 0 }, perm );

		perm = new int[] { 3, 2, 1, 0 };
		val = new long[] { 0, 0, 1, 1 };
		
		LongArrays.stabilize( perm, val );
		assertArrayEquals( new int[] { 2, 3, 0, 1 }, perm );

		perm = new int[] { 4, 3, 2, 1, 0 };
		val = new long[] { 1, 1, 0, 0, 0 };
		
		LongArrays.stabilize( perm, val, 1, 3 );
		assertArrayEquals( new int[] { 4, 2, 3, 1, 0 }, perm );
	}
}
