/*
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.facebook.presto.cassandra;

import org.testng.annotations.Test;

import java.math.BigInteger;

import static java.math.BigInteger.ONE;
import static java.math.BigInteger.ZERO;
import static org.testng.Assert.assertEquals;

public class TestRandomPartitionerTokenRing
{
    private static final RandomPartitionerTokenRing tokenRing = RandomPartitionerTokenRing.INSTANCE;

    @Test
    public void testGetRingFraction()
            throws Exception
    {
        assertEquals(tokenRing.getTokenCountInRange("0", "1"), ONE);
        assertEquals(tokenRing.getTokenCountInRange("0", "200"), new BigInteger("200"));
        assertEquals(tokenRing.getTokenCountInRange("0", "10"), new BigInteger("10"));
        assertEquals(tokenRing.getTokenCountInRange("1", "11"), new BigInteger("10"));
        assertEquals(tokenRing.getTokenCountInRange("0", "0"), ZERO);
        assertEquals(tokenRing.getTokenCountInRange("-1", "-1"), BigInteger.valueOf(2).pow(127).add(ONE));
        assertEquals(tokenRing.getTokenCountInRange("1", "0"), BigInteger.valueOf(2).pow(127));
    }

    @Test
    public void testGetTokenCountInRange()
            throws Exception
    {
        assertEquals(tokenRing.getRingFraction("0", "0"), 0.0, 0.001);
        assertEquals(tokenRing.getRingFraction("1", "0"), 1.0, 0.001);
        assertEquals(tokenRing.getRingFraction("-1", "-1"), 1.0, 0.001);
        assertEquals(tokenRing.getRingFraction("0", BigInteger.valueOf(2).pow(126).toString()), 0.5, 0.001);
        assertEquals(tokenRing.getRingFraction(BigInteger.valueOf(2).pow(126).toString(), BigInteger.valueOf(2).pow(127).toString()), 0.5, 0.001);
        assertEquals(tokenRing.getRingFraction("0", BigInteger.valueOf(2).pow(126).toString()), 0.5, 0.001);
        assertEquals(tokenRing.getRingFraction("0", BigInteger.valueOf(2).pow(127).toString()), 1.0, 0.001);
    }
}
