/*
 * Copyright (c) "Neo4j"
 * Neo4j Sweden AB [http://neo4j.com]
 *
 * This file is part of Neo4j.
 *
 * Neo4j is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.neo4j.internal.helpers;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertThrows;

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;

class NumbersTest {
    @Test
    void failSafeCastLongToInt() {
        ArithmeticException exception =
                assertThrows(ArithmeticException.class, () -> Numbers.safeCastLongToInt(Integer.MAX_VALUE + 1L));
        assertEquals("Value 2147483648 is too big to be represented as int", exception.getMessage());
    }

    @Test
    void failSafeCastLongToShort() {
        ArithmeticException exception =
                assertThrows(ArithmeticException.class, () -> Numbers.safeCastLongToShort(Short.MAX_VALUE + 1L));
        assertEquals("Value 32768 is too big to be represented as short", exception.getMessage());
    }

    @Test
    void failSafeCastIntToUnsignedShort() {
        ArithmeticException exception =
                assertThrows(ArithmeticException.class, () -> Numbers.safeCastIntToUnsignedShort(Short.MAX_VALUE << 2));
        assertEquals("Value 131068 is too big to be represented as unsigned short", exception.getMessage());
    }

    @Test
    void failSafeCastLongToByte() {
        ArithmeticException exception =
                assertThrows(ArithmeticException.class, () -> Numbers.safeCastLongToByte(Byte.MAX_VALUE + 1));
        assertEquals("Value 128 is too big to be represented as byte", exception.getMessage());
    }

    @Test
    void failSafeCastIntToShort() {
        ArithmeticException exception =
                assertThrows(ArithmeticException.class, () -> Numbers.safeCastIntToShort(Short.MAX_VALUE + 1));
        assertEquals("Value 32768 is too big to be represented as short", exception.getMessage());
    }

    @Test
    void castLongToInt() {
        Assertions.assertEquals(1, Numbers.safeCastLongToInt(1L));
        Assertions.assertEquals(10, Numbers.safeCastLongToInt(10L));
        Assertions.assertEquals(-1, Numbers.safeCastLongToInt(-1L));
        Assertions.assertEquals(Integer.MAX_VALUE, Numbers.safeCastLongToInt(Integer.MAX_VALUE));
        Assertions.assertEquals(Integer.MIN_VALUE, Numbers.safeCastLongToInt(Integer.MIN_VALUE));
    }

    @Test
    void castLongToShort() {
        Assertions.assertEquals(1, Numbers.safeCastLongToShort(1L));
        Assertions.assertEquals(10, Numbers.safeCastLongToShort(10L));
        Assertions.assertEquals(-1, Numbers.safeCastLongToShort(-1L));
        Assertions.assertEquals(Short.MAX_VALUE, Numbers.safeCastLongToShort(Short.MAX_VALUE));
        Assertions.assertEquals(Short.MIN_VALUE, Numbers.safeCastLongToShort(Short.MIN_VALUE));
    }

    @Test
    void castIntToUnsignedShort() {
        Assertions.assertEquals(1, Numbers.safeCastIntToUnsignedShort(1));
        Assertions.assertEquals(10, Numbers.safeCastIntToUnsignedShort(10));
        Assertions.assertEquals(-1, Numbers.safeCastIntToUnsignedShort((Short.MAX_VALUE << 1) + 1));
    }

    @Test
    void castIntToShort() {
        Assertions.assertEquals(1, Numbers.safeCastIntToShort(1));
        Assertions.assertEquals(10, Numbers.safeCastIntToShort(10));
        Assertions.assertEquals(Short.MAX_VALUE, Numbers.safeCastIntToShort(Short.MAX_VALUE));
        Assertions.assertEquals(Short.MIN_VALUE, Numbers.safeCastIntToShort(Short.MIN_VALUE));
    }

    @Test
    void castLongToByte() {
        Assertions.assertEquals(1, Numbers.safeCastLongToByte(1L));
        Assertions.assertEquals(10, Numbers.safeCastLongToByte(10L));
        Assertions.assertEquals(-1, Numbers.safeCastLongToByte(-1L));
        Assertions.assertEquals(Byte.MAX_VALUE, Numbers.safeCastLongToByte(Byte.MAX_VALUE));
        Assertions.assertEquals(Byte.MIN_VALUE, Numbers.safeCastLongToByte(Byte.MIN_VALUE));
    }

    @Test
    void castUnsignedShortToInt() {
        Assertions.assertEquals(1, Numbers.unsignedShortToInt((short) 1));
        Assertions.assertEquals(Short.MAX_VALUE, Numbers.unsignedShortToInt(Short.MAX_VALUE));
        Assertions.assertEquals((Short.MAX_VALUE << 1) | 1, Numbers.unsignedShortToInt((short) -1));
    }

    @Test
    void checkLongCeilingPowerOfTwo() {
        Assertions.assertEquals(1L, Numbers.ceilingPowerOfTwo(1L));
        Assertions.assertEquals(2L, Numbers.ceilingPowerOfTwo(2L));
        Assertions.assertEquals(8L, Numbers.ceilingPowerOfTwo(5L));
        Assertions.assertEquals(32L, Numbers.ceilingPowerOfTwo(32L));
        Assertions.assertEquals(1024L, Numbers.ceilingPowerOfTwo(1023L));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(Long.MAX_VALUE));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(0L));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(-1L));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(Long.MIN_VALUE));
    }

    @Test
    void checkIntCeilingPowerOfTwo() {
        Assertions.assertEquals(1, Numbers.ceilingPowerOfTwo(1));
        Assertions.assertEquals(2, Numbers.ceilingPowerOfTwo(2));
        Assertions.assertEquals(8, Numbers.ceilingPowerOfTwo(5));
        Assertions.assertEquals(32, Numbers.ceilingPowerOfTwo(32));
        Assertions.assertEquals(1024, Numbers.ceilingPowerOfTwo(1023));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(Integer.MAX_VALUE));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(0));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(-1));
        assertThrows(IllegalArgumentException.class, () -> Numbers.ceilingPowerOfTwo(Integer.MIN_VALUE));
    }

    @Test
    void checkPowerOfTwo() {
        Assertions.assertTrue(Numbers.isPowerOfTwo(1));
        Assertions.assertFalse(Numbers.isPowerOfTwo(5));
        Assertions.assertTrue(Numbers.isPowerOfTwo(8));
        Assertions.assertTrue(Numbers.isPowerOfTwo(1024));
        Assertions.assertFalse(Numbers.isPowerOfTwo(Long.MAX_VALUE));
        assertThrows(IllegalArgumentException.class, () -> Numbers.isPowerOfTwo(0));
        assertThrows(IllegalArgumentException.class, () -> Numbers.isPowerOfTwo(-1));
        assertThrows(IllegalArgumentException.class, () -> Numbers.isPowerOfTwo(Long.MIN_VALUE));
    }

    @Test
    void shouldFloorPowerOfTwo() {
        long value = 35;
        assertThat(Numbers.floorPowerOfTwo(value)).isEqualTo(32);
    }
}
