/*
 * Adapted from The MIT License (MIT)
 *
 * Copyright (c) 2018-2024 DaPorkchop_
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software
 * is furnished to do so, subject to the following conditions:
 *
 * Any persons and/or organizations using this software must include the above copyright notice and this permission notice,
 * provide sufficient credit to the original authors of the project (IE: DaPorkchop_), as well as provide a link to the original project.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *
 */

package net.daporkchop.lib.primitive.map.hash;

import lombok.experimental.UtilityClass;
import net.daporkchop.lib.common.math.BinMath;
import net.daporkchop.lib.common.math.PMath;

import static net.daporkchop.lib.common.util.PValidation.*;

/**
 * Various constants used by hash map implementations.
 *
 * @author DaPorkchop_
 */
@UtilityClass
public class HashMapHelper {
    public static final int DEFAULT_INITIAL_CAPACITY = 1 << 4;
    public static final int MAXIMUM_CAPACITY = 1 << 30;
    public static final float DEFAULT_LOAD_FACTOR = 0.75f;

    public static int tableSizeFor(int capacity) {
        return PMath.clamp(BinMath.unsignedBitCeil(notNegative(capacity, "capacity")), 1, MAXIMUM_CAPACITY);
    }

    public static int thresholdFor(int currentCapacity, float loadFactor) {
        return PMath.floorI(currentCapacity * loadFactor);
    }
}
