clamp.ts

// Copyright (c) 2020 Jozty. All rights reserved. MIT license.

import curryN from './utils/curry_n.ts';
import type { PH } from './utils/types.ts';

// @types
type Clamp_1<T> = (min: T) => T;

type Clamp_2<T> = (max: T) => T;

type Clamp_3<T> = (value: T) => T;

type Clamp_2_3<T> =
  & ((max: T) => Clamp_3<T>)
  & ((max: PH, value: T) => Clamp_2<T>)
  & ((max: T, value: T) => T);

type Clamp_1_3<T> =
  & ((min: T) => Clamp_3<T>)
  & ((min: PH, value: T) => Clamp_1<T>)
  & ((min: T, value: T) => T);

type Clamp_1_2<T> =
  & ((min: T) => Clamp_2<T>)
  & ((min: PH, max: T) => Clamp_1<T>)
  & ((min: T, max: T) => T);

type Clamp =
  & (<T>(min: T) => Clamp_2_3<T>)
  & (<T>(min: PH, max: T) => Clamp_1_3<T>)
  & (<T>(min: PH, max: PH, value: T) => Clamp_1_2<T>)
  & (<T>(min: T, max: T) => Clamp_3<T>)
  & (<T>(min: T, max: PH, value: T) => Clamp_2<T>)
  & (<T>(min: PH, max: T, value: T) => Clamp_1<T>)
  & (<T>(min: T, max: T, value: T) => T);

function _clamp<T extends number | string>(
  min: T,
  max: T,
  value: T,
): T {
  if (min > max) {
    throw new Error(
      'Minimum value must be smaller than Maximum value',
    );
  }
  return value < min ? min : value > max ? max : value;
}

/**
 * Restricts `value` between `min` and `max`.
 * Returns `min` if `value < min`, `max` if `value > max`, `value` otherwise
 *
 *      Fae.clamp(1, 10, -5) // => 1
 *      Fae.clamp(1, 10, 15) // => 10
 *      Fae.clamp(1, 10, 4)  // => 4
 */
export const clamp = curryN(3, _clamp) as Clamp;