index.ts

/**
 * Roll any number. When passing no arguments it returns a number between 0 - 100; including 0 and 100
 * @param {number} [minOrMax] When passing only 1 argument it returns a number between 0 and the argument; including 0 and the argument
 * @param {number} [max] When passing 2 arguments, they are considered "min" and "max"; it returns a number between min - max; including min and max
 * @returns {number}
 */
export function roll(minOrMax?: number, max?: number): number {
  let _min = 0
  let _max = 100
  if (minOrMax === void 0) {
    // keep 0 - 100
  } else if (max === void 0) {
    _min = 0
    _max = minOrMax
  } else {
    _min = minOrMax
    _max = max
  }
  return Math.floor(Math.random() * (_max - _min + 1)) + _min
}

/**
 * Returns 'heads' or 'tails' at random
 * @returns {'heads' | 'tails'}
 */
export function flip(): 'heads' | 'tails' {
  return roll(1) === 0 ? 'heads' : 'tails'
}

/**
 * Create a dice with any number of sides, dice(6).roll() to roll it!
 * You can also try rolling a specific side to return a boolean like so: dice(6).rollAssert(6).
 *
 * @export
 * @param {?number} [sides=6] The number of sides
 * @returns {{ sides: number, roll: () => number, rollAssert: (target: number) => boolean }}
 */
export function Dice(sides = 6): {
  sides: number
  roll: () => number
  rollAssert: (target: number) => boolean
} {
  return {
    sides,
    roll(): number {
      return roll(1, this.sides)
    },
    rollAssert(targetNumber: number): boolean {
      return roll(1, this.sides) === targetNumber
    },
  }
}