// Functional approach //
const functionalTrue = (onTrue, onFalse) => onTrue;
const functionalFalse = (onTrue, onFalse) => onFalse;
const isDivisible = (dividend, divisor) => [functionalTrue, ...Array(divisor).fill(functionalFalse)][dividend % divisor];

const functionalFizzBuzz = (n) => {
  const divisible_by_three = isDivisible(n, 3);
  const divisible_by_five = isDivisible(n, 5);
  return divisible_by_three(divisible_by_five("FizzBuzz", "Fizz"), divisible_by_five("Buzz", n));
};

// Object-oriented approach //
const baseBoolean = {
  setThen: function(then) { return { ...this, then }; },
  setOtherwise: function(otherwise) { return { ...this, otherwise }; },
};
const objectOrientedTrue = {
  ...baseBoolean,
  evaluate: function() { return this.then; },
};
const objectOrientedFalse = {
  ...baseBoolean,
  evaluate: function() { return this.otherwise; },
};

const objectOrientedNumber = {
  value: 0,
  isaMultipleCache: [objectOrientedFalse],
  setValue: function(n) { return { ...this, value: n, isaMultipleCache: [objectOrientedTrue, ...Array(n).fill(objectOrientedFalse)] }; },
  isaMultipleOf: function(dividend) { return this.isaMultipleCache[dividend.value % this.value]; }
};

const objectOrientedFizzBuzz = {
  for: function(n) {
    const number = objectOrientedNumber.setValue(n);
    return this.three
               .isaMultipleOf(number)
               .setThen(
                 this.five
                     .isaMultipleOf(number)
                     .setThen("FizzBuzz")
                     .setOtherwise("Fizz")
                     .evaluate()
               )
               .setOtherwise(
                 this.five
                     .isaMultipleOf(number)
                     .setThen("Buzz")
                     .setOtherwise(number.value)
                     .evaluate()
               )
               .evaluate();
  },
  three: objectOrientedNumber.setValue(3),
  five: objectOrientedNumber.setValue(5),
};

// Output //

const input = Array.from(Array(30), (_,i) => i+1);

const functionalOutput = document.getElementById("functional");
const objectOrientedOutput = document.getElementById("object-oriented");

functionalOutput.innerText = input.map(functionalFizzBuzz);
objectOrientedOutput.innerText = input.map((n) => objectOrientedFizzBuzz.for(n));