99 Bottles of Beer

module.exports = class BeerWall {
  static sing(starting = 99, ending = 0) {
    this.validate(starting, ending);

    return [...this.recite(starting, ending)].join('\n\n');
  }

  static *recite(starting, ending) {
    const wall = new BeerWall(starting);

    while ((yield* wall) > ending) {}
  }

  static verse(bottles) {
    return new BeerWall(bottles).verse();
  }

  static validate() {
    if (typeof arguments[0] !== 'number' || typeof arguments[1] !== 'number') {
      throw new TypeError('Invalid type: starting and ending must be numbers');
    }

    if (arguments[0] > 99 || arguments[0] < 0) {
      throw new RangeError('Invalid starting');
    }

    if (arguments[1] > 99 || arguments[1] < 0) {
      throw new RangeError('Invalid ending');
    }

    if (arguments[0] < arguments[1]) {
      throw new RangeError('starting must be greater or equal to ending');
    }
  }

  constructor(bottles) {
    this.bottles = bottles;
  }

  *[Symbol.iterator]() {
    const current = this.bottles;

    yield this.verse();

    return current;
  }

  verse() {
    return (
      `${this.Quantity} ${this.container} of beer on the wall, ` +
      `${this.quantity} ${this.container} of beer.\n` +
      `${this.action()}, ` +
      `${this.quantity} ${this.container} of beer on the wall.`
    );
  }

  get Quantity() {
    const quantity = this.quantity;

    return quantity.charAt(0).toUpperCase() + quantity.substr(1);
  }

  get quantity() {
    switch (this.bottles) {
    case 0:
      return 'no more';
    default:
      return this.bottles.toString();
    }
  }

  get container() {
    switch (this.bottles) {
    case 1:
      return 'bottle';
    default:
      return 'bottles';
    }
  }

  get pronoun() {
    switch (this.bottles) {
    case 1:
      return 'it';
    default:
      return 'one';
    }
  }

  action() {
    const pronoun = this.pronoun;
    const bottles = this.bottles--;

    if (bottles === 0) {
      this.bottles = 99;
    }

    switch (bottles) {
    case 0:
      return 'Go to the store and buy some more';
    default:
      return `Take ${pronoun} down and pass it around`;
    }
  }
};