fab-manager/app/models/coupon.rb

class Coupon < ActiveRecord::Base
  has_many :invoices

  after_commit :create_stripe_coupon, on: [:create]
  after_commit :delete_stripe_coupon, on: [:destroy]

  validates :name, presence: true
  validates :code, presence: true
  validates :code, format: { with: /\A[A-Z0-9]+\z/ ,message: 'only caps letters and numbers'}
  validates :code, uniqueness: true
  validates :percent_off, presence: true
  validates :percent_off, :inclusion => 0..100
  validates :validity_per_user, presence: true

  def safe_destroy
    if self.invoices.size == 0
      destroy
    else
      false
    end
  end

  def status
    if not active?
      'disabled'
    elsif (!valid_until.nil?) and valid_until.at_end_of_day < DateTime.now
      'expired'
    elsif (!max_usages.nil?) and invoices.count >= max_usages
      'sold_out'
    else
      'active'
    end
  end

  def create_stripe_coupon
    StripeWorker.perform_async(:create_stripe_coupon, id)
  end

  def delete_stripe_coupon
    StripeWorker.perform_async(:delete_stripe_coupon, code)
  end

end