class IAPManager
  attr_reader :in_app_purchase_id

  def initialize(in_app_purchase_id)
    @in_app_purchase_id = in_app_purchase_id
  end

  def purchase
    @purchaser = PM::IAP::Product.new(in_app_purchase_id)

    @purchaser.purchase do |status, transaction|
      case status
      when :in_progress then show_spinner
      when :deferred    then hide_spinner
      when :purchased   then complete_transaction
      when :canceled    then go_away
      when :error       then error(transaction.error.localizedDescription)
      end
    end
  end

  def show_spinner
    CCHUD.showWithStatus('Purchasing course')
  end

  def hide_spinner
    CCHUD.dismiss
  end

  def complete_transaction
    CCHUD.showSuccessWithStatus('Course purchased')
  end

  def error(message)
    CCHUD.showErrorWithStatus(message)
  end

  def go_away
    CCHUD.dismiss
  end
end