Bill.rb

class Bill < ActiveRecord::Base
  attr_accessible :invoice, :amount, :initiated_by_id, :payer_id, :origin_id, :destination_id ,:accepted, :paid, :auto, :frequency, :payments_left

  belongs_to :initiated_by, class_name: 'Member', foreign_key: :initiated_by_id
  belongs_to :payer, class_name: 'Member', foreign_key: :payer_id
  belongs_to :origin, class_name: 'Account', foreign_key: 'origin_id'
  belongs_to :destination, class_name: 'Account', foreign_key: 'destination_id'

  validates_numericality_of :amount, greater_than_or_equal_to: 0.01
  validates :amount, :presence => {message: "cannot be blank"}

  scope :recent, order('created_at DESC')

  before_save :valid_destination?
  before_save :valid_funds?, on :update
  before_save :pay, on :update
  before_save :auto_bill, on :update

  def pay
    if accepted == true
      balance_accounts
    end
  end

  def auto_bill
    if auto == true && accepted == true && payments_left > 0
      self.class.create(attributes.update(payments_left: payments_left - 1))
    end
  end

  def balance_accounts
    destination_new_balance = destination.balance + amount
    destination.update_attributes(:balance => destination_new_balance)
    origin_new_balance = origin.balance - amount
    origin.update_attributes(:balance => origin_new_balance)
  end

  def valid_funds?
    return true if amount <= origin.balance
    errors[:base] << "Sorry, you do not have enough funds"
    return false
  end

  def valid_destination?
    #different test needed for users of account
    return true if initiated_by.id != destination.owner_id
    errors[:base] << "Sorry, you can not send funds to the same account"
    return false
  end

end