module Ecom
  module Core
    class CrewContract < ApplicationRecord
      include AASM

      belongs_to :crew
      belongs_to :crew_type
      has_many :crew_contract_transactions

      validates :status, :contract_no, :from, :to, :place_of_work, :probation_period,
                :contract_type, :wage, :wage_in_words, :crew_type_id, :crew_type, presence: true
      validates :contract_no, uniqueness: true
      validate :validate_date_range

      validates :wage, presence: true, numericality: { greater_than: 0 }

      validates_uniqueness_of :crew_id,
                              scope: :status,
                              if: :contract_in_effect_exists?,
                              message: 'There can only be one contract' \
                               ' with status `In effect` for a given crew at a time'

      def contract_in_effect_exists?
        contracts_in_effect = Ecom::Core::CrewContract.where(crew_id: crew_id, status: 'in_effect')

        return true unless contracts_in_effect.empty?

        false
      end

      def validate_date_range
        return unless from && to

        errors.add(:to, 'cannot be before from date.') if from >= to
      end

      aasm column: 'status' do
        state :draft, initial: true
        state :submitted_for_approval
        state :approved
        state :rejected
        state :in_effect
        state :void

        event :submit_for_approval do
          transitions from: :draft, to: :submitted_for_approval, guard: -> { status == 'draft' }
        end

        event :approve do
          transitions from: :submitted_for_approval, to: :approved, guard: -> { status == 'submitted_for_approval' }
        end

        event :reject do
          transitions from: :submitted_for_approval, to: :rejected, guard: -> { status == 'submitted_for_approval' }
        end

        event :commence do
          transitions from: :approved, to: :in_effect, guard: -> { status == 'approved' }
        end

        event :terminate do
          transitions from: :in_effect, to: :void, guard: -> { status == 'in_effect' }
        end
      end
    end
  end
end