class Todo < ActiveRecord::Base
  ASSIGNED     = 1
  MENTIONED    = 2
  BUILD_FAILED = 3

  belongs_to :author, class_name: "User"
  belongs_to :note
  belongs_to :project
  belongs_to :target, polymorphic: true, touch: true
  belongs_to :user

  delegate :name, :email, to: :author, prefix: true, allow_nil: true

  validates :action, :project, :target_type, :user, presence: true
  validates :target_id, presence: true, unless: :for_commit?
  validates :commit_id, presence: true, if: :for_commit?

  default_scope { reorder(id: :desc) }

  scope :pending, -> { with_state(:pending) }
  scope :done, -> { with_state(:done) }

  state_machine :state, initial: :pending do
    event :done do
      transition [:pending] => :done
    end

    state :pending
    state :done
  end

  def build_failed?
    action == BUILD_FAILED
  end

  def body
    if note.present?
      note.note
    else
      target.title
    end
  end

  def for_commit?
    target_type == "Commit"
  end

  # override to return commits, which are not active record
  def target
    if for_commit?
      project.commit(commit_id) rescue nil
    else
      super
    end
  end

  def target_reference
    if for_commit?
      target.short_id
    else
      target.to_reference
    end
  end
end