module JamRuby
  class MusicNotation < ActiveRecord::Base
    include JamRuby::S3ManagerMixin

    self.primary_key = 'id'

    attr_accessible :file_url, :size, :file_name

    belongs_to :user, :class_name => "JamRuby::User", foreign_key: :user_id
    belongs_to :music_session, :class_name => "JamRuby::MusicSession", foreign_key: :music_session_id

    mount_uploader :file_url, MusicNotationUploader

    before_destroy :delete_s3_files

    validates :file_url, :presence =>  true
    validates :size, :presence => true

    before_validation do
      if file_url.present? && file_url_changed?
        self.size = file_url.file.size
      end
    end

    def s3_url
      s3_manager.s3_url(self[:file_url])
    end

    def sign_url(expiration_time = 120)
      s3_manager.sign_url(self[:file_url], {:expires => expiration_time, :secure => false})
    end

    private

    def delete_s3_files
      s3_manager.delete(self[:file_url]) if self[:file_url]
    end
  end
end