require 'singleton'

module Scrivito
  module Migrations
    class MigrationStore
      include Singleton

      def backend
        @backend ||= CmsBackend.new
      end

      def versions
        @versions ||= MultiJson.load(backend.read.presence || '[]')
      end

      def add_version(version)
        versions << version

        backend.save(MultiJson.dump(versions))
      end
    end
  end
end