if defined?(ActiveRecord)
  class ActiveRecord::Base
    # serialize to YAML
    def encode_with(coder)
      coder["attributes"] = @attributes
      coder.tag = ['!ruby/ActiveRecord', self.class.name].join(':')
    end
  end
end

class Delayed::PerformableMethod
  # serialize to YAML
  def encode_with(coder)
    coder.map = {
      "object" => object,
      "method_name" => method_name,
      "args" => args
    }
  end
end

module Psych
  module Visitors
    class YAMLTree
      def visit_Class(klass)
        tag = ['!ruby/class', klass.name].join(':')
        register(klass, @emitter.start_mapping(nil, tag, false, Nodes::Mapping::BLOCK))
        @emitter.end_mapping
      end
    end

    class ToRuby
      def visit_Psych_Nodes_Mapping_with_class(object)
        return revive(Psych.load_tags[object.tag], object) if Psych.load_tags[object.tag]

        case object.tag
        when /^!ruby\/class:?(.*)?$/
          resolve_class $1
        when /^!ruby\/ActiveRecord:(.+)$/
          klass = resolve_class($1)
          payload = Hash[*object.children.map { |c| accept c }]
          id = payload["attributes"][klass.primary_key]
          begin
            if ActiveRecord::VERSION::MAJOR == 3
              klass.unscoped.find(id)
            else # Rails 2
              klass.with_exclusive_scope { klass.find(id) }
            end
          rescue ActiveRecord::RecordNotFound
            raise Delayed::DeserializationError
          end
        when /^!ruby\/Mongoid:(.+)$/
          klass = resolve_class($1)
          payload = Hash[*object.children.map { |c| accept c }]
          begin
            klass.find(payload["attributes"]["_id"])
          rescue Mongoid::Errors::DocumentNotFound
            raise Delayed::DeserializationError
          end
        else
          visit_Psych_Nodes_Mapping_without_class(object)
        end
      end
      alias_method_chain :visit_Psych_Nodes_Mapping, :class

      def resolve_class_with_constantize(klass_name)
        klass_name.constantize
      rescue
        resolve_class_without_constantize(klass_name)
      end
      alias_method_chain :resolve_class, :constantize
    end
  end
end