require 'active_record'
require 'rflow/configuration/uuid_keyed'

class RFlow
  class Configuration
    class Connection < ConfigDB
      class ConnectionInvalid < StandardError; end

      include UUIDKeyed
      include ActiveModel::Validations

      serialize :options, Hash

      belongs_to :input_port, :primary_key => 'uuid', :foreign_key => 'input_port_uuid'
      belongs_to :output_port,:primary_key => 'uuid', :foreign_key => 'output_port_uuid'

      before_create :merge_default_options!

      validates_uniqueness_of :uuid
      validates_presence_of :output_port_uuid, :input_port_uuid

      validate :all_required_options_present


      def all_required_options_present
        self.class.required_options.each do |option_name|
          unless self.options.include? option_name.to_s
            errors.add(:options, "must include #{option_name} for #{self.class.to_s}")
          end
        end
      end


      def merge_default_options!
        self.options ||= {}
        self.class.default_options.each do |option_name, default_value_or_proc|
          self.options[option_name.to_s] ||= default_value_or_proc.is_a?(Proc) ? default_value_or_proc.call(self) : default_value_or_proc
        end
      end


      # Should return a list of require option names which will be
      # used in validations.  To be overridden.
      def self.required_options; []; end


      # Should return a hash of default options, where the keys are
      # the option names and the values are either default option
      # values or Procs that take a single connection argument.  This
      # allow defaults to use other parameters in the connection to
      # construct the appropriate default value.
      def self.default_options; {}; end

    end


    # STI Subclass for ZMQ connections and their required options
    class ZMQConnection < Connection

      def self.default_options
        {
          'output_socket_type'    => 'PUSH',
          'output_address'       => lambda{|conn| "ipc://rflow.#{conn.uuid}"},
          'output_responsibility' => 'connect',
          'input_socket_type'     => 'PULL',
          'input_address'        => lambda{|conn| "ipc://rflow.#{conn.uuid}"},
          'input_responsibility'  => 'bind',
        }
      end
    end


    # STI Subclass for AMQP connections and their required options
    class AMQPConnection < Connection

      def self.default_options
        {
          'host'     => 'localhost',
          'port'     => 5672,
          'insist'   => true,
          'vhost'    => '/',
          'username' => 'guest',
          'password' => 'guest',

          # If a queue is created, these are the default parameters
          # for said queue type
          'queue_passive'     => false,
          'queue_durable'     => true,
          'queue_exclusive'   => false,
          'queue_auto_delete' => false,
          'queue_nowait'      => true,
        }
      end

    end
  end
end