require 'protobuf/rpc/connectors/base'

module Protobuf
  module Rpc
    module Connectors
      class Zmq < Base
        include Protobuf::Rpc::Connectors::Common
        include Protobuf::Logger::LogMethods

        def send_request
          timeout_wrap do
            setup_connection
            connect_to_rpc_server
            post_init
            read_response
          end
        ensure
          @socket.close if @socket
          @zmq_context.terminate if @zmq_context
          @zmq_context = nil
        end

        def log_signature
          @_log_signature ||= "[client-#{self.class}]"
        end

        private

        def close_connection
          return if @error
          zmq_error_check(@socket.close)
          zmq_error_check(@zmq_context.terminate)
          log_debug { sign_message("Connector closed")  }
        end

        def connect_to_rpc_server
          return if @error
          log_debug { sign_message("Establishing connection: #{options[:host]}:#{options[:port]}") }
          @zmq_context = ::ZMQ::Context.new
          @socket = @zmq_context.socket(::ZMQ::REQ)
          zmq_error_check(@socket.connect("tcp://#{options[:host]}:#{options[:port]}"))
          log_debug { sign_message("Connection established #{options[:host]}:#{options[:port]}") }
        end

        # Method to determine error state, must be used with Connector api
        def error?
          !!@error
        end

        def read_response
          return if @error
          @response_data = ''
          zmq_error_check(@socket.recv_string(@response_data))
          parse_response
        end

        def send_data
          return if @error
          log_debug { sign_message("Sending Request: #{@request_data}") }
          @stats.request_size = @request_data.size
          zmq_error_check(@socket.send_string(@request_data))
          log_debug { sign_message("write closed") }
        end

        def zmq_error_check(return_code)
          raise "Last API call failed at #{caller(1)}" unless return_code >= 0
        end
      end
    end
  end
end