module PipeRpc
  class Hub::Servers
    def initialize
      @servers = Hash.new{ |hash, key| raise NoServerError.new("no server #{key.inspect}") }
    end

    def add(server)
      id, server = if server.respond_to? :to_rpc_server_id
        [server.to_rpc_server_id, server]
      else
        server.first
      end

      raise ServerRegistrationError.new("server id #{id.inspect} no symbol") unless id.is_a? Symbol

      if registered? id
        raise ServerRegistrationError.new("server id #{id.inspect} already used for another server")
      else
        @servers[id] = server
      end
    end

    def registered?(id)
      @servers.has_key?(id)
    end

    def registered_ids
      @servers.keys
    end

    def [](id)
      @servers[id]
    end

    def remove(id)
      @servers.delete(id)
    end
  end
end