module Adhearsion
  module Asterisk
    class QueueProxy
      class QueueAgentsListProxy
        include Enumerable

        attr_reader :proxy, :agents

        def initialize(proxy, cached = false)
          @proxy  = proxy
          @cached = cached
        end

        def count
          if cached? && @cached_count
            @cached_count
          else
            @cached_count = proxy.environment.get_variable("QUEUE_MEMBER_COUNT(#{proxy.name})").to_i
          end
        end
        alias size count
        alias length count

        # @param [Hash] args
        # :name value will be viewable in the queue_log
        # :penalty is the penalty assigned to this agent for answering calls on this queue
        def new(*args)
          options   = args.last.kind_of?(Hash) ? args.pop : {}
          interface = args.shift

          raise ArgumentError, "You must specify an interface to add." if interface.nil?
          raise ArgumentError, "You may only supply an interface and a Hash argument!" if args.any?

          penalty             = options.delete(:penalty)            || ''
          name                = options.delete(:name)               || ''
          state_interface     = options.delete(:state_interface)    || ''

          raise ArgumentError, "Unrecognized argument(s): #{options.inspect}" if options.any?

          proxy.environment.execute "AddQueueMember", proxy.name, interface, penalty, '', name, state_interface

          added = case proxy.environment.get_variable("AQMSTATUS")
                  when "ADDED"         then true
                  when "MEMBERALREADY" then false
                  when "NOSUCHQUEUE"   then raise QueueDoesNotExistError.new(proxy.name)
                  else
                    raise "UNRECOGNIZED AQMSTATUS VALUE!"
                  end

          if added
            check_agent_cache!
            AgentProxy.new(interface, proxy).tap do |agent_proxy|
              @agents << agent_proxy
            end
          else
            false
          end
        end

        # Logs a pre-defined agent into this queue and waits for calls. Pass in :silent => true to stop
        # the message which says "Agent logged in".
        def login!(*args)
          options = args.last.kind_of?(Hash) ? args.pop : {}

          silent = options.delete(:silent).equal?(false) ? '' : 's'
          id     = args.shift
          id   &&= AgentProxy.id_from_agent_channel(id)
          raise ArgumentError, "Unrecognized Hash options to #login: #{options.inspect}" if options.any?
          raise ArgumentError, "Unrecognized argument to #login: #{args.inspect}" if args.any?

          proxy.environment.execute 'AgentLogin', id, silent
        end

        # Removes the current channel from this queue
        def logout!
          # TODO: DRY this up. Repeated in the AgentProxy...
          proxy.environment.execute 'RemoveQueueMember', proxy.name
          case proxy.environment.get_variable("RQMSTATUS")
          when "REMOVED"     then true
          when "NOTINQUEUE"  then false
          when "NOSUCHQUEUE"
            raise QueueDoesNotExistError.new(proxy.name)
          else
            raise "Unrecognized RQMSTATUS variable!"
          end
        end

        def each(&block)
          check_agent_cache!
          agents.each &block
        end

        def first
          check_agent_cache!
          agents.first
        end

        def last
          check_agent_cache!
          agents.last
        end

        def cached?
          @cached
        end

        def to_a
          check_agent_cache!
          @agents
        end

        private

        def check_agent_cache!
          if cached?
            load_agents! unless agents
          else
            load_agents!
          end
        end

        def load_agents!
          raw_data = proxy.environment.get_variable "QUEUE_MEMBER_LIST(#{proxy.name})"
          @agents = raw_data.split(',').map(&:strip).reject(&:empty?).map do |agent|
            AgentProxy.new agent, proxy
          end
          @cached_count = @agents.size
        end
      end
    end
  end
end