require "socrates/adapters/stubs"

module Socrates
  module Adapters
    class Memory
      include StubUserDirectory

      CLIENT_ID = "MEMORY"
      CHANNEL   = "C1"

      attr_reader :history
      attr_accessor :client_id

      def initialize
        super()
        @history = Hash.new { |hash, key| hash[key] = [] }
      end

      def client_id_from(context: nil, user: nil)
        raise ArgumentError, "Must provide one of :context or :user" if context.nil? && user.nil?

        @client_id || CLIENT_ID
      end

      def channel_from(context: nil, user: nil)
        raise ArgumentError, "Must provide one of :context or :user" if context.nil? && user.nil?

        user.nil? ? CHANNEL : users_channel(user)
      end

      def send_message(session, message, send_now: false)
        raise ArgumentError, "Channel is required" unless session.channel.present?

        session.messages[session.channel] << message
        flush_session(session, channel: session.channel) if send_now
      end

      def send_direct_message(session, message, recipient)
        raise ArgumentError, "Recipient is required" unless recipient.present?

        im_channel = users_channel(recipient)

        session.messages[im_channel] << message
      end

      def flush_session(session, channel: nil) # TODO: Dry this up? Session? Included module?
        session.messages.select { |c, _| channel.nil? || channel == c }.each do |c, messages|
          _send_message(c, messages.join("\n\n"))
          messages.clear
        end
      end

      #
      # Methods for fetching messages and dms in specs...
      #

      def msgs
        @history[CHANNEL]
      end

      def last_msg
        msgs[-1]
      end

      def dms(user)
        @history[users_channel(user)]
      end

      def last_dm(user)
        dms(user)[-1]
      end

      private

      def _send_message(channel, message) # TODO: Underscored name?
        @history[channel] << message
      end

      def users_channel(user)
        user.respond_to?(:id) ? user.id : user
      end
    end
  end
end