require 'sinatra/base'
require 'sinatra-websocket'
require 'thin'

module Junkie
  module Webinterface

    # Class that represents the web interface for junkie. It is based on
    # WebSockets, so that updates are sent to the connected clients.
    #
    class Interface < Sinatra::Base
      include Log, Config

      DEFAULT_CONFIG = {
        port: 8080,
      }

      set :server, 'thin'

      def self.setup(channels)
        @@channels = channels
        @@config = Config.get_config(self)

        set :port, @@config[:port]

        @@stats = Hash.new

        @@encrypted_episodes = Hash.new

        # every connected client connects to the following channel, so infos
        # pushed to this channel are transmitted to the clients
        @@ws_channel = EM::Channel.new

        # subscribe to the channel that holds the stats from various parts of
        # junkie
        @@channels[:info].subscribe do |info|
          @@stats[info[:key]] = info
          @@ws_channel.push(info)
        end

        # get new encrypted episode links
        @@channels[:episodes].subscribe do |episode|
          next unless episode.status == :encrypted

          @@encrypted_episodes[episode.uuid] = episode
          publish_encrypted_count
        end

        run!
      end

      def self.publish_encrypted_count
        @@channels[:push_episode_count].push(@@encrypted_episodes.length)

        @@channels[:info].push(
            {
                key: "Pending Encrypted Links",
                desc: "Number of encrypted links that need to be decrypted.",
                value: @@encrypted_episodes.length,
                additional: @@encrypted_episodes.values.map { |e| "%s (%s)" % [e.series, e.id] }
            }
        )
      end

      get '/' do
        if !request.websocket?
          @junkie_version = Junkie::VERSION
          @server = request.host_with_port
          erb :index
        else

          request.websocket do |ws|
            ws.onopen do
              log.debug("Opened WebSocket from #{ request.ip }")

              # send all cached stats to the client
              @@stats.values.each { |s| ws.send(s.to_json) }

              @@ws_channel.subscribe do |info|
                ws.send(info.to_json)
              end
            end

            ws.onclose do
              log.debug("Closed WebSocket from #{ request.ip }")
              # TODO unsubscribe from @@ws_channel
            end
          end
        end
      end

      get '/links/encrypted' do
        content_type :json
        @@encrypted_episodes.values.map {|e| e.to_hash }.to_json
      end

      post '/links/decrypt/:uuid' do
        uuid = params["uuid"]
        decrypted_links = JSON.parse(request.body.read).fetch("links") { [] }

        if @@encrypted_episodes.has_key?(uuid) and !decrypted_links.empty?
          episode = @@encrypted_episodes.delete(uuid)
          episode.status = :decrypted
          episode.links = decrypted_links

          @@channels[:episodes].push(episode)
          Interface.publish_encrypted_count

          status 201
          decrypted_links.to_json
        else
          status 404
        end
      end

      post "/app/:service" do
        registration_id = JSON.parse(request.body.read).fetch('regid') { nil }

        if params['service'] != 'gcm' or registration_id == nil
          status 404
        else
          @@channels[:push_registration].push([:gcm, registration_id])
          status 201
        end
      end
    end
  end
end