require 'socket'
require 'securerandom'
require 'active_model'

require 'rubypitaya/core/path'
require 'rubypitaya/core/config'
require 'rubypitaya/core/session'
require 'rubypitaya/core/postman'
require 'rubypitaya/core/parameters'
require 'rubypitaya/core/routes_base'
require 'rubypitaya/core/handler_router'
require 'rubypitaya/core/etcd_connector'
require 'rubypitaya/core/nats_connector'
require 'rubypitaya/core/database_config'
require 'rubypitaya/core/redis_connector'
require 'rubypitaya/core/instance_holder'
require 'rubypitaya/core/database_connector'
require 'rubypitaya/core/initializer_content'
require 'rubypitaya/core/initializer_broadcast'
require 'rubypitaya/core/application_files_importer'

module RubyPitaya

  class Main

    attr_reader :redis_connector, :config, :bll

    def initialize
      @environment_name = ENV.fetch("RUBYPITAYA_ENV") { 'development' }
      @is_development_environment = @environment_name == 'development'

      @application_files_importer = ApplicationFilesImporter.new
      @application_files_importer.import
      @application_files_importer.auto_reload if @is_development_environment

      @server_name = ENV['SERVER_NAME']
      @service_uuid = SecureRandom.uuid
      @desktop_name = Socket.gethostname

      @etcd_prefix = ENV['ETCD_PREFIX']
      @etcd_address = ENV['ETCD_URL']
      @etcd_lease_seconds = ENV['ETCD_LEASE_SECONDS'].to_i
      @allow_reconnect = false
      @etcd_connector = EtcdConnector.new(@service_uuid, @desktop_name,
                                          @server_name, @etcd_prefix,
                                          @etcd_address, @allow_reconnect,
                                          @etcd_lease_seconds)
      @etcd_connector.connect

      @nats_address = ENV['NATS_URL']
      @nats_connector = NatsConnector.new(@nats_address, @service_uuid,
                                          @server_name)

      @redis_address = ENV['REDIS_URL']
      @redis_connector = RedisConnector.new(@redis_address)
      @redis_connector.connect

      @database_config = DatabaseConfig.new(@environment_name, Path::DATABASE_CONFIG_PATH)
      @database_connector = DatabaseConnector.new(@database_config)
      @database_connector.connect

      @session = Session.new
      @postman = Postman.new(@nats_connector)
      @config = Config.new(Path::APP_CONFIG_FOLDER_PATH)
      @config.auto_reload if @is_development_environment

      @bll = InstanceHolder.new

      @initializer_content = InitializerContent.new(@bll, @redis_connector.redis)
      @initializer_broadcast = InitializerBroadcast.new
      @initializer_broadcast.run(@initializer_content)

      @handler_router = HandlerRouter.new(Path::HANDLERS_FOLDER_PATH,
                                          Path::ROUTES_FILE_PATH)

      run_server
    end

    private

    def run_server
      @is_shutting_down = false

      catch :sig_shutdown do
        Signal.trap("SIGINT") { throw :sig_shutdown }
        Signal.trap("SIGQUIT") { throw :sig_shutdown }
        Signal.trap("SIGTERM") { throw :sig_shutdown }

        puts "Server started!"
        run_nats_connection
      end

      Signal.trap("SIGINT", nil)
      Signal.trap("SIGQUIT", nil)
      Signal.trap("SIGTERM", nil)

      shutdown_server
    end

    def shutdown_server
      return if @is_shutting_down
      @is_shutting_down = true

      puts "Server shutting down..."

      @etcd_connector.disconnect
      @database_connector.disconnect

      exit(0)
    end

    def run_nats_connection
      @nats_connector.connect do |request|
        start_time_seconds = Time.now.to_i

        message_route = request[:msg][:route]
        message_data = request[:msg][:data]
        message_data = JSON.parse(message_data) if message_data.class == String

        params = Parameters.new(message_data)

        session_id = request[:session][:id]
        session_uid = request[:session].fetch(:uid, '')
        session_data = request[:session][:data]
        session_data = JSON.parse(session_data) if session_data.class == String
        frontend_id = request[:frontendID]
        metadata = request[:metadata]
        metadata = JSON.parse(metadata) if metadata.class == String

        @session.update(session_id, session_uid, session_data, metadata,
                        frontend_id)

        handler_name, action_name = message_route.split('.')[1..-1]

        puts "request  -> route: #{message_route}"
        puts "         -> data:  #{message_data}"

        response = @handler_router.call(handler_name, action_name, @session,
                                        @postman, @redis_connector.redis,
                                        @config, @bll, params)

        delta_time_seconds = Time.now.to_i - start_time_seconds

        puts "response [#{delta_time_seconds}s] -> #{response.to_json}"

        response
      end
      rescue Exception => error
        puts "ERROR: #{error}"
        puts error.backtrace
        run_nats_connection
    end
  end
end