require 'eventmachine'

module Adminix
  class Watcher
    attr_reader :quit

    def self.run!(app_service, options)
      Adminix.logger.info "Starting watcher PID is #{Process.pid}"
      EM.run do
        w = Adminix.watcher = Adminix::Watcher.new(app_service, options)
        c = Adminix.config
        p = c.watcher_period

        if c.web_debugger_enabled?
          Adminix.logger.info "Web debugger is running on port #{c.server_port}"
          EM.start_server('0.0.0.0', c.server_port, Web::Router)
        end
        if Adminix.config.watch_system_load?
          EM.add_periodic_timer(p[:check_system_load]) { w.perform(:check_system_load) }
          EM.add_periodic_timer(p[:send_system_load]) { w.perform(:send_system_load) }
        end
        if Adminix.config.watch_logs?
          EM.add_periodic_timer(p[:send_logs]) { w.perform(:send_logs) }
          Adminix.config.log_files.each do |path|
            EventMachine.file_tail(path, Adminix::Helpers::LogReader)
          end
        end
        if c.credentials_defined?
          EM.add_periodic_timer(p[:sync_service]) { w.perform(:sync_service) }
        end
        EM.add_periodic_timer(p[:execute_jobs]) { w.perform(:execute_jobs) }
        EM.add_periodic_timer(2) do
          if w.quit && !w.wait?
            Adminix.logger.info 'Stopping watcher...'
            EM.stop
          end
        end

        trap('TERM') { w.stop }
        trap('INT') { w.stop }
      end
    end

    def initialize(app_service, options)
      @options = options
      @running_jobs = []
      @app_service = app_service
      @system_load_service = Services::SystemLoadService.new(service)
      @quit = false
    end

    def perform(job)
      return if @running_jobs.include?(job) || @quit

      @running_jobs << job
      send(job)
      @running_jobs.delete(job)
    end

    def check_logs
      Adminix.logger.debug 'Checking logs...'
    end

    def check_system_load
      Adminix.logger.debug 'Checking system load...'
      @system_load_service.create_stamp
    end

    def sync_service
      Adminix.logger.info 'Syncing service...'
      @app_service.sync
    end

    def execute_jobs
      return unless @app_service.service.new_jobs?
      Adminix.logger.info 'Executing jobs...'
      @app_service.run_jobs
    end

    def send_logs
      Adminix.logger.debug 'Adding logs to sending queue...'
      @app_service.allow_sending_logs
    end

    def send_system_load
      Adminix.logger.debug 'Adding system load to sending queue...'
      @app_service.allow_sending_system_load
    end

    def wait?
      !@running_jobs.count.zero?
    end

    def service
      @app_service.service
    end

    def app_service
      @app_service
    end

    def stop
      @quit = true
    end
  end
end