#
#
# = Jeeves Scheduler
#
# == Schedule Jeeves related tasks from recordings to shutdowns and wakeups
#
# Author:: Robert Sharp
# Copyright:: Copyright (c) 2011 Robert Sharp
# License:: Open Software Licence v3.0
#
# This software is licensed for use under the Open Software Licence v. 3.0
# The terms of this licence can be found at http://www.opensource.org/licenses/osl-3.0.php
# and in the file copyright.txt. Under the terms of this licence, all derivative works
# must themselves be licensed under the Open Software Licence v. 3.0
#
# This scheduler will schedule at jobs and use wolly to schedule wakeups. It is a Jerbil
# service.
#

require 'jerbil/jerbil_service/base'
require 'jerbil/jerbil_service/support'
require 'jerbil/support'

require 'jeeves/config'
require 'jeeves/errors'

require 'open3'

#
# == Jeeves Service
#
# Synopsis of the whole service
#
module Jscheduler

  # add generic class methods
  extend JerbilService::Support
  
  # inherit the Jeeves config file
  class Config < Jeeves::Config; end  

  # === Jeeves Service class
  #
  # Description of how the service class works
  #
  class Service < JerbilService::Base

    # Document the constructor as required.
    #
    # pkey:: string - private key that must be used for
    #        supervision calls (e.g. stop_callback)
    # options:: hash of options, preferably as created by Jeckyl. See documentation
    #           on JerbilService::Base for assumed options re logging etc
    #
    def initialize(pkey, options)
      
      @tuner = options[:tuner]
      raise InvalidTuner("Tuner is not recognized: #{@tuner}") unless Schedulers.has_key?(@tuner)

      # do things that cannot be done when $SAFE > 0

      # the symbol should be the app name and must correspond to a service in /etc/services
      super(:jschedule, pkey, options)

      # DRb is now working, this process may have daemonized and $SAFE = 1
      
      @logger.verbose("Started scheduler for tuner #{@tuner}")

    end

    #
    # define additional class methods to make things happen
    #
    
    def schedule(params={})
      [:filename, :channel, :start, :duration].each do |param|
        raise Jeeves::MissingParam, "Schedule method must specify #{param}" unless params.has_key?(param)
      end
      mode = params[:mode] || :avi
      raise InvalidMode, "Tuner #{@tuner} does not have mode: #{mode}" unless Schedulers[@tuner].has_key?(mode)
      scheduler = Schedulers[@tuner][mode]
      
      startParam = params[:start].strftime("%H:%M %b %d")
		
			command = "#{scheduler} #{params[:channel]} #{params[:duration]} #{params[:filename]}"
      
      @logger.debug "About to schedule: #{command}"
			
      # need open3 to get the full communication with at
			inpipe, outpipe, errpipe = Open3.popen3("/usr/bin/at #{startParam}")
			inpipe.puts command
			inpipe.close
			response = errpipe.readlines
      outpipe.close
      errpipe.close

      # get the job id and return it to the caller
      jobnum = nil
      job_re = /job (\d+) at/
      response.each do |resp|
        @logger.debug "Response includes: " + resp
        if results = job_re.match(resp) then
          @logger.debug "Recognised Job: " + results[1]
          jobnum = results[1].clone
        end
      end
      
      @logger.info "Scheduled recording on #{params[:channel]} at #{startParam} for #{params[:duration]} with job no: #{jobnum}"
      # set a wol timer here
      
			return jobnum
		rescue Jeeves::JeevesError
      raise
    rescue
      @logger.exception($!)
      return '0'
		end

    
    # deletes the at job with the given job number
    # assume that the given jobnum is valid
    def delete_schedule(jobnum)
      begin
        @logger.info "Removing job: #{jobnum}"
        system("/usr/bin/atrm #{jobnum.to_s}")
      rescue
        @logger.exception($!)
      end
    end

    # do not redefine the superclass methods unless you are absolutely sure you know
    # what you are doing.
    
    protected
    
    Schedulers = {
      :dvb=>{
        :avi=>'/usr/local/bin/virea-dvb-record.sh', 
        :ts=>'/usr/local/bin/virea-dvb-record-ts.sh'
      },
      :pvr=>{
        :avi=>'/usr/local/bin/virea-pvr-record.sh',
        :ts=>'/usr/local/bin/virea-pvr-record-ts.sh'
      }
    }

  end
end