#!/usr/bin/env ruby
require '../lib/pxnx_jruby/spoon/pxnx_runner'
require 'timeout'

def setup()
    @pid_dir = File.join(File.dirname(__FILE__), '.')
    @name = "pxnx_daemon_process"
    @pid_path = File.join(@pid_dir, "#{@name}.pid")
    @pid = get_pid_from_file()
    @timeout = 120
end

def create_pid_file(pid)
    begin
        open(@pid_path, 'w') do |f|
        f.puts pid
    end
    rescue => e
        STDERR.puts "Error: Unable to open #{@pid_path} for writing:\n\t <#{e.message}>"
        exit
    end
end

def get_pid_from_file
    @pid = nil
    open(@pid_path, 'r') do |f|
        @pid = f.readline.to_s.gsub(/[^0-9]/,'')
    end
    rescue Errno::ENOENT => e
        #File does not exist. Leave PID at nil.
    @pid.to_i unless @pid.nil?
end

def remove_pid_file
    File.unlink(@pid_path)
    rescue => e
        STDERR.puts "ERROR: Unable to unlink #{@pid_path}:\n\t <#{e.message}>"
        exit
end

def running?
    setup()
    return false if @pid.nil?
    begin
        Process.kill(0, @pid.to_i)
        return true
    rescue Errno::ESRCH, TypeError  => e
        #STDERR.puts "Error querying PID <#{@pid}>! Error was <#{e.message}>";
        return false
    rescue Errno::EPERM
      STDERR.puts "No permission to query #{@pid}!";
      return false
    rescue => e
        STDERR.puts "ERROR: Unable to check PXNX status:\n\t <#{e.message}>"
        return false
    end
end

def stop
    setup()
    abort "PXNX is not running!" unless running?
    begin
        STDOUT.puts "Stopping process #{@pid}..."
        Timeout.timeout(@timeout) do
          Process.kill("TERM", @pid.to_i)
          sleep 5 while running?
        end
    rescue Timeout::Error
        STDERR.puts "Shutdown timeout... forcing shutdown!"
        Process.kill("KILL", @pid.to_i)
        sleep 5 while process_exists?
      end

	remove_pid_file
	STDOUT.puts "Process stopped."
end

def start()
    abort "Process already running!" if running?
      if pid = Spoon.spawnp('jruby', *ARGV)
        create_pid_file(pid)
        STDOUT.puts "Process started with pid #{pid}"
      else
        Process.setsid
      end
end

case ARGV.shift
    when 'start'
        start()
    when 'stop'
        stop()
    when 'restart'
        stop()
        start()
    when 'status'
        if running?
            STDOUT.puts "PXNX is running with pid #{@pid}"
        else
            STDOUT.puts "PXNX is not running."
        end
    else
        STDERR.puts "Usage: jruby pxnx_daemon.rb <start|stop|restart>"
        exit!
end