#!/usr/bin/env ruby
require "timeout"
include Timeout

RAILS_ROOT = File.dirname(__FILE__) + "/.."
LOG_ROOT = File.join(RAILS_ROOT, "log")
PID_PATTERN = File.join(LOG_ROOT, "futures*.pid")

max_time = (ARGV.first || "60").to_i
puts "Waiting up to #{max_time} seconds for future daemons to die"
begin
  timeout(max_time) do
    loop do
      files = Dir[PID_PATTERN]
      if files.empty? then
        puts "No log/futures*.pid files left -- safe to return"
        exit(0)
      end

      pids = []
      files.each do |file|
        pids << File.open(file, "rb") {|f| f.read.chomp}
      end

      cmd = "ps -p #{pids.join(",")} -o pid | tail -n -#{pids.size}"
      processes = `#{cmd}`.split
      unless $?.success? then
        puts "Could not get process status information on #{pids.join(" ")}"
        exit(1)
      end

      exit(0) if processes.empty?

      puts "#{Time.now.utc}: Waiting for process(es) #{pids.join(", ")} to die..."
      sleep 7
    end
  end
rescue Timeout::Error
  puts "!!! Daemons did not stop within #{max_time} seconds !!!"
  exit(1)
end