def pid_file_exists?(pid_file)
  test(*("[ -f #{pid_file} ]").split(' '))
end

def process_exists?(pid_file)
  pid_file_exists?(pid_file) and test(*("kill -0 $( cat #{pid_file} )").split(' '))
end

namespace :load do
  task :defaults do
    set :crono_pid, -> { File.join(shared_path, 'tmp', 'pids', 'crono.pid') }
    set :crono_env, -> { fetch(:rack_env, fetch(:rails_env, fetch(:stage))) }
    set :crono_log, -> { File.join(shared_path, 'log', 'crono.log') }
    set :crono_role, -> { :app }
  end
end

namespace :crono do
  desc "Start crono"
  task :start do
    on roles fetch(:crono_role) do
      pid_file = fetch(:crono_pid)
      args = []
      args.push "--daemonize"
      args.push "--pidfile #{pid_file}"
      args.push "--logfile #{fetch(:crono_log)}"
      args.push "--environment #{fetch(:crono_env)}"
      within release_path do
        execute(:bundle, :exec, :crono, args.compact.join(' ')) unless process_exists?(pid_file)
      end
    end
  end

  desc "Stop crono"
  task :stop do
    on roles fetch(:crono_role) do
      if test("[ -d #{release_path} ]")
        pid_file = fetch(:crono_pid)
        execute("kill -TERM `cat #{pid_file}`") if process_exists?(pid_file)
      end
    end
  end

  desc 'Restart crono'
  task :restart do
    invoke 'crono:stop'
    invoke 'crono:start'
  end
end

after 'deploy:updated', 'crono:stop'
after 'deploy:reverted', 'crono:stop'
after 'deploy:published', 'crono:start'