#!/usr/bin/env ruby

$LOAD_PATH << File.join(File.dirname(__FILE__), *%w[.. lib])
load "scout_realtime.rb"  # bootstraps everything, including all other requires
require "dante"           # ... except dante, which is required here because it's only relevant to running via command line
require "fileutils"       # ... and fileutils, which we use for setting up the home directory

# exit if Ruby version 1.9 on Mac
if RUBY_VERSION =~ /^1\.9/ && ServerMetrics::SystemInfo.os.include?("darwin")
  puts "Scout realtime doesn't work with Ruby 1.9.x on Mac. If you are using RVM, try switching to Ruby 2.0 (preferred), or 1.8.7"
  exit
end

# by default, scout_realtime puts its pid and logfile in ~/.scout/
home_dir =  File.join( (File.expand_path("~") rescue "/"), ".scout" )
FileUtils.mkdir_p(home_dir) # ensure home directory exists
pid_path = File.join(home_dir, "scout_realtime.pid")
log_path = File.join(home_dir, "scout_realtime.log")

# parse the command
cmd = ARGV.first
command = nil
command = :start if cmd.nil? || cmd =~/^\-/
command = cmd.downcase.to_sym if cmd && %w(start stop help).include?(cmd.downcase)

# parse the options

opts = Trollop::options do
  banner <<-EOS
Stream realtime server metrics to your browser!

To start the daemon:
      scout_realtime start OR JUST scout_realtime
To stop it:
      scout_realtime stop

To view in your browser, do ONE of the following:

A) create an SSH tunnel: ssh -NL 5555:localhost:5555 user@ip_or_hostname (run that command on your own computer, not the server)
   then point your browser to: http://localhost:5555
   --- OR ---
B) open a port in your firewall: sudo iptables -A INPUT -p tcp --dport 5555 -j ACCEPT (run that command on your server)
   then point your browser to: http://your-ip-or-hostname:5555

* FYI, the log file is: #{log_path} by default
* See http://scoutapp.github.io/scout_realtime for more info


Advanced options:
  EOS

  opt :port, "point your web browser to this port to view realtime metrics.", :default => 5555, :short => "-p"
  opt :foreground, "run in the foreground, i.e., don't daemonize the process. Useful for debugging.", :default => false, :short => "-f"
  opt :log_path, "full path for a log file", :default=>log_path
  opt :pid_path, "full path for a PID file", :default=>pid_path
  #opt :quiet, "don't print anything to console on start or stop", :default=>false
end

# if these were left as defaults, they'll be unchanged from the initial assignment above
log_path = opts[:log_path]
pid_path = opts[:pid_path]

startup_message=<<EOS
* if you haven't already, open port #{opts[:port]} in your firewall. See http://scoutapp.github.io/scout_realtime for details
* Point your browser to http://your-ip-or-hostname:#{opts[:port]}
* FYI, the log file is: #{log_path}
EOS

# TODO: should be able to pass :daemonize => !opts[:foreground] to Dante::Runner instead
if opts[:foreground]
  puts " ** Initializing. cntl-c to stop. Logging to STDOUT **"
  Scout::Realtime::Main.instance(:port=>opts[:port]).go_sinatra
  puts startup_message
else
  if command == :start
    if Scout::Realtime.port_occupied?(opts[:port])
      puts "Local port #{opts[:port]} doesn't appear to be available - try another port."
      exit
    end

    Dante::Runner.new('scout_realtime').execute(:daemonize => !opts[:foreground], :pid_path => pid_path, :log_path => log_path, :port=>opts[:port]) do |options|
      Scout::Realtime::Main.instance(:port=>options[:port]).go_sinatra
    end
    puts startup_message
    puts  '* "scout_realtime stop" to stop the daemon'


    # Fork another process to run briefly & check that the primary daemon stayed running
    pid = IO.read(pid_path).chomp.to_i
    fork do
      sleep 2
      is_still_running = begin
        Process.getpgid( pid )
        true
      rescue Errno::ESRCH
        false
      end

      if !is_still_running
        puts "\n## oh-oh, the daemon crashed. See log at #{log_path} ##\n"
      end
    end

  elsif command == :stop
    Dante::Runner.new('scout_realtime').execute(:kill => true, :pid_path => pid_path)
  elsif command == :help
    puts "to get help: scout_realtime --help "
  end
end