#!/usr/bin/env ruby

require 'eventmachine'
require 'optparse'
require 'securerandom'

$LOAD_PATH << File.expand_path('../../lib', File.dirname(__FILE__))

require 'remailer'

# == Support Methods ========================================================

class Exerciser
  attr_reader :report

  def initialize(options)
    @options = options
    @pending = [ ]
    @report = { }
  end

  def test(server)
    results = @report[server] = {
      success: 0,
      timeout: 0,
      error: 0
    }

    @options[:count].times do
      uuid = SecureRandom.uuid

      @pending << uuid

      connection_options = {
        close: true,
        proxy: {
          host: @options[:proxy_host],
          port: @options[:proxy_port]
        },
        connect: lambda do |success, host|
          results[success ? :success : :error] += 1
          @pending.delete(uuid)
        end
      }

      if (@options[:verbose])
        connection_options[:debug] = STDOUT
      end

      Remailer::SMTP::Client.open(server, connection_options)
    end
  end

  def done?
    @pending.empty?
  end
end

# == Main ===================================================================

options = {
  count: 1,
  concurrency: 1,
  proxy_host: 'localhost',
  proxy_port: 1080
}

opts = OptionParser.new do |parser|
  parser.banner = "Usage: exerciser [options] server [server [...]]"
  parser.on('-n', '--count=n') do |n|
    options[:count] = n.to_i
  end
  parser.on('-c', '--concurrency=n') do |n|
    options[:concurrency] = n.to_i
  end
  parser.on('-X', '--proxy=s') do |s|
    server, port = s.split(/:/)

    options[:proxy_host] = server

    if (port)
      options[:proxy_port] = port.to_i
    end
  end
  parser.on('-v', '--verbose') do
    options[:verbose] = true
  end
end

servers = opts.parse(*ARGV)

unless (servers.any?)
  puts opts
  exit(0)
end

EventMachine.run do
  exerciser = Exerciser.new(options)

  servers.each do |server|
    exerciser.test(server)
  end

  EventMachine.add_periodic_timer(0.1) do
    if (exerciser.done?)
      puts '%-40s %-6s %-6s' % [ 'Server', 'Success', 'Fail' ]
      puts '-' * 58
      exerciser.report.each do |server, results|
        puts '%-40s %6d %6d' % [ server, results[:success], results[:error] ]
      end

      EventMachine.stop_event_loop
    end
  end
end