registrar-printer

Gemfile

# frozen_string_literal: true
source "https://rubygems.org"

gem "redis"
gem "pry"

Gemfile.lock

GEM
  remote: https://rubygems.org/
  specs:
    redis (3.3.3)

PLATFORMS
  ruby

DEPENDENCIES
  redis

BUNDLED WITH
   1.14.3

printer.rb

require 'redis'
require 'json'
require 'pry'

REDIS = Redis.new(url: ENV['REDIS_URL'])
REDIS_CHANNEL = ENV['REDIS_CHANNEL'] || 'ctf-registrar-development'

TTY = File.open("/dev/tty0", 'w')
TTY.sync = true
LP = File.open("/dev/usb/lp0", 'w')
LP.sync = true
LP.print "\x1b@" # reset

def enc(string)
  string.to_s.encode('cp437', fallback: proc do |c|
                       c.codepoints.map do |k|
                         "\x1dB1\\u#{k.to_s(16).rjust(4, '0')}\x1dB0"
                       end.join
                     end
                    )
end

def ps(string)
  TTY.puts string
  LP.puts enc(string)
end

def w(string)
  TTY.write string
  LP.write enc(string)
end

def justify(justification)
  LP.write "\x1ba#{justification}"
end

def header(content)
  LP.write "\x1b!\x28"
  justify 1
  TTY.write "\033[1;45m"
  LP.puts enc(content)
  TTY.write content
  TTY.write "\033[0m "
  justify 0
  LP.write "\x1b!\x00"
end

def ugc
  LP.write "\x1b!\x81"
  TTY.write "\033[1m"
  yield
  TTY.write "\033[0m"
  LP.write "\x1b!\x00"
end

def timestamp
  LP.puts
  LP.write "\x1b!\x01"
  TTY.write " \033[1;30m"
  justify 1
  w Time.now.utc
  justify 0
  TTY.write "\033[0m"
  LP.write "\x1b!\x00"
  ps ''
  LP.puts
end

def format(message_kind, subject, rest='')
  header do
    ps message_kind
  end

  ps subject

  unless rest.empty?
    ps rest
  end
end

def user_create(d)
  username = d['user']['username']

  header "User Signup"

  ugc do
    w username
  end
end

def team_create(d)
  username = d['user']['username']
  teamname = d['team']['name']

  header "Team Create"

  ugc do
    w username
  end
  w " created "
  ugc do
    w teamname
  end
end

def team_join(d)
  username = d['user']['username']
  teamname = d['team']['name']

  header "Team Join"

  ugc do
    w username
  end
  w " joined "
  ugc do
    w teamname
  end
end

REDIS.subscribe REDIS_CHANNEL do |on|
  on.subscribe do |channel, subscriptions|
    TTY.puts "subscribed to #{channel} with #{subscriptions} subscriptions"


    trap :INT do
      LP.write "\n\n\n\n\n\x1dV0"
      TTY.puts "EXITING #{Time.now.utc}"
      exit
    end

  end
  on.message do |_channel, msg|
    d = JSON.parse msg

    message_kind = d['kind']
    unless respond_to?(message_kind, d)
      TTY.puts "UNKNOWN MESSAGE #{message_kind}"
      next
    end

    send message_kind, d
    timestamp
  end
end