require "pretty_print"
require "json"
require "openssl/hmac"


puts "Content-type: text/plain; charset=UTF-8"
puts

settings = Hash(String, String).new
["eventsub_secret", "channel"].each do |key|
  begin
    settings[key] = File.read( "/etc/twitch/" + key ).chomp
  rescue
    STDERR.puts "Warning: Missing /etc/twitch/" + key
  end
end

def ircmsg( channel : String, msg : String)
  if msg !~ /(\r|\n)/
    sock = Socket.unix
    sock.connect Socket::UNIXAddress.new( "/etc/twitch/irc-socket".to_s )
    sock.puts( "#" + channel + " " + "eventsub: " + msg )
    sock.close
  end
end

def effectsmsg( msg : String )
  sock = Socket.unix
  sock.connect Socket::UNIXAddress.new( "/etc/twitch/effects-socket" )
  sock.puts( msg )
  sock.close
rescue ex
  STDERR.puts( ex )
end

struct Nil
  def as_s?
    self
  end
  def as_i?
    self
  end
end

File.open("/tmp/eventsub.#{Process.pid}.txt", "w", 0o644 ) do |file|

  input = STDIN.gets_to_end

  begin
    json = JSON.parse( input )

    digest = "sha256=" + OpenSSL::HMAC.hexdigest( :sha256, settings["eventsub_secret"],  ENV["HTTP_TWITCH_EVENTSUB_MESSAGE_ID"] + ENV["HTTP_TWITCH_EVENTSUB_MESSAGE_TIMESTAMP"] + input )
    if json["challenge"]? && ( ENV["HTTP_TWITCH_EVENTSUB_MESSAGE_SIGNATURE"] == digest )
      STDOUT.puts( json["challenge"] )
      file.puts( json["challenge"] )
    elsif json["event"]?

      case json["subscription"]["type"]
      when "channel.update"
        #ircmsg( settings["channel"], "#{json["event"]["broadcaster_user_login"]} is now playing #{json["event"]["category_name"]} with the title #{json["event"]["title"]}" )
        effectsmsg( "overlay gltext #{json["event"]["broadcaster_user_login"]} is now playing #{json["event"]["category_name"]} with the title #{json["event"]["title"]}" )
      when "stream.online"
        ircmsg( settings["channel"], "| #{json["event"]["broadcaster_user_login"]} is now streaming!" )
      when "stream.offline"
        ircmsg( settings["channel"], "| #{json["event"]["broadcaster_user_login"]} is now offline." )
      when "channel.follow"
        ircmsg( settings["channel"], "#{json["event"]["user_login"]} is now following!" )
      when "channel.ban"
        ircmsg( settings["channel"], "#{json["event"]["user_login"]} is now banned!" )
      when "channel.unban"
        ircmsg( settings["channel"], "#{json["event"]["user_login"]} is now unbanned!" )
      when "channel.raid"
        effectsmsg( "overlay gltext #{json["event"]["from_broadcaster_user_login"]} is raiding with #{json["event"]["viewers"]} viewer(s)!" )
        ircmsg( settings["channel"], "#{json["event"]["from_broadcaster_user_login"]} is raiding with #{json["event"]["viewers"]} viewer(s)! bungmoBlobDance bungmoBlobDance bungmoBlobDance bungmoBlobDance" )
      when "channel.subscribe"
        sub_recver = ( json["event"]["user_login"]?.as_s?              || "anonymous" )
        sub_broadcaster = ( json["event"]["broadcaster_user_login"]?.as_s?    || "unknown" )
        sub_plan   = ( json["event"]["tier"]?.as_s?               || "unknown" )
        #sub_months = ( json["event"]["cumulative_months"]?.as_i? || 0 )
        effectsmsg( "overlay gltext 10 " + sub_recver + " subscribed!" )
        ircmsg( settings["channel"], sub_recver.to_s + " has subscribed at sub level #" + sub_plan.to_s + " bungmoBlobDance bungmoBlobDance bungmoBlobDance bungmoBlobDance" )
      when "channel.subscription.gift"
        sub_sender = ( json["event"]["user_login"]?.as_s?              || "anonymous" )
        sub_recver = ( json["event"]["broadcaster_user_login"]?.as_s?    || sub_sender )
        sub_plan   = ( json["event"]["tier"]?.as_s?               || "unknown" )
        sub_total  = ( json["event"]["total"]?.as_s? || "0" )
        sub_cumulative  = ( json["event"]["cumulative_total"]?.as_i? || 0 )
        effectsmsg( "overlay gltext 10 " + sub_sender + " donated " + sub_total +  " subs!" )
        ircmsg( settings["channel"], "#{sub_sender} has gifted #{sub_total} tier #{sub_plan} subscription for a total of #{sub_cumulative}" )
       when "channel.subscription.message"
        sub_sender = ( json["event"]["user_login"]?.as_s?              || "anonymous" )
        sub_plan   = ( json["event"]["tier"]?.as_s?               || "unknown" )
        sub_months = ( json["event"]["cumulative_months"]?.as_i? || 0 )
        sub_msg    = ( json["event"]["message"]["text"]?.as_s? || "" )
        effectsmsg( "overlay gltext 10 " + sub_sender + " subscribed!" )
        ircmsg( settings["channel"], sub_sender.to_s + " has subscribed for " + sub_months.to_s + " months at sub level #" + sub_plan.to_s + ": " + sub_msg.to_s )
      end
    else
      STDOUT.puts( json.pretty_inspect )
      STDOUT.puts( ARGV.pretty_inspect )
      STDOUT.puts( ENV.pretty_inspect )
      STDOUT.puts( file.path )
    end
    file.puts( json.pretty_inspect )
    file.puts( ARGV.pretty_inspect )
    file.puts( ENV.pretty_inspect )
  rescue ex
    STDERR.puts( ex )
    STDOUT.puts( input )
    file.puts( input )
  end

end


#{"subscription" =>
#  {"id" => "3c1c3a9c-748e-4374-8e61-2c0210755af3",
#   "status" => "enabled",
#   "type" => "channel.subscribe",
#   "version" => "1",
#   "condition" => {"broadcaster_user_id" => "59895482"},
#   "transport" =>
#    {"method" => "webhook",
#     "callback" => "https://twitch.fairlystable.org/eventsub"},
#   "created_at" => "2021-02-09T19:13:49.618252874Z",
#   "cost" => 0},
# "event" =>
#  {"user_id" => "71506453",
#   "user_login" => "shift_f7",
#   "user_name" => "Shift_F7",
#   "broadcaster_user_id" => "59895482",
#   "broadcaster_user_login" => "bungmonkey",
#   "broadcaster_user_name" => "BungMonkey",
#   "tier" => "1000",
#   "is_gift" => true}}
#