RubyDNS Shout Game

#!/usr/bin/env ruby

require 'rubydns'
require 'rubydns/extensions/string'

INTERFACES = [
	[:udp, '0.0.0.0', 5300],
	[:tcp, '0.0.0.0', 5300]
]

Name = Resolv::DNS::Name
IN = Resolv::DNS::Resource::IN

# Use upstream DNS for name resolution.
UPSTREAM = RubyDNS::Resolver.new([[:udp, '8.8.8.8', 53], [:tcp, '8.8.8.8', 53]])

class PlayerState
	def initialize(name)
		@name = name
		
		@x = @y = 0
		
		@shouts = ["Hello"]
	end
	
	attr :name
	
	attr_accessor :x
	attr_accessor :y
	
	attr :shouts
	
	def inspect
		"<PlayerState #{@name}>"
	end
end

class GameState
	KEYS = {
		'w' => [0, 1],
		's' => [0, -1],
		'a' => [-1, 0],
		'd' => [1, 0]
	}
	
	def initialize
		@players = {}
		@width = @height = 5
		@map = @height.times.collect{[[]] * @width}
	end
	
	attr :players
	
	def register(name)
		player = @players[name] = PlayerState.new(name)
		@map[player.x][player.y] << player
	end
	
	def move(username, input)
		player = @players[username]
		
		@map[player.x][player.y].delete(player)
		
		input.each_char do |c|
			direction = KEYS[c]
			
			player.x = (player.x + direction[0]) % @width
			player.y = (player.y + direction[1]) % @height
		end
		
		@map[player.x][player.y] << player
		
		return "Moved #{player.x}, #{player.y}"
	end
	
	def shout(username, input)
		player = @players[username]
		
		puts @map.inspect
		
		@map[player.x][player.y].each do |other_player|
			puts "Shouted #{input.inspect} at #{other_player.name}"
			
			other_player.shouts << input
		end
		
		return "Shouted #{input}"
	end
end

# Start the RubyDNS server
RubyDNS.run_server(listen: INTERFACES) do
	@logger.level = Logger::INFO
	
	game_state = GameState.new
	
	match(/([a-z]{3,8})\.register/, IN::TXT) do |transaction, match|
		username = match[1]
		
		puts game_state.players.inspect
		
		if game_state.players.include? username
			transaction.fail! :Refused
		else
			game_state.register(username)
			transaction.respond!("Registered #{username}")
		end
	end
	
	match(/([wsad]+)\.([a-z]{3,8})\.move/, IN::TXT) do |transaction, match|
		input = match[1]
		username = match[2]
		
		puts "Input: #{input} Username: #{username}"
		puts "Players: #{game_state.players.keys.inspect}"
		
		if game_state.players.include? username
			status = game_state.move(username, input)
			
			transaction.respond!(status)
		else
			transaction.fail! :Refused
		end
	end
	
	match(/([a-z]{3,8})\.shouts/, IN::TXT) do |transaction, match|
		username = match[1]
		
		if game_state.players.include? username
			shouts = game_state.players[username].shouts
			
			transaction.respond!(*shouts)
		else
			transaction.fail! :Refused
		end
	end
	
	match(/([a-z]{2,20})\.([a-z]{3,8})\.shout/, IN::TXT) do |transaction, match|
		input = match[1]
		username = match[2]
		
		puts "Shout: #{input} Username: #{username}"
		
		if game_state.players.include? username
			status = game_state.shout(username, input)
			
			transaction.respond!(status)
		else
			transaction.fail! :Refused
		end
	end
end