Ruby IRC

irc.rb

require "socket"

class IRC

	def initialize(info)
		@server = info[:server]
		@port = info[:port] || 6667
		@password = info[:password]
		@nick = info[:nick]
		@channel = info[:channel]
		@real = info[:real] || "Ruby IRC Bot"
		@debug = info[:debug] || false
		@callbacks = {
			"connect" => [],
			"join" => [],
			"part" => [],
			"nick" => [],
			"message" => [],
			"pm" => [],
			"quit" => []
		}
		on("connect") { send "JOIN #{@channel}" }
	end

	def send(command)
		puts "---> #{command}" if @debug
		@irc.send "#{command}\n", 0
	end

	def handle_server_input(s)
		case s.strip
			when /^PING :(.+)$/i
				puts "[ Server ping ]" if @debug
				send "PONG :#{$1}"
			when /^:(.+?)!(.+?)@(.+?)\sPRIVMSG\s.+\s:[\001]PING (.+)[\001]$/i
				puts "[ CTCP PING from #{$1}!#{$2}@#{$3} ]" if @debug
				send "NOTICE #{$1} :\001PING #{$4}\001"
			when /^:(.+?)!(.+?)@(.+?)\sPRIVMSG\s.+\s:[\001]VERSION[\001]$/i
				puts "[ CTCP VERSION from #{$1}!#{$2}@#{$3} ]" if @debug
				send "NOTICE #{$1} :\001VERSION Ruby-irc v0.042\001"
			when /:(.+?)\sMODE\s(.+?)\s:\+iwx/i
				# connect
				@callbacks["connect"].each { |callback| callback.call() }
			when /^:(.+?)!(.+?)@(.+?)\sPRIVMSG\s(.+)\s:(.+)$/i
				# message
				# $1 = user; $4 = room; $5 = message
				if($4 == @nick)
					@callbacks["pm"].each { |callback| callback.call($1, $5) }
				else
					@callbacks["message"].each { |callback| callback.call($4, $1, $5) }
				end
			when /^:(.+?)!(.+?)@(.+?)\sJOIN\s:(.+?)$/i
				# join
				# $1 = user; $4 = room
				@callbacks["join"].each { |callback| callback.call($4, $1) }
			when /^:(.+?)!(.+?)@(.+?)\sPART\s(.+?)$/i
				# part
				# $1 = user; $4 = room
				@callbacks["part"].each { |callback| callback.call($4, $1) }
			when /^:(.+?)!(.+?)@(.+?)\sQUIT\s:Quit:\s(.+?)$/i
				# quit
				@callbacks["quit"].each { |callback| callback.call($1) }
			when /^:(.+?)!(.+?)@(.+?)\sNICK\s:(.+?)$/i
				# change nick
				# $1 = nick; $4 = new_nick
				@callbacks["nick"].each { |callback| callback.call($1, $4) }
			else
				puts s if @debug
		end
	end

	def main
		while true
			ready = select([@irc, $stdin], nil, nil, nil)
			next if !ready
			for s in ready[0]
				if s == $stdin
					# allow user to send command via STDIN in debug
					if @debug
						return if $stdin.eof
						s = $stdin.gets
						send s
					end
				elsif s == @irc
					return if @irc.eof
					s = @irc.gets
					handle_server_input(s)
				end
			end
		end
	end

	def connect
		@irc = TCPSocket.open(@server, @port)
		send "PASS #{@password}" if @password
		send "USER #{@real} hostname servername :#{@real}"
		send "NICK #{@nick}"
		begin
			main
		rescue Interrupt
		rescue Exception => e
			puts e.message
			print e.backtrace.join("\n")
			retry
		end
	end

	def on(listener, &block)
		@callbacks[listener].push(block)
	end

	def join(channel)
		send "JOIN #{channel}"
	end

	def say(who, msg)
		send "PRIVMSG #{who} #{msg}"
	end

end

usage.rb

irc = IRC.new({
	:server => "irc.server.com",
	:port => 6667, # optional
	:password => "foobar", # optional
	:nick => "Rubot",
	:real => "Rubot", #optional
	:debug => true # optional
})

### listeners

irc.on("connect") do
	# called when you have registered on the server
end

irc.on("join") do |channel, nick|
	# called when a user joins a channel
end

irc.on("part") do |channel, nick|
	# called when a user leaves a channel
end

irc.on("nick") do |nick, new_nick|
	# called when a user changes their nick
end

irc.on("message") do |channel, nick, message|
	# called when a user sends a message to a channel
end

irc.on("pm") do |nick, message|
	# called when a user sends a private message to you
end

irc.on("quit") do |nick|
	# called when a user quits
end

### methods

irc.connect # connect to the server

irc.join("channel") # join a channel

irc.say("channel/nick", "message") # leave a message to a channel or user