growitter.rb

require 'rubygems'
require 'twitter'
require 'ruby-growl'
require 'simple-daemon'
require 'tempfile'
require 'net/http'

class Growitter < SimpleDaemon::Base
  SimpleDaemon::WORKING_DIRECTORY = "/Users/dir/Desktop"

  @@twit = Twitter::Base.new('username', 'password')
  @@options = {}
  @@profile_image_cache = {}

  def self.start
    puts "Starting growitter"

    loop do
      timeline = @@twit.timeline(:friends, @@options)
      if timeline
        timeline.reverse.each do |s|
          unless @@profile_image_cache.has_key?(s.user.profile_image_url)
            f = Tempfile.new("growitter")
            f << Net::HTTP.get(URI.parse(s.user.profile_image_url))
            f.close
            @@profile_image_cache[s.user.profile_image_url] = f.path
          end

          system "growlnotify -n growitter --image #{@@profile_image_cache[s.user.profile_image_url]} -t #{s.user.name.inspect} -m #{s.text.inspect}"

          @@options[:since_id] = s.id
        end
      end
      sleep 60
    end
  end

  def self.stop
    puts "Stopping growitter"
  end
end

Growitter.daemonize