apod

#!/usr/bin/ruby

require 'net/http'
require 'tempfile'
require 'uri'

feed_url = "http://www.nasa.gov/rss/dyn/lg_image_of_the_day.rss"
feed = Net::HTTP.get(URI.parse(feed_url))
image_filename = feed.split('url="http://www.nasa.gov/sites/default/files/')[1].split('"')[0]
image_url = "http://www.nasa.gov/sites/default/files/#{image_filename}"
image = Net::HTTP.get(URI.parse(image_url))

temp_file = Tempfile.new("apod")

begin
  temp_file.write(image)

  script = <<-SCRIPT
    tell application "Finder"
      set apod to POSIX file "#{temp_file.path}" as string
      set desktop picture to file apod
    end tell
  SCRIPT

  output = `osascript -e '#{script}'`
  process = $?
ensure
  temp_file.close
end

unless process.success?
  puts output
  exit 1
end