Arduino Beta - Fixing the download URL + Adding a caveat

Casks/arduino-beta.rb

@@ -1,10 +1,29 @@
 cask :v1 => 'arduino-beta' do
   version '1.5.8'
-  sha256 'f5678cf9146031af52519d79dfcb16a81aa9c7eb68e516b34c679139048fb000'
 
-  url "http://downloads.arduino.cc/arduino-#{version}-macosx-java7-r2.zip"
+  if MacOS.version < :lion
+    depends_on :java => '6'
+
+    sha256 'c69f870f99ccaf2abb3618845559daea9ef8c52a68ff42b5e21ae3a69cf845fa'
+    url "http://arduino.cc/download.php?f=/arduino-#{version}-macosx.zip"
+  else
+    depends_on :java => '7'
+
+    sha256 'f5678cf9146031af52519d79dfcb16a81aa9c7eb68e516b34c679139048fb000'
+    url "http://arduino.cc/download.php?f=/arduino-#{version}-macosx-java7.zip"
+
+    caveats <<-EOS.undent
+      Version #{version} for Java 7+ is experimental (see http://arduino.cc/en/Main/Software).
+      If you experience problems running it please download the Java 6 version
+
+        http://arduino.cc/download.php?f=/arduino-#{version}-macosx.zip
+
+      and install it manually.
+    EOS
+  end
+
   homepage 'http://arduino.cc/'
-  license :unknown
+  license :oss
 
   app 'Arduino.app'
 end