Vacuum Apple Mail Envelope Index

vacuum_apple_mail_envelope_index.scpt

(*
Speed up Mail.app by vacuuming the Envelope Index
Code from: http://www.hawkwings.net/2007/03/03/scripts-to-automate-the-mailapp-envelope-speed-trick/
Originally by "pmbuko" with modifications by Romulo
Updated by Brett Terpstra 2012
Updated by Mathias Törnblom 2015 to support V3 in El Capitan and still keep backwards compability
*)

tell application "Mail" to quit
set os_version to do shell script "sw_vers -productVersion"
set mail_version to "V2"
considering numeric strings
	if "10.10" < os_version then set mail_version to "V3"
	if "10.11" < os_version then set mail_version to "V4"
	if "10.12" < os_version then set mail_version to "V5"
	if "10.13" < os_version then set mail_version to "V6"
end considering

set sizeBefore to do shell script "ls -sk ~/Library/Mail/" & mail_version & "/MailData | grep -E 'Envelope Index$' | awk {'print $1 / 1024'}"
do shell script "/usr/bin/sqlite3 ~/Library/Mail/" & mail_version & "/MailData/Envelope\\ Index vacuum"

set sizeAfter to do shell script "ls -sk ~/Library/Mail/" & mail_version & "/MailData | grep -E 'Envelope Index$' | awk {'print $1 / 1024'}"

display dialog ("Mail index before: " & (round (sizeBefore * 100)) / 100 & " MB" & return & "Mail index after: " & (round (sizeAfter * 100)) / 100 & " MB" & return & return & "Enjoy the new speed!")

tell application "Mail" to activate