Add Logging to HR Application

I would like to add some logging to OrangeHRM. There is logging functionality already available in the application. I would like to extend it to record: (1) when users log in and out of the system (2) When they press "Save" in the Time Sheet module. Similar to: eg: "20150101" "09:20" "154" "Log In" "-" "20150101" "09:34" "154" "Saved Time Sheet" "39" "20150101" "09:36" "154" "Log Out" "-" "date" "time" "employeeid" "action" "related id (eg timesheet unique id)" Only OrangeHRM experts to apply with Symfony, php and mysql skills Thanks