Cronjob to send customer a daily report via email

My customer requested to have a daiiy report via email.
The only exception is if you work over night. Then the (last) entry will not be included.
Setup the cron like this:
55 23 * * * /path/to/php /absolute/path/to/kimai/shellscripts/cron.php
this will run 23:55 every day.
For the cronjob to work, there must be an email address set in the customer settings. Also the system administrator email address should be set. This will be the sender address.