RaspberryPi low level script

Situation: I have 2 oil tanks were i want to log the oil level from, when its on low level there must be an email send so i get alerted to fill up the tank. This project: - should work on Raspberry Pi version 1, 2 and 3 - scripts must containt full comments -for each oil tank i have 1 low level switch that is connected to the Pi, for each low level switch is an green and red LED for indication. When a low level switch is down a LED red burns and a email must be send with text " oil level is low " the mailscript must work like this, I must emulate an browser so it can send email from behind a firewall. (because all ports are blocked except port 80) Only 1 email message can be send every 12 hours and the message must be logged into a database. Time when level was low and after when level was normal again, so we can make a history of the oil levels.