Bash: I want to count letters and substitute text

OK so I'm extremely new to bash shell scripting and I've been pretty successful up until this point. I'm using BASH to fix a problem...

I want to tu a basic domain name: Buddies.forlife.com into |07|Buddies|07|forlife|03|com

Basically, I need it to count the letters and convert it to hex. To be clear, Not convert the domain name to hex, but the letter count to hex. I'm having a hard time replacing the period "."

I hope you understand what I'm trying to achieve...

Thanks for the help in advance!