How to print last login time?

Question

I'd like to know how to set in .bashrc file to print the last login time of users when logging into another user in terminal. I do know that with who or last, but I'd like something a little more customizable that can be formatted and only runs once per login, preferably to show in a format like so;

last login time [ 2015-02-13 @ 3:50:00 AM ]
user@host /path/dir/here $

that gets printed to the terminal screen before the bash prompt, and if possible to set and format color on the time and date stamp. How can I achieve this to customizing the bash prompt output?

Solution

(Just as a guideline, the format is not exactly the same):

ll=$(last -1 -R  $USER | head -1 | cut -c 20-)
export PS1="last login time [$ll]"'\n\h:\W\$ '

Edit: if you want last information to be printed only once (wise idea)

ll=$(last -1 -R  $USER | head -1 | cut -c 20-)
echo "last login time [$ll]"    # adjust to your login messages, fortunes, etc
export PS1='\n\h:\W\$ '         # replace by your favorite prompt

Comments

[Jeff Schaller]

I'd recommend the user's personal ~/.bashrc file over the system-wide one, in case other users are not interested in such output. Otherwise, this seems to use the code from JJoao's answer and so should be credited there.

[Richard A. Allcorn - rAllcorn]

I'm not so interested in who gets the credit but in helping out. Thanks for pointing that out though.