General :: Script To Check Password Security

Im trying to make a script that will test the suitability of a password. I understand that all the features I want are in the /etc/pam.d/common-password file. From here I can change the length of a password, what characters must be in a password, if the words are in the dictionary, etc... but I don't know how to change these values by using a script. I want it in a script because I want to be able to suggest a more suitable password if the original password doesn't meet the criteria.