Grzegorz,
As discussed, please add the additional code to generate the Google Analytics visitor flow function your previous programming.
Once complete, please provide instructions on which functions I need to merge with the existing code base.
Hi there. I have implemented Google analytics API using oAuth for my project & I have implemented the reports same as Google analytics provides including visitor data, traffic data, mobile data etc. I will complete this stuff you as soon as possible. Please let me know if you are interested. Thank you.