8 Days to take a Piss-test, please help

Hey guys, got a job through a temp-agency a while ago and now I’m going through the steps of becoming a permanent employee. Had no clue there’d be a drug test, but I gotta go to a specific urgent care place and piss in a cup within the next 8 days.

Typically I get home from work and smoke like, half a bong pack most evenings. On weekends it could be a full bowl or two that I smoke in a day.

My game plan is of course to stop smoking, drink a ton of water every day, all that jazz. Considering my daily usage, do you think water and green tea and that kind of stuff will be enough, or should I try to get my hands on one of those intense detox drinks? The optimist in me says I should be good, but I’m naturally a bit worried. Any and all advice is welcome.