How Do I Beat A Charge I Never Commited?

What is the name of your state? Florida

on may 4th 2007 a little after 2am i was standing on the corner looking for my friend but he was knowhere in sight so as i was about to leave to go to his house then go home my other friend that i know walked up and saw me smoking a cigarette and he asked to smoke some so i let him have it. me knowing he smokes crack cocaine he asked if i had some hard i said "no". so we both walked off the same direction but he stopped at somones house and i was walking to my friends house while smoking another cigarette and listening to my mp3 player. as i stopped to change the music and started walking off i was roughly grabbed by the arm forcing my to lose my cigarette and had a taser pushed in my stomache and was asked what do i have. then remembering i had four (4) bags of marijuana on me. one bag was really didnt have any mrijuana in it. then i was taken in a corner of a building and he reached in my pockets and grabbed the four bags of marijuana and he said "is this all you got?" and i replied "yes'sir" and he put handcuffs on me and put me in the police car. and about 5 minutes later the person who asked me to smoke my cigarette was arrested while walking through the same path i was. i was never read my rights. then we were takin to avon park police department where i was charged with:
1. possesion of drug paraphanalia
2. possesion of cannabis under 20 grams
3. purchase of cannabis
im guilty of the first two charges but not the last charge because i was given the marajuana since the day before. but in the affidavit they say they saw what seemed to be a hand-to-hand transaction and that it was clearly visible from the ambiant lighting of the moon. that night the moon was out a little but it was not giving off a bright light. and he stated he was 50 feet away. and that he saw the guy that i let have a cigarette (but in the affidavit he was described as a "subject"). but the police stated he seem a hand-tohand transaction and i exchanged an undisclosed amount of currency an exchange for four (4) zip lock bags full of plant-like material. but the "subject" who was arrested with me never had any currency on him nor marijuana. so how does this case sound to you? i never been arrested for a drug charge cause i dont sell drugs. yes i smoke marijuana but dont sell.
so what do you think will happen?