Canada has mandatory minimum's:
A. Offences Involving Firearms and Other Weapons
"One year (first conviction) and three years (second or subsequent conviction) for using a firearm in the commission of an indictable offence, in an attempt, or during flight afterwards (1977)"
If they want to be hardasses and make an example out of him, they can easily say that the marijuana was packaged (separate bags) to be sold, i'm not sure of the canadian laws on how many MDMA pills it takes to be considered intent to deliver, but i'm sure BOTH are indictable charges if they want to take it to that level.
Like everyone has said, don't go at it alone, get a lawyer even for the pre-trial. You can always get a public defender to represent you and file for your motion of discovery, which is where the prosecution will give you all the evidence they have on you. Then take that to a "Real" lawyer and go from there.
If you're a first time offender, any good lawyer can plead it down.