Was Alonzo playing Hoyt from the second they met?

Alonzo told Jake he'd been planning "all week" for killing Roger (then taking the money to pay off the Russians).

So I personally think he handpicked Jake as the shooter long before the movie began

Fuqua's DVD commentary (one of my favorites) spells it out as well; he actually sees Jake as a potential protégé, someone who can take over Alonzo's own street-job so that Alonzo himself can advance in rank towards becoming one of the "wise men." The other team members are corrupt, but not as ambitious or smart as Jake. Unfortunately, Jake wasn't corrupt enough to take over, and had to be killed instead.

there's a clear implication of a metaphoric relationship vampire-victim as for Alonso-Hoyt...as they go along, Hoyt has no choice but do delv more and more into the dark world of Alonso, and as a Drakula, protected by an amulet of some sort, when the badge is removed, he's out of powers, a common man, like anyone else. The stroke of a new day, midnight comes, and he's totally mortal and fulgored not by daylight, but by bullets.
Hoyt denied being taken to the the vampiresque universe, he's not a victim, he refuses it, and he breaks free from the vampire attempt by Alonso to turn him into his zombie.
Look at how insistent he is on keeping Hoyt with him when it's clear he's totally against it.

Only after noticeing he's not corruptble, Alonso is delivered to the vampire hunters - those latin gangsters who think he's indeed a vampire when they found the girl's wallet with him. Only when he tells the truth he's not only freed but also 'baptized' (look at the tub) and becomes, 'de facto' a vampire hunter who captures Alonso and leaves him to die at the light of day (midnight and the russians).

Unless the author/writer/director sheds light on this, I guess we'll never know. Could go either way - either Hoyt was always set for a fall no matter what he did (even if he did take a share + kill Roger), or Alonzo would have taken Hoyt in if Hoyt was open to being crooked.

What I would say though is that on the balance of probabilities, given Alonzo's personality/character, I think it's more likely he'd have gotten Hoyt killed, mainly because even if Hoyt had shot Roger, took his share of the cash, etc, I don't think Alonzo would know enough about Hoyt to trust him in the long term (e.g. what's to stop Hoyt feeling guilty and depressed, and turning himself in a week, or month, or year later? Or what's to stop Hoyt from blackmailing Alonzo down the line?). So I think the plan was always to have the Latino gang kill Hoyt. That way things are even more "complete" for Alonzo - Hoyt takes drugs, kills Roger, hangs out and gets killed by a Latino gang, and investigations into Roger's shooting will guarantee to never go anywhere because the shooter is now dead.

He was acting the entire time. He needed to pay off Russians. He found a chance to set up a rookie cop. He was a piece of *beep* from start to finish.

He was planning on Hoyt to become a team member, however at the house he realized Jake couldn't be corrupted to the extent he needed to. He managed to get him to smoke PCP, Drink, Serve False Warrants, Jack suspects for there drugs all in one day, he also saw him use that illegal choke hold doing what he had to do. However he couldn't get him to commit what he needed most, murder. Hence he decided to call up the eses and have them take Jake out in order to protect himself from the repercussions should he ever try and raise questions of Alonzos corrupt actions.

Yes definitely (planned for a week before...), but I do believe if Hoyt had accepted his ways, Alonzo would have liked it.
It's just that Alonzo didn't want him to be able to make the choice freely...

Yes, Alonzo even said it After they killed Roger

The former.