How does the spells per day/Spells known/Spell prepared work for the Arcanist?[PF]

[13ones]

So I've been shanghai'd into a Pathfinder game using nothing but ACG classes. Since I'm our gaming group's resident Arcane tinkerer I've been tossed the task of playing an Arcanist in our party. I just want to be clear on how many spells I gain per level. As I'm reading it (at least in the ACG version I have) I can know ANY spells, having a 100% flexible spell list day to day, but I can only prepare a handful, and can only cast if I still have spells per day left in those slots. Is this right, or am I totally off base?

[Diachronos]

There was actually a class that worked kind of like the Arcanist in 3.5 called the Spirit Shaman, though they admittedly worked a little differently since they were divine casters.

Here's how I like to think of it:
When you're preparing your spells, you're a Wizard. Your spell choices are limited to what's in your spellbook. You can prepare spells with metamagic feats in higher level slots rather than a higher level spell like any Wizard can.
The key difference is that, unlike a Wizard, you don't want to prepare the same spell (spells with metamagic feats are essentially "different spells" for this part) more than once each day, because...
After you've prepared your spells, you're a Sorcerer, and the spells you've prepared are now effectively your Spells Known. You can cast a lot of different spells, or you can just burn all of your 3rd level spell slots to spam Fireball even though you prepared 4 other level 3 spells for the day. You can still add metamagic feats to spells after you've prepared them, it just increases the casting time the same way that it would for a spontaneous caster.

Essentially, you're a Sorcerer (spontaneous caster) who gets to reselect his entire Spells Known each day (when you prepare your spells), except you can only select spells that are recorded in your spellbook.