cannibalize alteration

i am trying to make an ability based upon cannibalize which allows units to eat corpses and gain mana from them instead of HP. I checked in the spell editor and there was no data field for it. Does anyone know how to do this through triggering?

This is just a pseudo code
This would take 4 variable and 5 triggers
Real variable = cannibalizeManaLevel = 0
Unit variable = cannibalizeManaCaster = noUnit
boolean variable = cannibalizeing = false
cannibalizeManaLevel
cannibalizeMana
cannibalizeManaON
cannibalizeManaMoveTest
cannibalizeManaAttackTest

cannibalizeManaLevel (this trigger must be in JASS in order for the condition to check the correct learned spell)
Event - Hero learns a skill
Condition - learned skill equal to (<your spell's 4 letter code here {ex. A001}>)
Actions - set cannibalizeManaLevel = cannibalizeManaLevel + 1

cannibalizeMana
Event - A unit is issued an order with no target.
Condition - (issued order) equal to (<the cannabalize order>)
Actions - if(cannibalizing equal to false)
TurnON(cannibalizeManaON) else textmessage - "You are already cannibalizing a unit"
cannibalizing = true
wait (<however long you want it to last>)
turnOFF(cannibalizeManaON)
cannibalizing = false

cannibalizeManaON
Event - every 5.5 - cannibalizeManaLevel
Actions - set mana of cannibalizeManaCaster = mana of cannibalizeManaCaster + 5 X cannibalizeManaLevel

cannibalizeManaMoveTest
Event - A unit is issued an order targeting a point
Condition - ordered unit equal to cannibalizeManaCaster
cannibalizing = true
Actions - turnOFF(cannibalizeManaON)
set cannibalizing = false

cannibalizeManaAttackTest
Event - A unit is issued an order targeting an object
Condition - ordered unit equal to cannibalizeManaCaster
cannibalizing = true
Actions - turnOFF(cannibalizeManaON)
set cannibalizing = false

(unless it is a hero spell with levels you don't need the levels variable or trigger. Is this too jumbled?)

the ability is going to be a normal unit ability. It will be enabled for all the heroes of my AoS Style map(there are 16 heroes) but it is going to need an upgrade to be researched. I understand how to do the upgrade stuff but what i am wondering is how many more variables would i need for 16 heroes? Could i just do an array? Also, how do i convert the trigger into JASS?