Some html help needed?

I work on the buffy sheet for unisystem. I am a complete html noob. I try to streamline this part: value="/e attacks with @{melee_weapon_name-1}, rolling [[@{melee_weapon_attack_rating-1} + d10]] to hit and [[((@{melee_weapon_damage_base-1} + (@{melee_weapon_twohanded-1})*(@{melee_weapon_damage_Multiplier-1})))*(@{melee_weapon_damage_type-1})]] damage (add @{melee_weapon_damage_type-1} x Success Levels to damage)."></button></th> I need to have a variable for this [[@{melee_weapon_attack_rating-1} + d10]] = var1 and compare it to fixed values and create another variable var2 var1 =1-8 then var2 = 0 var1 =9-10 then var2 = 1 var1 =11-12 then var2 =2 and so on. var2 then needs to be added to the damage like this: [[((@{melee_weapon_damage_base-1} + (@{melee_weapon_twohanded-1})*(@{melee_weapon_damage_Multiplier-1})))*(@{melee_weapon_damage_type-1})]]+ (var2 *  (@{melee_weapon_damage_type-1})) can someone help me with this?

This seems to have little to do with HTML, and is all about how Roll20 macros , dice syntax and the saved attributes works. This is on the advanced side, and I'm not even sure you'd be able to do this with sheetworkers , but might require creating an API to create var2. Someone more knowledgeable with juggling this macro might be able to figure out a way to do this without API, but I suspect sheetworkers are still needed in some form. var1 =1-8 then var2 = 0 var1 =9-10 then var2 = 1 var1 =11-12 then var2 =2 and so on. I assume the pattern will continue with var2 increase by  "1"  for every increase of two on var1?  I.e. "var1= 13-14, then var2=3"

Thank you! I did not know that. The pattern will continue this way: 11-12=2, 13-14=3, 15-16=4 BUT from now on it gets weird 17-20=5, and from now on every 3 so 21-23=6, 24-26=7, 27-29=8 and so on forever.

The unisystem progression makes it probably-impossible to do this without an API script.

any advice how I could get started with the api?