Help with upgrade items using java script

[petpous 0]

Hi, this is my first post here! First off I would like to say I do have a demo of this game available now on my itchio page here https://wildgypsy.itch.io/summer-solstice

I'm desperately trying to get feedback as the game is part of my A level coursework, thanks. 

Okay, now time for the question I need answering:

So I am making upgrade items for the full game (some are featured in the demo but they are kind of like beta versions)

Basically how they work is I'm using the Yep upgrade item plugin and in the note box for the upgrade items I use this:

<Upgrade Weapon Type: 0>

<Upgrade Effect>

Eval: $gameTemp.reserveCommonEvent(119)

</Upgrade Effect>

Then the common event turns on a switch which triggers a base troop event with looks for the correct scenario to apply the boost (for example at the first turn of the battle a 50% chance of a random enemy being affected with burn or 1% chance of random enemy dying at beginning of the battle just to name a couple) but the problem I have with my script is that the effect is applied immediately after the upgrade is applied to the weapon or armour, however, I only want it in effect if the weapon or armour is equipped. 

In short, what I think I need is a script to check whether the armour or weapon has been equipped or unequipped!

Thanks for your help!