Gen7Data/Scripts/Moves/Drain.as

namespace Gen7 {
    [Move effect=drain]
    shared class DrainMove : PkmnScript{
        private float _healModifier = 0;

        void OnInitialize(const narray<EffectParameter@>@ parameters) override {
            _healModifier = parameters[0].AsFloat();
        }

        void OnSecondaryEffect(ExecutingMove@ attack, Pokemon@ target, uint8 hit) override {
            auto hitData = attack.GetHitData(target, hit);
            auto damage = hitData.Damage;
            float mod = _healModifier;
            if (attack.User.HasHeldItem("big_root")){
                mod *= 1.3;
            }
            attack.User.Heal(uint(damage * mod));
        }
    }
}