## Counter: When the target takes HP damage, deals the same amount back to the source.
## Uses event interception to detect HP reductions.
extends EffectBase

func on_stat_base(ctx: EffectCtx, evt: StatBaseEvent) -> void:
	var stat_def: StatDef = ctx.target.get_context().get_stat_def_by_id(evt.stat_def_id)
	if not stat_def or stat_def.get_name() != "hp":
		return
	if evt.combatant_id != ctx.target.get_id():
		return
	if ctx.source == null:
		return
	var current_hp: int = ctx.target.get_stat("hp").get_value()
	var diff: int = current_hp - evt.value
	if diff > 0:
		var source_hp: Stat = ctx.source.get_stat("hp")
		source_hp.sub_base(diff)