Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If a face-up "HERO" monster(s) you control is destroyed by battle or card effect: Special Summon 1 Level 4 or lower "Vision HERO" monster from your Deck, then you can halve the original ATK/DEF of 1 monster your opponent controls. You can only activate 1 "Apparition" per turn.
--出幻
--Apparition
--Scripted by Larry126
local s,id=GetID()
function s.initial_effect(c)
	--Special Summon 1 Level 4 or lower "Vision HERO" monster from your Deck, then you can halve the original ATK/DEF of 1 monster your opponent controls
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_SPECIAL_SUMMON+CATEGORY_ATKCHANGE+CATEGORY_DEFCHANGE)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetProperty(EFFECT_FLAG_DELAY+EFFECT_FLAG_DAMAGE_STEP)
	e1:SetCode(EVENT_DESTROYED)
	e1:SetCountLimit(1,id,EFFECT_COUNT_CODE_OATH)
	e1:SetCondition(s.condition)
	e1:SetTarget(s.target)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
s.listed_series={SET_HERO,SET_VISION_HERO}
function s.confilter(c,tp)
	return c:IsPreviousSetCard(SET_HERO) and c:IsPreviousControler(tp) and c:IsPreviousLocation(LOCATION_MZONE) and c:IsPreviousPosition(POS_FACEUP)
		and c:IsReason(REASON_BATTLE|REASON_EFFECT)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	return eg:IsExists(s.confilter,1,nil,tp)
end
function s.spfilter(c,e,tp)
	return c:IsLevelBelow(4) and c:IsSetCard(SET_VISION_HERO) and c:IsCanBeSpecialSummoned(e,0,tp,false,false)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and Duel.IsExistingMatchingCard(s.spfilter,tp,LOCATION_DECK,0,1,nil,e,tp) end
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,nil,1,tp,LOCATION_DECK)
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	if Duel.GetLocationCount(tp,LOCATION_MZONE)<=0 then return end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_SPSUMMON)
	local g=Duel.SelectMatchingCard(tp,s.spfilter,tp,LOCATION_DECK,0,1,1,nil,e,tp)
	if #g>0 and Duel.SpecialSummon(g,0,tp,tp,false,false,POS_FACEUP)>0
		and Duel.IsExistingMatchingCard(Card.IsFaceup,tp,0,LOCATION_MZONE,1,nil)
		and Duel.SelectYesNo(tp,aux.Stringid(id,1)) then
		Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_ATKDEF)
		local sc=Duel.SelectMatchingCard(tp,Card.IsFaceup,tp,0,LOCATION_MZONE,1,1,nil):GetFirst()
		if not sc then return end
		Duel.HintSelection(sc)
		Duel.BreakEffect()
		--Its original ATK/DEF is halved
		local e1=Effect.CreateEffect(e:GetHandler())
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetProperty(EFFECT_FLAG_CANNOT_DISABLE)
		e1:SetCode(EFFECT_SET_BASE_ATTACK)
		e1:SetValue(sc:GetBaseAttack()/2)
		e1:SetReset(RESET_EVENT|RESETS_STANDARD)
		sc:RegisterEffect(e1)
		local e2=e1:Clone()
		e2:SetCode(EFFECT_SET_BASE_DEFENSE)
		e2:SetValue(sc:GetBaseDefense()/2)
		sc:RegisterEffect(e2)
	end
end