Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When this card is activated: You can add 1 "Subterror" monster from your Deck to your hand. Once per turn: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position. Once per turn, when an opponent's monster declares an attack: You can change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position, then you can negate the attack. You can only activate 1 "The Hidden City" per turn.
--地中界シャンバラ
--The Hidden City
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,1))
	e1:SetCategory(CATEGORY_TOHAND+CATEGORY_SEARCH)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetCountLimit(1,id,EFFECT_COUNT_CODE_OATH)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
	--Change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(id,1))
	e2:SetCategory(CATEGORY_POSITION)
	e2:SetType(EFFECT_TYPE_IGNITION)
	e2:SetRange(LOCATION_FZONE)
	e2:SetCountLimit(1)
	e2:SetTarget(s.postg)
	e2:SetOperation(s.posop)
	c:RegisterEffect(e2)
	--Change 1 face-down Defense Position "Subterror" monster you control to face-up Attack or Defense Position, then you can negate an opponent's monster's attack
	local e3=Effect.CreateEffect(c)
	e3:SetCategory(CATEGORY_POSITION)
	e3:SetType(EFFECT_TYPE_FIELD+EFFECT_TYPE_TRIGGER_O)
	e3:SetCode(EVENT_ATTACK_ANNOUNCE)
	e3:SetRange(LOCATION_FZONE)
	e3:SetCountLimit(1)
	e3:SetCondition(s.condition)
	e3:SetTarget(s.target)
	e3:SetOperation(s.operation)
	c:RegisterEffect(e3)
end
function s.thfilter(c)
	return c:IsMonster() and c:IsSetCard(SET_SUBTERROR) and c:IsAbleToHand()
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	local g=Duel.GetMatchingGroup(s.thfilter,tp,LOCATION_DECK,0,nil)
	if #g>0 and Duel.SelectYesNo(tp,aux.Stringid(id,0)) then
		Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_ATOHAND)
		local sg=g:Select(tp,1,1,nil)
		Duel.SendtoHand(sg,nil,REASON_EFFECT)
		Duel.ConfirmCards(1-tp,sg)
	end
end
function s.filter(c)
	return c:IsSetCard(SET_SUBTERROR) and c:IsFacedown() and c:IsDefensePos()
end
function s.postg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.filter,tp,LOCATION_MZONE,0,1,nil) end
	Duel.SetOperationInfo(0,CATEGORY_POSITION,nil,1,0,0)
end
function s.posop(e,tp,eg,ep,ev,re,r,rp,chk)
	if not e:GetHandler():IsRelateToEffect(e) then return end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_POSCHANGE)
	local g=Duel.SelectMatchingCard(tp,s.filter,tp,LOCATION_MZONE,0,1,1,nil)
	local tc=g:GetFirst()
	if tc then
		local pos=Duel.SelectPosition(tp,tc,POS_FACEUP_ATTACK+POS_FACEUP_DEFENSE)
		Duel.ChangePosition(tc,pos)
	end
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	return Duel.IsTurnPlayer(1-tp)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.filter,tp,LOCATION_MZONE,0,1,nil) end
	Duel.SetOperationInfo(0,CATEGORY_POSITION,nil,1,0,0)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_POSCHANGE)
	local tc=Duel.SelectMatchingCard(tp,s.filter,tp,LOCATION_MZONE,0,1,1,nil):GetFirst()
	if tc then
		local pos=Duel.SelectPosition(tp,tc,POS_FACEUP_ATTACK+POS_FACEUP_DEFENSE)
		if Duel.ChangePosition(tc,pos)~=0 and Duel.SelectYesNo(tp,aux.Stringid(id,2)) then
			Duel.BreakEffect()
			Duel.NegateAttack()
		end
	end
end