Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
Activate 1 of these effects. ● Add 1 "Gravekeeper's" monster from your Deck to your hand. ● Immediately after this effect resolves, Normal Summon 1 "Gravekeeper's" monster. You can only activate 1 "Necrovalley Throne" per turn.
--ネクロバレーの玉座
--Necrovalley Throne
--scripted by Naim
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	e1:SetCountLimit(1,id,EFFECT_COUNT_CODE_OATH)
	e1:SetTarget(s.target)
	c:RegisterEffect(e1)
end
s.listed_series={SET_GRAVEKEEPERS}
function s.thfilter(c)
	return c:IsSetCard(SET_GRAVEKEEPERS) and c:IsMonster() and c:IsAbleToHand()
end
function s.nsfilter(c)
	return c:IsSetCard(SET_GRAVEKEEPERS) and c:IsSummonable(true,nil)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	local b1=Duel.IsExistingMatchingCard(s.thfilter,tp,LOCATION_DECK,0,1,nil)
	local b2=Duel.IsExistingMatchingCard(s.nsfilter,tp,LOCATION_HAND,0,1,nil)
	if chk==0 then return b1 or b2 end
	local op=0
	if b1 and b2 then
		op=Duel.SelectOption(tp,aux.Stringid(id,0),aux.Stringid(id,1))
	elseif b1 then
		op=Duel.SelectOption(tp,aux.Stringid(id,0))
	else
		op=Duel.SelectOption(tp,aux.Stringid(id,1))+1
	end
	e:SetLabel(op)
	if op==0 then
		e:SetCategory(CATEGORY_TOHAND+CATEGORY_SEARCH)
		e:SetProperty(0)
		local g=Duel.GetMatchingGroup(s.thfilter,tp,LOCATION_DECK,0,nil)
		e:SetOperation(s.thop)
		Duel.SetOperationInfo(0,CATEGORY_TOHAND,nil,1,tp,LOCATION_DECK)
	else
		e:SetCategory(CATEGORY_SUMMON)
		e:SetProperty(0)
		e:SetOperation(s.nsop)
		Duel.SetOperationInfo(0,CATEGORY_SUMMON,nil,1,0,0)
	end
end
function s.nsop(e,tp,eg,ep,ev,re,r,rp)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_SUMMON)
	local g=Duel.SelectMatchingCard(tp,s.nsfilter,tp,LOCATION_HAND,0,1,1,nil)
	local tc=g:GetFirst()
	if tc then
		Duel.Summon(tp,tc,true,nil)
	end
end
function s.thop(e,tp,eg,ep,ev,re,r,rp)
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_ATOHAND)
	local g=Duel.SelectMatchingCard(tp,s.thfilter,tp,LOCATION_DECK,0,1,1,nil)
	if #g>0 then
		Duel.SendtoHand(g,nil,REASON_EFFECT)
		Duel.ConfirmCards(1-tp,g)
	end
end