Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If your opponent's monster attacks, during damage calculation (Quick Effect): You can discard this card; the damage you take from that battle is halved. When your opponent activates an effect that would inflict damage to you (even during the Damage Step) (Quick Effect): You can discard this card; the damage you take from that effect is halved. If this card is sent from the field to the GY: You can add 1 "Gouki" card from your Deck to your hand, except "Gouki Octostretch". You can only use this effect of "Gouki Octostretch" once per turn.
--剛鬼マンジロック
--Gouki Octostretch
local s,id=GetID()
function s.initial_effect(c)
	--Halve damage
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetType(EFFECT_TYPE_QUICK_O)
	e1:SetRange(LOCATION_HAND)
	e1:SetCode(EVENT_PRE_DAMAGE_CALCULATE)
	e1:SetCondition(s.damcon)
	e1:SetCost(Cost.SelfDiscard)
	e1:SetOperation(s.damop)
	c:RegisterEffect(e1)
	--Halve damage
	local e2=Effect.CreateEffect(c)
	e2:SetDescription(aux.Stringid(id,1))
	e2:SetType(EFFECT_TYPE_QUICK_O)
	e2:SetCode(EVENT_CHAINING)
	e2:SetRange(LOCATION_HAND)
	e2:SetProperty(EFFECT_FLAG_DAMAGE_STEP+EFFECT_FLAG_DAMAGE_CAL)
	e2:SetCondition(aux.damcon1)
	e2:SetCost(Cost.SelfDiscard)
	e2:SetOperation(s.operation)
	c:RegisterEffect(e2)
	--Add to hand
	local e3=Effect.CreateEffect(c)
	e3:SetDescription(aux.Stringid(id,2))
	e3:SetCategory(CATEGORY_TOHAND+CATEGORY_SEARCH)
	e3:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_O)
	e3:SetProperty(EFFECT_FLAG_DELAY)
	e3:SetCode(EVENT_TO_GRAVE)
	e3:SetCountLimit(1,id)
	e3:SetCondition(s.thcon)
	e3:SetTarget(s.thtg)
	e3:SetOperation(s.thop)
	c:RegisterEffect(e3)
end
s.listed_series={SET_GOUKI}
function s.damcon(e,tp,eg,ep,ev,re,r,rp)
	return Duel.GetBattleDamage(tp)>0 and Duel.GetAttacker()~=tp
end
function s.damop(e,tp,eg,ep,ev,re,r,rp)
	local e1=Effect.CreateEffect(e:GetHandler())
	e1:SetType(EFFECT_TYPE_FIELD)
	e1:SetCode(EFFECT_CHANGE_BATTLE_DAMAGE)
	e1:SetProperty(EFFECT_FLAG_PLAYER_TARGET)
	e1:SetTargetRange(1,0)
	e1:SetValue(HALF_DAMAGE)
	e1:SetReset(RESET_PHASE|PHASE_DAMAGE)
	Duel.RegisterEffect(e1,tp)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	local cid=Duel.GetChainInfo(ev,CHAININFO_CHAIN_ID)
	local e1=Effect.CreateEffect(e:GetHandler())
	e1:SetType(EFFECT_TYPE_FIELD)
	e1:SetCode(EFFECT_CHANGE_DAMAGE)
	e1:SetProperty(EFFECT_FLAG_PLAYER_TARGET)
	e1:SetTargetRange(1,0)
	e1:SetLabel(cid)
	e1:SetValue(s.damcon2)
	e1:SetReset(RESET_CHAIN)
	Duel.RegisterEffect(e1,tp)
end
function s.damcon2(e,re,val,r,rp,rc)
		local cc=Duel.GetCurrentChain()
	if cc==0 or (r&REASON_EFFECT)==0 then return end
	local cid=Duel.GetChainInfo(0,CHAININFO_CHAIN_ID)
	return cid==e:GetLabel() and math.ceil(val/2) or val
end
function s.thcon(e,tp,eg,ep,ev,re,r,rp)
	return e:GetHandler():IsPreviousLocation(LOCATION_ONFIELD)
end
function s.thfilter(c)
	return c:IsSetCard(SET_GOUKI) and not c:IsCode(id) and c:IsAbleToHand()
end
function s.thtg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.thfilter,tp,LOCATION_DECK,0,1,nil) end
	Duel.SetOperationInfo(0,CATEGORY_TOHAND,nil,1,tp,LOCATION_DECK)
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