Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
While attacking, this card cannot be destroyed by battle. If this card attacks, after damage calculation, inflict damage equal to half the ATK of the attack target to your opponent.
--ワンショット・ロケット
--Turbo Rocket
local s,id=GetID()
function s.initial_effect(c)
	--damage
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_DAMAGE)
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_F)
	e1:SetCode(EVENT_BATTLED)
	e1:SetCondition(s.condition)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
	--battle indestructable
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_SINGLE)
	e2:SetCode(EFFECT_INDESTRUCTABLE_BATTLE)
	e2:SetCondition(s.indcon)
	e2:SetValue(1)
	c:RegisterEffect(e2)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	return e:GetHandler()==Duel.GetAttacker() and Duel.GetAttackTarget()
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return true end
	local dam=Duel.GetAttackTarget():GetAttack()/2
	Duel.SetTargetPlayer(1-tp)
	Duel.SetTargetParam(dam)
	Duel.SetOperationInfo(0,CATEGORY_DAMAGE,0,0,1-tp,dam)
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	local p=Duel.GetChainInfo(0,CHAININFO_TARGET_PLAYER)
	Duel.Damage(p,Duel.GetAttackTarget():GetAttack()/2,REASON_EFFECT)
end
function s.indcon(e)
	return e:GetHandler()==Duel.GetAttacker()
end