Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
During damage calculation, if your Link Monster battles an opponent's monster: Your monster gains ATK equal to the total Levels/Ranks of the monsters it points to x 400, during that damage calculation only. You can only activate 1 "Star Power!!" per turn.
--一曲集中
--Star Power!!
--Scripted by Eerie Code
local s,id=GetID()
function s.initial_effect(c)
	--Targeted link monster gains ATK, equal to total levels/ranks of monsters it points to x 400
	local e1=Effect.CreateEffect(c)
	e1:SetCategory(CATEGORY_ATKCHANGE)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_PRE_DAMAGE_CALCULATE)
	e1:SetCountLimit(1,id,EFFECT_COUNT_CODE_OATH)
	e1:SetCondition(s.condition)
	e1:SetOperation(s.activate)
	c:RegisterEffect(e1)
end
function s.filter(c)
	return c:IsFaceup() and (c:IsLevelAbove(1) or c:IsRankAbove(1))
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	local a=Duel.GetAttacker()
	local d=Duel.GetAttackTarget()
	if a:IsControler(1-tp) then a=Duel.GetAttackTarget() d=Duel.GetAttacker() end
	return a and d and a:IsLinkMonster() and a:GetLinkedGroup():IsExists(s.filter,1,nil)
end
function s.activate(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	local a=Duel.GetAttacker()
	local d=Duel.GetAttackTarget()
	if a:IsControler(1-tp) then a=Duel.GetAttackTarget() end
	if a:IsFaceup() and a:IsRelateToBattle() and d:IsFaceup() and d:IsRelateToBattle() then
		local g=a:GetLinkedGroup():Filter(s.filter,nil)
		if #g==0 then return end
		local tot=0
		for tc in aux.Next(g) do tot=tot+math.max(tc:GetLevel(),tc:GetRank()) end
		local e1=Effect.CreateEffect(c)
		e1:SetType(EFFECT_TYPE_SINGLE)
		e1:SetCode(EFFECT_UPDATE_ATTACK)
		e1:SetValue(tot*400)
		e1:SetReset(RESET_EVENT|RESETS_STANDARD|RESET_PHASE|PHASE_DAMAGE_CAL)
		a:RegisterEffect(e1)
	end
end