Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If this card attacks an opponent's monster, it gains 300 ATK during the Damage Step only. Once per turn, during your End Phase: Send the top 2 cards of your Deck to the Graveyard.
--ライトロード・パラディン ジェイン
--Jain, Lightsworn Paladin
local s,id=GetID()
function s.initial_effect(c)
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_SINGLE)
	e1:SetProperty(EFFECT_FLAG_SINGLE_RANGE)
	e1:SetRange(LOCATION_MZONE)
	e1:SetCode(EFFECT_UPDATE_ATTACK)
	e1:SetCondition(s.condtion)
	e1:SetValue(300)
	c:RegisterEffect(e1)
	--discard deck
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_FIELD+EFFECT_TYPE_TRIGGER_F)
	e2:SetCategory(CATEGORY_DECKDES)
	e2:SetDescription(aux.Stringid(id,0))
	e2:SetCode(EVENT_PHASE+PHASE_END)
	e2:SetRange(LOCATION_MZONE)
	e2:SetCountLimit(1)
	e2:SetCondition(s.discon)
	e2:SetTarget(s.distg)
	e2:SetOperation(s.disop)
	c:RegisterEffect(e2)
end
function s.condtion(e)
	local ph=Duel.GetCurrentPhase()
	return (ph==PHASE_DAMAGE or ph==PHASE_DAMAGE_CAL)
		and Duel.GetAttacker()==e:GetHandler() and Duel.GetAttackTarget()~=nil
end
function s.discon(e,tp,eg,ep,ev,re,r,rp)
	return tp==Duel.GetTurnPlayer()
end
function s.distg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return true end
	Duel.SetOperationInfo(0,CATEGORY_DECKDES,nil,0,tp,2)
end
function s.disop(e,tp,eg,ep,ev,re,r,rp)
	Duel.DiscardDeck(tp,2,REASON_EFFECT)
end