Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When your opponent activates a card or effect in response to the activation of your "Generaider" card or effect: You can discard 1 card; your opponent's activated effect becomes "each player draws 1 card". You can only use this effect of "Generaider Boss Room" once per turn.
--王の支配
--Generaider Boss Room
--original script by andré
local s,id=GetID()
function s.initial_effect(c)
	--activate
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	c:RegisterEffect(e1)
	--instant(chain)
	local e2=Effect.CreateEffect(c)
	e2:SetCountLimit(1,id)
	e2:SetDescription(aux.Stringid(id,1))
	e2:SetType(EFFECT_TYPE_ACTIVATE)
	e2:SetCode(EVENT_CHAINING)
	e2:SetCost(s.cost)
	e2:SetCondition(s.condition)
	e2:SetTarget(s.target)
	e2:SetOperation(s.operation)
	c:RegisterEffect(e2)
	local e3=e2:Clone()
	e3:SetType(EFFECT_TYPE_QUICK_O)
	e3:SetRange(LOCATION_SZONE)
	c:RegisterEffect(e3)
end
s.listed_series={SET_GENERAIDER}
function s.cost(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(Card.IsDiscardable,tp,LOCATION_HAND,0,1,e:GetHandler()) end
	Duel.DiscardHand(tp,Card.IsDiscardable,1,1,REASON_COST|REASON_DISCARD)
end
function s.condition(e,tp,eg,ep,ev,re,r,rp)
	local ch=Duel.GetCurrentChain(true)-1
	return ep==1-tp and ch>0 and Duel.GetChainInfo(ch,CHAININFO_TRIGGERING_CONTROLER)==tp
		and Duel.GetChainInfo(ch,CHAININFO_TRIGGERING_EFFECT):GetHandler():IsSetCard(SET_GENERAIDER)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsPlayerCanDraw(tp,1) and Duel.IsPlayerCanDraw(1-tp,1) end
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	local g=Group.CreateGroup()
	Duel.ChangeTargetCard(ev,g)
	Duel.ChangeChainOperation(ev,s.repop)
end
function s.repop(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	Duel.Draw(tp,1,REASON_EFFECT)
	Duel.Draw(1-tp,1,REASON_EFFECT)
	if e:IsSpellTrapEffect() and e:IsHasType(EFFECT_TYPE_ACTIVATE) then
		c:CancelToGrave(false)
	end
end