Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
1 "Knightmare" monster, except "Knightmare Mermaid" If this card is Link Summoned: You can discard 1 card; Special Summon 1 "Knightmare" monster from your Deck, then, if this card was co-linked when this effect was activated, you can draw 1 card. You can only use this effect of "Knightmare Mermaid" once per turn. Monsters on the field lose 1000 ATK/DEF, unless they are co-linked.
--トロイメア・マーメイド
--Knightmare Mermaid
local s,id=GetID()
function s.initial_effect(c)
	c:EnableReviveLimit()
	--Link Summon procedure
	Link.AddProcedure(c,s.matfilter,1,1)
	--Special Summon 1 "Knightmare" from your Deck
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_O)
	e1:SetCode(EVENT_SPSUMMON_SUCCESS)
	e1:SetCountLimit(1,id)
	e1:SetCondition(s.spcon)
	e1:SetCost(s.spcost)
	e1:SetTarget(s.sptg)
	e1:SetOperation(s.spop)
	c:RegisterEffect(e1)
	--Decrease ATK/DEF
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_FIELD)
	e2:SetCode(EFFECT_UPDATE_ATTACK)
	e2:SetRange(LOCATION_MZONE)
	e2:SetTargetRange(LOCATION_MZONE,LOCATION_MZONE)
	e2:SetTarget(function(_,c) return c:GetMutualLinkedGroupCount()==0 end)
	e2:SetValue(-1000)
	c:RegisterEffect(e2)
	local e3=e2:Clone()
	e3:SetCode(EFFECT_UPDATE_DEFENSE)
	c:RegisterEffect(e3)
end
s.listed_series={SET_KNIGHTMARE}
function s.matfilter(c,lc,sumtype,tp)
	return c:IsSetCard(SET_KNIGHTMARE,lc,sumtype,tp) and not c:IsSummonCode(lc,sumtype,tp,id)
end
function s.spcon(e,tp,eg,ep,ev,re,r,rp)
	return e:GetHandler():IsLinkSummoned()
end
function s.spcost(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(Card.IsDiscardable,tp,LOCATION_HAND,0,1,nil) end
	Duel.DiscardHand(tp,Card.IsDiscardable,1,1,REASON_COST|REASON_DISCARD)
end
function s.spfilter(c,e,tp)
	return c:IsSetCard(SET_KNIGHTMARE) and c:IsCanBeSpecialSummoned(e,0,tp,false,false)
end
function s.sptg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and Duel.IsExistingMatchingCard(s.spfilter,tp,LOCATION_DECK,0,1,nil,e,tp) end
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,nil,1,tp,LOCATION_DECK)
	if e:GetHandler():GetMutualLinkedGroupCount()>0 then
		e:SetLabel(1)
	else
		e:SetLabel(0)
	end
	local cat=CATEGORY_SPECIAL_SUMMON
	if e:GetLabel()==1 then cat=cat+CATEGORY_DRAW end
	e:SetCategory(cat)
end
function s.spop(e,tp,eg,ep,ev,re,r,rp)
	if Duel.GetLocationCount(tp,LOCATION_MZONE)<=0 then return end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_SPSUMMON)
	local g=Duel.SelectMatchingCard(tp,s.spfilter,tp,LOCATION_DECK,0,1,1,nil,e,tp)
	if #g>0 and Duel.SpecialSummon(g,0,tp,tp,false,false,POS_FACEUP)~=0
		and e:GetLabel()==1 and Duel.IsPlayerCanDraw(tp,1)
		and Duel.SelectYesNo(tp,aux.Stringid(id,1)) then
		Duel.BreakEffect()
		Duel.ShuffleDeck(tp)
		Duel.Draw(tp,1,REASON_EFFECT)
	end
end