Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When your opponent activates a Spell Card that targets exactly 1 monster (and no other cards) on the field: Target another card that would be an appropriate target; that Spell now targets the new target.
--天使の手鏡
--Fairy's Hand Mirror
local s,id=GetID()
function s.initial_effect(c)
	--activate
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetProperty(EFFECT_FLAG_CARD_TARGET)
	e1:SetCode(EVENT_CHAINING)
	e1:SetCondition(s.tgcon)
	e1:SetTarget(s.tgtg)
	e1:SetOperation(s.tgop)
	c:RegisterEffect(e1)
end
function s.tgcon(e,tp,eg,ep,ev,re,r,rp)
	if rp==tp or not re:IsHasType(EFFECT_TYPE_ACTIVATE) or not re:IsSpellEffect()
		or not re:IsHasProperty(EFFECT_FLAG_CARD_TARGET) then return false end
	local g=Duel.GetChainInfo(ev,CHAININFO_TARGET_CARDS)
	if not g or #g~=1 then return false end
	local tc=g:GetFirst()
	e:SetLabelObject(tc)
	return tc:IsLocation(LOCATION_MZONE)
end
function s.filter(c,ct)
	return Duel.CheckChainTarget(ct,c)
end
function s.tgtg(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	if chkc then return chkc~=e:GetLabelObject() and chkc:IsLocation(LOCATION_MZONE) and s.filter(chkc,ev) end
	if chk==0 then return Duel.IsExistingTarget(s.filter,tp,LOCATION_MZONE,LOCATION_MZONE,1,e:GetLabelObject(),ev) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_TARGET)
	Duel.SelectTarget(tp,s.filter,tp,LOCATION_MZONE,LOCATION_MZONE,1,1,e:GetLabelObject(),ev)
end
function s.tgop(e,tp,eg,ep,ev,re,r,rp)
	local g=Duel.GetChainInfo(0,CHAININFO_TARGET_CARDS)
	if g:GetFirst():IsRelateToEffect(e) then
		Duel.ChangeTargetCard(ev,g)
	end
end