Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
If your opponent controls a monster and all face-up monsters you control (min. 1) are Level 4, you can Special Summon this card (from your hand). You can only Special Summon "Doggy Diver" once per turn this way. This card cannot be used as an Xyz Material for an Xyz Summon, except for the Xyz Summon of a Warrior-Type monster.
--トラブル・ダイバー
--Doggy Diver
local s,id=GetID()
function s.initial_effect(c)
	--special summon
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_FIELD)
	e1:SetCode(EFFECT_SPSUMMON_PROC)
	e1:SetProperty(EFFECT_FLAG_UNCOPYABLE)
	e1:SetRange(LOCATION_HAND)
	e1:SetCountLimit(1,id,EFFECT_COUNT_CODE_OATH)
	e1:SetCondition(s.spcon)
	c:RegisterEffect(e1)
	--xyzlimit
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_SINGLE)
	e2:SetCode(EFFECT_CANNOT_BE_XYZ_MATERIAL)
	e2:SetProperty(EFFECT_FLAG_CANNOT_DISABLE+EFFECT_FLAG_UNCOPYABLE)
	e2:SetValue(s.xyzlimit)
	c:RegisterEffect(e2)
end
function s.spcon(e,c)
	if c==nil then return true end
	local tp=c:GetControler()
	local g=Duel.GetMatchingGroup(Card.IsFaceup,tp,LOCATION_MZONE,0,nil)
	return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and Duel.GetFieldGroupCount(tp,LOCATION_MZONE,0)>0
		and Duel.GetFieldGroupCount(tp,0,LOCATION_MZONE)>0
		and g:IsExists(aux.FaceupFilter(Card.IsLevel,4),1,nil)
		and not g:IsExists(aux.NOT(aux.FaceupFilter(Card.IsLevel,4)),1,nil)
end
function s.xyzlimit(e,c)
	if not c then return false end
	return not c:IsRace(RACE_WARRIOR)
end