Generate a YGOPro Lua script for the following Yu-Gi-Oh card effect:
When this card is Normal or Special Summoned: You can excavate the top card of your Deck, and if it is a Plant-Type monster, send it to the Graveyard. Otherwise, place it on the bottom of your Deck. If this card is excavated from the Deck and sent to the Graveyard by a card effect: You can target 1 Level 4 or lower Plant-Type monster in your Graveyard; Special Summon that target. You can only use this effect of "Sylvan Peaskeeper" once per turn.
--森羅の実張り ピース
--Sylvan Peaskeeper
local s,id=GetID()
function s.initial_effect(c)
	--Excavate the top card of your Deck
	local e1=Effect.CreateEffect(c)
	e1:SetDescription(aux.Stringid(id,0))
	e1:SetCategory(CATEGORY_DECKDES)
	e1:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_O)
	e1:SetProperty(EFFECT_FLAG_DAMAGE_STEP)
	e1:SetCode(EVENT_SUMMON_SUCCESS)
	e1:SetTarget(s.target)
	e1:SetOperation(s.operation)
	c:RegisterEffect(e1)
	local e2=e1:Clone()
	e2:SetCode(EVENT_SPSUMMON_SUCCESS)
	c:RegisterEffect(e2)
	--Special Summon 1 Level 4 or lower Plant monster from the GY
	local e3=Effect.CreateEffect(c)
	e3:SetDescription(aux.Stringid(id,1))
	e3:SetCategory(CATEGORY_SPECIAL_SUMMON)
	e3:SetType(EFFECT_TYPE_SINGLE+EFFECT_TYPE_TRIGGER_O)
	e3:SetProperty(EFFECT_FLAG_CARD_TARGET+EFFECT_FLAG_DELAY)
	e3:SetCode(EVENT_TO_GRAVE)
	e3:SetCountLimit(1,id)
	e3:SetCondition(s.spcon)
	e3:SetTarget(s.sptg)
	e3:SetOperation(s.spop)
	c:RegisterEffect(e3)
end
function s.target(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsPlayerCanDiscardDeck(tp,1) end
end
function s.operation(e,tp,eg,ep,ev,re,r,rp)
	if not Duel.IsPlayerCanDiscardDeck(tp,1) then return end
	Duel.ConfirmDecktop(tp,1)
	local g=Duel.GetDecktopGroup(tp,1)
	local tc=g:GetFirst()
	if tc:IsRace(RACE_PLANT) then
		Duel.DisableShuffleCheck()
		Duel.SendtoGrave(g,REASON_EFFECT|REASON_EXCAVATE)
	else
		Duel.MoveSequence(tc,1)
	end
end
function s.spcon(e,tp,eg,ep,ev,re,r,rp)
	local c=e:GetHandler()
	return c:IsPreviousLocation(LOCATION_DECK) and c:IsReason(REASON_EXCAVATE)
end
function s.filter(c,e,tp)
	return c:IsLevelBelow(4) and c:IsRace(RACE_PLANT) and c:IsCanBeSpecialSummoned(e,0,tp,false,false)
end
function s.sptg(e,tp,eg,ep,ev,re,r,rp,chk,chkc)
	if chkc then return chkc:IsLocation(LOCATION_GRAVE) and chkc:IsControler(tp) and s.filter(chkc,e,tp) end
	if chk==0 then return Duel.GetLocationCount(tp,LOCATION_MZONE)>0
		and Duel.IsExistingTarget(s.filter,tp,LOCATION_GRAVE,0,1,nil,e,tp) end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_SPSUMMON)
	local g=Duel.SelectTarget(tp,s.filter,tp,LOCATION_GRAVE,0,1,1,nil,e,tp)
	Duel.SetOperationInfo(0,CATEGORY_SPECIAL_SUMMON,g,1,0,0)
end
function s.spop(e,tp,eg,ep,ev,re,r,rp)
	local tc=Duel.GetFirstTarget()
	if tc:IsRelateToEffect(e) then
		Duel.SpecialSummon(tc,0,tp,tp,false,false,POS_FACEUP)
	end
end