--Sealer Formation
--By Shad3/ fixed for errors by GameMaster
--cleaned up by MLD
Duel.LoadScript("c420.lua")
local s,id=GetID()
function s.initial_effect(c)
	--Activate
	local e1=Effect.CreateEffect(c)
	e1:SetType(EFFECT_TYPE_ACTIVATE)
	e1:SetCode(EVENT_FREE_CHAIN)
	c:RegisterEffect(e1)
	--Add/Draw
	local e2=Effect.CreateEffect(c)
	e2:SetType(EFFECT_TYPE_FIELD+EFFECT_TYPE_TRIGGER_O)
	e2:SetCode(EVENT_PREDRAW)
	e2:SetRange(LOCATION_SZONE)
	e2:SetCondition(s.thcon)
	e2:SetTarget(s.thtg)
	e2:SetOperation(s.thop)
	c:RegisterEffect(e2)
end
function s.thcon(e,tp,eg,ep,ev,re,r,rp)
	return tp==Duel.GetTurnPlayer() and Duel.GetFieldGroupCount(tp,LOCATION_DECK,0)>0 and Duel.GetDrawCount(tp)>0 
end
function s.filter(c)
	return c:IsSeal() and c:IsAbleToHand()
end
function s.thtg(e,tp,eg,ep,ev,re,r,rp,chk)
	if chk==0 then return Duel.IsExistingMatchingCard(s.filter,tp,LOCATION_GRAVE,0,1,nil) end
	local dt=Duel.GetDrawCount(tp)
	if dt~=0 then
		_replace_count=0
		_replace_max=dt
		local e1=Effect.CreateEffect(e:GetHandler())
		e1:SetType(EFFECT_TYPE_FIELD)
		e1:SetProperty(EFFECT_FLAG_PLAYER_TARGET)
		e1:SetCode(EFFECT_DRAW_COUNT)
		e1:SetTargetRange(1,0)
		e1:SetReset(RESET_PHASE+PHASE_DRAW)
		e1:SetValue(0)
		Duel.RegisterEffect(e1,tp)
	end
	Duel.SetOperationInfo(0,CATEGORY_TOHAND,nil,1,tp,LOCATION_GRAVE)
end
function s.thop(e,tp,eg,ep,ev,re,r,rp)
	_replace_count=_replace_count+1
	if _replace_count>_replace_max or not e:GetHandler():IsRelateToEffect(e) or e:GetHandler():IsFacedown() then return end
	Duel.Hint(HINT_SELECTMSG,tp,HINTMSG_ATOHAND)
	local g=Duel.SelectMatchingCard(tp,aux.NecroValleyFilter(s.filter),tp,LOCATION_GRAVE,0,1,1,nil)
	if #g>0 then
		Duel.SendtoHand(g,nil,REASON_EFFECT)
		Duel.ConfirmCards(1-tp,g)
	end
end