Lua Cancel event

[Caio Cesar]

local config = {
cooldown = 5, -- tempo entre uma magia e outra
tempo = 20, -- tempo em segundos que ficará healando
percent = 2, --- porcentagem da vida que cura
storage = 45382

}

function onCastSpell(cid, var)

local p = Creature(cid)
if os.time() - p:getStorageValue(cid, config.storage) >= config.cooldown then
for i = 1, config.tempo do
addEvent(function()



 local lifedraw = math.ceil(p:getMaxHealth() * (config.percent)/100)
 local pos = p:getPosition()
  p:addHealth(cid, lifedraw, 1)     
        pos:sendMagicEffect(13)
             

end, 1000*i)
end

p:setStorageValue(cid, config.storage, os.time())

else
p:sendCancelMessage(cid, "Your Mass Healing is at cooldown, you must wait "..(config.cooldown - (os.time() - p:getStorageValue(cid, config.storage))).." seconds.")
end
return true
end

I did this spell , a heal over time, but if the player logout while the effect is on, my server crash.
How i can cancel a effect/event/etc over time if a player logout??

 

[Kiriito]

the spell is not healing here O,o

 

[Ninja]

local config = {
    cooldown = 5, -- tempo entre uma magia e outra
    tempo = 20, -- tempo em segundos que ficará healando
    percent = 2, --- porcentagem da vida que cura
    storage = 45382
}

function onCastSpell(creature, var)
    if os.time() - creature:getStorageValue(config.storage) < config.cooldown then
        creature:sendCancelMessage("Your Mass Healing is at cooldown, you must wait "..(config.cooldown - (os.time() - creature:getStorageValue(config.storage))).." seconds.")
        return false
    end

    for i = 1, config.tempo do
        addEvent(function (cid)
            local creature = Creature(cid)
            if not creature then
                return true
            end

            local lifedraw = math.ceil(creature:getMaxHealth() * (config.percent) / 100)
            creature:addHealth(lifedraw)   
            creature:getPosition():sendMagicEffect(CONST_ME_MAGIC_BLUE)
        end, 1000 * i, creature:getId())
    end

    creature:setStorageValue(config.storage, os.time())
    return true
end

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