【进阶实战】双倍经验卡：倍率挂载与到点回滚的封装

local function useExpCard(actor)
    actor = getplayerbyname(actor)
    if not takeitem(actor, "双倍经验卡", 1) then
        sendmsg(actor, 1, "背包里没有双倍经验卡。")
        return
    end
    local now = os.time()
    local oldEnd = tonumber(getplayvar(actor, "HUMAN", "ExpCardEnd")) or 0
    local newEnd = (oldEnd > now and oldEnd or now) + 3600
    mapkillmonexprate(actor, "*", 200)
    setplayvar(actor, "HUMAN", "ExpCardEnd", newEnd, 1)
    setontimer(actor, 21, newEnd - now, 1, 1)
    sendmsg(actor, 1, "双倍经验已生效，剩余 " .. (newEnd - now) .. " 秒。")
end

local function ontimer21(actor)
    actor = getplayerbyname(actor)
    local endAt = tonumber(getplayvar(actor, "HUMAN", "ExpCardEnd")) or 0
    if os.time() < endAt then
        setontimer(actor, 21, endAt - os.time(), 1, 1)
        return
    end
    mapkillmonexprate(actor, "*", 0)
    setplayvar(actor, "HUMAN", "ExpCardEnd", 0, 1)
    sendmsg(actor, 1, "双倍经验已到期，倍率恢复正常。")
end