快捷补药：血量告急自动补充药剂

-- 错误：每帧检测直接嗑药，无冷却无上限
function onFrame(p)
    if getplayvar(p, "HP") < 300 then
        useDrug(p, 9801)
    end
end

local THRESH, CD, CAP = 0.3, 5, 10
local function onHpChange(p)
    if getplayvar(p, "HP") / getplayvar(p, "MAXHP")
        >= THRESH then return end
    local now = os.time()
    if now - (tonumber(getplayvar(p, "pillAt") or "0"))
        < CD then return end
    local used = getplayvar(p, "pillUsed") or 0
    if used >= CAP then return end
    local has = getplayvar(p, "drug_9801") or 0
    if has < 1 then
        sendmsg(p, 1, "药剂告罄，请及时补充")
        return
    end
    setplayvar(p, "drug_9801", has - 1)
    setplayvar(p, "pillAt", now)
    setplayvar(p, "pillUsed", used + 1)
    restoreHp(p, 500)
end