local timehud = rawget(_G, "timehud")
if type(timehud) ~= "table" then
    return
end

minetest.register_chatcommand("timerdemo", {
    description = "Start a 30s demo timer",
    func = function(name)
        local timer = timehud.add_timer(name, {
            name = "Demo",
            duration = 30,
            color = "55ff55",
            on_complete = function(player_name, _timer)
                minetest.chat_send_player(player_name, "Demo timer finished.")
            end,
            on_event = {
                boost_tick = function(player_name, t)
                    -- Example: subtract 1s when this event is triggered.
                    t.time_left = math.max(1, (tonumber(t.time_left) or 1) - 1)
                end,
            },
        })

        if not timer then
            return false, "Could not create timer."
        end

        -- Optional immediate refresh.
        timehud.update_timers(name)
        return true, "Demo timer started."
    end,
})

-- Somewhere else in your code:
-- timehud.trigger_event(player_name, "boost_tick")
-- timehud.remove_timer_by_reference(player_name, timer)