from services.statistics import get_ammeter_left_ele, get_water_left
from services.plot import plot_line


async def render_ammeter_chart():
    times, values = await get_ammeter_left_ele(limit=24)

    if not times:
        return None

    out = "data/ammeter.png"

    plot_line(
        times=times,
        values=values,
        title="宿舍电量剩余趋势",
        ylabel="剩余电量（度）",
        out_path=out,
    )

    return out


async def render_water_chart():
    times, values = await get_water_left(limit=24)

    if not times:
        return None

    out = "data/water.png"

    plot_line(
        times=times,
        values=values,
        title="宿舍水量剩余趋势",
        ylabel="剩余水量（吨）",
        out_path=out,
    )

    return out