from dashboard_data.card_utils import safe_number


def build_water_need_prediction(sensor_id: str, context: dict | None = None, ai_bundle: dict | None = None) -> dict:
    forecasts = (context or {}).get("forecasts", [])
    daily_needs = []
    for forecast in forecasts[:7]:
        et0 = safe_number(forecast.et0, 4)
        rain = safe_number(forecast.precipitation, 0)
        need = max(0, round((et0 * 100) - (rain * 20)))
        daily_needs.append(need)

    return {
        "totalNext7Days": sum(daily_needs),
        "unit": "m³",
        "categories": [f"روز {index}" for index in range(1, len(daily_needs) + 1)],
        "series": [{"name": "نیاز آبی", "data": daily_needs}],
    }