import math


def as_float(value, default=0.0):
    try:
        if value is None:
            return default
        return float(value)
    except Exception:
        return default


def roof_kwp(roof):
    return as_float(roof.get("kwp", roof.get("leistung", roof.get("pv_kwp", 0.0))), 0.0)


def roof_azimuth_deg(roof):
    return as_float(roof.get("azimut", roof.get("azimuth", roof.get("ausrichtung", 180.0))), 180.0)


def roof_tilt_deg(roof):
    return as_float(roof.get("neigung", roof.get("tilt", 30.0)), 30.0)


def roof_features(config):
    roofs = config.get("daecher", []) or []
    if not roofs:
        roofs = [{"kwp": as_float(config.get("ac_leistung", 0.0), 0.0), "azimut": 180.0, "neigung": 30.0}]
    total_kwp = sum(roof_kwp(r) for r in roofs)
    if total_kwp <= 0:
        total_kwp = as_float(config.get("ac_leistung", 0.0), 0.0)
    weighted_az = 0.0
    weighted_tilt = 0.0
    south_factor = 0.0
    for roof in roofs:
        w = roof_kwp(roof) / total_kwp if total_kwp > 0 else 0.0
        az = roof_azimuth_deg(roof)
        tilt = roof_tilt_deg(roof)
        weighted_az += w * az
        weighted_tilt += w * tilt
        south_factor += w * max(0.0, math.cos(math.radians(az - 180.0)))
    return {
        "pv_kwp_total": total_kwp,
        "roof_azimuth_sin": math.sin(math.radians(weighted_az)),
        "roof_azimuth_cos": math.cos(math.radians(weighted_az)),
        "roof_tilt_avg": weighted_tilt,
        "roof_south_factor": south_factor,
    }


def calc_pure_math_pv(config, dt):
    ac_limit = as_float(config.get("ac_leistung", 10.0), 10.0) * 1000.0
    roofs = config.get("daecher", []) or []
    if not roofs:
        roofs = [{"kwp": as_float(config.get("ac_leistung", 0.0), 0.0), "neigung": 30.0, "azimut": 180.0}]

    day = dt.timetuple().tm_yday
    hour = dt.hour + dt.minute / 60.0
    lat = math.radians(as_float(config.get("latitude", 47.0), 47.0))
    decl = math.radians(23.45 * math.sin(math.radians(360.0 * (day - 81) / 365.0)))
    hour_angle = math.radians(15.0 * (hour - 12.0))

    sin_alt = math.sin(lat) * math.sin(decl) + math.cos(lat) * math.cos(decl) * math.cos(hour_angle)
    sun_alt = math.asin(max(-1.0, min(1.0, sin_alt)))
    if sun_alt <= 0.0:
        return 0.0

    sun_az = math.atan2(
        math.sin(hour_angle),
        math.cos(hour_angle) * math.sin(lat) - math.tan(decl) * math.cos(lat),
    )

    total = 0.0
    for roof in roofs:
        kwp = roof_kwp(roof)
        if kwp <= 0:
            continue
        tilt = math.radians(roof_tilt_deg(roof))
        az = math.radians(roof_azimuth_deg(roof))
        cos_inc = math.sin(sun_alt) * math.cos(tilt) + math.cos(sun_alt) * math.sin(tilt) * math.cos(sun_az - az)
        if cos_inc > 0:
            total += kwp * 1000.0 * cos_inc

    return max(0.0, min(total, ac_limit))


def calc_pure_math_load(dt):
    hour = dt.hour + dt.minute / 60.0
    base = 650.0
    morning = 220.0 * math.exp(-((hour - 7.0) ** 2) / 5.0)
    evening = 380.0 * math.exp(-((hour - 19.0) ** 2) / 8.0)
    weekend = 1.12 if dt.weekday() >= 5 else 1.0
    return max(0.0, (base + morning + evening) * weekend)