DOMAIN = "easee_solar_charging"

CONF_CHARGER_ID = "charger_id"
CONF_DEVICE_ID = "device_id"
CONF_SITE_ID = "site_id"
CONF_SOLAR_PRODUCTION_SENSOR = "solar_production_sensor"
CONF_HOUSE_LOAD_SENSOR = "house_load_sensor"
CONF_EV_CHARGING_SENSOR = "ev_charging_sensor"

ROLLING_AVERAGE_SECONDS = 30

EASEE_DOMAIN = "easee"
EASEE_SERVICE_SET_DYNAMIC_LIMIT = "set_charger_dynamic_limit"
EASEE_CONTROLLABLE_STATES = {"awaiting_start", "ready_to_charge", "charging"}
# States where the session is finished/sleeping: set current to 0 once, then idle.
EASEE_SLEEPING_STATES = {"completed", "awaiting_authorization", "awaiting_schedule"}

DEFAULT_SCAN_INTERVAL = 30  # seconds

# Charging current constraints
VOLTAGE_V = 230
PHASES = 3
MIN_CHARGER_CURRENT_A = 6
MAX_CHARGER_CURRENT_A = 16

# Hysteresis
HYSTERESIS_A = 2  # dead-band within the charging range (fixed)

CONF_STOP_GRACE_MINUTES = "stop_grace_minutes"
DEFAULT_STOP_GRACE_MINUTES = 5

CONF_CHARGING_PROFILE = "charging_profile"
CHARGING_PROFILE_CONSERVATIVE = "conservative"
CHARGING_PROFILE_ALL_SURPLUS = "all_surplus"
DEFAULT_CHARGING_PROFILE = CHARGING_PROFILE_CONSERVATIVE

CONF_DEAD_BAND_RESYNC_MINUTES = "dead_band_resync_minutes"
DEFAULT_DEAD_BAND_RESYNC_MINUTES = 1

CONF_NOTIFY_TARGET = "notify_target"

# Watts available at each valid current step on a 3-phase 230V system (P = 3 × V × I)
AMPS_TO_POWER_W: dict[int, int] = {
    a: PHASES * VOLTAGE_V * a
    for a in range(MIN_CHARGER_CURRENT_A, MAX_CHARGER_CURRENT_A + 1)
}


def solar_excess_to_charger_current(excess_w: float) -> int:
    """Return the highest valid charger current (A) that fits within excess_w.

    Returns 0 if excess is below the minimum charging threshold (6 A).
    Steps are 1 A increments between 6 A and 16 A on a 3-phase 230 V system.
    """
    amps = int(excess_w / (PHASES * VOLTAGE_V))
    if amps < MIN_CHARGER_CURRENT_A:
        return 0
    return min(amps, MAX_CHARGER_CURRENT_A)