"""Pure Phase 4 yaw and turn-level rules."""

from .config_loader import TurnDetectionSettings
from .models import TurnLevel


LEVEL_ORDER = {
    TurnLevel.NONE.value: 0,
    TurnLevel.FACE_APPEARED.value: 0,
    TurnLevel.SUBTLE.value: 1,
    TurnLevel.WEAK.value: 2,
    TurnLevel.MEDIUM.value: 3,
    TurnLevel.STRONG.value: 4,
    TurnLevel.NOT_EVALUABLE.value: -1,
}


def yaw_delta_toward_signage(current_yaw: float, baseline_yaw: float, direction: str) -> tuple[float, float]:
    """Return raw delta and a delta whose positive sign points toward signage."""
    if direction not in {"positive", "negative"}:
        raise ValueError("direction must be positive or negative")
    raw = current_yaw - baseline_yaw
    return raw, raw if direction == "positive" else -raw


def classify_turn_level(delta: float, config: TurnDetectionSettings) -> str:
    if delta < config.subtle_threshold_deg:
        return TurnLevel.NONE.value
    if delta < config.weak_threshold_deg:
        return TurnLevel.SUBTLE.value
    if delta < config.medium_threshold_deg:
        return TurnLevel.WEAK.value
    if delta < config.strong_threshold_deg:
        return TurnLevel.MEDIUM.value
    return TurnLevel.STRONG.value


def is_weak_or_higher(level: str) -> bool:
    return LEVEL_ORDER.get(level, -1) >= LEVEL_ORDER[TurnLevel.WEAK.value]


def stronger_level(first: str, second: str) -> str:
    return second if LEVEL_ORDER.get(second, -1) > LEVEL_ORDER.get(first, -1) else first