"""CT Hounsfield-unit window/level presets and conversion helpers."""
from __future__ import annotations

from dataclasses import dataclass


@dataclass(frozen=True)
class WLPreset:
    name: str
    width: float
    level: float

    def to_min_max(self) -> tuple[float, float]:
        return self.level - self.width / 2.0, self.level + self.width / 2.0


CT_PRESETS: dict[str, WLPreset] = {
    "soft_tissue": WLPreset("Soft Tissue", 350, 50),
    "lung": WLPreset("Lung", 1500, -600),
    "bone": WLPreset("Bone", 1800, 400),
    "brain": WLPreset("Brain", 80, 40),
}

CT_PRESET_LABELS = [p.name for p in CT_PRESETS.values()]