"""Shared mapping for the sar3d bottom-view projection choices.

The bottom plot of the sar3d mode projects the imaged volume along a
horizontal direction rotated around the vertical Y axis: 0° = front view
(X horizontal), 90° = side view (Z horizontal). One shared mapping keeps the
combo box, the live-config build, the profile persistence and the plot labels
consistent.
"""

from __future__ import annotations

SAR3D_BOTTOM_VIEW_CHOICES: tuple[tuple[str, float], ...] = (
    ("front (0°)", 0.0),
    ("30°", 30.0),
    ("60°", 60.0),
    ("side (90°)", 90.0),
)


def sar3d_bottom_view_deg_from_label(label: str) -> float:
    """Map a bottom-view combo label to its projection angle in degrees."""
    for choice_label, degrees in SAR3D_BOTTOM_VIEW_CHOICES:
        if choice_label == label:
            return degrees
    return 0.0


def sar3d_bottom_view_label_from_deg(degrees: float) -> str:
    """Map a projection angle to the nearest bottom-view combo label."""
    return min(SAR3D_BOTTOM_VIEW_CHOICES, key=lambda choice: abs(choice[1] - float(degrees)))[0]