"""
Shoulder Mobility rubric scorer — pure function, no model calls.

FMS Shoulder Mobility Criteria (bilateral):
- Score 3: fists within one hand-length of each other.
- Score 2: fists within 1.5 hand-lengths.
- Score 1: fists more than 1.5 hand-lengths apart.
- Score 0: PAIN (clearing test) — never auto-scored.
"""
from __future__ import annotations

from formscout.types import BiomechFeatures, ScoreResult


def score_shoulder_mobility(features: BiomechFeatures) -> ScoreResult:
    """Pure rubric scorer for shoulder mobility."""
    alignments = features.alignments
    angles = features.angles

    has_measure = "inter_fist_normalized" in angles
    if not has_measure:
        return ScoreResult(
            score=1, rationale="Insufficient data: inter-fist distance not measurable",
            confidence=0.3, notes="missing key measurements",
        )

    norm_dist = angles["inter_fist_normalized"]
    within_one = alignments.get("fists_within_one_hand", False)
    within_1_5 = alignments.get("fists_within_1_5_hand", False)

    if within_one:
        score = 3
        rationale = f"Fists within one hand-length (normalized distance {norm_dist:.2f})"
    elif within_1_5:
        score = 2
        rationale = f"Fists within 1.5 hand-lengths (normalized distance {norm_dist:.2f})"
    else:
        score = 1
        rationale = f"Fists beyond 1.5 hand-lengths apart (normalized distance {norm_dist:.2f})"

    confidence = features.confidence * 0.9

    return ScoreResult(
        score=score, rationale=rationale,
        confidence=confidence, notes="",
    )