from pathlib import Path
import json

ROOT = Path(__file__).resolve().parents[1]


def _validate_feature_collection(path: Path) -> None:
    data = json.loads(path.read_text(encoding="utf-8"))
    if data.get("type") != "FeatureCollection":
        raise SystemExit(f"{path} is not a FeatureCollection")
    features = data.get("features")
    if not isinstance(features, list):
        raise SystemExit(f"{path} has no feature list")
    for index, feature in enumerate(features):
        geometry = feature.get("geometry") if isinstance(feature, dict) else None
        if not isinstance(geometry, dict) or not geometry.get("type"):
            raise SystemExit(f"{path} feature {index} has no geometry")


def _validate_fixture_dir(relative_path: str) -> None:
    fixture_dir = ROOT / relative_path
    if not fixture_dir.exists():
        raise SystemExit(f"{relative_path} missing")
    for path in fixture_dir.glob("*.geojson"):
        _validate_feature_collection(path)


_validate_fixture_dir("fixtures/geojson")
_validate_fixture_dir("fixtures/golden")

expected_path = ROOT / "fixtures" / "golden" / "expected_qa_metrics.json"
expected = json.loads(expected_path.read_text(encoding="utf-8"))
for key in ("candidate_fixture", "reference_fixture"):
    fixture_path = ROOT / expected[key]
    if not fixture_path.exists():
        raise SystemExit(f"Golden QA fixture missing: {fixture_path}")

print("Fixture validation OK")