"""Tests for model registry (src/model_registry.py)."""

import pytest
from src.model_registry import (
    scan_models,
    scan_model_groups,
    ModelConfig,
    ModelGroup,
    _sort_formats,
    FORMAT_PREFERENCE,
)


def test_scan_returns_list():
    result = scan_models("/nonexistent/path")
    assert isinstance(result, list)


def test_scan_empty_dir(tmp_path):
    result = scan_models(str(tmp_path))
    assert result == []


def test_scan_finds_pt_files(tmp_path):
    (tmp_path / "best.pt").write_bytes(b"fake")
    (tmp_path / "truck-detector.pt").write_bytes(b"fake")
    result = scan_models(str(tmp_path))
    assert len(result) == 2
    names = {m.filename for m in result}
    assert "best.pt" in names
    assert "truck-detector.pt" in names


def test_scan_skips_non_model_files(tmp_path):
    (tmp_path / "modelREADME.md").write_text("readme")
    (tmp_path / "best.pt").write_bytes(b"fake")
    result = scan_models(str(tmp_path))
    assert len(result) == 1


def test_model_config_fields(tmp_path):
    (tmp_path / "v4-best.pt").write_bytes(b"fake")
    result = scan_models(str(tmp_path))
    cfg = result[0]
    assert cfg.filename == "v4-best.pt"
    assert cfg.path == str(tmp_path / "v4-best.pt")
    assert isinstance(cfg.known_classes, list)


def test_model_config_fallback_classes(tmp_path):
    (tmp_path / "unknown-model.pt").write_bytes(b"fake")
    result = scan_models(str(tmp_path))
    cfg = result[0]
    assert cfg.known_classes == []


# --- scan_model_groups tests ---


def test_scan_model_groups_returns_list():
    result = scan_model_groups("/nonexistent/path")
    assert isinstance(result, list)


def test_scan_model_groups_empty_dir(tmp_path):
    result = scan_model_groups(str(tmp_path))
    assert result == []


def test_scan_model_groups_single_stem(tmp_path):
    (tmp_path / "best.pt").write_bytes(b"fake")
    (tmp_path / "best.onnx").write_bytes(b"fake")
    (tmp_path / "best.engine").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    assert len(result) == 1
    g = result[0]
    assert g.stem == "best"
    assert ".engine" in g.formats
    assert ".pt" in g.formats
    assert ".onnx" in g.formats
    assert g.default_format == ".engine"


def test_scan_model_groups_format_preference(tmp_path):
    (tmp_path / "model.pt").write_bytes(b"fake")
    (tmp_path / "model.onnx").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    g = result[0]
    assert g.formats == [".pt", ".onnx"]
    assert g.default_format == ".pt"


def test_scan_model_groups_sorted_by_stem(tmp_path):
    (tmp_path / "z-model.pt").write_bytes(b"fake")
    (tmp_path / "a-model.pt").write_bytes(b"fake")
    (tmp_path / "m-model.pt").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    stems = [g.stem for g in result]
    assert stems == sorted(stems)


def test_scan_model_groups_known_classes(tmp_path):
    (tmp_path / "truck-detector.pt").write_bytes(b"fake")
    (tmp_path / "truck-detector.onnx").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    g = result[0]
    assert g.known_classes == ["truck"]


def test_scan_model_groups_unknown_stem(tmp_path):
    (tmp_path / "unknown-model.pt").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    g = result[0]
    assert g.known_classes == []


def test_scan_model_groups_format_paths(tmp_path):
    (tmp_path / "best.pt").write_bytes(b"fake")
    (tmp_path / "best.engine").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    g = result[0]
    assert ".pt" in g.format_paths
    assert ".engine" in g.format_paths
    assert g.format_paths[".pt"] == str((tmp_path / "best.pt").resolve())
    assert g.format_paths[".engine"] == str((tmp_path / "best.engine").resolve())


def test_scan_model_groups_skips_non_model_files(tmp_path):
    (tmp_path / "best.pt").write_bytes(b"fake")
    (tmp_path / "readme.md").write_text("hi")
    result = scan_model_groups(str(tmp_path))
    assert len(result) == 1
    assert result[0].stem == "best"


def test_scan_model_groups_multiple_stems(tmp_path):
    (tmp_path / "best.pt").write_bytes(b"fake")
    (tmp_path / "v4-best.engine").write_bytes(b"fake")
    (tmp_path / "truck-detector.onnx").write_bytes(b"fake")
    result = scan_model_groups(str(tmp_path))
    assert len(result) == 3
    stems = [g.stem for g in result]
    assert "best" in stems
    assert "v4-best" in stems
    assert "truck-detector" in stems


def test_sort_formats_explicit():
    result = _sort_formats([".onnx", ".pt", ".engine"])
    assert result == [".engine", ".pt", ".onnx"]


def test_sort_formats_unknown_ext():
    result = _sort_formats([".pt", ".xyz", ".onnx"])
    assert result == [".pt", ".onnx", ".xyz"]