"""Tests for the Variant contract (harness/genome.py) — LOCKED."""

import json
from pathlib import Path

import pytest

from harness.genome import VariantManifest, VideoArtifact, MANIFEST_FILENAME, parse_artifacts

REPO_ROOT = Path(__file__).resolve().parent.parent


def _write_manifest(tmp_path: Path, data: dict) -> Path:
    (tmp_path / MANIFEST_FILENAME).write_text(json.dumps(data), encoding="utf-8")
    return tmp_path


def test_manifest_load_roundtrip(tmp_path):
    d = _write_manifest(tmp_path, {"variant_id": "v9", "parent": "v1", "genome": {"a": 1}})
    m = VariantManifest.load(d)
    assert m.variant_id == "v9"
    assert m.parent == "v1"
    assert m.genome == {"a": 1}


def test_manifest_defaults_id_to_dirname(tmp_path):
    d = _write_manifest(tmp_path, {"genome": {}})
    m = VariantManifest.load(d)
    assert m.variant_id == tmp_path.name
    assert m.parent == "seed"  # default


def test_genome_hash_is_stable_and_short():
    a = VariantManifest(variant_id="x", genome={"b": 2, "a": 1})
    b = VariantManifest(variant_id="y", genome={"a": 1, "b": 2})  # key order differs
    assert a.genome_hash == b.genome_hash  # canonical (sorted) hashing
    assert len(a.genome_hash) == 12
    assert int(a.genome_hash, 16) >= 0  # valid hex


def test_genome_hash_changes_with_content():
    a = VariantManifest(variant_id="x", genome={"a": 1})
    b = VariantManifest(variant_id="x", genome={"a": 2})
    assert a.genome_hash != b.genome_hash


def test_manifest_rejects_non_object(tmp_path):
    (tmp_path / MANIFEST_FILENAME).write_text("[]", encoding="utf-8")
    with pytest.raises(ValueError):
        VariantManifest.load(tmp_path)


def test_video_artifact_shape():
    a = VideoArtifact(video_path="/tmp/x.mp4", title="t", description="d",
                      music_name="m", music_attribution="attr")
    assert a.video_path == "/tmp/x.mp4" and a.extra == {}


def test_parse_artifacts_resolves_and_drops_missing(tmp_path):
    real = tmp_path / "v1.mp4"
    real.write_bytes(b"\x00\x01")
    (tmp_path / "artifacts.json").write_text(json.dumps({
        "videos": [
            {"video_path": "v1.mp4", "title": "ok"},          # relative, exists → kept
            {"video_path": "missing.mp4", "title": "nope"},    # missing file → dropped
            {"title": "no path"},                              # no path → dropped
        ],
        "errors": [],
    }), encoding="utf-8")
    arts = parse_artifacts(tmp_path)
    assert len(arts) == 1
    assert arts[0].title == "ok"
    assert arts[0].video_path == str(real)


def test_real_variant_1_manifest_loads():
    m = VariantManifest.load(REPO_ROOT / "variants" / "variant_1")
    assert m.variant_id == "variant_1"
    assert "source_description" in m.genome