"""Fixture discovery and materialization helpers for release fixtures.

Each fixture is a directory under ``tests/fixtures/releases/<bucket>/<case>/``
containing one ``expected.yaml`` file. See ``releases/README.md`` for the
schema.
"""

from __future__ import annotations

from dataclasses import dataclass
from pathlib import Path

import yaml

FIXTURES_ROOT = Path(__file__).parent


@dataclass(frozen=True)
class ReleaseFixture:
    """A loaded fixture, ready to be materialized into a temp dir."""

    name: str  # "<bucket>/<case>", e.g. "easy/back_in_action"
    path: Path  # directory containing expected.yaml
    data: dict  # parsed YAML contents

    @property
    def release_name(self) -> str:
        return self.data["release_name"]

    @property
    def expected_parsed(self) -> dict:
        return self.data.get("parsed", {})

    @property
    def tree(self) -> list[str]:
        return self.data.get("tree", [])

    @property
    def routing(self) -> dict:
        return self.data.get("routing", {})

    @property
    def xfail_reason(self) -> str | None:
        """If set, the fixture is expected to fail — wrapped with
        ``pytest.mark.xfail`` by the test runner. Used for known
        not-supported pathological cases (typically PATH OF PAIN bucket).
        """
        return self.data.get("xfail_reason")

    def materialize(self, root: Path) -> None:
        """Create the fixture's ``tree`` as empty files/dirs under ``root``."""
        for entry in self.tree:
            target = root / entry
            if entry.endswith("/"):
                target.mkdir(parents=True, exist_ok=True)
            else:
                target.parent.mkdir(parents=True, exist_ok=True)
                target.touch()


def discover_fixtures() -> list[ReleaseFixture]:
    """Find all ``expected.yaml`` files under FIXTURES_ROOT."""
    fixtures = []
    for yaml_path in sorted(FIXTURES_ROOT.glob("*/*/expected.yaml")):
        data = yaml.safe_load(yaml_path.read_text())
        name = f"{yaml_path.parent.parent.name}/{yaml_path.parent.name}"
        fixtures.append(ReleaseFixture(name=name, path=yaml_path.parent, data=data))
    return fixtures