import importlib.util
import sys
from pathlib import Path

import pytest

REPO_ROOT = Path(__file__).resolve().parent.parent
sys.path.insert(0, str(REPO_ROOT))


def _load_pipeline(name: str):
    """Import a pipeline's publish.py under a unique module name.

    The three pipelines each define a module called `publish`, so they cannot be
    imported by plain name without colliding in sys.modules.
    """
    spec = importlib.util.spec_from_file_location(
        f"{name}_publish", REPO_ROOT / "pipelines" / name / "publish.py"
    )
    module = importlib.util.module_from_spec(spec)
    sys.modules[spec.name] = module
    spec.loader.exec_module(module)
    return module


@pytest.fixture(scope="session")
def songs():
    return _load_pipeline("songs")


@pytest.fixture
def repo(tmp_path):
    """Build a source tree of .md files: write(relative_path, frontmatter, body)."""

    def write(rel: str, front: str = "", body: str = "") -> Path:
        path = tmp_path / rel
        path.parent.mkdir(parents=True, exist_ok=True)
        path.write_text(f"---\n{front}\n---\n\n{body}\n", encoding="utf-8")
        return path

    write.root = tmp_path
    return write