"""Release notes generation — three-tier strategy."""

from __future__ import annotations

from github.Repository import Repository

from .github_client import GHClient


def build_notes(
    version: str,
    hf_repo: str | None,
    gh_client: GHClient | None,
    gh_repo_obj: Repository | None,
    previous_tag: str | None = None,
    notes_file: str | None = None,
) -> str:
    # Tier 0: explicit file override
    if notes_file:
        try:
            with open(notes_file) as f:
                return f.read()
        except OSError:
            pass

    # Tier 1: GitHub native generation
    if gh_client and gh_repo_obj:
        notes = gh_client.generate_notes(gh_repo_obj, version, previous_tag)
        if notes:
            return _append_ml_artifacts(notes, version, hf_repo, gh_repo_obj.full_name)

    # Tier 3: minimal fallback
    parts = [f"Release {version}"]
    if hf_repo:
        parts.append(f"\n\n**Hugging Face Hub:** https://huggingface.co/{hf_repo}")
    if gh_repo_obj:
        parts.append(f"\n**GitHub:** https://github.com/{gh_repo_obj.full_name}/releases/tag/{version}")
    return "".join(parts)


def _append_ml_artifacts(body: str, version: str, hf_repo: str | None, gh_repo: str) -> str:
    rows = []
    if hf_repo:
        rows.append(
            f"| Hugging Face Hub | [Model files](https://huggingface.co/{hf_repo}/tree/{version}) |"
        )
        rows.append(
            f"| Model Card | [README](https://huggingface.co/{hf_repo}) |"
        )
    rows.append(
        f"| GitHub | [Release](https://github.com/{gh_repo}/releases/tag/{version}) |"
    )

    section = (
        "\n\n## ML Artifacts\n\n"
        "| Platform | Link |\n"
        "|----------|------|\n"
        + "\n".join(rows)
    )
    return body + section