"""challenges.yml: which repos are part of this CTF, and their check exceptions."""
from __future__ import annotations

from dataclasses import dataclass
from pathlib import Path

import yaml

from .challenge import SELECTIONS
from .checks import REPO_CHECKS

SELECTION_FILE = Path(__file__).parent.parent / "challenges.yml"  # next to ctf_status.py


@dataclass
class Selection:
    states: dict       # repo path -> one of SELECTIONS
    skip_checks: dict  # repo path -> names of REPO_CHECKS it need not pass


def load_selection(path: Path = SELECTION_FILE) -> Selection:
    """Raises ValueError on anything off. A broken file must stop the run: without
    it nothing counts as included, and challs.txt would be committed empty."""
    try:
        doc = yaml.safe_load(path.read_text())
    except (OSError, yaml.YAMLError) as e:
        raise ValueError(f"cannot read {path.name}: {e}") from None
    states = doc.get("challenges") if isinstance(doc, dict) else None
    if not states or not isinstance(states, dict):
        raise ValueError(f"{path.name} has no `challenges:` mapping")
    bad = [f"{k}: {v}" for k, v in states.items() if v not in SELECTIONS]
    if bad:
        raise ValueError(f"{path.name}: expected one of {', '.join(SELECTIONS)}, got " + ", ".join(bad))

    skip = doc.get("skip_checks") or {}
    if not isinstance(skip, dict) or not all(isinstance(v, list) for v in skip.values()):
        raise ValueError(f"{path.name}: `skip_checks:` must map repos to lists of checks")
    known = {check.__name__ for check in REPO_CHECKS}
    bad = sorted({str(n) for names in skip.values() for n in names} - known)
    if bad:
        raise ValueError(f"{path.name}: no such repo check: " + ", ".join(bad))
    return Selection({str(k): v for k, v in states.items()},
                     {str(k): [str(n) for n in v] for k, v in skip.items()})