#!/usr/bin/env python3
"""Enforce per-file coverage thresholds from SlipCover JSON output."""

from __future__ import annotations

import argparse
import json
from datetime import date
from pathlib import Path


def main() -> int:  # noqa: C901
    """Check each production file against a minimum coverage percentage."""

    parser = argparse.ArgumentParser()
    parser.add_argument("coverage_json")
    parser.add_argument("--root", default="atlasbot")
    parser.add_argument("--threshold", type=float, default=95.0)
    parser.add_argument("--exceptions-file", default="testing/coverage_exceptions.json")
    args = parser.parse_args()

    data = json.loads(Path(args.coverage_json).read_text(encoding="utf-8"))
    files = data.get("files") if isinstance(data, dict) else {}
    exceptions_path = Path(args.exceptions_file)
    per_file_thresholds: dict[str, float] = {}
    if exceptions_path.exists():
        payload = json.loads(exceptions_path.read_text(encoding="utf-8"))
        expires_on = str(payload.get("expires_on") or "").strip()
        if expires_on and date.today() > date.fromisoformat(expires_on):
            print(f"coverage exceptions expired on {expires_on}: {exceptions_path}")
            return 1
        overrides = payload.get("per_file_thresholds")
        if isinstance(overrides, dict):
            for path, threshold in overrides.items():
                if isinstance(path, str) and isinstance(threshold, (int, float)):
                    per_file_thresholds[path] = float(threshold)
    violations: list[tuple[float, str]] = []
    for path, payload in sorted(files.items()):
        if not path.startswith(f"{args.root}/"):
            continue
        summary = payload.get("summary") if isinstance(payload, dict) else {}
        percent = summary.get("percent_covered") if isinstance(summary, dict) else None
        if not isinstance(percent, (int, float)):
            continue
        threshold = per_file_thresholds.get(path, float(args.threshold))
        if float(percent) < threshold:
            violations.append((float(percent), f"{path} (min {threshold:.2f}%)"))

    if violations:
        for percent, path in sorted(violations):
            print(f"{path}: {percent:.2f}% < {args.threshold:.2f}%")
        return 1
    return 0


if __name__ == "__main__":
    raise SystemExit(main())