"""Create safe runtime backups for the AtoCore machine store."""

from __future__ import annotations

import json
import sqlite3
from datetime import datetime, UTC
from pathlib import Path

import atocore.config as _config
from atocore.models.database import init_db
from atocore.observability.logger import get_logger

log = get_logger("backup")


def create_runtime_backup(timestamp: datetime | None = None) -> dict:
    """Create a hot backup of the SQLite DB plus registry/config metadata."""
    init_db()
    now = timestamp or datetime.now(UTC)
    stamp = now.strftime("%Y%m%dT%H%M%SZ")

    backup_root = _config.settings.resolved_backup_dir / "snapshots" / stamp
    db_backup_dir = backup_root / "db"
    config_backup_dir = backup_root / "config"
    metadata_path = backup_root / "backup-metadata.json"

    db_backup_dir.mkdir(parents=True, exist_ok=True)
    config_backup_dir.mkdir(parents=True, exist_ok=True)

    db_snapshot_path = db_backup_dir / _config.settings.db_path.name
    _backup_sqlite_db(_config.settings.db_path, db_snapshot_path)

    registry_snapshot = None
    registry_path = _config.settings.resolved_project_registry_path
    if registry_path.exists():
        registry_snapshot = config_backup_dir / registry_path.name
        registry_snapshot.write_text(registry_path.read_text(encoding="utf-8"), encoding="utf-8")

    metadata = {
        "created_at": now.isoformat(),
        "backup_root": str(backup_root),
        "db_snapshot_path": str(db_snapshot_path),
        "db_size_bytes": db_snapshot_path.stat().st_size,
        "registry_snapshot_path": str(registry_snapshot) if registry_snapshot else "",
        "vector_store_note": "Chroma hot backup is not included in this script; use a cold snapshot or rebuild/export workflow.",
    }
    metadata_path.write_text(json.dumps(metadata, indent=2, ensure_ascii=True) + "\n", encoding="utf-8")

    log.info("runtime_backup_created", backup_root=str(backup_root), db_snapshot=str(db_snapshot_path))
    return metadata


def _backup_sqlite_db(source_path: Path, dest_path: Path) -> None:
    source_conn = sqlite3.connect(str(source_path))
    dest_conn = sqlite3.connect(str(dest_path))
    try:
        source_conn.backup(dest_conn)
    finally:
        dest_conn.close()
        source_conn.close()


def main() -> None:
    result = create_runtime_backup()
    print(json.dumps(result, indent=2, ensure_ascii=True))


if __name__ == "__main__":
    main()