from datetime import datetime, timedelta, timezone

from app.db.database import get_connection
from app.db.migrations import run_migrations


def parse_timestamp(value: str | None) -> datetime | None:
    if not value:
        return None

    normalized = value.strip().replace("Z", "+00:00")
    formats = [
        "%Y-%m-%d %H:%M:%S",
        "%Y-%m-%d %H:%M:%S.%f",
        "%Y-%m-%dT%H:%M:%S",
        "%Y-%m-%dT%H:%M:%S.%f",
    ]

    try:
        parsed = datetime.fromisoformat(normalized)
        return parsed.astimezone(timezone.utc).replace(tzinfo=None) if parsed.tzinfo else parsed
    except ValueError:
        pass

    for fmt in formats:
        try:
            return datetime.strptime(normalized, fmt)
        except ValueError:
            continue

    return None


def is_worker_online(last_seen_at: str | None) -> bool:
    last_seen = parse_timestamp(last_seen_at)
    if not last_seen:
        return False

    return last_seen >= datetime.utcnow() - timedelta(seconds=30)


def with_online_status(worker: dict):
    worker["online"] = is_worker_online(worker.get("last_seen_at"))
    return worker


def get_workers():
    run_migrations()
    con = get_connection()

    rows = con.execute(
        """
        SELECT
            id,
            status,
            started_at,
            last_seen_at,
            current_job_id,
            metadata_json
        FROM workers
        ORDER BY id
        """
    ).fetchall()

    con.close()
    return [with_online_status(dict(row)) for row in rows]


def get_worker(worker_id: str):
    run_migrations()
    con = get_connection()

    row = con.execute(
        """
        SELECT
            id,
            status,
            started_at,
            last_seen_at,
            current_job_id,
            metadata_json
        FROM workers
        WHERE id = ?
        """,
        (worker_id,),
    ).fetchone()

    con.close()
    return with_online_status(dict(row)) if row else None