from __future__ import annotations

import json
import logging
import time
from pathlib import Path
from typing import Any

from yuxi.channel.extensions.qqbot.types import SessionState

logger = logging.getLogger(__name__)

DEFAULT_SESSION_DIR = Path.home() / ".forcepilot" / "qqbot" / "sessions"
SESSION_EXPIRE_SECONDS = 300


class SessionStore:
    def __init__(self, session_dir: Path | None = None):
        self._session_dir = session_dir or DEFAULT_SESSION_DIR
        self._session_dir.mkdir(parents=True, exist_ok=True)

    def _session_path(self, account_id: str) -> Path:
        safe_id = account_id.replace("/", "_").replace("\\", "_")
        return self._session_dir / f"{safe_id}.json"

    def save(self, account_id: str, state: SessionState) -> None:
        path = self._session_path(account_id)
        data = {
            "session_id": state.session_id,
            "last_seq": state.last_seq,
            "last_connected_at": state.last_connected_at,
            "account_id": state.account_id,
            "saved_at": time.time(),
            "app_id": state.app_id,
        }
        try:
            path.write_text(json.dumps(data, ensure_ascii=False), encoding="utf-8")
            logger.debug("Session saved for account '%s': session_id=%s", account_id, state.session_id)
        except OSError as e:
            logger.warning("Failed to save session for '%s': %s", account_id, e)

    def load(self, account_id: str) -> SessionState | None:
        path = self._session_path(account_id)
        if not path.exists():
            return None
        try:
            data = json.loads(path.read_text(encoding="utf-8"))
            saved_at = data.get("saved_at", 0)
            if time.time() - saved_at > SESSION_EXPIRE_SECONDS:
                logger.debug("Session expired for account '%s'", account_id)
                return None
            return SessionState(
                session_id=data.get("session_id"),
                last_seq=data.get("last_seq"),
                last_connected_at=data.get("last_connected_at", 0),
                account_id=data.get("account_id", account_id),
                saved_at=saved_at,
                app_id=data.get("app_id"),
            )
        except (json.JSONDecodeError, OSError) as e:
            logger.warning("Failed to load session for '%s': %s", account_id, e)
        return None

    def clear(self, account_id: str) -> None:
        path = self._session_path(account_id)
        try:
            path.unlink(missing_ok=True)
        except OSError:
            pass

    def clear_all(self) -> None:
        for path in self._session_dir.glob("*.json"):
            try:
                path.unlink()
            except OSError:
                pass