"""读取/写入键值设置。"""
from __future__ import annotations

import json
from typing import Any, Optional

from sqlalchemy.orm import Session

from app.models.setting import Setting


def get_setting(session: Session, key: str, default: Any = None) -> Any:
    """读取并 JSON 解析。"""
    row = session.get(Setting, key)
    if row is None:
        return default
    try:
        return json.loads(row.value_json)
    except json.JSONDecodeError:
        return default


def set_setting(session: Session, key: str, value: Any) -> None:
    """JSON 序列化后落库（upsert）。"""
    row = session.get(Setting, key)
    payload = json.dumps(value, ensure_ascii=False)
    if row is None:
        session.add(Setting(key=key, value_json=payload))
    else:
        row.value_json = payload
    session.flush()


def all_settings(session: Session) -> dict[str, Any]:
    """返回所有设置，给前端调试 / 导出。"""
    items: dict[str, Any] = {}
    for row in session.query(Setting).all():
        try:
            items[row.key] = json.loads(row.value_json)
        except json.JSONDecodeError:
            items[row.key] = row.value_json
    return items


def get_provider_config(session: Session, key: str) -> Optional[dict[str, Any]]:
    """便捷读取 OCR/VLM provider 配置 dict。"""
    value = get_setting(session, key, None)
    if isinstance(value, dict):
        return value
    return None