"""
System Settings Database Service
"""
from sqlalchemy import select, update, delete
from sqlalchemy.ext.asyncio import AsyncSession
from typing import Optional, List, Dict, Any
import json
import logging

from app.models.db import SystemSettings

logger = logging.getLogger(__name__)


class SystemSettingsService:
    """Service for managing system settings"""

    async def get_all_settings(
        self,
        session: AsyncSession,
        category: Optional[str] = None,
        is_public: Optional[bool] = None
    ) -> List[SystemSettings]:
        """Get all settings, optionally filtered by category or public status"""
        query = select(SystemSettings)

        if category:
            query = query.where(SystemSettings.category == category)
        if is_public is not None:
            query = query.where(SystemSettings.is_public == is_public)

        result = await session.execute(query)
        return result.scalars().all()

    async def get_setting(
        self,
        key: str,
        session: AsyncSession
    ) -> Optional[SystemSettings]:
        """Get a setting by key"""
        result = await session.execute(
            select(SystemSettings).where(SystemSettings.key == key)
        )
        return result.scalar_one_or_none()

    async def get_setting_value(
        self,
        key: str,
        session: AsyncSession,
        default: Any = None
    ) -> Any:
        """Get setting value with type conversion"""
        setting = await self.get_setting(key, session)
        if not setting:
            return default

        # Convert value based on type
        try:
            if setting.value_type == "int":
                return int(setting.value)
            elif setting.value_type == "float":
                return float(setting.value)
            elif setting.value_type == "bool":
                return setting.value.lower() in ("true", "1", "yes")
            elif setting.value_type == "json":
                return json.loads(setting.value)
            else:  # string
                return setting.value
        except Exception as e:
            logger.error(f"Error converting setting {key}: {e}")
            return default

    async def create_setting(
        self,
        data: Dict[str, Any],
        session: AsyncSession
    ) -> SystemSettings:
        """Create a new setting"""
        # Convert value to string for storage
        value = data.get("value")
        value_type = data.get("value_type", "string")

        if value_type == "json" and not isinstance(value, str):
            value = json.dumps(value)
        else:
            value = str(value)

        new_setting = SystemSettings(
            key=data["key"],
            value=value,
            value_type=value_type,
            category=data.get("category", "general"),
            label=data["label"],
            description=data.get("description"),
            is_public=data.get("is_public", False)
        )

        session.add(new_setting)
        await session.flush()
        await session.refresh(new_setting)
        return new_setting

    async def update_setting(
        self,
        key: str,
        data: Dict[str, Any],
        session: AsyncSession
    ) -> Optional[SystemSettings]:
        """Update a setting"""
        setting = await self.get_setting(key, session)
        if not setting:
            return None

        # Convert value to string if needed
        if "value" in data:
            value = data["value"]
            value_type = data.get("value_type", setting.value_type)

            if value_type == "json" and not isinstance(value, str):
                data["value"] = json.dumps(value)
            else:
                data["value"] = str(value)

        for key, value in data.items():
            if hasattr(setting, key) and value is not None:
                setattr(setting, key, value)

        await session.flush()
        await session.refresh(setting)
        return setting

    async def delete_setting(
        self,
        key: str,
        session: AsyncSession
    ) -> bool:
        """Delete a setting"""
        result = await session.execute(
            delete(SystemSettings).where(SystemSettings.key == key)
        )
        return result.rowcount > 0

    async def initialize_default_settings(self, session: AsyncSession):
        """Initialize default system settings if they don't exist"""
        defaults = [
            {
                "key": "default_password",
                "value": "cosmo",
                "value_type": "string",
                "category": "security",
                "label": "默认重置密码",
                "description": "管理员重置用户密码时使用的默认密码",
                "is_public": False
            },
            {
                "key": "timeline_interval_days",
                "value": "30",
                "value_type": "int",
                "category": "visualization",
                "label": "时间轴播放间隔（天）",
                "description": "星图时间轴播放时每次跳转的天数间隔",
                "is_public": True
            },
            {
                "key": "current_cache_ttl_hours",
                "value": "1",
                "value_type": "int",
                "category": "cache",
                "label": "当前位置缓存时间（小时）",
                "description": "当前位置数据在缓存中保存的时间",
                "is_public": False
            },
            {
                "key": "historical_cache_ttl_days",
                "value": "7",
                "value_type": "int",
                "category": "cache",
                "label": "历史位置缓存时间（天）",
                "description": "历史位置数据在缓存中保存的时间",
                "is_public": False
            },
            {
                "key": "page_size",
                "value": "10",
                "value_type": "int",
                "category": "ui",
                "label": "每页显示数量",
                "description": "管理页面默认每页显示的条数",
                "is_public": True
            },
            {
                "key": "nasa_api_timeout",
                "value": "30",
                "value_type": "int",
                "category": "api",
                "label": "NASA API超时时间（秒）",
                "description": "查询NASA Horizons API的超时时间",
                "is_public": False
            },
            {
                "key": "orbit_points",
                "value": "200",
                "value_type": "int",
                "category": "visualization",
                "label": "轨道线点数",
                "description": "生成轨道线时使用的点数，越多越平滑但性能越低",
                "is_public": True
            },
        ]

        for default in defaults:
            existing = await self.get_setting(default["key"], session)
            if not existing:
                await self.create_setting(default, session)
                logger.info(f"Created default setting: {default['key']}")


# Singleton instance
system_settings_service = SystemSettingsService()