"""
告警服务
"""
import logging
from datetime import datetime
from typing import List, Optional

from sqlalchemy.orm import Session

from app.models import Alert
from app.db.init_db import SQLiteSessionLocal

logger = logging.getLogger(__name__)


class AlertService:
    """告警服务"""
    
    @staticmethod
    def create_alert(
        user_id: int,
        symbol: str,
        condition_type: str,
        condition_value: float,
        alert_type: str = "price"
    ) -> Alert:
        """创建告警"""
        with SQLiteSessionLocal() as db:
            alert = Alert(
                user_id=user_id,
                symbol=symbol,
                condition_type=condition_type,
                condition_value=condition_value,
                alert_type=alert_type,
                status="active"
            )
            db.add(alert)
            db.commit()
            db.refresh(alert)
            return alert
    
    @staticmethod
    def get_user_alerts(user_id: int, status: Optional[str] = None) -> List[Alert]:
        """获取用户告警列表"""
        with SQLiteSessionLocal() as db:
            query = db.query(Alert).filter(Alert.user_id == user_id)
            if status:
                query = query.filter(Alert.status == status)
            return query.order_by(Alert.created_at.desc()).all()
    
    @staticmethod
    def get_alert_by_id(alert_id: int, user_id: int) -> Optional[Alert]:
        """根据 ID 获取告警"""
        with SQLiteSessionLocal() as db:
            return db.query(Alert).filter(
                Alert.id == alert_id,
                Alert.user_id == user_id
            ).first()
    
    @staticmethod
    def update_alert(
        alert_id: int,
        user_id: int,
        condition_value: Optional[float] = None,
        status: Optional[str] = None
    ) -> Optional[Alert]:
        """更新告警"""
        with SQLiteSessionLocal() as db:
            alert = db.query(Alert).filter(
                Alert.id == alert_id,
                Alert.user_id == user_id
            ).first()
            
            if not alert:
                return None
            
            if condition_value is not None:
                alert.condition_value = condition_value
            if status is not None:
                alert.status = status
                if status == "active" and alert.triggered_at:
                    alert.triggered_at = None
            
            alert.updated_at = datetime.utcnow()
            db.commit()
            db.refresh(alert)
            return alert
    
    @staticmethod
    def delete_alert(alert_id: int, user_id: int) -> bool:
        """删除告警"""
        with SQLiteSessionLocal() as db:
            alert = db.query(Alert).filter(
                Alert.id == alert_id,
                Alert.user_id == user_id
            ).first()
            
            if not alert:
                return False
            
            db.delete(alert)
            db.commit()
            return True
    
    @staticmethod
    def trigger_alert(alert_id: int) -> Optional[Alert]:
        """触发告警"""
        with SQLiteSessionLocal() as db:
            alert = db.query(Alert).filter(Alert.id == alert_id).first()
            if not alert:
                return None
            
            alert.status = "triggered"
            alert.triggered_at = datetime.utcnow()
            alert.updated_at = datetime.utcnow()
            db.commit()
            db.refresh(alert)
            return alert
    
    @staticmethod
    def check_price_alerts(symbol: str, price: float) -> List[Alert]:
        """
        检查价格告警
        
        Args:
            symbol: 品种代码
            price: 当前价格
            
        Returns:
            List[Alert]: 被触发的告警列表
        """
        with SQLiteSessionLocal() as db:
            alerts = db.query(Alert).filter(
                Alert.symbol == symbol,
                Alert.status == "active",
                Alert.alert_type == "price"
            ).all()
            
            triggered = []
            for alert in alerts:
                should_trigger = False
                
                if alert.condition_type == "greater_than" and price >= alert.condition_value:
                    should_trigger = True
                elif alert.condition_type == "less_than" and price <= alert.condition_value:
                    should_trigger = True
                elif alert.condition_type == "equals" and abs(price - float(alert.condition_value)) < 0.001:
                    should_trigger = True
                
                if should_trigger:
                    # 更新告警状态为 triggered
                    alert.status = "triggered"
                    alert.triggered_at = datetime.utcnow()
                    alert.updated_at = datetime.utcnow()
                    triggered.append(alert)
            
            if triggered:
                db.commit()
                # 刷新对象状态
                for alert in triggered:
                    db.refresh(alert)
            
            return triggered