"""预警规则配置"""
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.orm import Session
from app.database import get_db
from app.auth_middleware import require_auth, require_role
from app.models import KPIAlert, KPIDefinition, KPIValue

router = APIRouter(prefix="/api/cma/alert-rules", tags=["预警规则"],
    dependencies=[Depends(require_role("ceo", "finance"))],
)

@router.get("")
def list_rules(kpi_id: int = None, db: Session = Depends(get_db)):
    """获取预警规则（从KPI定义中读取阈值配置）"""
    query = db.query(KPIDefinition).filter(KPIDefinition.status == "active")
    if kpi_id:
        query = query.filter(KPIDefinition.id == kpi_id)
    rules = []
    for k in query.all():
        if k.threshold_green or k.threshold_yellow or k.threshold_red:
            rules.append({
                "kpi_id": k.id,
                "kpi_name": k.kpi_name,
                "threshold_green": k.threshold_green,
                "threshold_yellow": k.threshold_yellow,
                "threshold_red": k.threshold_red,
            })
    return {"data": rules}

@router.post("/check/{kpi_id}")
def check_alert(kpi_id: int, db: Session = Depends(get_db)):
    """检查指定KPI是否需要触发预警"""
    kpi = db.query(KPIDefinition).filter(KPIDefinition.id == kpi_id).first()
    if not kpi:
        raise HTTPException(404, "KPI不存在")
    
    latest = db.query(KPIValue).filter(KPIValue.kpi_id == kpi_id).order_by(KPIValue.period.desc()).first()
    if not latest or not latest.actual_value:
        return {"alert": False, "message": "无数据"}
    
    val = latest.actual_value
    level = "green"
    
    # 简单阈值判定
    red = kpi.threshold_red
    yellow = kpi.threshold_yellow
    
    # 红灯判断: <3000000 表示低于300万触发红灯
    if red:
        if "<" in red:
            limit = float(red.split("<")[1].strip())
            if val < limit: level = "red"
        elif ">" in red:
            limit = float(red.split(">")[1].strip())
            if val > limit: level = "red"
    
    # 黄灯判断（红灯未触发时）
    if level == "green" and yellow:
        if "<" in yellow:
            limit = float(yellow.split("<")[1].strip())
            if val < limit: level = "yellow"
        elif ">" in yellow:
            limit = float(yellow.split(">")[1].strip())
            if val > limit: level = "yellow"
    
    if level != "green":
        alert = KPIAlert(
            kpi_id=kpi_id, kpi_value_id=latest.id,
            alert_level=level,
            alert_message=f"{kpi.kpi_name}当前值为{val}，触发{level}预警",
        )
        db.add(alert)
        db.commit()
        return {"alert": True, "level": level, "message": alert.alert_message}
    
    return {"alert": False, "level": "green", "message": "正常"}