from typing import List, Optional
from sqlalchemy.orm import Session
from datetime import datetime

from app.models.alert import AlertRule, AlertRecord, WorkOrder
from app.models.project import ClassificationProject, ClassificationResult
from app.models.risk import RiskAssessment


def init_builtin_alert_rules(db: Session):
    if db.query(AlertRule).first():
        return
    rules = [
        AlertRule(name="L5字段数量突增", trigger_condition="l5_count", threshold=5, severity="high"),
        AlertRule(name="项目风险分过高", trigger_condition="risk_score", threshold=80, severity="critical"),
        AlertRule(name="Schema新增敏感字段", trigger_condition="schema_change", threshold=1, severity="medium"),
    ]
    for r in rules:
        db.add(r)
    db.commit()


def check_alerts(db: Session) -> List[AlertRecord]:
    """Run alert checks and create records."""
    rules = db.query(AlertRule).filter(AlertRule.is_active == True).all()
    records = []
    for rule in rules:
        if rule.trigger_condition == "l5_count":
            projects = db.query(ClassificationProject).all()
            for p in projects:
                l5_count = db.query(ClassificationResult).filter(
                    ClassificationResult.project_id == p.id,
                    ClassificationResult.level_id.isnot(None),
                ).join(ClassificationResult.level).filter(
                    ClassificationResult.level.has(code="L5")
                ).count()
                if l5_count >= rule.threshold:
                    rec = AlertRecord(
                        rule_id=rule.id,
                        title=f"项目 {p.name} L5字段数量达到 {l5_count}",
                        content=f"阈值: {rule.threshold}",
                        severity=rule.severity,
                    )
                    db.add(rec)
                    records.append(rec)
        elif rule.trigger_condition == "risk_score":
            risks = db.query(RiskAssessment).filter(
                RiskAssessment.entity_type == "project",
                RiskAssessment.risk_score >= rule.threshold,
            ).all()
            for rsk in risks:
                rec = AlertRecord(
                    rule_id=rule.id,
                    title=f"项目 {rsk.entity_name} 风险分 {rsk.risk_score}",
                    content=f"阈值: {rule.threshold}",
                    severity=rule.severity,
                )
                db.add(rec)
                records.append(rec)
    db.commit()
    return records


def create_work_order(db: Session, alert_id: int, title: str, description: str, assignee_id: Optional[int] = None) -> WorkOrder:
    wo = WorkOrder(
        alert_id=alert_id,
        title=title,
        description=description,
        assignee_id=assignee_id,
    )
    db.add(wo)
    db.commit()
    db.refresh(wo)
    return wo


def update_work_order_status(db: Session, wo_id: int, status: str, resolution: str = None) -> WorkOrder:
    wo = db.query(WorkOrder).filter(WorkOrder.id == wo_id).first()
    if wo:
        wo.status = status
        if resolution:
            wo.resolution = resolution
        if status == "resolved":
            wo.resolved_at = datetime.utcnow()
            # Also resolve linked alert
            if wo.alert_id:
                alert = db.query(AlertRecord).filter(AlertRecord.id == wo.alert_id).first()
                if alert:
                    alert.status = "resolved"
        db.commit()
        db.refresh(wo)
    return wo