"""Alerts API endpoints."""

from typing import List, Optional
from fastapi import APIRouter, HTTPException, Depends
from pydantic import BaseModel
from datetime import datetime
from sqlalchemy import select

from src.core.database import Alert, get_database

router = APIRouter()


def get_alert_manager():
    """Get alert manager instance."""
    from src.alerts.manager import get_alert_manager as _get_alert_manager
    return _get_alert_manager()


class AlertCreate(BaseModel):
    """Create alert request."""
    name: str
    alert_type: str  # price, indicator, risk, system
    condition: dict


class AlertUpdate(BaseModel):
    """Update alert request."""
    name: Optional[str] = None
    condition: Optional[dict] = None
    enabled: Optional[bool] = None


class AlertResponse(BaseModel):
    """Alert response."""
    id: int
    name: str
    alert_type: str
    condition: dict
    enabled: bool
    triggered: bool
    triggered_at: Optional[datetime] = None
    created_at: datetime
    updated_at: datetime

    class Config:
        from_attributes = True


@router.get("/", response_model=List[AlertResponse])
async def list_alerts(
    enabled_only: bool = False,
    manager=Depends(get_alert_manager)
):
    """List all alerts."""
    try:
        alerts = await manager.list_alerts(enabled_only=enabled_only)
        return [AlertResponse.model_validate(alert) for alert in alerts]
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.post("/", response_model=AlertResponse)
async def create_alert(
    alert_data: AlertCreate,
    manager=Depends(get_alert_manager)
):
    """Create a new alert."""
    try:
        alert = await manager.create_alert(
            name=alert_data.name,
            alert_type=alert_data.alert_type,
            condition=alert_data.condition
        )
        return AlertResponse.model_validate(alert)
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.get("/{alert_id}", response_model=AlertResponse)
async def get_alert(alert_id: int):
    """Get alert by ID."""
    try:
        db = get_database()
        async with db.get_session() as session:
            stmt = select(Alert).where(Alert.id == alert_id)
            result = await session.execute(stmt)
            alert = result.scalar_one_or_none()
            if not alert:
                raise HTTPException(status_code=404, detail="Alert not found")
            return AlertResponse.model_validate(alert)
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.put("/{alert_id}", response_model=AlertResponse)
async def update_alert(alert_id: int, alert_data: AlertUpdate):
    """Update an alert."""
    try:
        db = get_database()
        async with db.get_session() as session:
            stmt = select(Alert).where(Alert.id == alert_id)
            result = await session.execute(stmt)
            alert = result.scalar_one_or_none()
            if not alert:
                raise HTTPException(status_code=404, detail="Alert not found")
            
            if alert_data.name is not None:
                alert.name = alert_data.name
            if alert_data.condition is not None:
                alert.condition = alert_data.condition
            if alert_data.enabled is not None:
                alert.enabled = alert_data.enabled
            
            await session.commit()
            await session.refresh(alert)
            return AlertResponse.model_validate(alert)
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))


@router.delete("/{alert_id}")
async def delete_alert(alert_id: int):
    """Delete an alert."""
    try:
        db = get_database()
        async with db.get_session() as session:
            stmt = select(Alert).where(Alert.id == alert_id)
            result = await session.execute(stmt)
            alert = result.scalar_one_or_none()
            if not alert:
                raise HTTPException(status_code=404, detail="Alert not found")
            
            await session.delete(alert)
            await session.commit()
            return {"status": "deleted", "alert_id": alert_id}
    except HTTPException:
        raise
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))