backend/websocket/websocket_handler.py

"""
WebSocket Handler for AegisLM Real-time Updates.

Provides real-time evaluation status updates, progress tracking,
and live result streaming to connected frontend clients.
"""

import json
import asyncio
import logging
from typing import Dict, Set, Optional, Any
from datetime import datetime
from fastapi import WebSocket, WebSocketDisconnect
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select

from db_models.evaluation import Evaluation, EvaluationStatus
from core.security import verify_websocket_token
from services.evaluation_service import EvaluationService

logger = logging.getLogger(__name__)


class WebSocketManager:
    """Manages WebSocket connections and room-based broadcasting."""
    
    def __init__(self):
        self.active_connections: Dict[str, WebSocket] = {}
        self.rooms: Dict[str, Set[str]] = {}  # room_id -> connection_ids
        self.connection_rooms: Dict[str, str] = {}  # connection_id -> room_id
    
    async def connect(self, websocket: WebSocket, connection_id: str):
        """Accept and register WebSocket connection."""
        await websocket.accept()
        self.active_connections[connection_id] = websocket
        logger.info(f"✅ WebSocket connected: {connection_id}")
    
    async def disconnect(self, connection_id: str):
        """Remove WebSocket connection."""
        if connection_id in self.active_connections:
            # Remove from room
            if connection_id in self.connection_rooms:
                room_id = self.connection_rooms[connection_id]
                if room_id in self.rooms and connection_id in self.rooms[room_id]:
                    self.rooms[room_id].remove(connection_id)
                    if not self.rooms[room_id]:
                        del self.rooms[room_id]
                del self.connection_rooms[connection_id]
            
            # Remove connection
            del self.active_connections[connection_id]
            logger.info(f"❌ WebSocket disconnected: {connection_id}")
    
    async def join_room(self, connection_id: str, room_id: str):
        """Add connection to a room."""
        if room_id not in self.rooms:
            self.rooms[room_id] = set()
        
        # Remove from previous room if any
        if connection_id in self.connection_rooms:
            old_room = self.connection_rooms[connection_id]
            if old_room in self.rooms and connection_id in self.rooms[old_room]:
                self.rooms[old_room].remove(connection_id)
        
        # Add to new room
        self.rooms[room_id].add(connection_id)
        self.connection_rooms[connection_id] = room_id
        logger.info(f"📡 Connection {connection_id} joined room {room_id}")
    
    async def leave_room(self, connection_id: str):
        """Remove connection from current room."""
        if connection_id in self.connection_rooms:
            room_id = self.connection_rooms[connection_id]
            if room_id in self.rooms and connection_id in self.rooms[room_id]:
                self.rooms[room_id].remove(connection_id)
                if not self.rooms[room_id]:
                    del self.rooms[room_id]
            del self.connection_rooms[connection_id]
    
    async def send_to_connection(self, connection_id: str, message: dict):
        """Send message to specific connection."""
        if connection_id in self.active_connections:
            websocket = self.active_connections[connection_id]
            try:
                await websocket.send_text(json.dumps(message))
            except Exception as e:
                logger.error(f"❌ Failed to send to {connection_id}: {e}")
                await self.disconnect(connection_id)
    
    async def broadcast_to_room(self, room_id: str, message: dict):
        """Broadcast message to all connections in a room."""
        if room_id in self.rooms:
            disconnected = set()
            for connection_id in self.rooms[room_id]:
                if connection_id in self.active_connections:
                    websocket = self.active_connections[connection_id]
                    try:
                        await websocket.send_text(json.dumps(message))
                    except Exception as e:
                        logger.error(f"❌ Failed to send to {connection_id}: {e}")
                        disconnected.add(connection_id)
                else:
                    disconnected.add(connection_id)
            
            # Clean up disconnected connections
            for connection_id in disconnected:
                await self.disconnect(connection_id)


# Global WebSocket manager
websocket_manager = WebSocketManager()


class EvaluationWebSocketHandler:
    """Handles WebSocket connections for evaluation updates."""
    
    def __init__(self, db: AsyncSession):
        self.db = db
        self.evaluation_service = EvaluationService(db)
    
    async def handle_connection(
        self, 
        websocket: WebSocket, 
        job_id: str,
        token: Optional[str] = None
    ):
        """Handle WebSocket connection for evaluation updates."""
        connection_id = f"eval_{job_id}_{datetime.utcnow().timestamp()}"
        
        try:
            # Authenticate connection
            user = await self._authenticate_websocket(websocket, token)
            if not user:
                await websocket.close(code=4001, reason="Authentication failed")
                return
            
            # Verify evaluation access
            evaluation = await self._get_evaluation(job_id, user.id)
            if not evaluation:
                await websocket.close(code=4004, reason="Evaluation not found")
                return
            
            # Connect and join room
            await websocket_manager.connect(websocket, connection_id)
            await websocket_manager.join_room(connection_id, f"evaluation_{job_id}")
            
            # Send initial status
            initial_status = await self._get_evaluation_status(job_id)
            await websocket_manager.send_to_connection(connection_id, {
                "type": "status_update",
                "data": initial_status
            })
            
            # Start status monitoring loop
            await self._status_monitoring_loop(connection_id, job_id)
            
        except WebSocketDisconnect:
            logger.info(f"🔌 WebSocket disconnected for evaluation {job_id}")
        except Exception as e:
            logger.error(f"❌ WebSocket error for evaluation {job_id}: {e}")
            await websocket.close(code=4000, reason="Internal server error")
        finally:
            await websocket_manager.disconnect(connection_id)
    
    async def _authenticate_websocket(self, websocket: WebSocket, token: Optional[str]) -> Optional[Any]:
        """Authenticate WebSocket connection."""
        if not token:
            # Try to get token from query params
            token = websocket.query_params.get("token") if hasattr(websocket, 'query_params') else None
        
        if not token:
            return None
        
        try:
            from db_models.user import User
            user_id = verify_websocket_token(token)
            if user_id:
                user = await self.db.get(User, user_id)
                return user
        except Exception as e:
            logger.error(f"❌ WebSocket authentication failed: {e}")
        
        return None
    
    async def _get_evaluation(self, job_id: str, user_id: int) -> Optional[Evaluation]:
        """Get evaluation and verify user access."""
        try:
            result = await self.db.execute(
                select(Evaluation).where(
                    Evaluation.job_id == job_id,
                    Evaluation.user_id == user_id
                )
            )
            return result.scalar_one_or_none()
        except Exception as e:
            logger.error(f"❌ Failed to get evaluation {job_id}: {e}")
            return None
    
    async def _get_evaluation_status(self, job_id: str) -> dict:
        """Get current evaluation status."""
        try:
            evaluation = await self.evaluation_service.get_evaluation_by_job_id(job_id, 0)  # user_id not needed for status
            
            if not evaluation:
                return {
                    "job_id": job_id,
                    "status": "not_found",
                    "progress": 0.0,
                    "error_message": "Evaluation not found"
                }
            
            # Calculate progress based on status
            progress = 0.0
            if evaluation.status == EvaluationStatus.COMPLETED:
                progress = 100.0
            elif evaluation.status == EvaluationStatus.RUNNING:
                # Estimate progress based on execution time
                if evaluation.started_at and evaluation.execution_time_ms:
                    elapsed = (datetime.utcnow() - evaluation.started_at).total_seconds() * 1000
                    progress = min(95.0, (elapsed / evaluation.execution_time_ms) * 100)
                else:
                    progress = 25.0  # Just started
            elif evaluation.status == EvaluationStatus.FAILED:
                progress = 0.0
            
            return {
                "job_id": evaluation.job_id,
                "status": evaluation.status.value,
                "progress": progress,
                "started_at": evaluation.started_at.isoformat() if evaluation.started_at else None,
                "completed_at": evaluation.completed_at.isoformat() if evaluation.completed_at else None,
                "error_message": evaluation.error_message,
                "total_attacks": evaluation.total_attacks,
                "successful_attacks": evaluation.successful_attacks,
                "current_phase": self._get_current_phase(evaluation.status)
            }
        except Exception as e:
            logger.error(f"❌ Failed to get evaluation status {job_id}: {e}")
            return {
                "job_id": job_id,
                "status": "error",
                "progress": 0.0,
                "error_message": str(e)
            }
    
    def _get_current_phase(self, status: EvaluationStatus) -> str:
        """Get current execution phase based on status."""
        phase_mapping = {
            EvaluationStatus.PENDING: "queued",
            EvaluationStatus.RUNNING: "executing_attacks",
            EvaluationStatus.COMPLETED: "completed",
            EvaluationStatus.FAILED: "failed",
            EvaluationStatus.CANCELLED: "cancelled"
        }
        return phase_mapping.get(status, "unknown")
    
    async def _status_monitoring_loop(self, connection_id: str, job_id: str):
        """Monitor evaluation status and send updates."""
        last_status = None
        
        while connection_id in websocket_manager.active_connections:
            try:
                current_status = await self._get_evaluation_status(job_id)
                
                # Send update if status changed
                if current_status != last_status:
                    await websocket_manager.send_to_connection(connection_id, {
                        "type": "status_update",
                        "data": current_status
                    })
                    last_status = current_status
                
                # Stop monitoring if evaluation is complete
                if current_status["status"] in ["completed", "failed", "cancelled"]:
                    # Send final update
                    await websocket_manager.send_to_connection(connection_id, {
                        "type": "evaluation_complete",
                        "data": current_status
                    })
                    break
                
                # Poll every 5 seconds
                await asyncio.sleep(5)
                
            except Exception as e:
                logger.error(f"❌ Status monitoring error for {job_id}: {e}")
                break
    
    async def broadcast_evaluation_update(self, job_id: str, update_data: dict):
        """Broadcast evaluation update to all connected clients."""
        room_id = f"evaluation_{job_id}"
        await websocket_manager.broadcast_to_room(room_id, {
            "type": "evaluation_update",
            "data": update_data
        })
    
    async def broadcast_progress_update(self, job_id: str, progress: float, phase: str):
        """Broadcast progress update."""
        room_id = f"evaluation_{job_id}"
        await websocket_manager.broadcast_to_room(room_id, {
            "type": "progress_update",
            "data": {
                "job_id": job_id,
                "progress": progress,
                "current_phase": phase,
                "timestamp": datetime.utcnow().isoformat()
            }
        })


# Global WebSocket handler factory
def get_websocket_handler(db: AsyncSession) -> EvaluationWebSocketHandler:
    """Get WebSocket handler instance."""
    return EvaluationWebSocketHandler(db)


# Utility functions for broadcasting
async def broadcast_evaluation_status(job_id: str, status: str, progress: float = None):
    """Broadcast evaluation status update."""
    update_data = {
        "job_id": job_id,
        "status": status,
        "timestamp": datetime.utcnow().isoformat()
    }
    
    if progress is not None:
        update_data["progress"] = progress
    
    room_id = f"evaluation_{job_id}"
    await websocket_manager.broadcast_to_room(room_id, {
        "type": "status_update",
        "data": update_data
    })


async def broadcast_evaluation_completed(job_id: str, results: dict):
    """Broadcast evaluation completion with results."""
    room_id = f"evaluation_{job_id}"
    await websocket_manager.broadcast_to_room(room_id, {
        "type": "evaluation_completed",
        "data": {
            "job_id": job_id,
            "status": "completed",
            "results": results,
            "timestamp": datetime.utcnow().isoformat()
        }
    })