# backend/app/api/v2/websocket.py
"""
WebSocket API 接口
支持连接状态查询、订阅管理、推送统计
"""

from typing import Optional
from fastapi import APIRouter, WebSocket, WebSocketDisconnect, Depends, Query, HTTPException
from sqlalchemy.orm import Session
from app.db.base import get_db
from app.middleware.auth import get_current_user
from app.models.user import User
from app.websocket.connection_manager import connection_manager, websocket_handler
from app.services.push_service import push_service
from app.services.auth_service import verify_token
import logging

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api/v2/ws", tags=["WebSocket 服务"])


# ============== WebSocket 连接路由 ==============

@router.websocket("/quote")
async def websocket_quote_endpoint(
    websocket: WebSocket,
    token: str = Query(..., description="认证 Token"),
    db: Session = Depends(get_db)
):
    """
    WebSocket 行情推送连接
    
    连接地址: WS /api/v2/ws/quote?token={token}
    
    客户端操作:
    - subscribe: 订阅品种 {"action": "subscribe", "symbols": ["IF2406"]}
    - unsubscribe: 取消订阅 {"action": "unsubscribe", "symbols": ["IF2406"]}
    - heartbeat: 心跳 {"action": "heartbeat"}
    - query: 查询订阅 {"action": "query"}
    
    服务端推送:
    - quote: 行情推送 {"type": "quote", "symbol": "IF2406", "data": {...}}
    - kline: K 线推送 {"type": "kline", "symbol": "IF2406", "period": "1m", "data": {...}}
    - system: 系统消息 {"type": "system", "event": "connected", ...}
    """
    # 认证
    user = await verify_token(token)
    if not user:
        await websocket.close(code=4001, reason="认证失败")
        return
    
    # 处理 WebSocket 消息
    await websocket_handler(websocket, user.id)


# ============== HTTP API（WebSocket 管理） ==============

@router.get("/connections", summary="查询连接统计")
async def get_connection_statistics(
    current_user: User = Depends(get_current_user)
):
    """
    查询 WebSocket 连接统计
    
    包括连接数、用户数、订阅数、消息数等
    """
    try:
        stats = connection_manager.get_statistics()
        
        return {
            "connections": stats,
            "push_service": push_service.get_statistics()
        }
    
    except Exception as e:
        logger.error(f"❌ 查询连接统计失败: {e}")
        raise HTTPException(status_code=500, detail=f"查询连接统计失败: {str(e)}")


@router.get("/user/{user_id}/subscriptions", summary="查询用户订阅")
async def get_user_subscriptions(
    user_id: int,
    current_user: User = Depends(get_current_user)
):
    """
    查询用户的 WebSocket 订阅列表
    
    仅管理员或用户本人可查询
    """
    try:
        # 权限检查
        if current_user.id != user_id and current_user.role != "admin":
            raise HTTPException(status_code=403, detail="无权限查询其他用户的订阅")
        
        subscriptions = connection_manager.get_user_subscriptions(user_id)
        
        return {
            "user_id": user_id,
            "subscriptions": subscriptions,
            "count": len(subscriptions)
        }
    
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"❌ 查询用户订阅失败: {e}")
        raise HTTPException(status_code=500, detail=f"查询用户订阅失败: {str(e)}")


@router.get("/symbol/{symbol}/subscribers", summary="查询品种订阅用户")
async def get_symbol_subscribers(
    symbol: str,
    current_user: User = Depends(get_current_user)
):
    """
    查询订阅某品种的用户列表
    
    仅管理员可查询
    """
    try:
        # 权限检查
        if current_user.role != "admin":
            raise HTTPException(status_code=403, detail="无权限查询品种订阅用户")
        
        stats = connection_manager.get_statistics()
        symbol_subscribers = stats.get("symbol_subscribers", {})
        
        user_count = symbol_subscribers.get(symbol, 0)
        
        return {
            "symbol": symbol,
            "subscriber_count": user_count
        }
    
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"❌ 查询品种订阅用户失败: {e}")
        raise HTTPException(status_code=500, detail=f"查询品种订阅用户失败: {str(e)}")


@router.post("/broadcast", summary="广播系统消息")
async def broadcast_system_message(
    message: dict,
    current_user: User = Depends(get_current_user)
):
    """
    广播系统消息
    
    仅管理员可操作
    """
    try:
        # 权限检查
        if current_user.role != "admin":
            raise HTTPException(status_code=403, detail="无权限广播消息")
        
        # 广播消息
        await connection_manager.broadcast({
            "type": "system",
            "event": "broadcast",
            "message": message,
            "time": datetime.now().isoformat()
        })
        
        logger.info(f"✅ 管理员 {current_user.id} 广播消息: {message}")
        
        return {"status": "success", "message": "消息已广播"}
    
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"❌ 广播消息失败: {e}")
        raise HTTPException(status_code=500, detail=f"广播消息失败: {str(e)}")


@router.post("/publish/quote", summary="发布行情更新")
async def publish_quote_update(
    symbol: str = Query(..., description="品种代码"),
    quote_data: dict = None,
    current_user: User = Depends(get_current_user)
):
    """
    发布行情更新（手动触发）
    
    仅管理员可操作
    """
    try:
        # 权限检查
        if current_user.role != "admin":
            raise HTTPException(status_code=403, detail="无权限发布行情")
        
        # 发布行情
        await push_service.publish_quote(symbol, quote_data)
        
        logger.info(f"✅ 管理员 {current_user.id} 发布行情: {symbol}")
        
        return {"status": "success", "message": f"行情已发布: {symbol}"}
    
    except HTTPException:
        raise
    except Exception as e:
        logger.error(f"❌ 发布行情失败: {e}")
        raise HTTPException(status_code=500, detail=f"发布行情失败: {str(e)}")


# ============== 导入依赖 ==============

from datetime import datetime