package rag

import (
	"eta/eta_api/controllers"
	"eta/eta_api/models/system"
	"eta/eta_api/services/llm/facade"
	"eta/eta_api/utils"
	"eta/eta_api/utils/ws"
	"github.com/gorilla/websocket"
	"net"
	"net/http"
	"time"
)

type ChatController struct {
	controllers.BaseAuthController
}

func (cc *ChatController) Prepare() {
	cc.SysUser = cc.Ctx.Input.GetData("admin").(*system.Admin)
	if cc.SysUser == nil || cc.SysUser.AdminId == 0 {
		utils.FileLog.Error("用户信息不存在")
		cc.Ctx.ResponseWriter.WriteHeader(http.StatusBadRequest)
		return
	}
}

// ChatConnect @Title 知识库问答创建对话连接
// @Description 知识库问答创建对话连接
// @Success 101 {object} response.ListResp
// @router /chat/connect [get]
func (cc *ChatController) ChatConnect() {
	if !ws.Allow(cc.SysUser.AdminId, ws.CONNECT_LIMITER) {
		utils.FileLog.Error("WebSocket连接太频繁,主动拒绝链接")
		cc.Ctx.ResponseWriter.WriteHeader(http.StatusTooManyRequests)
		return
	}
	wsCon, err := webSocketHandler(cc.Ctx.ResponseWriter, cc.Ctx.Request)
	if err != nil {
		utils.FileLog.Error("WebSocket连接失败:", err)
		cc.Ctx.ResponseWriter.WriteHeader(http.StatusBadRequest)
		return
	}
	facade.AddSession(cc.SysUser.AdminId, wsCon)
}

// upGrader 用于将HTTP连接升级为WebSocket连接
var upGrader = websocket.Upgrader{
	ReadBufferSize:  1024,
	WriteBufferSize: 1024,
	CheckOrigin: func(r *http.Request) bool {
		return true
	},
}

// WebSocketHandler 处理WebSocket连接
func webSocketHandler(w http.ResponseWriter, r *http.Request) (conn *websocket.Conn, err error) {
	conn, err = upGrader.Upgrade(w, r, nil)
	if err != nil {
		utils.FileLog.Error("升级协议失败:WebSocket:%s", err.Error())
		return
	}
	// 获取底层 TCP 连接并设置保活
	if tcpConn, ok := conn.NetConn().(*net.TCPConn); ok {
		_ = tcpConn.SetKeepAlive(true)
		_ = tcpConn.SetKeepAlivePeriod(90 * time.Second)
		utils.FileLog.Info("TCP KeepAlive 已启用")
	}
	_ = conn.SetReadDeadline(time.Now().Add(ws.ReadTimeout))
	return
}