package net

import (
	"net"
	"strconv"

	"cellbot/internal/engine"
	"cellbot/internal/protocol"

	"github.com/bytedance/sonic"
	"github.com/valyala/fasthttp"
	"go.uber.org/zap"
)

// Server HTTP服务器
type Server struct {
	host       string
	port       int
	logger     *zap.Logger
	botManager *protocol.BotManager
	eventBus   *engine.EventBus
	wsManager  *WebSocketManager
	server     *fasthttp.Server
}

// NewServer 创建HTTP服务器
func NewServer(host string, port int, logger *zap.Logger, botManager *protocol.BotManager, eventBus *engine.EventBus) *Server {
	wsManager := NewWebSocketManager(logger, eventBus)
	return &Server{
		host:       host,
		port:       port,
		logger:     logger.Named("server"),
		botManager: botManager,
		eventBus:   eventBus,
		wsManager:  wsManager,
	}
}

// Start 启动服务器
func (s *Server) Start() error {
	s.server = &fasthttp.Server{
		Handler:            s.requestHandler,
		MaxConnsPerIP:      1000,
		MaxRequestsPerConn: 1000,
		ReadTimeout:        0,
		WriteTimeout:       0,
		IdleTimeout:        0,
		DisableKeepalive:   false,
	}

	addr := net.JoinHostPort(s.host, strconv.Itoa(s.port))
	s.logger.Info("Starting HTTP server", zap.String("address", addr))

	go func() {
		if err := s.server.ListenAndServe(addr); err != nil {
			s.logger.Error("Server error", zap.Error(err))
		}
	}()

	return nil
}

// Stop 停止服务器
func (s *Server) Stop() error {
	if s.server != nil {
		s.logger.Info("Stopping HTTP server")
		return s.server.Shutdown()
	}
	return nil
}

// requestHandler 请求处理器
func (s *Server) requestHandler(ctx *fasthttp.RequestCtx) {
	path := string(ctx.Path())
	method := string(ctx.Method())

	s.logger.Debug("Received request",
		zap.String("path", path),
		zap.String("method", method))

	// 路由处理
	switch path {
	case "/":
		s.handleRoot(ctx)
	case "/health":
		s.handleHealth(ctx)
	case "/bots":
		s.handleBots(ctx)
	case "/bots/create":
		s.handleCreateBot(ctx)
	case "/events/publish":
		s.handlePublishEvent(ctx)
	case "/events/subscribe":
		s.handleSubscribeEvent(ctx)
	default:
		ctx.Error("Not Found", fasthttp.StatusNotFound)
	}
}

// handleRoot 根路径处理
func (s *Server) handleRoot(ctx *fasthttp.RequestCtx) {
	ctx.SetContentType("application/json")
	ctx.SetBodyString(`{"message":"CellBot Server","version":"1.0.0"}`)
}

// handleHealth 健康检查
func (s *Server) handleHealth(ctx *fasthttp.RequestCtx) {
	ctx.SetContentType("application/json")
	ctx.SetBodyString(`{"status":"ok"}`)
}

// BotInfo 机器人信息结构
type BotInfo struct {
	ID        string `json:"id"`
	Name      string `json:"name"`
	Version   string `json:"version"`
	Status    string `json:"status"`
	SelfID    string `json:"self_id"`
	Connected bool   `json:"connected"`
}

// handleBots 获取机器人列表
func (s *Server) handleBots(ctx *fasthttp.RequestCtx) {
	bots := s.botManager.GetAll()
	ctx.SetContentType("application/json")

	// 构建机器人信息列表
	botInfos := make([]BotInfo, 0, len(bots))
	for _, bot := range bots {
		botInfos = append(botInfos, BotInfo{
			ID:        bot.GetID(),
			Name:      bot.Name(),
			Version:   bot.Version(),
			Status:    string(bot.GetStatus()),
			SelfID:    bot.GetSelfID(),
			Connected: bot.IsConnected(),
		})
	}

	// 序列化为JSON
	response := map[string]interface{}{
		"bots":  botInfos,
		"count": len(botInfos),
	}

	data, err := sonic.Marshal(response)
	if err != nil {
		s.logger.Error("Failed to marshal bots response", zap.Error(err))
		ctx.Error("Internal Server Error", fasthttp.StatusInternalServerError)
		return
	}

	ctx.SetBody(data)
}

// CreateBotRequest 创建机器人请求
type CreateBotRequest struct {
	ID       string                 `json:"id"`
	Protocol string                 `json:"protocol"`
	Config   map[string]interface{} `json:"config"`
}

// handleCreateBot 创建机器人
func (s *Server) handleCreateBot(ctx *fasthttp.RequestCtx) {
	if string(ctx.Method()) != "POST" {
		ctx.Error("Method Not Allowed", fasthttp.StatusMethodNotAllowed)
		return
	}

	ctx.SetContentType("application/json")

	// 解析请求体
	var req CreateBotRequest
	if err := sonic.Unmarshal(ctx.PostBody(), &req); err != nil {
		s.logger.Error("Failed to parse create bot request", zap.Error(err))
		response := map[string]interface{}{
			"success": false,
			"error":   "Invalid request body",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		ctx.SetBody(data)
		return
	}

	// 验证必需字段
	if req.ID == "" {
		response := map[string]interface{}{
			"success": false,
			"error":   "Bot ID is required",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		ctx.SetBody(data)
		return
	}

	if req.Protocol == "" {
		response := map[string]interface{}{
			"success": false,
			"error":   "Protocol is required",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		ctx.SetBody(data)
		return
	}

	// 检查机器人是否已存在
	if _, exists := s.botManager.Get(req.ID); exists {
		response := map[string]interface{}{
			"success": false,
			"error":   "Bot with this ID already exists",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusConflict)
		ctx.SetBody(data)
		return
	}

	// TODO: 根据协议类型创建相应的机器人实例
	// 这里需要协议工厂来创建不同类型的机器人
	// 目前返回成功但提示需要实现协议适配器

	s.logger.Info("Bot creation requested",
		zap.String("bot_id", req.ID),
		zap.String("protocol", req.Protocol))

	response := map[string]interface{}{
		"success": true,
		"message": "Bot creation queued (protocol adapter implementation required)",
		"bot_id":  req.ID,
	}

	data, _ := sonic.Marshal(response)
	ctx.SetStatusCode(fasthttp.StatusAccepted)
	ctx.SetBody(data)
}

// handlePublishEvent 发布事件
func (s *Server) handlePublishEvent(ctx *fasthttp.RequestCtx) {
	if string(ctx.Method()) != "POST" {
		ctx.Error("Method Not Allowed", fasthttp.StatusMethodNotAllowed)
		return
	}

	ctx.SetContentType("application/json")

	// 解析请求体为事件对象
	var event protocol.BaseEvent
	if err := sonic.Unmarshal(ctx.PostBody(), &event); err != nil {
		s.logger.Error("Failed to parse event", zap.Error(err))
		response := map[string]interface{}{
			"success": false,
			"error":   "Invalid event format",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		ctx.SetBody(data)
		return
	}

	// 验证事件类型
	if event.Type == "" {
		response := map[string]interface{}{
			"success": false,
			"error":   "Event type is required",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		ctx.SetBody(data)
		return
	}

	// 如果没有时间戳，使用当前时间
	if event.Timestamp == 0 {
		event.Timestamp = ctx.Time().Unix()
	}

	// 确保Data字段不为nil
	if event.Data == nil {
		event.Data = make(map[string]interface{})
	}

	s.logger.Info("Publishing event",
		zap.String("type", string(event.Type)),
		zap.String("detail_type", event.DetailType),
		zap.String("self_id", event.SelfID))

	// 发布到事件总线
	s.eventBus.Publish(&event)

	response := map[string]interface{}{
		"success":   true,
		"message":   "Event published successfully",
		"timestamp": event.Timestamp,
	}

	data, _ := sonic.Marshal(response)
	ctx.SetBody(data)
}

// handleSubscribeEvent 订阅事件（WebSocket升级）
func (s *Server) handleSubscribeEvent(ctx *fasthttp.RequestCtx) {
	// 检查是否为WebSocket升级请求
	if !ctx.IsGet() {
		ctx.Error("Method Not Allowed", fasthttp.StatusMethodNotAllowed)
		return
	}

	// 检查是否为WebSocket升级请求
	if string(ctx.Request.Header.Peek("Upgrade")) != "websocket" {
		ctx.SetContentType("application/json")
		response := map[string]interface{}{
			"success": false,
			"error":   "WebSocket upgrade required",
			"message": "This endpoint requires WebSocket connection",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusBadRequest)
		ctx.SetBody(data)
		return
	}

	// 获取订阅者ID（可选）
	subscriberID := string(ctx.QueryArgs().Peek("subscriber_id"))
	if subscriberID == "" {
		subscriberID = "event-subscriber"
	}

	// 获取要订阅的事件类型（可选，为空则订阅所有类型）
	eventTypeStr := string(ctx.QueryArgs().Peek("event_type"))

	s.logger.Info("WebSocket event subscription request",
		zap.String("subscriber_id", subscriberID),
		zap.String("event_type", eventTypeStr),
		zap.String("remote_addr", ctx.RemoteAddr().String()))

	// 升级为WebSocket连接
	wsConn, err := s.wsManager.UpgradeWebSocket(ctx)
	if err != nil {
		s.logger.Error("Failed to upgrade WebSocket", zap.Error(err))
		ctx.SetContentType("application/json")
		response := map[string]interface{}{
			"success": false,
			"error":   "Failed to upgrade WebSocket connection",
		}
		data, _ := sonic.Marshal(response)
		ctx.SetStatusCode(fasthttp.StatusInternalServerError)
		ctx.SetBody(data)
		return
	}

	// 订阅所有主要事件类型
	eventTypes := []protocol.EventType{
		protocol.EventTypeMessage,
		protocol.EventTypeNotice,
		protocol.EventTypeRequest,
		protocol.EventTypeMeta,
		protocol.EventTypeMessageSent,
		protocol.EventTypeNoticeSent,
		protocol.EventTypeRequestSent,
	}

	// 如果指定了事件类型，只订阅该类型
	if eventTypeStr != "" {
		eventTypes = []protocol.EventType{protocol.EventType(eventTypeStr)}
	}

	// 为每种事件类型创建订阅
	for _, eventType := range eventTypes {
		eventChan := s.eventBus.Subscribe(eventType, nil) // nil filter means accept all events

		// 启动goroutine监听事件并发送到WebSocket
		go func(ch chan protocol.Event, et protocol.EventType) {
			for {
				select {
				case event, ok := <-ch:
					if !ok {
						return
					}

					// 序列化事件为JSON
					data, err := sonic.Marshal(event)
					if err != nil {
						s.logger.Error("Failed to marshal event", zap.Error(err))
						continue
					}

					// 发送到WebSocket连接
					if err := wsConn.SendMessage(data); err != nil {
						s.logger.Error("Failed to send event to WebSocket",
							zap.String("conn_id", wsConn.ID),
							zap.Error(err))
						// 连接可能已断开，取消订阅
						s.eventBus.Unsubscribe(et, ch)
						return
					}

				case <-wsConn.ctx.Done():
					// 连接关闭，取消订阅
					s.eventBus.Unsubscribe(et, ch)
					return
				}
			}
		}(eventChan, eventType)
	}

	s.logger.Info("WebSocket event subscription established",
		zap.String("conn_id", wsConn.ID),
		zap.String("subscriber_id", subscriberID))
}