package controller

import (
	"context"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"os"
	"sync"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/go-redis/redis/v8"
	"github.com/gorilla/websocket"
	"xk-websocket/models" // 替换为实际路径
	"xk-websocket/utils"  // 导入新的utils包
)

var upgrader = websocket.Upgrader{
	ReadBufferSize:  1024,
	WriteBufferSize: 1024,
	CheckOrigin: func(r *http.Request) bool {
		return true
	},
}

// WebSocketController WebSocket控制器结构体
type WebSocketController struct {
	Clients    map[string]*websocket.Conn
	ClientsMux sync.RWMutex
	RedisCli   *redis.Client
	NodeID     string
	Port       string
	RedisCtx   context.Context
	Logger     *log.Logger
}

func NewWebSocketController() *WebSocketController {
	return &WebSocketController{
		Clients:  make(map[string]*websocket.Conn),
		RedisCtx: context.Background(),
	}
}

// ConfigureSystem 配置系统参数
func (c *WebSocketController) ConfigureSystem() {
	c.NodeID = utils.GetEnv("NODE_ID", "local")
	c.Port = utils.GetEnv("PORT", "12080")
	log.SetPrefix(fmt.Sprintf("[Node:%s] ", c.NodeID))
	log.SetFlags(log.LstdFlags | log.Lmicroseconds)
	c.configureLogger()
}

// 配置日志记录器
func (c *WebSocketController) configureLogger() {
	logDir := utils.GetEnv("LOG_DIR", "./logs")
	if err := os.MkdirAll(logDir, 0755); err != nil {
		log.Fatalf("❌❌ 创建日志目录失败: %v", err)
	}

	logFreq := utils.GetEnv("LOG_ROTATE_FREQ", "daily")
	if c.Logger == nil {
		c.Logger = log.New(os.Stdout, "", log.LstdFlags|log.Lmicroseconds)
	}

	c.Logger.SetPrefix(fmt.Sprintf("[Node:%s] ", c.NodeID))
	log.SetOutput(c.getLogWriter(logDir, logFreq))
}

// 获取日志文件写入器
func (c *WebSocketController) getLogWriter(logDir, freq string) *utils.DailyFileWriter {
	return utils.NewDailyFileWriter(logDir, freq, c.Logger, c.NodeID)
}

// InitRedisClient 初始化Redis客户端
func (c *WebSocketController) InitRedisClient() {
	redisAddr := utils.GetEnv("REDIS_ADDR", "localhost:6379")
	redisPassword := utils.GetEnv("REDIS_PASSWORD", "")
	c.RedisCli = redis.NewClient(&redis.Options{
		Addr:     redisAddr,
		Password: redisPassword,
		DB:       0,
	})

	if err := c.checkRedisConnection(); err != nil {
		log.Fatalf("❌❌ Redis连接失败: %v", err)
	}
}

// 检查Redis连接
func (c *WebSocketController) checkRedisConnection() error {
	_, err := c.RedisCli.Ping(c.RedisCtx).Result()
	return err
}

// PrintStartupInfo 打印启动信息
func (c *WebSocketController) PrintStartupInfo() {
	hostname, _ := os.Hostname()
	log.Printf("🚀🚀 WebSocket服务启动: NodeID=%s", c.NodeID)
	log.Printf("🌐🌐 监听端口: %s", c.Port)
	log.Printf("📡📡 Redis地址: %s", utils.GetEnv("REDIS_ADDR", "localhost:6379"))
	log.Printf("💻💻 主机: %s", hostname)
	log.Printf("🕒🕒🕒 启动时间: %s", time.Now().Format("2006-01-02 15:04:05"))
	log.Printf("🔔🔔 支持消息类型: \n  0:文本\n  1:图片\n  2:音频\n  3:视频\n  4:处方\n  5:病例\n  6:视频通话")
	log.Printf("🔑🔑 用户绑定键: \n  %s\n  %s", models.ClientUserKey, models.UserClientKey)
	log.Printf("📬📬 新增接口: POST /send-to-user (直接通过用户ID发送消息)")
	log.Println("🔗🔗 等待客户端连接...")
}

// HealthHandler 健康检查处理器
func (c *WebSocketController) HealthHandler(ctx *gin.Context) {
	ctx.JSON(http.StatusOK, gin.H{
		"status": "ok",
		"node":   c.NodeID,
		"time":   time.Now().Format(time.RFC3339),
	})
}

// HandleWebSocket WebSocket连接处理器
func (c *WebSocketController) HandleWebSocket(ctx *gin.Context) {
	start := time.Now()
	clientIP := ctx.ClientIP()
	log.Printf("👤👤 客户端连接中: IP=%s", clientIP)

	conn, err := upgrader.Upgrade(ctx.Writer, ctx.Request, nil)
	if err != nil {
		log.Printf("⚠️ WebSocket升级失败: %v | ClientIP=%s", err, clientIP)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "无法升级为WebSocket连接"})
		return
	}
	defer conn.Close()

	clientID := utils.GenerateClientID(c.NodeID)
	log.Printf("✅ 客户端已连接: \n  ClientID=%s \n  IP=%s \n  Duration=%s",
		clientID, clientIP, time.Since(start))

	c.addClient(clientID, conn)
	defer c.removeClient(clientID)

	if err := conn.WriteJSON(gin.H{"clientId": clientID}); err != nil {
		log.Printf("⚠️ 发送客户端ID失败: %v | ClientID=%s", err, clientID)
		return
	}

	conn.SetPongHandler(func(string) error {
		conn.SetReadDeadline(time.Now().Add(60 * time.Second))
		return nil
	})

	for {
		messageType, message, err := conn.ReadMessage()
		if err != nil {
			if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway) {
				log.Printf("❌❌ 连接意外断开: %v | ClientID=%s", err, clientID)
			} else {
				log.Printf("⚠️ 连接正常关闭: ClientID=%s", clientID)
			}
			break
		}

		if messageType == websocket.TextMessage {
			go c.handleClientMessage(clientID, message)
		}
	}
}

// 处理客户端消息
func (c *WebSocketController) handleClientMessage(senderID string, message []byte) {
	log.Printf("📥📥 收到客户端消息: \n  SenderID=%s \n  Size=%d bytes", senderID, len(message))

	var payload models.SendMessagePayload
	if err := json.Unmarshal(message, &payload); err == nil && payload.RequestType != "" {
		log.Printf("📦📦 解析JSON消息成功: Type=%s", payload.RequestType)

		if payload.RequestType == "bind" && payload.SenderUserID != "" {
			log.Printf("🔗🔗 处理绑定请求: \n  ClientID=%s \n  UserID=%s", senderID, payload.SenderUserID)
			if err := c.bindClientToUser(senderID, payload.SenderUserID); err != nil {
				log.Printf("❌❌ 绑定失败: %v", err)
			} else {
				log.Printf("✅ 绑定成功: \n  ClientID=%s \n  UserID=%s", senderID, payload.SenderUserID)
			}
			return
		}

		if payload.RequestType == "send_message" {
			if payload.TargetClientID != "" {
				log.Printf("📨📨 处理客户端发起的发送请求: \n  TargetID=%s \n  MsgType=%d",
					payload.TargetClientID, payload.MessageType)

				clientMsg := models.ClientReceivedMessage{
					SenderID:       senderID,
					ReceiverID:     payload.TargetClientID,
					SenderUserID:   payload.SenderUserID,
					ReceiverUserID: payload.ReceiverUserID,
					MessageType:    payload.MessageType,
					Content:        payload.MessageContent,
					SendTime:       time.Now().Format(time.RFC3339),
				}

				c.sendMessageToClient(payload.TargetClientID, clientMsg)
				return
			}

			if payload.ReceiverUserID != "" {
				log.Printf("📨📨 处理客户端发起的用户发送请求: \n  ReceiverUserID=%s \n  MsgType=%d",
					payload.ReceiverUserID, payload.MessageType)

				clientMsg := models.ClientReceivedMessage{
					SenderID:       senderID,
					ReceiverID:     "",
					SenderUserID:   payload.SenderUserID,
					ReceiverUserID: payload.ReceiverUserID,
					MessageType:    payload.MessageType,
					Content:        payload.MessageContent,
					SendTime:       time.Now().Format(time.RFC3339),
				}

				c.sendMessageToUser(payload.ReceiverUserID, clientMsg)
				return
			}
		}
	}

	var clientMsg models.ClientReceivedMessage
	if err := json.Unmarshal(message, &clientMsg); err == nil && clientMsg.ReceiverID != "" {
		log.Printf("📨📨 处理客户端封装消息: \n  TargetID=%s \n  MsgType=%d",
			clientMsg.ReceiverID, clientMsg.MessageType)

		clientMsg.SenderID = senderID
		c.sendMessageToClient(clientMsg.ReceiverID, clientMsg)
		return
	}

	log.Printf("⚠️ 无法识别的消息格式: \n  Size=%d bytes \n  Message=%s", len(message), string(message))
}

// SendMessageHandler API消息发送处理器
func (c *WebSocketController) SendMessageHandler(ctx *gin.Context) {
	start := time.Now()

	var payload models.SendMessagePayload
	if err := ctx.ShouldBindJSON(&payload); err != nil {
		log.Printf("⚠️ 无效的JSON请求格式: %v", err)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "无效的JSON格式"})
		return
	}

	if payload.RequestType == "" || (payload.TargetClientID == "" && payload.ReceiverUserID == "") ||
		payload.SenderUserID == "" || payload.ReceiverUserID == "" {
		log.Printf("⚠️ 缺少必要参数: \n  request_type=%s \n  target_client_id=%s \n  receiver_user_id=%s \n  sender_user_id=%s \n  receiver_user_id=%s",
			payload.RequestType, payload.TargetClientID, payload.ReceiverUserID, payload.SenderUserID, payload.ReceiverUserID)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "缺少必要参数"})
		return
	}

	if payload.RequestType == "send_message" {
		log.Printf("📤📤 处理API发送请求: \n  SenderUser=%s \n  MsgType=%d",
			payload.SenderUserID, payload.MessageType)

		clientMsg := models.ClientReceivedMessage{
			SenderID:       "system",
			ReceiverID:     payload.TargetClientID,
			SenderUserID:   payload.SenderUserID,
			ReceiverUserID: payload.ReceiverUserID,
			MessageType:    payload.MessageType,
			Content:        payload.MessageContent,
			SendTime:       time.Now().Format(time.RFC3339),
		}

		var result string
		var sendErr error

		if payload.TargetClientID != "" {
			log.Printf("🎯🎯 目标类型: ClientID | Target=%s", payload.TargetClientID)
			sendErr = c.sendMessageToClient(payload.TargetClientID, clientMsg)
			result = fmt.Sprintf("消息已发送到ClientID: %s", payload.TargetClientID)
		} else if payload.ReceiverUserID != "" {
			log.Printf("🎯🎯 目标类型: UserID | ReceiverUser=%s", payload.ReceiverUserID)
			sendErr = c.sendMessageToUser(payload.ReceiverUserID, clientMsg)
			result = fmt.Sprintf("消息已发送到UserID: %s", payload.ReceiverUserID)
		} else {
			ctx.JSON(http.StatusBadRequest, gin.H{"error": "必须指定目标客户端ID或用户ID"})
			return
		}

		if sendErr != nil {
			ctx.JSON(http.StatusInternalServerError, gin.H{"error": sendErr.Error()})
			return
		}

		ctx.JSON(http.StatusOK, gin.H{"status": "success", "message": result})
		log.Printf("✅ API请求完成: Duration=%s", time.Since(start))
		return
	}

	ctx.JSON(http.StatusBadRequest, gin.H{"error": "不支持的request_type"})
}

// 用户绑定处理器
func (c *WebSocketController) BindHandler(ctx *gin.Context) {
	start := time.Now()

	var req models.BindRequest
	if err := ctx.ShouldBindJSON(&req); err != nil {
		log.Printf("⚠️ 无效的绑定请求格式: %v", err)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "无效的JSON格式"})
		return
	}

	if req.UserID == "" || req.ClientID == "" {
		log.Printf("⚠️ 缺少必要参数: \n  user_id=%s \n  client_id=%s", req.UserID, req.ClientID)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "user_id和client_id不能为空"})
		return
	}

	log.Printf("🔗🔗 处理用户绑定请求: \n  UserID=%s \n  ClientID=%s", req.UserID, req.ClientID)

	if err := c.bindClientToUser(req.ClientID, req.UserID); err != nil {
		log.Printf("❌❌ 绑定失败: %v", err)
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, gin.H{
		"status":  "success",
		"message": fmt.Sprintf("绑定成功: ClientID %s -> UserID %s", req.ClientID, req.UserID),
	})

	log.Printf("✅ 绑定请求完成: \n  UserID=%s \n  ClientID=%s \n  Duration=%s",
		req.UserID, req.ClientID, time.Since(start))
}

// 通过用户ID发送消息处理器
func (c *WebSocketController) SendToUserHandler(ctx *gin.Context) {
	start := time.Now()

	var payload models.SendToUserPayload
	if err := ctx.ShouldBindJSON(&payload); err != nil {
		log.Printf("⚠️ 无效的JSON请求格式: %v", err)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "无效的JSON格式"})
		return
	}

	if payload.ReceiverUserID == "" || payload.SenderUserID == "" {
		log.Printf("⚠️ 缺少必要参数: \n  receiver_user_id=%s \n  sender_user_id=%s",
			payload.ReceiverUserID, payload.SenderUserID)
		ctx.JSON(http.StatusBadRequest, gin.H{"error": "缺少接收方或发送方用户ID"})
		return
	}

	log.Printf("📤📤 处理API用户发送请求: \n  SenderUser=%s → ReceiverUser=%s \n  MsgType=%d",
		payload.SenderUserID, payload.ReceiverUserID, payload.MessageType)

	clientMsg := models.ClientReceivedMessage{
		SenderID:       "system",
		ReceiverID:     "",
		SenderUserID:   payload.SenderUserID,
		ReceiverUserID: payload.ReceiverUserID,
		MessageType:    payload.MessageType,
		Content:        payload.MessageContent,
		SendTime:       time.Now().Format(time.RFC3339),
	}

	if err := c.sendMessageToUser(payload.ReceiverUserID, clientMsg); err != nil {
		ctx.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	ctx.JSON(http.StatusOK, gin.H{
		"code":    0,
		"status":  "success",
		"message": fmt.Sprintf("消息已发送至用户 %s", payload.ReceiverUserID),
	})

	log.Printf("✅ API请求完成: Duration=%s", time.Since(start))
}

// 绑定客户端与用户
func (c *WebSocketController) bindClientToUser(clientID, userID string) error {
	if err := c.RedisCli.HSet(c.RedisCtx, models.ClientUserKey, clientID, userID).Err(); err != nil {
		return fmt.Errorf("保存client-user映射失败: %w", err)
	}

	userClientKey := fmt.Sprintf("%s:%s", models.UserClientKey, userID)
	if err := c.RedisCli.SAdd(c.RedisCtx, userClientKey, clientID).Err(); err != nil {
		return fmt.Errorf("保存user-client映射失败: %w", err)
	}

	expiration := 24 * time.Hour
	if err := c.RedisCli.Expire(c.RedisCtx, userClientKey, expiration).Err(); err != nil {
		log.Printf("⚠️ 设置过期时间失败: %v", err)
	}

	log.Printf("🔗🔗 用户绑定成功: \n  ClientID=%s → UserID=%s", clientID, userID)
	return nil
}

// 通过用户ID发送消息
func (c *WebSocketController) sendMessageToUser(userID string, msg models.ClientReceivedMessage) error {
	start := time.Now()
	log.Printf("👤👤 通过用户ID发送消息: UserID=%s", userID)

	userClientKey := fmt.Sprintf("%s:%s", models.UserClientKey, userID)
	clientIDs, err := c.RedisCli.SMembers(c.RedisCtx, userClientKey).Result()
	if err != nil {
		return fmt.Errorf("获取用户clientID失败: %w", err)
	}

	if len(clientIDs) == 0 {
		return fmt.Errorf("用户未绑定任何客户端")
	}

	log.Printf("📡📡 找到 %d 个关联的客户端: UserID=%s", len(clientIDs), userID)

	var successCount, failCount int
	var lastError error

	for _, clientID := range clientIDs {
		targetMsg := msg
		targetMsg.ReceiverID = clientID

		if err := c.sendMessageToClient(clientID, targetMsg); err != nil {
			log.Printf("❌❌ 发送消息到客户端失败: \n  ClientID=%s \n  %v", clientID, err)
			failCount++
			lastError = err
		} else {
			successCount++
		}
	}

	log.Printf("📬📬 消息发送完成: \n  成功 %d \n  失败 %d \n  UserID=%s \n  Duration=%s",
		successCount, failCount, userID, time.Since(start))

	if failCount > 0 {
		return fmt.Errorf("部分消息发送失败，最后错误: %w", lastError)
	}
	return nil
}

// 发送消息给客户端
func (c *WebSocketController) sendMessageToClient(clientID string, msg models.ClientReceivedMessage) error {
	start := time.Now()

	msgJSON, err := json.Marshal(msg)
	if err != nil {
		log.Printf("❌❌ 消息序列化失败: %v", err)
		return fmt.Errorf("内部错误")
	}

	if conn := c.getClient(clientID); conn != nil {
		log.Printf("📤📤 向本地客户端发送消息: \n  ClientID=%s \n  MsgType=%d \n  Size=%d bytes",
			clientID, msg.MessageType, len(msgJSON))

		if err := conn.WriteMessage(websocket.TextMessage, msgJSON); err != nil {
			log.Printf("❌❌ 发送消息失败: %v | ClientID=%s", err, clientID)
			c.removeClient(clientID)
			return fmt.Errorf("发送消息失败")
		}

		log.Printf("✅ 消息成功发送到本地客户端: \n  ClientID=%s \n  Duration=%s",
			clientID, time.Since(start))
		return nil
	}

	log.Printf("🌐🌐 向远程节点转发消息: ClientID=%s", clientID)

	redisMsg := models.RedisMessage{
		SenderNodeID: c.NodeID,
		ClientID:     clientID,
		Message:      string(msgJSON),
	}

	redisMsgJSON, err := json.Marshal(redisMsg)
	if err != nil {
		log.Printf("❌❌ Redis消息序列化失败: %v", err)
		return fmt.Errorf("内部错误")
	}

	if err := c.RedisCli.Publish(c.RedisCtx, "ws_messages", redisMsgJSON).Err(); err != nil {
		log.Printf("❌❌ 发布消息到Redis失败: %v", err)
		return fmt.Errorf("无法转发消息")
	}

	log.Printf("📡📡 消息已转发到Redis: \n  ClientID=%s \n  Size=%d bytes \n  Duration=%s",
		clientID, len(redisMsgJSON), time.Since(start))
	return nil
}

// SubscribeToRedis 订阅Redis消息
func (c *WebSocketController) SubscribeToRedis() {
	pubsub := c.RedisCli.Subscribe(c.RedisCtx, "ws_messages")
	defer pubsub.Close()

	ch := pubsub.Channel()
	log.Println("🔔🔔 开始监听Redis消息...")

	for msg := range ch {
		start := time.Now()
		var redisMsg models.RedisMessage

		if err := json.Unmarshal([]byte(msg.Payload), &redisMsg); err != nil {
			log.Printf("❌❌ 解析Redis消息失败: %v", err)
			continue
		}

		log.Printf("📥📥 收到Redis消息: \n  Sender=%s \n  ClientID=%s \n  Size=%d bytes",
			redisMsg.SenderNodeID, redisMsg.ClientID, len(msg.Payload))

		if redisMsg.SenderNodeID == c.NodeID {
			log.Println("ℹℹ️ 忽略本节点转发的消息")
			continue
		}

		if conn := c.getClient(redisMsg.ClientID); conn != nil {
			if err := conn.WriteMessage(websocket.TextMessage, []byte(redisMsg.Message)); err != nil {
				log.Printf("❌❌ 处理Redis消息失败: %v | ClientID=%s", err, redisMsg.ClientID)
				c.removeClient(redisMsg.ClientID)
				continue
			}

			log.Printf("✅ Redis消息已处理: \n  ClientID=%s \n  Duration=%s",
				redisMsg.ClientID, time.Since(start))
		} else {
			log.Printf("⚠️ 目标客户端不在本节点: ClientID=%s", redisMsg.ClientID)
		}
	}
}

// ========================== 辅助方法 ========================== //

// 添加客户端到映射
func (c *WebSocketController) addClient(clientID string, conn *websocket.Conn) {
	c.ClientsMux.Lock()
	defer c.ClientsMux.Unlock()
	c.Clients[clientID] = conn
	log.Printf("📌📌 添加客户端到连接池: \n  ClientID=%s \n  当前连接数=%d",
		clientID, len(c.Clients))
}

// 从映射中移除客户端
func (c *WebSocketController) removeClient(clientID string) {
	c.ClientsMux.Lock()
	defer c.ClientsMux.Unlock()

	if _, exists := c.Clients[clientID]; !exists {
		return
	}

	delete(c.Clients, clientID)
	log.Printf("🗑🗑️ 从连接池移除客户端: \n  ClientID=%s \n  当前连接数=%d",
		clientID, len(c.Clients))

	if err := c.RedisCli.HDel(c.RedisCtx, models.ClientUserKey, clientID).Err(); err != nil {
		log.Printf("⚠️ 删除client_user_mapping失败: %v", err)
	}
}

// 获取客户端连接
func (c *WebSocketController) getClient(clientID string) *websocket.Conn {
	c.ClientsMux.RLock()
	defer c.ClientsMux.RUnlock()
	return c.Clients[clientID]
}