package connect

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"strings"
	"sync"
	"time"

	"FireLeave_tool/logger"
	"github.com/gorilla/websocket"
)

// Global variables
var (
	wsClient         *WSClient
	wsMutex          sync.RWMutex
	isConnecting     bool
	wsURL            = "ws://172.17.0.1:18080/ws" // Updated to specified address
	deviceDataMutex  sync.Mutex
	ConfigUpdateChan chan DeviceData
	currentServiceID string // New: current service's server_id
)

type PublishParams struct {
	Topic   string          `json:"topic"`
	Data    json.RawMessage `json:"data,omitempty"`
	Content json.RawMessage `json:"content,omitempty"`
}

type InferenceHeartbeat struct {
	DeviceUUID  string  `json:"device_uuid"`
	PersonCount int     `json:"person_count"`
	Temperature float64 `json:"temperature,omitempty"`
	Timestamp   int64   `json:"timestamp"` // 上报时间戳
}

func GetWSClient() *WSClient {
	wsMutex.RLock()
	defer wsMutex.RUnlock()
	return wsClient
}

func (c *WSClient) IsConnected() bool {
	c.mutex.Lock()
	defer c.mutex.Unlock()
	return c.connected
}

const (
	serviceConfigFile = "/usr/local/etc/service.conf"
)

// DeviceData struct
type DeviceData struct {
	DeviceUUID           string      `json:"device_uuid"`
	TaskID               string      `json:"task_id"`
	CameraRTSP           string      `json:"camera_rtsp"`
	CameraIP             string      `json:"camera_ip"`
	Confidence           int         `json:"confidence"`
	DetectArea           []Area      `json:"detect_area"`
	DetectAreaStr        string      `json:"detect_area_str,omitempty"`
	PersonCount          int         `json:"person_count"`
	DetectionTime        json.Number `json:"detection_time"` // Using json.Number
	AlarmTime            json.Number `json:"alarm_time"`     // Using json.Number
	TemperatureThreshold float64     `json:"temperature_threshold"`
	Temperature          float64     `json:"temperature"`
	UploadURL            string      `json:"upload_url"`
	WSConn               *websocket.Conn
	CameraChannel        int    `json:"camera_channel"`
	LastAlarmTime        int64  `json:"-"` // Last alarm time
	AlarmPauseUntil      int64  `json:"-"` // Pause alarm untilw
	HostUUID             string `json:"host_uuid"`
	Address              string `json:"address"`
}

type InferenceParams struct {
	DeviceUUID    string `json:"device_uuid"`
	CameraRTSP    string `json:"camera_rtsp"`
	CameraChannel int    `json:"camera_channel"`
	Confidence    int    `json:"confidence"`
	DetectArea    string `json:"detect_area"` // String format detection area
	Port          int    `json:"port"`        // HTTP server port
}

type Area struct {
	ID  int     `json:"id"`
	Pts []Point `json:"pts"`
}

type Point struct {
	X float64 `json:"x"`
	Y float64 `json:"y"`
}

// WSMessage struct
type WSMessage struct {
	ID     int64           `json:"id,omitempty"`
	Method string          `json:"method"`
	Params json.RawMessage `json:"params,omitempty"`
	Result json.RawMessage `json:"result,omitempty"` // Modified: string -> json.RawMessage
	Error  *WSError        `json:"error,omitempty"`
}

type WSError struct {
	Code    int    `json:"code"`
	Message string `json:"message"`
}

type RegisterParams struct {
	ContainerName string                 `json:"container_name,omitempty"`
	ServiceID     string                 `json:"service_id,omitempty"`
	MetaData      map[string]interface{} `json:"meta_data,omitempty"` // New: metadata field
}

type SubscribeParams struct {
	Topic string `json:"topic"`
}

type WSClient struct {
	Conn          *websocket.Conn
	url           string
	serviceID     string
	serverID      string
	connected     bool
	mutex         sync.Mutex
	messageID     int64
	callbacks     map[int64]chan *WSMessage
	subscribers   map[string]func([]byte)
	closeChan     chan struct{}
	reconnectFlag bool
}

// NewWSClient creates WebSocket client
func NewWSClient(url string) (*WSClient, error) {
	conn, _, err := websocket.DefaultDialer.Dial(url, nil)
	if err != nil {
		return nil, err
	}

	client := &WSClient{
		Conn:          conn,
		url:           url,
		connected:     true,
		messageID:     1,
		callbacks:     make(map[int64]chan *WSMessage),
		subscribers:   make(map[string]func([]byte)),
		closeChan:     make(chan struct{}),
		reconnectFlag: true,
	}

	go client.readLoop()
	go client.heartbeatLoop()
	return client, nil
}

func (c *WSClient) connect() error {
	conn, _, err := websocket.DefaultDialer.Dial(c.url, nil)
	if err != nil {
		return err
	}
	c.Conn = conn
	c.connected = true
	go c.readLoop()
	go c.heartbeatLoop()
	return nil
}

// InitWSChannel initializes WebSocket
func InitWSChannel() error {
	wsMutex.Lock()
	defer wsMutex.Unlock()

	if wsClient != nil && wsClient.connected {
		logger.Logger.Printf("WebSocket connection already exists")
		return nil
	}

	if isConnecting {
		logger.Logger.Printf("WebSocket connection is being established")
		return fmt.Errorf("WebSocket connection is being established")
	}

	isConnecting = true
	defer func() { isConnecting = false }()

	logger.Logger.Printf("Starting WebSocket connection initialization: %s", wsURL)

	// Connect WebSocket asynchronously to avoid blocking
	go func() {
		client, err := NewWSClient(wsURL)
		if err != nil {
			logger.Logger.Printf("Failed to create WebSocket client: %v", err)
			return
		}

		if ConfigUpdateChan == nil {
			ConfigUpdateChan = make(chan DeviceData, 100)
		}

		// Note: No longer calling LoadDeviceData() here to avoid duplicate loading
		wsClient = client
		logger.Logger.Printf("WebSocket connection initialized successfully (asynchronous)")
	}()

	return nil
}

// New: function to generate server_id
func generateServiceID() string {
	return fmt.Sprintf("fireleave-service-%d", time.Now().UnixNano())
}

// New: set current server_id
//func SetServerID(serverID string) {
//	currentServerID = serverID
//}

func GetServiceID() string {
	if currentServiceID == "" {
		currentServiceID = generateServiceID()
	}
	return currentServiceID
}

// RegisterService service registration - modified: now requires providing own server_id
func RegisterService(containerName string) (string, error) {
	if wsClient == nil {
		return "", fmt.Errorf("WebSocket client not initialized")
	}

	serviceID := GetServiceID()

	params := RegisterParams{
		ContainerName: containerName,
		ServiceID:     serviceID,
		MetaData: map[string]interface{}{ // Add metadata
			"version": "1.0",
			"type":    "fire_leave",
		},
	}
	logger.Logger.Printf("Starting service registration: ContainerName=%s, ServiceID=%s", containerName, serviceID)
	response, err := wsClient.sendRequest("register", params, true)
	if err != nil {
		logger.Logger.Printf("Service registration failed: %v", err)
		return "", err
	}
	if response.Error != nil {
		logger.Logger.Printf("Service registration error: Code=%d, Message=%s", response.Error.Code, response.Error.Message)
		return "", fmt.Errorf("Service registration error: %s", response.Error.Message)
	}

	// Parse response
	var resultStr string
	if err := json.Unmarshal(response.Result, &resultStr); err != nil {
		logger.Logger.Printf("Failed to parse service registration response: %v, Raw response: %s", err, string(response.Result))
		return "", fmt.Errorf("Failed to parse service registration response: %v", err)
	}

	if resultStr != "ok" {
		logger.Logger.Printf("Service registration failed: Expected result 'ok', got '%s'", resultStr)
		return "", fmt.Errorf("Service registration failed: Server returned abnormal response")
	}

	wsClient.serviceID = serviceID
	logger.Logger.Printf("Service registration successful: ServiceID=%s", serviceID)
	return serviceID, nil
}

// SubscribeTopic topic subscription
func SubscribeTopic(topic string, callback func([]byte)) error {
	if wsClient == nil {
		return fmt.Errorf("WebSocket client not initialized")
	}
	params := SubscribeParams{
		Topic: topic,
	}
	logger.Logger.Printf("Starting topic subscription: Topic=%s", topic)
	response, err := wsClient.sendRequest("subscribe", params, true)
	if err != nil {
		logger.Logger.Printf("Topic subscription failed: %v", err)
		return err
	}
	if response.Error != nil {
		logger.Logger.Printf("Topic subscription error: Code=%d, Message=%s", response.Error.Code, response.Error.Message)
		return fmt.Errorf("Topic subscription error: %s", response.Error.Message)
	}
	wsClient.mutex.Lock()
	wsClient.subscribers[topic] = callback
	wsClient.mutex.Unlock()
	logger.Logger.Printf("Topic subscription successful: Topic=%s", topic)
	return nil
}

func (c *WSClient) SendRawMessage(message interface{}) error {
	c.mutex.Lock()
	defer c.mutex.Unlock()
	if !c.connected {
		return fmt.Errorf("WebSocket connection disconnected")
	}
	messageData, err := json.Marshal(message)
	if err != nil {
		return fmt.Errorf("Message serialization failed: %v", err)
	}
	logger.Logger.Printf("Sending WebSocket message: %s", string(messageData))
	err = c.Conn.WriteMessage(websocket.TextMessage, messageData)
	if err != nil {
		logger.Logger.Printf("WebSocket message sending failed: %v", err)
		c.connected = false
		go c.reconnect()
		return fmt.Errorf("Message sending failed: %v", err)
	}
	return nil
}

// sendRequest sends request
func (c *WSClient) sendRequest(method string, params interface{}, waitResponse bool) (*WSMessage, error) {
	c.mutex.Lock()
	id := c.messageID
	c.messageID++
	c.mutex.Unlock()

	message := WSMessage{
		ID:     id,
		Method: method,
	}
	if params != nil {
		paramsData, err := json.Marshal(params)
		if err != nil {
			return nil, fmt.Errorf("Parameter serialization failed: %v", err)
		}
		message.Params = paramsData
	}

	if waitResponse {
		callback := make(chan *WSMessage, 1)
		c.mutex.Lock()
		c.callbacks[id] = callback
		c.mutex.Unlock()

		defer func() {
			c.mutex.Lock()
			delete(c.callbacks, id)
			c.mutex.Unlock()
			logger.Logger.Printf("Cleaning up callback channel: ID=%d", id)
		}()

		if err := c.SendRawMessage(message); err != nil {
			return nil, err
		}

		logger.Logger.Printf("Waiting for response: ID=%d", id)
		select {
		case response := <-callback:
			logger.Logger.Printf("Received response: ID=%d", id)
			return response, nil
		case <-time.After(30 * time.Second):
			logger.Logger.Printf("Response timeout: ID=%d", id)
			return nil, fmt.Errorf("Response timeout")
		case <-c.closeChan:
			logger.Logger.Printf("Connection closed, stopping response wait: ID=%d", id)
			return nil, fmt.Errorf("Connection closed")
		}
	}
	return nil, c.SendRawMessage(message)
}

// readLoop message reading loop
func (c *WSClient) readLoop() {
	logger.Logger.Printf("Starting WebSocket message reading loop")
	defer func() {
		if r := recover(); r != nil {
			logger.Logger.Printf("readLoop panic: %v", r)
		}
		// Important: do not close(closeChan)!
		logger.Logger.Printf("WebSocket read loop exited, connection marked as disconnected")
	}()

	for {
		_, messageData, err := c.Conn.ReadMessage()
		if err != nil {
			logger.Logger.Printf("WebSocket message reading failed: %v", err)
			c.mutex.Lock()
			c.connected = false
			c.mutex.Unlock()
			go c.reconnect() // Trigger reconnection
			return
		}

		if string(messageData) == "pong" {
			logger.Logger.Printf("Received pong response")
			continue
		}

		logger.Logger.Printf("Received WebSocket message: %s", string(messageData))

		var message WSMessage
		if err := json.Unmarshal(messageData, &message); err != nil {
			logger.Logger.Printf("WebSocket message parsing failed: %v", err)
			continue
		}

		if message.ID > 0 {
			c.mutex.Lock()
			if callback, exists := c.callbacks[message.ID]; exists {
				select {
				case callback <- &message:
					logger.Logger.Printf("Successfully sent message to callback channel: ID=%d", message.ID)
				default:
					logger.Logger.Printf("Callback channel full, discarding message: ID=%d", message.ID)
				}
			}
			c.mutex.Unlock()
		}

		if message.Method == "publish" {
			c.handlePublishMessage(message)
		}
	}
}

// handlePublishMessage handles publish messages
func (c *WSClient) handlePublishMessage(message WSMessage) {
	logger.Logger.Printf("Processing publish message")
	var publishParams PublishParams
	if err := json.Unmarshal(message.Params, &publishParams); err != nil {
		logger.Logger.Printf("Failed to parse publish message parameters: %v", err)
		return
	}
	logger.Logger.Printf("WebSocket 收到 publish 消息 → Topic: %s | 原始数据: %s",
		publishParams.Topic, string(publishParams.Data))

	if publishParams.Topic != "" {
		c.mutex.Lock()
		callback, exists := c.subscribers[publishParams.Topic]
		c.mutex.Unlock()
		if exists && callback != nil {
			callback(message.Params)
		}
	}

	if publishParams.Data != nil {
		var deviceData DeviceData
		if err := json.Unmarshal(publishParams.Data, &deviceData); err != nil {
			logger.Logger.Printf("Failed to parse DeviceData: %v", err)
			return
		}

		// Check if DeviceUUID is valid
		if deviceData.DeviceUUID == "" {
			logger.Logger.Printf("Invalid DeviceData: DeviceUUID is empty, ignoring")
			return
		}

		logger.Logger.Printf("Received valid DeviceData: DeviceUUID=%s", deviceData.DeviceUUID)

		// 1. Save original configuration to service config file (using SaveSingleServiceConfig)
		if err := SaveSingleServiceConfig(deviceData); err != nil {
			logger.Logger.Printf("Failed to save service configuration: %v", err)
		}

		// 2. Process data and save to device data file
		processedData := ProcessDeviceDataForInference(deviceData)
		if err := UpdateDeviceData(processedData); err != nil {
			logger.Logger.Printf("Failed to update DeviceData: %v", err)
			return
		}

		select {
		case ConfigUpdateChan <- processedData:
			logger.Logger.Printf("New DeviceData sent to config update channel: DeviceUUID=%s", processedData.DeviceUUID)
		default:
			logger.Logger.Printf("Config update channel full, discarding message")
		}

	}
}

// heartbeatLoop heartbeat loop - fixed version
func (c *WSClient) heartbeatLoop() {
	logger.Logger.Printf("Starting WebSocket heartbeat loop")
	ticker := time.NewTicker(25 * time.Second)
	defer ticker.Stop()

	for {
		select {
		case <-ticker.C:
			c.mutex.Lock()
			connected := c.connected
			conn := c.Conn
			c.mutex.Unlock()

			if connected && conn != nil {
				err := conn.WriteMessage(websocket.PingMessage, []byte{})
				if err != nil {
					logger.Logger.Printf("Failed to send ping: %v", err)
					c.mutex.Lock()
					c.connected = false
					c.mutex.Unlock()
					go c.reconnect()
				} else {
					logger.Logger.Printf("Ping sent successfully")
				}
			}
		case <-c.closeChan:
			logger.Logger.Printf("Heartbeat loop received close signal, exiting")
			ticker.Stop() // Explicitly stop ticker
			return
		}
	}
}

func (c *WSClient) reRegisterAndResubscribe() {
	// 1. 等待连接稳定
	time.Sleep(1 * time.Second)

	// 2. 重新注册
	containerName := "fireleave-container"
	serviceID, err := RegisterService(containerName)
	if err != nil {
		logger.Logger.Printf("Failed to re-register service after reconnect: %v", err)
		return
	}
	logger.Logger.Printf("Re-registration successful: ServiceID=%s", serviceID)

	// 3. 重新订阅
	for topic, callback := range c.subscribers {
		if err := SubscribeTopic(topic, callback); err != nil {
			logger.Logger.Printf("Failed to re-subscribe topic %s: %v", topic, err)
		} else {
			logger.Logger.Printf("Re-subscribed to topic: %s", topic)
		}
	}
}

// connect/wschannel.go → reconnect complete fix
func (c *WSClient) reconnect() {
	if !c.reconnectFlag {
		return
	}

	for i := 0; i < 12; i++ {
		delay := time.Duration(1<<uint(i)) * time.Second
		if delay > 30*time.Second {
			delay = 30 * time.Second
		}
		time.Sleep(delay)

		conn, _, err := websocket.DefaultDialer.Dial(c.url, nil)
		if err != nil {
			logger.Logger.Printf("Reconnection attempt %d/12 failed: %v", i+1, err)
			continue
		}

		c.mutex.Lock()
		c.Conn = conn
		c.connected = true
		c.mutex.Unlock()

		logger.Logger.Printf("WebSocket reconnection successful!")

		// 关键：重连后必须先 register！
		go c.reRegisterAndResubscribe()

		// 重启读写循环
		go c.readLoop()
		go c.heartbeatLoop()
		return
	}

	logger.Logger.Printf("Reconnection failed after 12 attempts")
	c.reconnectFlag = false
}
func (d *DeviceData) ToInferenceParams(port int) InferenceParams {
	return InferenceParams{
		DeviceUUID:    d.DeviceUUID,
		CameraRTSP:    d.CameraRTSP,
		CameraChannel: d.CameraChannel,
		Confidence:    d.Confidence,
		DetectArea:    ProcessDetectAreaForInference(d.DetectArea),
		Port:          port,
	}
}

// SaveServiceConfig saves multiple device configurations to service config file
func SaveServiceConfig(deviceDataList []DeviceData) error {
	configData, err := json.MarshalIndent(deviceDataList, "", "  ")
	if err != nil {
		logger.Logger.Printf("Failed to serialize service configuration: %v", err)
		return err
	}

	if err := os.WriteFile(serviceConfigFile, configData, 0644); err != nil {
		logger.Logger.Printf("Failed to write service config file: %v", err)
		return err
	}

	logger.Logger.Printf("Service configuration saved to: %s, %d devices", serviceConfigFile, len(deviceDataList))
	return nil
}

// SaveSingleServiceConfig saves single device configuration (compatible with existing calls)
func SaveSingleServiceConfig(deviceData DeviceData) error {
	// First read existing configuration
	existingConfigs, err := LoadServiceConfig()
	if err != nil {
		// If reading fails, create new configuration list
		existingConfigs = []DeviceData{deviceData}
	} else {
		// Find if configuration with same DeviceUUID already exists
		found := false
		for i, existing := range existingConfigs {
			if existing.DeviceUUID == deviceData.DeviceUUID {
				existingConfigs[i] = deviceData
				found = true
				break
			}
		}
		// If not exists, add to list
		if !found {
			existingConfigs = append(existingConfigs, deviceData)
		}
	}

	return SaveServiceConfig(existingConfigs)
}

// LoadServiceConfig loads multiple device data from service config file
func LoadServiceConfig() ([]DeviceData, error) {
	if _, err := os.Stat(serviceConfigFile); os.IsNotExist(err) {
		logger.Logger.Printf("Service config file does not exist: %s", serviceConfigFile)
		return nil, fmt.Errorf("service config file does not exist")
	}

	data, err := os.ReadFile(serviceConfigFile)
	if err != nil {
		logger.Logger.Printf("Failed to read service config file: %v", err)
		return nil, err
	}

	// Check if file content is empty
	if len(data) == 0 {
		logger.Logger.Printf("Service config file is empty")
		return nil, fmt.Errorf("service config file is empty")
	}

	// Parse as DeviceData array
	var deviceDataList []DeviceData
	if err := json.Unmarshal(data, &deviceDataList); err != nil {
		logger.Logger.Printf("Failed to parse service config file: %v", err)
		return nil, err
	}

	// Filter out configurations with empty DeviceUUID
	var validDeviceDataList []DeviceData
	for _, deviceData := range deviceDataList {
		if deviceData.DeviceUUID != "" {
			validDeviceDataList = append(validDeviceDataList, deviceData)
		}
	}
	const FixedUploadURL = "http://192.168.80.168/api/v1/upload/video"
	for i := range validDeviceDataList {
		if validDeviceDataList[i].UploadURL == "" {
			validDeviceDataList[i].UploadURL = FixedUploadURL
			logger.Logger.Printf("Auto-completed UploadURL: %s (DeviceUUID=%s)",
				FixedUploadURL, validDeviceDataList[i].DeviceUUID)
		}
	}
	if len(validDeviceDataList) == 0 {
		logger.Logger.Printf("No valid device configurations found in service config file")
		return nil, fmt.Errorf("no valid device configurations")
	}

	logger.Logger.Printf("Loaded %d device configurations from service config file", len(validDeviceDataList))
	return validDeviceDataList, nil

}

// ProcessDetectAreaForInference processes detection area data, converts to format required by inference program
func ProcessDetectAreaForInference(areas []Area) string {
	if len(areas) == 0 {
		return ""
	}

	// Only take the first detection area
	area := areas[0]
	var points []string

	for _, point := range area.Pts {
		// Directly round, remove decimals
		x := int(point.X)
		y := int(point.Y)
		points = append(points, fmt.Sprintf("%d,%d", x, y))
	}

	return strings.Join(points, ",")
}

func ProcessDeviceDataForInference(data DeviceData) DeviceData {
	// Create a copy, only process fields that need conversion
	processed := data
	processed.DetectAreaStr = ProcessDetectAreaForInference(data.DetectArea)
	return processed
}

func (c *WSClient) SendAsync(message interface{}) {
	go func() {
		ctx, cancel := context.WithTimeout(context.Background(), 8*time.Second)
		defer cancel()

		done := make(chan error, 1)
		go func() {
			done <- c.SendRawMessage(message)
		}()

		select {
		case err := <-done:
			if err != nil {
				logger.Logger.Printf("Asynchronous reporting failed: %v", err)
			} else {
				logger.Logger.Printf("Asynchronous reporting successful")
			}
		case <-ctx.Done():
			logger.Logger.Printf("Asynchronous reporting timeout (8 seconds no response), continuing business process")
		}
	}()
}