// Package service 提供各种业务服务功能
package service

import (
	"context"
	"errors"
	"fmt"
	"sync"
	"time"

	"git.huangwc.com/pig/pig-farm-controller/internal/config"
	"git.huangwc.com/pig/pig-farm-controller/internal/logs"
	"git.huangwc.com/pig/pig-farm-controller/internal/model"
	"git.huangwc.com/pig/pig-farm-controller/internal/storage/repository"
	"git.huangwc.com/pig/pig-farm-controller/internal/websocket"
	"github.com/panjf2000/ants/v2"
)

// HeartbeatService 心跳服务，负责管理设备的心跳检测
type HeartbeatService struct {
	// websocketManager WebSocket管理器
	websocketManager *websocket.Manager

	// deviceStatusPool 设备状态池
	deviceStatusPool *DeviceStatusPool

	// deviceRepo 设备仓库
	deviceRepo repository.DeviceRepo

	// logger 日志记录器
	logger *logs.Logger

	// 心跳间隔
	heartbeatInterval time.Duration

	// 手动心跳触发器
	triggerChan chan struct{}

	// ticker 心跳定时器
	ticker *time.Ticker

	// poolSize  线程池大小
	poolSize int

	// pool 线程池
	pool *ants.Pool

	// ctx 上下文
	ctx context.Context

	// cancel 取消函数
	cancel context.CancelFunc
}

// NewHeartbeatService 创建心跳服务实例
func NewHeartbeatService(websocketManager *websocket.Manager, deviceStatusPool *DeviceStatusPool, deviceRepo repository.DeviceRepo, config *config.Config) *HeartbeatService {

	interval := config.GetHeartbeatConfig().Interval
	if interval <= 0 {
		interval = 30 // 默认30秒心跳间隔
	}

	concurrency := config.GetHeartbeatConfig().Concurrency
	if concurrency <= 0 {
		concurrency = 10 // 默认10个并发
	}

	return &HeartbeatService{
		websocketManager:  websocketManager,
		deviceStatusPool:  deviceStatusPool,
		deviceRepo:        deviceRepo,
		logger:            logs.NewLogger(),
		heartbeatInterval: time.Duration(interval) * time.Second,
		poolSize:          concurrency,
		triggerChan:       make(chan struct{}),
	}
}

// Start 启动心跳服务
func (hs *HeartbeatService) Start() {
	// 创建上下文
	ctx, cancel := context.WithCancel(context.Background())
	hs.cancel = cancel

	// 创建定时器
	hs.logger.Info(fmt.Sprintf("设置心跳间隔为 %d 秒", int(hs.heartbeatInterval.Seconds())))
	hs.ticker = time.NewTicker(hs.heartbeatInterval)

	// 创建线程池
	hs.pool, _ = ants.NewPool(hs.poolSize)

	// 启动心跳goroutine
	go func() {
		for {
			select {
			case <-hs.ticker.C:
				hs.handleHeartbeatAll()
			case <-hs.triggerChan:
				hs.handleHeartbeatAll()
			case <-ctx.Done():
				hs.logger.Info("心跳服务已停止")
				return
			}
		}
	}()

	hs.logger.Info("心跳服务已启动")
}

// Stop 停止心跳服务
func (hs *HeartbeatService) Stop() {
	if hs == nil {
		return
	}

	if hs.ticker != nil {
		hs.ticker.Stop()
	}

	if hs.cancel != nil {
		hs.cancel()
	}

	if hs.pool != nil {
		hs.pool.Release()
	}

	hs.logger.Info("[Heartbeat] 心跳任务停止指令已发送")
}

// TriggerManualHeartbeat 手动触发心跳检测
func (hs *HeartbeatService) TriggerManualHeartbeat() {
	hs.logger.Info("收到手动触发心跳检测请求")
	hs.triggerChan <- struct{}{}
	hs.logger.Info("手动心跳检测完成")
}

// TriggerManualHeartbeatAsync 手动触发心跳检测且不等待检测结果
func (hs *HeartbeatService) TriggerManualHeartbeatAsync() {
	hs.logger.Info("收到手动触发异步心跳检测请求")
	go func() {
		hs.triggerChan <- struct{}{}
		hs.logger.Info("手动心跳检测完成")
	}()
}

// sendHeartbeatAll 发送心跳包到所有中继设备
func (hs *HeartbeatService) handleHeartbeatAll() {
	// 记录心跳开始日志
	hs.logger.Debug("开始发送心跳包")

	// 获取所有中继设备
	relays, err := hs.deviceRepo.ListAll()
	if err != nil {
		hs.logger.Error("获取设备列表失败: " + err.Error())
		return
	}

	// 创建线程安全的临时map用于保存所有设备状态
	tempStatusMap := &TempStatusMap{
		data: make(map[string]*DeviceStatus),
		mu:   sync.RWMutex{},
	}

	// 遍历所有连接的设备并发送心跳包
	wg := sync.WaitGroup{}
	for _, relay := range relays {
		// 心跳包之发送给中继设备
		if relay.Type != model.DeviceTypeRelay {
			continue
		}

		id := fmt.Sprintf("%v", relay.ID)
		name := relay.Name

		wg.Add(1)
		err := hs.pool.Submit(func() {
			defer wg.Done()

			err := hs.handleHeartbeatWithStatus(id, tempStatusMap)
			if err != nil {
				hs.logger.Error("[Heartbeat] 向设备 " + name + "(id:" + id + ") 发送心跳包失败: " + err.Error())
			}
		})
		if err != nil {
			hs.logger.Error("向设备 " + name + "(id:" + id + ") 发送心跳包失败(线程池异常): " + err.Error())
		}
	}
	wg.Wait()

	// 获取所有设备列表
	allDevices, err := hs.deviceRepo.ListAll()
	if err != nil {
		hs.logger.Error("获取所有设备列表失败: " + err.Error())
		return
	}

	// 补齐临时map中缺失的设备，缺失的设备全部设为离线状态
	tempStatusMap.mu.Lock()
	for _, device := range allDevices {
		id := fmt.Sprintf("%v", device.ID)
		if _, exists := tempStatusMap.data[id]; !exists {
			tempStatusMap.data[id] = &DeviceStatus{
				Active: false,
			}
		}
	}
	tempStatusMap.mu.Unlock()

	// 将临时状态更新到全局状态池
	hs.deviceStatusPool.SetAllStatuses(tempStatusMap.data)

	hs.logger.Debug("心跳包发送完成")
}

// TempStatusMap 线程安全的临时状态映射
type TempStatusMap struct {
	data map[string]*DeviceStatus
	mu   sync.RWMutex
}

// SetStatus 设置设备状态
func (tsm *TempStatusMap) SetStatus(deviceID string, status *DeviceStatus) {
	tsm.mu.Lock()
	defer tsm.mu.Unlock()
	tsm.data[deviceID] = status
}

// GetStatus 获取设备状态
func (tsm *TempStatusMap) GetStatus(deviceID string) (*DeviceStatus, bool) {
	tsm.mu.RLock()
	defer tsm.mu.RUnlock()
	status, exists := tsm.data[deviceID]
	return status, exists
}

// sendHeartbeat 发送心跳包到所有中继设备
func (hs *HeartbeatService) handleHeartbeatWithStatus(deviceID string, tempStatusMap *TempStatusMap) error {
	// 构造带时间戳的心跳包数据
	heartbeatData := map[string]interface{}{
		"timestamp": time.Now().Unix(),
	}

	// 发送心跳包到设备
	response, err := hs.websocketManager.SendCommandAndWait(deviceID, "heartbeat", heartbeatData, 0)
	if err != nil {
		hs.logger.Error(fmt.Sprintf("向设备 %s 发送心跳包失败: %v", deviceID, err))
		// 更新设备状态为离线
		tempStatusMap.SetStatus(deviceID, &DeviceStatus{
			Active: false,
		})
		return err
	}

	// 记录收到心跳响应
	hs.logger.Debug(fmt.Sprintf("收到来自设备 %s 的心跳响应: %+v", deviceID, response))

	// 有响应中继设备就是在线
	tempStatusMap.SetStatus(deviceID, &DeviceStatus{
		Active: true,
	})

	// 时间戳校验
	if response.Timestamp.Unix() != heartbeatData["timestamp"] {
		hs.logger.Error(fmt.Sprintf("心跳响应时间戳校验失败: %v , 响应时间戳应当与发送的时间戳一致", response))
		return errors.New("心跳响应时间戳校验失败")
	}

	// 解析响应中的下级设备状态
	type DeviceStatusInfo struct {
		DeviceID   string `json:"device_id"`
		DeviceType string `json:"device_type"`
		Status     string `json:"status"`
	}

	type HeartbeatResponseData struct {
		Devices []DeviceStatusInfo `json:"devices"`
	}

	var responseData HeartbeatResponseData
	if err := response.ParseData(&responseData); err != nil {
		hs.logger.Error(fmt.Sprintf("解析设备 %s 的心跳响应数据失败: %v", deviceID, err))
		return err
	}

	// 更新所有下级设备的状态
	for _, device := range responseData.Devices {
		// 根据设备状态确定Active值
		isActive := device.Status == "running" || device.Status == "online" || device.Status == "active"

		tempStatusMap.SetStatus(device.DeviceID, &DeviceStatus{
			Active: isActive,
		})
	}

	return nil
}