package nvcs

import (
	"container/list"
	"fmt"
	"time"

	"gat1400Exchange/config"
	"gat1400Exchange/models"
	"gat1400Exchange/pkg/logger"
)

type simpleCache struct {
	data       *list.List
	expiration time.Duration
}

func newCache(expiration time.Duration) *simpleCache {
	return &simpleCache{
		data:       list.New(),
		expiration: expiration,
	}
}

// 存储数据到缓存中
func (c *simpleCache) store(data ElevatorRunData) {
	var floorChanged = true

	// 取RFID楼层
	if config.RFIDConf.ReadFloor && gRFIDFloor != data.Floor {
		if data.RunState == RunStop {
			logger.Warn("A floor error has occurred rfid epc %s, nvcs floor %s", gRFIDFloor, data.Floor)
		}

		data.Floor = gRFIDFloor
	}

	if data.Floor == "" {
		return
	}

	lastData := c.data.Back()

	// 如果楼层相同，并且数据在1秒内，则忽略
	if lastData != nil {
		if lastData.Value.(ElevatorRunData).Floor == data.Floor {
			floorChanged = false
			if lastData.Value.(ElevatorRunData).Timestamp == data.Timestamp {
				return
			}
		}
	}

	c.data.PushBack(data)

	if !floorChanged {
		return
	}

	// 数据库保存一份
	var d = models.Positions{
		DeviceId:   data.Device,
		Pos:        data.Floor,
		RunDir:     data.RunState,
		CreateTime: time.Now().Unix(),
		TimeString: time.Now().Format("2006-01-02 15:04:05"),
	}

	err := d.Save()
	if err != nil {
		logger.Warn("Device position update error:%s", err.Error())
	}

	// 写OSD
	var runStateStr string
	if config.NVCSConf.RunState {
		if data.RunState == RunUp {
			runStateStr = "上"
		} else if data.RunState == RunDown {
			runStateStr = "下"
		}
	}

	// 设置osd  格式 "1F上 固 枪"
	if config.NVCSConf.OSD != "" {
		floorText := fmt.Sprintf("%s%s %s", data.Floor, runStateStr, config.NVCSConf.OSD)

		// 调用hik api 将文字添加到osd的左下角
		err = addFloorToOSD(floorText)
		if err != nil {
			logger.Warn("%s", err.Error())
		}
	}
}

// 删除过期数据
func (c *simpleCache) cleanExpired() {
	now := time.Now()

	// 从队列头部开始检查是否有过期数据
	for c.data.Len() > 0 {
		elem := c.data.Front() // 获取队列头部的元素
		item := elem.Value.(ElevatorRunData)
		if now.Sub(time.Unix(item.Timestamp, 0)) > c.expiration {
			// 如果数据已经过期，则从队列中删除
			c.data.Remove(elem)
		} else {
			// 因为数据按时间顺序存储，遇到不过期的数据后就可以停止检查
			break
		}
	}
}

func (c *simpleCache) getPositionByTime(timestamp int64) (runData ElevatorRunData) {
	node := c.data.Back() // 从链表尾部开始
	for node != nil {
		if data, ok := node.Value.(ElevatorRunData); ok {
			if data.Timestamp >= timestamp {
				runData = data
				node = node.Prev() // 向前移动节点
			} else {
				break
			}
		} else {
			break
		}
	}

	return
}

func (c *simpleCache) getMovePosition(timestamp int64, floor string) (runData ElevatorRunData) {
	logger.Debug("getMovePosition")
	node := c.data.Back() // 从链表末尾开始

	// 找到最近的符合时间戳的节点
	for node != nil {
		if data, ok := node.Value.(ElevatorRunData); ok {
			if data.Timestamp >= timestamp {
				node = node.Prev() // 向前移动节点
			} else {
				break
			}
		} else {
			break
		}
	}

	// 如果找到的节点的时间戳符合要求，继续检查楼层
	if node != nil {
		if current, ok := node.Value.(ElevatorRunData); ok && current.Timestamp >= timestamp {
			for node != nil {
				if nextNode := node.Next(); nextNode != nil {
					logger.Debug("next node %v", nextNode.Value.(ElevatorRunData))
					if nextData, ok := nextNode.Value.(ElevatorRunData); ok {
						if nextData.Floor == floor {
							node = nextNode // 向前移动节点
						} else {
							break
						}
					}
				} else {
					break
				}
			}

			// 如果找到的楼层与目标楼层不同，返回该数据
			if current.Floor != floor {
				runData = current
			}
		}
	}

	return
}