package main

import (
	"cicv-data-closedloop/pjisuv_msgs"
	"fmt"
	"math"
)

type Object struct {
	ID            uint32
	StableAge     int
	LastExistTime float64
}

var objectsStability = make(map[uint32]Object)

func Topic() string {
	return "/tpperception"
}

// Label todo 禁止存在下划线_
func Label() string {
	return "LowSpdTruckAhead"
}

// speedCheck 目标物速度检测
func speedCheck(obj *pjisuv_msgs.PerceptionObject) bool {
	const targetMinSpeed = 2 / 3.6  // m/s
	const targetMaxSpeed = 20 / 3.6 // m/s

	return targetMinSpeed < obj.Speed && obj.Speed < targetMaxSpeed
}

// typeCheck 目标物类型检测
// × 金龙车：CAR_TYPE=0, TRUCK_TYPE=1, PEDESTRIAN_TYPE=2, CYCLIST_TYPE=3, UNKNOWN_TYPE=4, UNKNOWN_MOVABLE_TYPE=5, UNKNOWN_UNMOVABLE_TYPE=6
// √ 多功能车：UNKNOWN TYPE=O, PEDESTRIAN TYPE=1, CAR TYPE=2, TRUCK TYPE=3, Bicycle TYPE=4, Tricycle TYPE=5, Traffic Cone TYPE=6
func typeCheck(obj *pjisuv_msgs.PerceptionObject) bool {
	const targetType uint8 = 3

	return targetType == obj.Type
}

// posCheck 判断目标物位置关系
func posCheck(obj *pjisuv_msgs.PerceptionObject) bool {
	const laneWidth = 3.5 // m

	return obj.X > 0 && math.Abs(float64(obj.Y)) < laneWidth*1.5
}

// Rule 检测前方大车低速行驶
func Rule(msg *pjisuv_msgs.PerceptionObjects) string {
	defer func() {
		if r := recover(); r != nil {
			fmt.Println(fmt.Sprintf("Recovered from panic: [%s], [%#v]", Label(), r))
		}
	}()

	const MinStableFrameCount = 5
	const MaxTimeBetweenFrame = 0.5

	for _, obj := range msg.Objs {

		// 判断目标物是否满足筛选条件
		if speedCheck(&obj) && posCheck(&obj) && typeCheck(&obj) {

			// 目标物初见存档
			if prevObjRecord, exists := objectsStability[obj.Id]; exists == false {
				objectsStability[obj.Id] = Object{
					ID:            obj.Id,
					StableAge:     1,
					LastExistTime: msg.Header.TimeStamp,
				}
			} else {
				currObjRecord := Object{
					ID:            obj.Id,
					StableAge:     1,
					LastExistTime: msg.Header.TimeStamp,
				}

				// 目标物确认/更新/重置
				if currObjRecord.LastExistTime-prevObjRecord.LastExistTime <= MaxTimeBetweenFrame { // 目标物消失不超过0.5s
					currObjRecord.StableAge = prevObjRecord.StableAge + 1
					if currObjRecord.StableAge == MinStableFrameCount {
						delete(objectsStability, obj.Id)
						return Label()
					}
				}
				objectsStability[obj.Id] = currObjRecord
			}
		}
	}
	return ""
}