rts-sim-testing-service/third_party/message/can_btm_rsp.go

package message

import "log/slog"

// CreateBtmRspFramesData 数据帧与状态应答帧同时发送给ATP
// 共17帧，17X12个字节，每个帧12字节
// msg - 应答器报文
// msgPackError - true BTM解包发生错误，则数据帧及CRC32A/B全填“0xFF”
func CreateBtmRspFramesData(statusRsp *BtmStatusRspFrame, msg []byte, msgPackError bool, msgTimeA uint32, msgTimeB uint32, tkTimeB uint32) ([]byte, bool) {
	if len(msg) > 104 { //数据帧最多存储13*8个字节
		return nil, false
	}
	//最近一次ATP查询请求序列号
	sn := statusRsp.FId.ID4
	//13个BtmDataMessageFrame [0x00,0x0c]
	dms := make([]*BtmDataMessageFrame, 13)
	for mr := 0x00; mr <= 0x0c; mr++ {
		dms[mr] = NewBtmDataMessageFrame(sn, byte(mr))
		dms[mr].Message = make([]byte, 8) //8字节数组，默认值0
		//
		if !msgPackError {
			mi := mr * 8
			if mi < len(msg) { //数据帧中有<=8个字节数据
				if mi+7 < len(msg) {
					dms[mr].Message = msg[mi : mi+8]
				} else {
					for i, d := range msg[mi:] {
						dms[mr].Message[i] = d
					}
				}
			}
		} else { //BTM解包发生错误，则数据帧及CRC32A/B全填“0xFF”
			for c := 0; c < 8; c++ {
				dms[mr].Message[c] = 0xff
			}
		}
	}
	//
	dtA := NewBtmDataMessageTimeAFrame(sn)
	dtA.TimeA = msgTimeA
	if !msgPackError {
		var crc32AData []byte
		crc32AData = append(crc32AData, msg...)
		crc32AData = append(crc32AData, canTimeToBytes(dtA.TimeA)...)
		dtA.Crc32A = calculateDataRspCrc32A(crc32AData) //CRC32A的校验范围是：报文+时间戳A
	} else { //BTM解包发生错误，则数据帧及CRC32A/B全填“0xFF”
		dtA.Crc32A = 0xff_ff_ff_ff
	}
	//
	dtB := NewBtmDataMessageTimeBFrame(sn)
	dtB.TimeB = msgTimeB
	if !msgPackError {
		var crc32BData []byte
		crc32BData = append(crc32BData, msg...)
		crc32BData = append(crc32BData, canTimeToBytes(dtB.TimeB)...)
		dtB.Crc32B = calculateDataRspCrc32B(crc32BData) //CRC32B的校验范围是：报文+时间戳B
	} else { //BTM解包发生错误，则数据帧及CRC32A/B全填“0xFF”
		dtB.Crc32B = 0xff_ff_ff_ff
	}
	//
	end := NewBtmDataMessageEndFrame(sn)
	end.TkB = tkTimeB
	//
	crc32CData := make([]byte, 0, 132) //17*8-4
	rt := make([]byte, 0, 204)         //17*12
	// 状态应答帧
	statusData := statusRsp.Encode()
	crc32CData = append(crc32CData, canFrameContent(statusData)...)
	rt = append(rt, statusData.GetData()...)
	// 数据帧
	for _, dm := range dms {
		dmData := dm.Encode()
		crc32CData = append(crc32CData, canFrameContent(dmData)...)
		rt = append(rt, dmData.GetData()...)
	}
	// 消息时刻A
	dtAData := dtA.Encode()
	crc32CData = append(crc32CData, canFrameContent(dtAData)...)
	rt = append(rt, dtAData.GetData()...)
	// 消息时刻B
	dtBData := dtB.Encode()
	crc32CData = append(crc32CData, canFrameContent(dtBData)...)
	rt = append(rt, dtBData.GetData()...)
	// 消息结束帧
	crc32CData = append(crc32CData, canTimeToBytes(end.TkB)...)
	if len(crc32CData) != 132 {
		slog.Warn("BtmDataMessageEndFrame crc32 校验数据须132字节")
		return nil, false
	}
	end.Crc32C = calculateDataRspCrc32C(crc32CData)
	rt = append(rt, end.Encode().GetData()...)
	if len(rt) != 204 {
		slog.Warn("BTM响应ATP 17帧须136字节")
		return nil, false
	}
	//
	return rt, true
}

// CAN帧中除去开始29bits的剩余8字节数据
func canFrameContent(canFrame CanBusData) []byte {
	rd := NewCanBitsReader(canFrame.GetData(), canFrame.GetLastRowBitsLen())
	rd.ReadByte()  //ID1
	rd.ReadByte()  //ID2
	rd.ReadByte()  //ID3
	rd.ReadBits(5) //ID4
	//
	rt := make([]byte, 0, 8)
	for {
		d, ok := rd.ReadByte()
		if !ok {
			break
		}
		rt = append(rt, d)
	}
	if len(rt) != 8 {
		panic("CAN帧中数据体须为8字节")
	}
	return rt
}