package beijing11

import (
	"encoding/binary"
	"fmt"
	"hash/crc32"
	"joylink.club/bj-rtsts-server/sys_error"
)

type BaseStruct struct {
	ID          byte
	ControlWord byte
	Data        []byte
}

func (m *BaseStruct) Decode(buf []byte) error {
	if buf[0] != FrameHead {
		return sys_error.New(logTag + "帧头不正确：" + fmt.Sprintf("%02X", buf[0]))
	}
	if buf[len(buf)-1] != FrameTail {
		return sys_error.New(logTag + "帧尾不正确：" + fmt.Sprintf("%02X", buf[len(buf)-1]))
	}
	crc := crc32.ChecksumIEEE(buf[1 : len(buf)-5])
	if crc != binary.BigEndian.Uint32(buf[len(buf)-5:len(buf)-1]) {
		return sys_error.New(logTag + "CRC校验失败")
	}
	m.ID = buf[1]
	m.ControlWord = buf[2]
	m.Data = buf[5 : len(buf)-5]
	return nil
}

func (m *BaseStruct) Encode() []byte {
	var data []byte
	data = append(data, FrameHead)
	data = append(data, m.ID)
	data = append(data, m.ControlWord)
	data = binary.BigEndian.AppendUint16(data, uint16(len(m.Data)))
	data = append(data, m.Data...)
	crc := crc32.ChecksumIEEE(data[1:])
	data = binary.BigEndian.AppendUint32(data, crc)
	data = append(data, FrameTail)
	return data
}

type ReadRegisterReq struct {
	RegisterAddr []uint16 //寄存器地址
}

func (r *ReadRegisterReq) Decode(buf []byte) error {
	if len(buf)%2 != 0 {
		return sys_error.New(logTag + "读寄存器数据字节长度不是2的倍数")
	}
	for i := 0; i < len(buf); i += 2 {
		r.RegisterAddr = append(r.RegisterAddr, binary.BigEndian.Uint16(buf[i:i+2]))
	}
	return nil
}

type ReadRegisterRes struct {
	RegisterData [][]byte //寄存器数据
}

func (r *ReadRegisterRes) Encode() []byte {
	var data []byte
	for _, datum := range r.RegisterData {
		data = append(data, datum...)
	}
	return data
}

type WriteRegisterReq struct {
	RegisterAddr []uint16 //寄存器地址
	RegisterData [][]byte //寄存器数据
}

func (w *WriteRegisterReq) Decode(buf []byte) error {
	if len(buf)%6 != 0 {
		return sys_error.New(logTag + "写寄存器数据字节长度不是6的倍数")
	}
	for i := 0; i < len(buf); i += 6 {
		w.RegisterAddr = append(w.RegisterAddr, binary.BigEndian.Uint16(buf[i:i+2]))
		w.RegisterData = append(w.RegisterData, buf[i+2:i+6])
	}
	return nil
}