package main

import (
	"encoding/binary"
	"io"
)

const (
	RemoteGetState            = uint32(0x01)
	RemoteHandleMutation      = uint32(0x02)
	ResponseBody              = uint32(0x03)
	RemoteGetStateReply       = uint32(0x04)
	RemoteHandleMutationReply = uint32(0x05)
)

type CartPacket struct {
	Version     uint32
	MessageType uint32
	DataLength  uint64
	Id          CartId
}

type Packet struct {
	Version     uint32
	MessageType uint32
	DataLength  uint64
}

func ReadPacket(conn io.Reader, packet *Packet) error {
	return binary.Read(conn, binary.LittleEndian, packet)
}

func ReadCartPacket(conn io.Reader, packet *CartPacket) error {
	return binary.Read(conn, binary.LittleEndian, packet)
}

func GetPacketData(conn io.Reader, len uint64) ([]byte, error) {
	if len == 0 {
		return []byte{}, nil
	}
	data := make([]byte, len)
	_, err := conn.Read(data)
	return data, err
}

// func ReceivePacket(conn io.Reader) (uint32, []byte, error) {
// 	var packet Packet
// 	err := ReadPacket(conn, &packet)
// 	if err != nil {
// 		return 0, nil, err
// 	}

// 	data, err := GetPacketData(conn, packet.DataLength)
// 	if err != nil {
// 		return 0, nil, err
// 	}
// 	return packet.MessageType, data, nil
// }