package rpc

import (
	"encoding/binary"
	"io"
	"net"
)

func TCPWriteData(conn net.Conn, buf []byte) error {
	var wErr error

	prefix := make([]byte, 4)
	binary.BigEndian.PutUint32(prefix, uint32(len(buf)))

	_, wErr = conn.Write(prefix)
	if nil != wErr {
		return wErr
	}
	_, wErr = conn.Write(buf)
	if nil != wErr {
		return wErr
	}

	return nil
}

func TCPReadData(conn net.Conn) ([]byte, error) {
	var (
		buf  []byte
		rErr error
	)

	prefix := make([]byte, 4)
	_, rErr = io.ReadFull(conn, prefix)
	if nil != rErr {
		return nil, rErr
	}

	length := binary.BigEndian.Uint32(prefix)

	buf = make([]byte, int(length))
	_, rErr = io.ReadFull(conn, buf)
	if nil != rErr {
		return nil, rErr
	}

	return buf, nil
}