// Copyright 2024 Matthew Rich <matthewrich.conf@gmail.com>. All rights reserved.

package containerlog

import (
	"fmt"
	"errors"
	"encoding/binary"
)

type StreamType byte

const (
	StreamStdin StreamType = 0x0
	StreamStdout StreamType = 0x1
	StreamStderr StreamType = 0x2
)

var (
	ErrInvalidStreamType error = errors.New("Invalid container log stream type")
)

func (s StreamType) Validate() error {
	switch s {
	case StreamStdin, StreamStdout, StreamStderr:
		return nil
	}
	return fmt.Errorf("%w: %d", ErrInvalidStreamType, s)
}

func (s StreamType) Log(msg string) (log []byte) {
	msgLen := len(msg)
	log = make([]byte, 8 + msgLen)
	binary.BigEndian.PutUint64(log, uint64(msgLen))
	log[0] = byte(s)
	copy(log[8:], []byte(msg))
	return
}