package multifile

import (
	"io"
	"os"
	"time"

	"gitlab.com/tozd/go/errors"
)

type MultiFile struct {
	files []FileLike
	io.Writer
}

type FileLike interface {
	io.WriteCloser
	Name() string
}

func NewMultiFile(files ...FileLike) *MultiFile {
	writers := make([]io.Writer, len(files))
	for i, w := range files {
		writers[i] = w
	}

	return &MultiFile{
		files:  files,
		Writer: io.MultiWriter(writers...),
	}
}

func (mf *MultiFile) Close() error {
	var lastErr error
	for _, w := range mf.files {
		err := w.Close()
		if err != nil {
			lastErr = err
		}
	}

	return lastErr
}

func (mf *MultiFile) Name() string {
	return mf.files[0].Name()
}

func (mf *MultiFile) Chtimes(mtime time.Time) error {
	var lastErr error
	for _, f := range mf.files {
		err := os.Chtimes(f.Name(), mtime, mtime)
		if err != nil {
			lastErr = errors.Join(lastErr, err)
		}
	}

	return lastErr
}