package extract

import (
	"archive/tar"
	"compress/bzip2"
	"compress/gzip"
	"errors"
	"io"
	"os"
)

func extractTar(archivePath string, archiveFormat format, writer *entryWriter) error {
	file, err := os.Open(archivePath)
	if err != nil {
		return err
	}
	defer file.Close()

	if archiveFormat == formatTar {
		if info, err := file.Stat(); err == nil {
			writer.progress.SetTotal(info.Size())
		}
	}

	source, err := decompress(file, archiveFormat)
	if err != nil {
		return err
	}

	reader := tar.NewReader(source)
	for {
		header, err := reader.Next()
		if errors.Is(err, io.EOF) {
			return nil
		}
		if err != nil {
			return err
		}

		switch header.Typeflag {
		case tar.TypeDir:
			err = writer.writeDirectory(header.Name)
		case tar.TypeReg:
			err = writer.writeFile(header.Name, reader)
		}
		if err != nil {
			return err
		}
	}
}

func decompress(file *os.File, archiveFormat format) (io.Reader, error) {
	switch archiveFormat {
	case formatTarGzip:
		return gzip.NewReader(file)
	case formatTarBzip2:
		return bzip2.NewReader(file), nil
	default:
		return file, nil
	}
}