package zip

import (
	"archive/zip"
	"io"
	"os"

	"git.sa-roci.de/oss/go_zipper"
)

// NewUnzipper makes a new Unzipper.
func NewUnzipper(zipFilename string) zipper.Unzipper {
	uz := zUnzipper{
		Unzipper: zipper.NewBaseUnzipper(zipFilename),
	}
	uz.SetDecompressor(uz)
	return uz
}

type zUnzipper struct {
	zipper.Unzipper
}

func (uz zUnzipper) OpenReader(zipFile *os.File) (err error) {
	var reader *zip.ReadCloser
	if reader, err = zip.OpenReader(zipFile.Name()); err == nil {
		uz.SetReader(reader)
	}
	return
}

func (uz zUnzipper) Decompress(targetFolderPathInFileSystem string) (err error) {
	if zipReader, ok := uz.GetReader().(*zip.ReadCloser); ok {
		if err = zipper.MakeSurePathExists(targetFolderPathInFileSystem+"/dummy.file", 0644); err == nil {
			for _, entry := range zipReader.File {
				outputPath := zipper.PrependPath(entry.Name, targetFolderPathInFileSystem)
				if !entry.FileInfo().IsDir() {
					if err = zipper.MakeSurePathExists(outputPath, 0644); err == nil {
						var dstFile *os.File
						if dstFile, err = os.OpenFile(outputPath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, entry.Mode()); err == nil {
							defer dstFile.Close()
							var archivedFileData io.ReadCloser
							if archivedFileData, err = entry.Open(); err == nil {
								defer archivedFileData.Close()
								_, err = io.Copy(dstFile, archivedFileData)
							}
						}
					}
				} else {
					err = zipper.MakeSurePathExists(outputPath+"/dummy.file", 0644)
				}

				if err != nil {
					break
				}
			}
		}
	}
	return
}