package fsUtils

import (
	"archive/zip"
	"fmt"
	"io"
	"os"
	"path/filepath"
	"strings"

	"github.com/rs/zerolog/log"
)

func AddFileToZip(zipWriter *zip.Writer, filename string) error {

	fileToZip, err := os.Open(filename)
	if err != nil {
		return fmt.Errorf("failed to open file %s, %w", filename, err)
	}
	defer fileToZip.Close()

	// Get the file information
	info, err := fileToZip.Stat()
	if err != nil {
		return fmt.Errorf("failed to get file information %s, %w", filename, err)
	}

	header, err := zip.FileInfoHeader(info)
	if err != nil {
		return err
	}

	// Using FileInfoHeader() above only uses the basename of the file. If we want
	// to preserve the folder structure we can overwrite this with the full path.
	header.Name = filepath.Base(filename)

	// Change to deflate to gain better compression
	// see http://golang.org/pkg/archive/zip/#pkg-constants
	header.Method = zip.Deflate

	writer, err := zipWriter.CreateHeader(header)
	if err != nil {
		return fmt.Errorf("failed to create header in zip for %s, %w", filename, err)
	}
	_, err = io.Copy(writer, fileToZip)
	return err
}

func AddStrToZip(writer *zip.Writer, logs string, fileName string) error {
	if zipFile, err := writer.Create(fileName); err != nil {
		return fmt.Errorf("couldn't create a log file inside zip for %s, %w", fileName, err)
	} else {
		if _, err = zipFile.Write([]byte(logs)); err != nil {
			return fmt.Errorf("couldn't write logs to zip file: %s, %w", fileName, err)
		}
	}
	return nil
}

func Unzip(reader *zip.Reader, dest string) error {
	dest, _ = filepath.Abs(dest)
	_ = os.MkdirAll(dest, os.ModePerm)

	// Closure to address file descriptors issue with all the deferred .Close() methods
	extractAndWriteFile := func(f *zip.File) error {
		rc, err := f.Open()
		if err != nil {
			return err
		}
		defer func() {
			if err := rc.Close(); err != nil {
				panic(err)
			}
		}()

		path := filepath.Join(dest, f.Name)

		// Check for ZipSlip (Directory traversal)
		if !strings.HasPrefix(path, filepath.Clean(dest)+string(os.PathSeparator)) {
			return fmt.Errorf("illegal file path: %s", path)
		}

		if f.FileInfo().IsDir() {
			_ = os.MkdirAll(path, f.Mode())
		} else {
			_ = os.MkdirAll(filepath.Dir(path), f.Mode())
			log.Info().Str("path", path).Msg("Writing HAR file...")
			f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, f.Mode())
			if err != nil {
				return err
			}
			defer func() {
				if err := f.Close(); err != nil {
					panic(err)
				}
				log.Info().Str("path", path).Msg("HAR file at:")
			}()

			_, err = io.Copy(f, rc)
			if err != nil {
				return err
			}
		}
		return nil
	}

	for _, f := range reader.File {
		err := extractAndWriteFile(f)
		if err != nil {
			return err
		}
	}

	return nil
}