package main

import (
	"archive/zip"
	"errors"
	"fmt"
	"io"
	"os"
	"path/filepath"
)
func main() {
	// Specify the path of the directory where zip file is placed
	basePath := "/home/madhurbhaiya/Downloads"
	inputZipFilePath := filepath.Join(basePath, "checksum-error.zip")

	// Open the zip reader
	zipFile, err := zip.OpenReader(inputZipFilePath)
	if err != nil {
		fmt.Println(err)
		return
	}
	if len(zipFile.File) == 0 {
		fmt.Println("No files in the input zip")
		return
	}

	for _, zipFl := range zipFile.File {
		destFilePath := filepath.Join(basePath,"extracted-" + zipFl.Name)
		if err = ExtractFileFromZip(zipFl, destFilePath); err != nil {
			fmt.Println(err)
		}
	}
}

// ExtractFileFromZip extracts a file from given zip srcfile and stores the content at destFilePath
func ExtractFileFromZip(srcfile *zip.File, destFilePath string) error {
	// Open the Zip file
	src, err := srcfile.Open()
	if err != nil {
		return err
	}
	defer func(src io.ReadCloser) {
		err = src.Close()
		if err != nil {
			fmt.Println(err)
		}
	}(src)

	// Create the destintation file
	_ = os.MkdirAll(filepath.Dir(destFilePath), os.ModePerm)
	out, err := os.Create(destFilePath)
	if err != nil {
		return err
	}
	defer func(out *os.File) {
		err = out.Close()
		if err != nil {
			fmt.Println(err)
		}
	}(out)

	// Copy in chunks for G110: Potential DoS vulnerability via decompression bomb (gosec)
	err = nil // Reinitialize err
	for {
		_, err = io.CopyN(out, src, 1024_00) // 100 * 1024 = 100 kB
		if err != nil {
			break
		}
	}
	// Reached EOF - All ok, else it is some other error, Need to return it.
	if errors.Is(err, io.EOF) {
		return nil
	}
	return err
}