package compression

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

// 参考 https://www.cnblogs.com/super-codex/articles/17124567.html
type ZipHandler struct {
}

func NewZipHandler() *ZipHandler {
	return &ZipHandler{}
}

// UnZip
// 解压zip文件到指定目录，包含顶层文件夹
func (z *ZipHandler) UnZip(src, dst string) error {
	archive, err := zip.OpenReader(src)
	if err != nil {
		return err
	}
	defer func(archive *zip.ReadCloser) {
		err := archive.Close()
		if err != nil {
			return
		}
	}(archive)

	for _, item := range archive.File {
		filePath := filepath.Join(dst, item.Name)

		if err := os.MkdirAll(filepath.Dir(filePath), os.ModePerm); err != nil {
			return err
		}

		if item.FileInfo().IsDir() {
			err := os.MkdirAll(filePath, os.ModePerm)
			if err != nil {
				return err
			}
			continue
		}

		file, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, item.Mode())
		if err != nil {
			return err
		}

		fileInArchive, err := item.Open()
		if err != nil {
			return err
		}

		if _, err := io.Copy(file, fileInArchive); err != nil {
			return err
		}
	}
	return nil
}

// UnZipTo
// 解压zip文件到指定目录，不包含顶层文件夹，只是将文件解压到指定目录
func (z *ZipHandler) UnZipTo(src, dst string) error {
	archive, err := zip.OpenReader(src)
	if err != nil {
		return err
	}
	defer func(archive *zip.ReadCloser) {
		err := archive.Close()
		if err != nil {
			return
		}
	}(archive)

	for _, item := range archive.File {
		splitPath := strings.Split(item.Name, string(os.PathSeparator))
		targetPath := strings.Join(splitPath[1:], string(os.PathSeparator))
		filePath := filepath.Join(dst, targetPath)

		if err := os.MkdirAll(filepath.Dir(filePath), os.ModePerm); err != nil {
			return err
		}

		if item.FileInfo().IsDir() {
			err := os.MkdirAll(filePath, os.ModePerm)
			if err != nil {
				return err
			}
			continue
		}

		file, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, item.Mode())
		if err != nil {
			return err
		}
		fileInArchive, err := item.Open()
		if err != nil {
			return err
		}
		if _, err := io.Copy(file, fileInArchive); err != nil {
			return err
		}
	}
	return nil
}