package utils

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

func Zip(zipPath string, paths ...string) error {
	// Create zip file and it's parent dir.
	if err := os.MkdirAll(filepath.Dir(zipPath), os.ModePerm); err != nil {
		return err
	}
	archive, err := os.Create(zipPath)
	if err != nil {
		return err
	}
	defer archive.Close()

	// New zip writer.
	zipWriter := zip.NewWriter(archive)
	defer zipWriter.Close()

	// Traverse the file or directory.
	for _, rootPath := range paths {
		// Remove the trailing path separator if path is a directory.
		rootPath = strings.TrimSuffix(rootPath, string(os.PathSeparator))

		// Visit all the files or directories in the tree.
		err = filepath.Walk(rootPath, walkFunc(rootPath, zipWriter))
		if err != nil {
			return err
		}
	}
	return nil
}

func walkFunc(rootPath string, zipWriter *zip.Writer) filepath.WalkFunc {
	return func(path string, info fs.FileInfo, err error) error {
		if err != nil {
			return err
		}

		// If a file is a symbolic link it will be skipped.
		if info.Mode()&os.ModeSymlink != 0 {
			return nil
		}

		// Create a local file header.
		header, err := zip.FileInfoHeader(info)
		if err != nil {
			return err
		}

		// Set compression method.
		header.Method = zip.Deflate

		// Set relative path of a file as the header name.
		header.Name, err = filepath.Rel(rootPath, path)
		if err != nil {
			return err
		}
		if info.IsDir() {
			header.Name += string(os.PathSeparator)
		}

		// Create writer for the file header and save content of the file.
		headerWriter, err := zipWriter.CreateHeader(header)
		if err != nil {
			return err
		}
		if info.IsDir() {
			return nil
		}
		fmt.Println(header.Name)
		f, err := os.Open(path)
		if err != nil {
			return err
		}
		defer f.Close()
		_, err = io.Copy(headerWriter, f)
		return err
	}
}

func Unzip(zipPath, dstDir string, cb func(per1000 int)) error {
	// open zip file
	reader, err := zip.OpenReader(zipPath)
	if err != nil {
		return err
	}
	defer reader.Close()

	total := len(reader.File)
	for index, file := range reader.File {
		per1000 := int(float32(index+1) / float32(total) * 1000)
		// log.Println("unzip=>", file.Name, index, "/", len(reader.File))
		log.Println("unzip=>", file.Name)
		if cb != nil {
			cb(per1000)
		}
		if err := unzipFile(file, dstDir); err != nil {
			return err
		}
	}
	return nil
}

func unzipFile(file *zip.File, dstDir string) error {
	// create the directory of file
	filePath := path.Join(dstDir, file.Name)
	if file.FileInfo().IsDir() {
		if err := os.MkdirAll(filePath, os.ModePerm); err != nil {
			return err
		}
		return nil
	}
	if err := os.MkdirAll(filepath.Dir(filePath), os.ModePerm); err != nil {
		return err
	}

	// open the file
	rc, err := file.Open()
	if err != nil {
		return err
	}
	defer rc.Close()

	// create the file
	w, err := os.Create(filePath)
	if err != nil {
		return err
	}
	defer w.Close()

	// save the decompressed file content
	_, err = io.Copy(w, rc)
	return err
}