package fileutil

import (
	"archive/zip"
	"bytes"
	"fmt"
	"os"
	"path/filepath"
)

// IsFileExists checks if the file exists in the provided path
func IsFileExists(filename string) bool {
	info, err := os.Stat(filename)
	if os.IsNotExist(err) {
		return false
	}
	if err != nil {
		return false
	}
	return !info.IsDir()
}

// CompressDir compresses the directory into a zip file
func CompressDir(dir string) error {
	files, err := os.ReadDir(dir)
	if err != nil {
		return fmt.Errorf("read dir error: %w", err)
	}
	if len(files) == 0 {
		// Return an error if no files are found in the directory
		return fmt.Errorf("no files to compress in: %s", dir)
	}

	buffer := new(bytes.Buffer)
	zipWriter := zip.NewWriter(buffer)
	defer func() {
		_ = zipWriter.Close()
	}()

	for _, file := range files {
		if err := addFileToZip(zipWriter, filepath.Join(dir, file.Name())); err != nil {
			return fmt.Errorf("failed to add file to zip: %w", err)
		}
	}

	if err := zipWriter.Close(); err != nil {
		return fmt.Errorf("error closing zip writer: %w", err)
	}

	zipFilename := filepath.Join(dir, filepath.Base(dir)+".zip")
	return writeFile(buffer, zipFilename)
}

func addFileToZip(zw *zip.Writer, filename string) error {
	content, err := os.ReadFile(filename)
	if err != nil {
		return fmt.Errorf("error reading file %s: %w", filename, err)
	}

	fw, err := zw.Create(filepath.Base(filename))
	if err != nil {
		return fmt.Errorf("error creating zip entry for %s: %w", filename, err)
	}

	if _, err = fw.Write(content); err != nil {
		return fmt.Errorf("error writing content to zip for %s: %w", filename, err)
	}

	if err = os.Remove(filename); err != nil {
		return fmt.Errorf("error removing original file %s: %w", filename, err)
	}

	return nil
}

func writeFile(buffer *bytes.Buffer, filename string) error {
	outFile, err := os.Create(filename)
	if err != nil {
		return fmt.Errorf("error creating output file %s: %w", filename, err)
	}
	defer func() {
		_ = outFile.Close()
	}()

	if _, err = buffer.WriteTo(outFile); err != nil {
		return fmt.Errorf("error writing data to file %s: %w", filename, err)
	}

	return nil
}