package util

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

	"golang.org/x/crypto/ssh"

	"github.com/pkg/sftp"
)

type SftpStorageOpts struct {
	Host     string
	Port     int
	User     string
	Password string
	// Logger   *slog.Logger
}

type SftpStorage struct {
	SftpStorageOpts
	sshcon  *ssh.Client
	Sftpcon *sftp.Client
}

func NewSsftp(c SftpStorageOpts) SftpStorage {
	return SftpStorage{SftpStorageOpts: c}
}

// caller needs to defer
func (s *SftpStorage) Close() {
	s.Sftpcon.Close()
	s.sshcon.Close()
}

func (s *SftpStorage) Connect() (err error) {
	var auths []ssh.AuthMethod

	if s.Password != "" {
		auths = append(auths, ssh.Password(s.Password))
	}

	// Initialize client configuration
	config := ssh.ClientConfig{
		User: s.User,
		Auth: auths,
		// ignore host key check
		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
	}

	addr := fmt.Sprintf("%s:%d", s.Host, s.Port)

	// Connect to server
	s.sshcon, err = ssh.Dial("tcp", addr, &config)
	if err != nil {
		return fmt.Errorf("failed to connecto to [%s]: %v", addr, err)
	}

	// Create new SFTP client
	s.Sftpcon, err = sftp.NewClient(s.sshcon)
	if err != nil {
		return fmt.Errorf("unable to start SFTP subsystem [%s]: %v", addr, err)
	}
	return
}

func (s *SftpStorage) UploadFile(localFile, remoteFile string) (err error) {

	srcFile, err := os.Open(localFile)
	if err != nil {
		return fmt.Errorf("unable to open localfile file: %v", err)
	}
	defer srcFile.Close()

	parent := filepath.Dir(remoteFile)
	path := string(filepath.Separator)
	dirs := strings.Split(parent, path)
	for _, dir := range dirs {
		path = filepath.Join(path, dir)
		s.Sftpcon.Mkdir(path)
	}

	dstFile, err := s.Sftpcon.OpenFile(remoteFile, (os.O_WRONLY | os.O_CREATE | os.O_TRUNC))
	if err != nil {
		return fmt.Errorf("unable to open remote file: %v", err)
	}
	defer dstFile.Close()

	_, err = io.Copy(dstFile, srcFile)
	if err != nil {
		return fmt.Errorf("unable to upload file: %v", err)
	}

	return
}