package cmd

import (
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"path/filepath"

	"github.com/gorilla/mux"
	"github.com/spf13/cobra"
)

var (
	serveAddress   string
	serveDirectory string
)

var serveCmd = &cobra.Command{
	Use:   "serve",
	Short: "Run a backup server",
	Long:  "Run an HTTP server to upload and download backups.",
	Run: func(cmd *cobra.Command, args []string) {
		if serveDirectory == "" {
			home, err := os.UserHomeDir()
			if err != nil {
				log.Fatalf("Failed to get user home directory: %v", err)
			}
			serveDirectory = filepath.Join(home, "backups")
		}

		if err := os.MkdirAll(serveDirectory, 0755); err != nil {
			log.Fatalf("Failed to create backup directory: %v", err)
		}

		r := mux.NewRouter()
		r.HandleFunc("/backup/{filename}", uploadHandler).Methods("POST")
		r.HandleFunc("/backup/{filename}", downloadHandler).Methods("GET")

		log.Printf("Starting server on %s", serveAddress)
		log.Printf("Using backup directory: %s", serveDirectory)
		if err := http.ListenAndServe(serveAddress, r); err != nil {
			log.Fatalf("Server failed: %v", err)
		}
	},
}

func uploadHandler(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	filename := vars["filename"]
	filePath := filepath.Join(serveDirectory, filename)

	file, err := os.Create(filePath)
	if err != nil {
		http.Error(w, "Failed to create file", http.StatusInternalServerError)
		log.Printf("Error creating file %s: %v", filename, err)
		return
	}
	defer file.Close()

	_, err = io.Copy(file, r.Body)
	if err != nil {
		http.Error(w, "Failed to write to file", http.StatusInternalServerError)
		log.Printf("Error writing to file %s: %v", filename, err)
		return
	}

	w.WriteHeader(http.StatusOK)
	fmt.Fprintf(w, "File %s uploaded successfully.", filename)
	log.Printf("Uploaded %s", filename)
}

func downloadHandler(w http.ResponseWriter, r *http.Request) {
	vars := mux.Vars(r)
	filename := vars["filename"]
	filePath := filepath.Join(serveDirectory, filename)

	// Проверяем, существует ли файл, перед отправкой
	if _, err := os.Stat(filePath); os.IsNotExist(err) {
		http.NotFound(w, r)
		log.Printf("File not found: %s", filename)
		return
	}

	// http.ServeFile - это идиоматический способ отправки файлов в Go.
	// Он автоматически устанавливает Content-Type, Content-Length и другие заголовки.
	http.ServeFile(w, r, filePath)
	log.Printf("Downloaded %s", filename)
}

func init() {
	rootCmd.AddCommand(serveCmd)
	serveCmd.Flags().StringVarP(&serveAddress, "address", "a", "localhost:8080", "Address and port for the server")
	serveCmd.Flags().StringVarP(&serveDirectory, "directory", "d", "", "Directory to store backups (defaults to ~/backups)")
}