package main

import (
	"bufio"
	"fmt"
	"github.com/jlaffaye/ftp"
	"io/ioutil"
	"log"
	"net/http"
	"os"
)

var (
	Server = "185.20.227.83:9212"
	Login = "admin"
	Password = "123456"
	BasePath = "/home/iu9_33_03/GoProjects/src/Laba1"
	client *ftp.ServerConn
	file *os.File
	err error
	cur1, _ = ioutil.ReadFile("web/Home.html")
	homeScreenForm = string(cur1)
	cur2, _ = ioutil.ReadFile("web/Menu.html")
	menuScreenFormStart = string(cur2)
	cur3, _ = ioutil.ReadFile("web/Options.html")
	options = string(cur3)
	cur4, _ = ioutil.ReadFile("web/End.html")
	menuScreenFormEnd = string(cur4)
)

func HomeScreenHandler(w http.ResponseWriter, r *http.Request) {
	fmt.Fprintf(w, homeScreenForm)
}

func MenuScreenHandler(w http.ResponseWriter, r *http.Request) {
	/*
	if r.URL.Query().Get("server") != "" {
		Server = r.URL.Query().Get("server")
	}
	if r.URL.Query().Get("login") != "" {
		Login = r.URL.Query().Get("login")
	}
	if r.URL.Query().Get("pass") != "" {
		Password = r.URL.Query().Get("pass")
	}
	*/

	res := menuScreenFormStart
	res += "<center><p><h2>" + Server + "</h2></p>" + "<p><h3> Connected </h3></p>"
	res += options
	option := r.URL.Query().Get("options")

	switch option {
	case "delete":
		err = removeDirectory(r.URL.Query().Get("f1"))
		if err != nil {
			log.Fatal(err)
		}
	case "make":
		err = makeDirectory(r.URL.Query().Get("f1"))
		if err != nil {
			log.Fatal(err)
		}
	case "list":
		entries, err := listOfDirectories(r.URL.Query().Get("f1"))
		if err != nil {
			log.Fatal(err)
		}
		res += "<p><b>" + r.URL.Query().Get("f1") + ": </b></p>"
		for _, e := range entries {
			res += "<p>" + e.Name + "</p>"
		}
	case "upload":
		err = uploadFile(r.URL.Query().Get("f1"), r.URL.Query().Get("f2"))
		if err != nil {
			log.Fatal(err)
		}
	case "read":
		str, err := readFile(r.URL.Query().Get("f1"))
		if err != nil {
			log.Fatal(err)
		}
		res += "<p>" + str + "</p>"
	case "currentDir":
		str, err := currentDirectory()
		if err != nil {
			log.Fatal(err)
		}
		res += "<p>" + str + "</p>"
	case "change":
		err := changeDirectory(r.URL.Query().Get("f1"))
		if err != nil {
			log.Fatal(err)
		}
	}
	res += menuScreenFormEnd
	fmt.Fprint(w, res)
}

func uploadFile(from string, to string) error {
	file, err = os.Open(BasePath + from)
	if err != nil {
		return err
	}
	reader := bufio.NewReader(file)
	err = client.Stor(to, reader)
	if err != nil {
		return err
	}
	return nil
}

func removeDirectory(path string) error {
	err = client.Delete(path)
	if err != nil {
		return err
	}
	return nil
}

func makeDirectory(dir string) error {
	err = client.MakeDir(dir)
	if err != nil {
		return err
	}
	return nil
}

func listOfDirectories(path string) ([]*ftp.Entry, error) {
	entries, err := client.List(path)
	if err != nil {
		return nil, err
	}
	return entries, nil
}

func readFile(path string) (string, error) {
	file, err := client.Retr(path)
	if err != nil {
		return "", err
	}
	buffer, err := ioutil.ReadAll(file)
	if err != nil {
		return "", err
	}
	return string(buffer), nil
}

func currentDirectory() (string, error) {
	name, err := client.CurrentDir()
	if err != nil {
		return "", err
	}
	return name, nil
}

func changeDirectory(path string) error {
	err = client.ChangeDir(path)
	if err != nil {
		return err
	}
	return nil
}

func main() {
	client, err = ftp.Connect(Server)
	if err != nil {
		log.Fatal(err)
	}
	err = client.Login(Login, Password)
	if err != nil {
		log.Fatal(err)
	}
	http.HandleFunc("/", HomeScreenHandler)
	http.HandleFunc("/menu", MenuScreenHandler)
	err = http.ListenAndServe(":9212", nil)
	if err != nil {
		log.Fatal("ListenAndServe: ", err)
	}
	err = client.Quit()
	if err != nil {
		log.Fatal(err)
	}
}