package main

import (
	"bufio"
	"fmt"
	"net/http"
	"os"
	"path/filepath"
	"runtime"
	"strings"

	"github.com/AlecAivazis/survey/v2"
	"github.com/AlecAivazis/survey/v2/terminal"
	"github.com/Masterminds/semver/v3"
	"github.com/fatih/color"
	"github.com/minio/selfupdate"
)

var UPDATEURL = "http://gozilla.fhi.mpg.de/goca"

// Color function variables matching tools.go in dns
var Crb func(...interface{}) string = color.New(color.Bold, color.FgRed).SprintFunc()
var Cgb func(...interface{}) string = color.New(color.Bold, color.FgGreen).SprintFunc()
var Cwb func(...interface{}) string = color.New(color.Bold, color.FgWhite).SprintFunc()

func SF(format string, a ...any) string {
	return fmt.Sprintf(format, a...)
}

func PE(msg ...string) (n int, err error) {
	if len(msg) == 2 {
		return fmt.Fprintf(os.Stdout, "%s: %s (%s)\n", Crb("ERROR"), Cwb(msg[0]), msg[1])
	}
	return fmt.Fprintf(os.Stdout, "%s: %s\n", Crb("ERROR"), Cwb(msg[0]))
}

func PO(msg ...string) (n int, err error) {
	if len(msg) == 2 {
		return fmt.Fprintf(os.Stdout, "%s: %s (%s)\n", Cgb("OK"), Cwb(msg[0]), msg[1])
	}
	return fmt.Fprintf(os.Stdout, "%s: %s\n", Cgb("OK"), Cwb(msg[0]))
}

func checkforupdate(URL string) { // ----------------------------------------------------- check for new version
	prg := prgname()
	resp, err := http.Get(URL + "/version.txt")
	if err == nil {
		scanner := bufio.NewScanner(resp.Body)
		if scanner.Scan() {
			lversion := strings.TrimSpace(scanner.Text())
			sv_version, err := semver.NewVersion(Version)
			if err == nil {
				sv_lversion, err := semver.NewVersion(lversion)
				if err == nil {
					if sv_lversion.GreaterThan(sv_version) {
						ans := Yesno(SF("new '%s' version found (%s -> %s), update now?",
							prg, sv_version, sv_lversion), true, false)
						if ans {
							updateurl := SF("%s/%s_%s_%s_%s", URL, prg, lversion, runtime.GOOS, runtime.GOARCH)

							if err := doupdate(updateurl); err != nil {
								PE(SF("Update failed: %v\n", err))
								os.Exit(1)
							}
							PO("Update successful!", "please run your last command again")
							os.Exit(0)
						}
					}
				}
			}
		}
		resp.Body.Close()
	}
}

func doupdate(url string) error { // ----------------------------------------------------------------- do update
	resp, err := http.Get(url)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("server returned status: %v", resp.Status)
	}
	err = selfupdate.Apply(resp.Body, selfupdate.Options{})
	if err != nil {
		return err
	}
	return nil
}

func Yesno(msg string, def bool, overwrite bool) bool { // -------------------------- AlecAivazis/survey: yes/no
	if overwrite {
		return true
	}

	var err error
	tmp := ""
	if def {
		err = survey.AskOne(&survey.Select{Message: msg, Options: []string{"Yes", "No"}}, &tmp)
	} else {
		err = survey.AskOne(&survey.Select{Message: msg, Options: []string{"No", "Yes"}}, &tmp)
	}

	if err != nil {
		if err == terminal.InterruptErr {
			fmt.Fprintln(os.Stdout, Crb("Interrupted."))
			os.Exit(0)
		}
	}

	if tmp == "Yes" {
		return true
	} else {
		return false
	}
}

func prgname() string { // ---------------------------------------------------------------- program name
	exepath, err := os.Executable()
	if err != nil {
		PE(SF("Error getting executable path: %s", err))
		return ""
	}
	exename := filepath.Base(exepath)
	return exename
}