feat: totps - show remaining time (#12)

internal/andotp.go

@@ -102,11 +102,10 @@ func Decrypt(password, text []byte) ([]byte, error) {
 
 type Entry struct {
 	Algorithm string   `json:"algorithm"`
-	Digits    uint     `json:"digits"`
+	Digits    uint8    `json:"digits"`
 	Issuer    string   `json:"issuer"`
 	Label     string   `json:"label"`
-	LastUsed  int64    `json:"last_used"`
-	Period    uint     `json:"period"`
+	Period    uint32   `json:"period"`
 	Secret    string   `json:"secret"`
 	Tags      []string `json:"tags"`
 	Thumbnail string   `json:"thumbnail"`

internal/andotp_test.go

@@ -3,7 +3,6 @@ package internal_test
 import (
 	"encoding/json"
 	"testing"
-	"time"
 
 	"github.com/Kichiyaki/gootp/internal"
 
@@ -19,7 +18,6 @@ func TestEncryptDecrypt(t *testing.T) {
 			Digits:    6,
 			Issuer:    "TestIssuer",
 			Label:     "TestLabel",
-			LastUsed:  time.Now().Unix(),
 			Period:    30,
 			Secret:    "secret",
 			Thumbnail: "Default",

internal/otp.go

@@ -9,30 +9,31 @@ import (
 	"github.com/pquerna/otp/totp"
 )
 
-func GenerateOTP(entry Entry, t time.Time) (string, error) {
+func GenerateOTP(entry Entry, t time.Time) (string, int64, error) {
 	algorithm, err := parseAlgorithm(entry.Algorithm)
 	if err != nil {
-		return "", fmt.Errorf("parseAlgorithm: %w", err)
+		return "", 0, fmt.Errorf("parseAlgorithm: %w", err)
 	}
 
 	digits, err := parseDigits(entry.Digits)
 	if err != nil {
-		return "", fmt.Errorf("parseDigits: %w", err)
+		return "", 0, fmt.Errorf("parseDigits: %w", err)
 	}
 
 	switch strings.ToUpper(entry.Type) {
 	case "TOTP":
 		code, err := totp.GenerateCodeCustom(entry.Secret, t, totp.ValidateOpts{
 			Algorithm: algorithm,
-			Period:    entry.Period,
+			Period:    uint(entry.Period),
 			Digits:    digits,
 		})
 		if err != nil {
-			return "", fmt.Errorf("something went wrong while generating totp: %w", err)
+			return "", 0, fmt.Errorf("something went wrong while generating totp: %w", err)
 		}
-		return code, nil
+		period := int64(entry.Period)
+		return code, period - (t.Unix() % period), nil
 	default:
-		return "", fmt.Errorf("unsupported entry type: %s", entry.Type)
+		return "", 0, fmt.Errorf("unsupported entry type: %s", entry.Type)
 	}
 }
 
@@ -51,7 +52,7 @@ func parseAlgorithm(algorithm string) (otp.Algorithm, error) {
 	}
 }
 
-func parseDigits(digits uint) (otp.Digits, error) {
+func parseDigits(digits uint8) (otp.Digits, error) {
 	switch digits {
 	case 6:
 		return otp.DigitsSix, nil

internal/ui.go

@@ -1,6 +1,7 @@
 package internal
 
 import (
+	"fmt"
 	"time"
 
 	"github.com/charmbracelet/bubbles/list"
@@ -87,21 +88,25 @@ func (ui UI) tick() tea.Cmd {
 func entriesToItems(entries []Entry, t time.Time) []list.Item {
 	items := make([]list.Item, len(entries))
 	for i, e := range entries {
-		title := e.Label
-		if e.Issuer != "" {
-			title = e.Issuer + " - " + e.Label
-		}
-
-		otp, err := GenerateOTP(e, t)
-		description := otp
-		if err != nil {
-			description = err.Error()
-		}
-
 		items[i] = item{
-			title:       title,
-			description: description,
+			title:       buildItemTitle(e.Issuer, e.Label),
+			description: buildItemDescription(e, t),
 		}
 	}
 	return items
 }
+
+func buildItemTitle(issuer, label string) string {
+	if issuer != "" {
+		return issuer + " - " + label
+	}
+	return label
+}
+
+func buildItemDescription(e Entry, t time.Time) string {
+	otp, remaining, err := GenerateOTP(e, t)
+	if err != nil {
+		return err.Error()
+	}
+	return fmt.Sprintf("%s - %d", otp, remaining)
+}