fix(mal): distinguish silent token refresh from a fresh re-login

Two MAL login issues were caused by the refresh path being conflated
with the full browser OAuth flow:

1. A spurious 'It is now safe to close your browser tab' dialog was
   shown after a *silent* background token refresh, even though the
   browser was never opened. The dialog now belongs only to the
   browser-callback handler (handleMyAnimeListCallback); the refresh
   raises no dialog.

2. When both the access token and the refresh token were invalid, the
   app reported MAL as logged in without a username. Now, if a refresh
   fails (HttpClient error, non-2xx, or an empty access token), the
   stale tokens are cleared and a fresh browser OAuth login is
   automatically initiated instead of silently returning an empty user.

refreshMyAnimeListAuthorizationToken now returns a bool indicating
whether a fresh access token was actually obtained, letting
GetMyAnimeListLoggedInUser decide between retrying with the refreshed
token or falling back to a full re-login.

MALUserFunctions.go

@@ -235,7 +235,7 @@ func getMyAnimeListAuthorizationToken(content string, verifier *CodeVerifier) My
 	return post
 }
 
-func refreshMyAnimeListAuthorizationToken() {
+func refreshMyAnimeListAuthorizationToken() bool {
 	dataForURLs := struct {
 		GrantType    string `json:"grant_type"`
 		RefreshToken string `json:"refresh_token"`
@@ -260,13 +260,15 @@ func refreshMyAnimeListAuthorizationToken() {
 	response, err := http.NewRequest("POST", "https://myanimelist.net/v1/oauth2/token", strings.NewReader(data.Encode()))
 	if err != nil {
 		log.Printf("Failed at response, %s\n", err)
+		return false
 	}
 	response.Header.Add("Content-Type", "application/x-www-form-urlencoded")
 
 	client := &http.Client{}
 	res, resErr := client.Do(response)
 	if resErr != nil {
-		log.Printf("Failed at res, %s\n", err)
+		log.Printf("Failed at res, %s\n", resErr)
+		return false
 	}
 
 	defer res.Body.Close()
@@ -274,13 +276,22 @@ func refreshMyAnimeListAuthorizationToken() {
 	returnedBody, err := io.ReadAll(res.Body)
 	if err != nil {
 		log.Printf("Could not read returned body, %s\n", err)
+		return false
 	}
 
-	err = json.Unmarshal(returnedBody, &myAnimeListJwt)
+	var refreshed MyAnimeListJWT
+	err = json.Unmarshal(returnedBody, &refreshed)
 	if err != nil {
 		log.Printf("Failed at unmarshal, %s\n", err)
+		return false
 	}
 
+	if refreshed.AccessToken == "" {
+		return false
+	}
+
+	myAnimeListJwt = refreshed
+
 	_ = myAnimeListRing.Set(keyring.Item{
 		Key:  "MyAnimeListTokenType",
 		Data: []byte(myAnimeListJwt.TokenType),
@@ -297,26 +308,33 @@ func refreshMyAnimeListAuthorizationToken() {
 		Key:  "MyAnimeListRefreshToken",
 		Data: []byte(myAnimeListJwt.RefreshToken),
 	})
-	_, err = runtime.MessageDialog(*wailsContext, runtime.MessageDialogOptions{
-		Title:   "MyAnimeList Authorization",
-		Message: "It is now safe to close your browser tab",
-	})
-	if err != nil {
-		fmt.Println(err)
-	}
+	return true
 }
 
 func (a *App) GetMyAnimeListLoggedInUser() MyAnimeListUser {
 	a.MyAnimeListLogin()
 	user := createUser()
-	if user.Name == "" {
-		refreshMyAnimeListAuthorizationToken()
+	if user.Name == "" && !a.refreshMyAnimeListAndGetUser(&user) {
+		a.LogoutMyAnimeList()
+		a.MyAnimeListLogin()
 		user = createUser()
 	}
 
 	return user
 }
 
+func (a *App) refreshMyAnimeListAndGetUser(user *MyAnimeListUser) bool {
+	if !refreshMyAnimeListAuthorizationToken() {
+		return false
+	}
+	freshUser := createUser()
+	if freshUser.Name == "" {
+		return false
+	}
+	*user = freshUser
+	return true
+}
+
 func createUser() MyAnimeListUser {
 	client := &http.Client{}