HaikuDepot: Put supported languages into a StringList

* Added TODO to retrieve the list from the web-app, there is already an
  API for it. For now, the hard-coded list matches the web-app's and the
  next change in this regard will be to support any known language.
* Make the list accessible.

src/apps/haikudepot/model/Model.cpp

@@ -340,12 +340,22 @@ Model::Model()
 				language.CopyInto(fPreferredLanguage, 0, 2);
 		}
 	}
-	if (fPreferredLanguage != "en" && fPreferredLanguage != "de"
+
-		&& fPreferredLanguage != "fr" && fPreferredLanguage != "ja"
+	// TODO: Fetch this from the web-app.
-		&& fPreferredLanguage != "es" && fPreferredLanguage != "zh"
+	fSupportedLanguages.Add("en");
-		&& fPreferredLanguage != "pt" && fPreferredLanguage != "ru") {
+	fSupportedLanguages.Add("de");
+	fSupportedLanguages.Add("fr");
+	fSupportedLanguages.Add("ja");
+	fSupportedLanguages.Add("es");
+	fSupportedLanguages.Add("zh");
+	fSupportedLanguages.Add("pt");
+	fSupportedLanguages.Add("ru");
+
+	if (!fSupportedLanguages.Contains(fPreferredLanguage)) {
 		// Force the preferred language to one of the currently supported
 		// ones, until the web application supports all ISO language codes.
+		printf("User preferred language '%s' not currently supported, "
+			"defaulting to 'en'.", fPreferredLanguage.String());
 		fPreferredLanguage = "en";
 	}
 	fWebAppInterface.SetPreferredLanguage(fPreferredLanguage);

src/apps/haikudepot/model/Model.h

@@ -104,6 +104,9 @@ public:
 			void				PopulateAllPackages();
 			void				StopPopulatingAllPackages();
 
+			const StringList&	SupportedLanguages() const
+									{ return fSupportedLanguages; }
+
 			const BString&		PreferredLanguage() const
 									{ return fPreferredLanguage; }
 
@@ -175,6 +178,7 @@ private:
 			thread_id			fPopulateAllPackagesThread;
 	volatile bool				fStopPopulatingAllPackages;
 
+			StringList			fSupportedLanguages;
 			BString				fPreferredLanguage;
 
 			WebAppInterface		fWebAppInterface;