[ios, macos] More robust Streets localization

Added Arabic, Portuguese, and Simplified Chinese to the list of languages with specialized fields in the Mapbox Streets source.

Rely on NSBundle to select the most appropriate locale based on the user’s preferred languages.

1 files changed, 11 insertions, 7 deletions

diff --git a/platform/macos/app/MGLVectorSource+MBXAdditions.m b/platform/macos/app/MGLVectorSource+MBXAdditions.m
index 644b43a651..323bc74366 100644
--- a/platform/macos/app/MGLVectorSource+MBXAdditions.m
+++ b/platform/macos/app/MGLVectorSource+MBXAdditions.m
@@ -7,19 +7,23 @@
     static dispatch_once_t onceToken;
     static NS_SET_OF(NSString *) *mapboxStreetsLanguages;
     dispatch_once(&onceToken, ^{
-        mapboxStreetsLanguages = [NSSet setWithObjects:@"en", @"es", @"fr", @"de", @"ru", @"zh", nil];
+        // https://www.mapbox.com/vector-tiles/mapbox-streets-v7/#overview
+        mapboxStreetsLanguages = [NSSet setWithObjects:@"ar", @"de", @"en", @"es", @"fr", @"pt", @"ru", @"zh", @"zh-Hans", nil];
     });
     return mapboxStreetsLanguages;
 }
 
-+ (nullable NSString *)preferredMapboxStreetsLanguage {
-    for (NSString *language in [NSLocale preferredLanguages]) {
-        NSString *languageCode = [[NSLocale localeWithLocaleIdentifier:language] objectForKey:NSLocaleLanguageCode];
-        if ([[MGLVectorSource mapboxStreetsLanguages] containsObject:languageCode]) {
-            return languageCode;
++ (NSString *)preferredMapboxStreetsLanguage {
+    NSArray<NSString *> *supportedLanguages = [MGLVectorSource mapboxStreetsLanguages].allObjects;
+    NSArray<NSString *> *preferredLanguages = [NSBundle preferredLocalizationsFromArray:supportedLanguages
+                                                                         forPreferences:[NSLocale preferredLanguages]];
+    NSString *mostSpecificLanguage;
+    for (NSString *language in preferredLanguages) {
+        if (language.length > mostSpecificLanguage.length) {
+            mostSpecificLanguage = language;
         }
     }
-    return nil;
+    return mostSpecificLanguage ?: @"en";
 }
 
 - (BOOL)isMapboxStreets {