[ios, macos] Allow specifying multiple fonts or font families for loc…

…al font rendering

Removed MGLIdeographicFontFamilyName validation from MGLRendererConfiguration, since mbgl::LocalGlyphRasterizer performs more robust validation. Removed C++ from MGLRendererConfiguration interface, implementation, and tests for simplicity.

Pass all the specified font and font family names into mbgl so that mbgl::LocalGlyphRasterizer can form a full font cascade list.

platform/darwin/src/MGLMapSnapshotter.mm

@@ -725,9 +725,10 @@ - (void)configureWithOptions:(MGLMapSnapshotOptions *)options {
                    .withAssetPath(NSBundle.mainBundle.resourceURL.path.UTF8String);
 
     // Create the snapshotter
+    auto localFontFamilyName = config.localFontFamilyName ? std::string(config.localFontFamilyName.UTF8String) : nullptr;
     _delegateHost = std::make_unique<MGLMapSnapshotterDelegateHost>(self);
     _mbglMapSnapshotter = std::make_unique<mbgl::MapSnapshotter>(
-                                                                 size, pixelRatio, resourceOptions, *_delegateHost, config.localFontFamilyName);
+                                                                 size, pixelRatio, resourceOptions, *_delegateHost, localFontFamilyName);
 
     _mbglMapSnapshotter->setStyleURL(std::string(options.styleURL.absoluteString.UTF8String));
 

platform/darwin/src/MGLRendererConfiguration.h

@@ -1,8 +1,6 @@
 #import "MGLFoundation.h"
 #import <Foundation/Foundation.h>
 
-#include <mbgl/util/optional.hpp>
-
 NS_ASSUME_NONNULL_BEGIN
 
 /**
@@ -34,7 +32,9 @@ MGL_EXPORT
  - A boolean value NO to disable client-side rendering of CJK glyphs —
  remote fonts specified in your style will be used instead.
  */
-@property (nonatomic, readonly) mbgl::optional<std::string> localFontFamilyName;
+@property (nonatomic, readonly, nullable) NSString *localFontFamilyName;
+
+- (nullable NSString *)localFontFamilyNameWithInfoDictionaryObject:(nullable id)infoDictionaryObject;
 
 /**
  A Boolean value indicating whether symbol layers may enable per-source symbol
@@ -49,6 +49,8 @@ MGL_EXPORT
  */
 @property (nonatomic, readonly) BOOL perSourceCollisions;
 
+- (BOOL)perSourceCollisionsWithInfoDictionaryObject:(nullable id)infoDictionaryObject;
+
 @end
 
 NS_ASSUME_NONNULL_END

platform/darwin/src/MGLRendererConfiguration.m

@@ -0,0 +1,66 @@
+#import "MGLRendererConfiguration.h"
+
+#if TARGET_OS_IPHONE
+#import <UIKit/UIKit.h>
+#else
+#import <AppKit/AppKit.h>
+#endif
+
+static NSString * const MGLCollisionBehaviorPre4_0Key = @"MGLCollisionBehaviorPre4_0";
+static NSString * const MGLIdeographicFontFamilyNameKey = @"MGLIdeographicFontFamilyName";
+
+@implementation MGLRendererConfiguration
+
++ (instancetype)currentConfiguration {
+    return [[self alloc] init];
+}
+
+- (const float)scaleFactor {
+#if TARGET_OS_IPHONE
+    return [UIScreen instancesRespondToSelector:@selector(nativeScale)] ? [[UIScreen mainScreen] nativeScale] : [[UIScreen mainScreen] scale];
+#else
+    return [NSScreen mainScreen].backingScaleFactor;
+#endif
+}
+
+- (nullable NSString *)localFontFamilyName {
+    id infoDictionaryObject = [NSBundle.mainBundle objectForInfoDictionaryKey:MGLIdeographicFontFamilyNameKey];
+    return [self localFontFamilyNameWithInfoDictionaryObject:infoDictionaryObject];
+}
+
+- (nullable NSString *)localFontFamilyNameWithInfoDictionaryObject:(nullable id)infoDictionaryObject {
+    if ([infoDictionaryObject isKindOfClass:[NSNumber class]] && ![infoDictionaryObject boolValue]) {
+        // NO means don’t use local fonts.
+        return nil;
+    } else if ([infoDictionaryObject isKindOfClass:[NSString class]]) {
+        return infoDictionaryObject;
+    } else if ([infoDictionaryObject isKindOfClass:[NSArray class]]) {
+        // mbgl::LocalGlyphRasterizer::Impl accepts only a single string, but form a cascade list with one font on each line.
+        return [infoDictionaryObject componentsJoinedByString:@"\n"];
+    }
+
+#if TARGET_OS_IPHONE
+    return [UIFont systemFontOfSize:0 weight:UIFontWeightRegular].familyName;
+#else
+    return [NSFont systemFontOfSize:0 weight:NSFontWeightRegular].familyName;
+#endif
+}
+
+- (BOOL)perSourceCollisions {
+    id infoDictionaryObject = [NSBundle.mainBundle objectForInfoDictionaryKey:MGLCollisionBehaviorPre4_0Key];
+    return [self perSourceCollisionsWithInfoDictionaryObject:infoDictionaryObject];
+}
+
+- (BOOL)perSourceCollisionsWithInfoDictionaryObject:(nullable id)infoDictionaryObject {
+    // Set the collision behaviour. A value set in `NSUserDefaults.standardUserDefaults`
+    // should override anything in the application's info.plist
+    if ([NSUserDefaults.standardUserDefaults objectForKey:MGLCollisionBehaviorPre4_0Key]) {
+        return [NSUserDefaults.standardUserDefaults boolForKey:MGLCollisionBehaviorPre4_0Key];
+    } else if ([infoDictionaryObject isKindOfClass:[NSNumber class]] || [infoDictionaryObject isKindOfClass:[NSString class]]) {
+        // Also support NSString to correspond with the behavior of `-[NSUserDefaults boolForKey:]`
+        return [infoDictionaryObject boolValue];
+    }
+    return NO;
+}
+
+@end

platform/darwin/test/MGLRendererConfigurationTests.m

@@ -0,0 +1,162 @@
+#import <Mapbox/Mapbox.h>
+#import <XCTest/XCTest.h>
+#import "MGLRendererConfiguration.h"
+
+static NSString * const MGLRendererConfigurationTests_collisionBehaviorKey = @"MGLCollisionBehaviorPre4_0";
+
+@interface MGLRendererConfigurationTests : XCTestCase
+@end
+
+@implementation MGLRendererConfigurationTests
+- (void)setUp {
+    [[NSUserDefaults standardUserDefaults] removeObjectForKey:MGLRendererConfigurationTests_collisionBehaviorKey];
+}
+
+- (void)tearDown {
+    [[NSUserDefaults standardUserDefaults] removeObjectForKey:MGLRendererConfigurationTests_collisionBehaviorKey];
+}
+
+// Emulate what would happen with an Info.plist.
+- (void)testSettingMGLCollisionBehaviorPre40
+{
+    MGLRendererConfiguration *config = [[MGLRendererConfiguration alloc] init];
+    XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:nil]);
+    XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:@(NO)]);
+    XCTAssertTrue([config perSourceCollisionsWithInfoDictionaryObject:@(YES)]);
+    XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:@"NO"]);
+    XCTAssertTrue([config perSourceCollisionsWithInfoDictionaryObject:@"YES"]);
+}
+
+- (void)testSettingMGLCollisionBehaviorPre40InNSUserDefaults {
+    {
+        XCTAssertNil([[NSUserDefaults standardUserDefaults] objectForKey:MGLRendererConfigurationTests_collisionBehaviorKey]);
+        MGLRendererConfiguration *config = [MGLRendererConfiguration currentConfiguration];
+        XCTAssertFalse(config.perSourceCollisions);
+        XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:nil]);
+    }
+
+    [[NSUserDefaults standardUserDefaults] setObject:@(NO) forKey:MGLRendererConfigurationTests_collisionBehaviorKey];
+    {
+        XCTAssertNotNil([[NSUserDefaults standardUserDefaults] objectForKey:MGLRendererConfigurationTests_collisionBehaviorKey]);
+        MGLRendererConfiguration *config = [MGLRendererConfiguration currentConfiguration];
+        XCTAssertFalse(config.perSourceCollisions);
+        XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:@(NO)]);
+        XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:@(YES)]);
+    }
+
+    [[NSUserDefaults standardUserDefaults] setObject:@(YES) forKey:MGLRendererConfigurationTests_collisionBehaviorKey];
+    {
+        XCTAssertNotNil([[NSUserDefaults standardUserDefaults] objectForKey:MGLRendererConfigurationTests_collisionBehaviorKey]);
+        MGLRendererConfiguration *config = [MGLRendererConfiguration currentConfiguration];
+        XCTAssert(config.perSourceCollisions);
+        XCTAssertTrue([config perSourceCollisionsWithInfoDictionaryObject:@(NO)]);
+        XCTAssertTrue([config perSourceCollisionsWithInfoDictionaryObject:@(YES)]);
+    }
+}
+
+- (void)testOverridingMGLCollisionBehaviorPre40 {
+    // Dictionary = NO, NSUserDefaults = YES
+    {
+        [[NSUserDefaults standardUserDefaults] setObject:@(YES) forKey:MGLRendererConfigurationTests_collisionBehaviorKey];
+        MGLRendererConfiguration *config = [[MGLRendererConfiguration alloc] init];
+        XCTAssert([config perSourceCollisionsWithInfoDictionaryObject:@(NO)]);
+    }
+    // Dictionary = YES, NSUserDefaults = NO
+    {
+        [[NSUserDefaults standardUserDefaults] setObject:@(NO) forKey:MGLRendererConfigurationTests_collisionBehaviorKey];
+        MGLRendererConfiguration *config = [[MGLRendererConfiguration alloc] init];
+        XCTAssertFalse([config perSourceCollisionsWithInfoDictionaryObject:@(YES)]);
+    }
+}
+
+- (void)testDefaultLocalFontFamilyName {
+
+    MGLRendererConfiguration *config = [[MGLRendererConfiguration alloc] init];
+    NSString *localFontFamilyName = config.localFontFamilyName;
+
+    NSString *systemFontFamilyName;
+#if TARGET_OS_IPHONE
+    systemFontFamilyName = [UIFont systemFontOfSize:0 weight:UIFontWeightRegular].familyName;
+#else
+    systemFontFamilyName = [NSFont systemFontOfSize:0 weight:NSFontWeightRegular].familyName;
+#endif
+
+    XCTAssertEqualObjects(localFontFamilyName, systemFontFamilyName, @"Default local font family name should match default system font");
+}
+
+- (void)testSettingMGLIdeographicFontFamilyNameWithPlistValue {
+
+    MGLRendererConfiguration *config = [[MGLRendererConfiguration alloc] init];
+
+    // `MGLIdeographicFontFamilyName` set to bool value `YES`
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:@(YES)];
+
+        NSString *systemFontFamilyName;
+#if TARGET_OS_IPHONE
+        systemFontFamilyName = [UIFont systemFontOfSize:0 weight:UIFontWeightRegular].familyName;
+#else
+        systemFontFamilyName = [NSFont systemFontOfSize:0 weight:NSFontWeightRegular].familyName;
+#endif
+        XCTAssertEqualObjects(localFontFamilyName, systemFontFamilyName, @"Local font family name should match default system font name when setting `YES`");
+    }
+
+    // `MGLIdeographicFontFamilyName` set to bool value `NO`
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:@(NO)];
+        XCTAssertNil(localFontFamilyName, @"Client rendering font should use remote font when setting `NO`");
+    }
+
+    // `MGLIdeographicFontFamilyName` set to a valid font string value
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:@"PingFang TC"];
+        XCTAssertEqualObjects(localFontFamilyName, @"PingFang TC", @"Local font family name should match a custom valid font name");
+    }
+
+    // `MGLIdeographicFontFamilyName` set to an invalid font string value
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:@"test font"];
+
+        NSString *systemFontFamilyName;
+#if TARGET_OS_IPHONE
+        systemFontFamilyName = [UIFont systemFontOfSize:0 weight:UIFontWeightRegular].familyName;
+#else
+        systemFontFamilyName = [NSFont systemFontOfSize:0 weight:NSFontWeightRegular].familyName;
+#endif
+        XCTAssertNotEqualObjects(localFontFamilyName, systemFontFamilyName, @"Local font family name should not be validated by MGLRenderConfiguration");
+    }
+
+    // `MGLIdeographicFontFamilyName` set to a valid font family names array value
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:@[@"test font 1", @"PingFang TC", @"test font 2"]];
+        XCTAssertEqualObjects(localFontFamilyName, @"test font 1\nPingFang TC\ntest font 2");
+    }
+
+    // `MGLIdeographicFontFamilyName` set to an invalid font family names array value
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:@[@"test font 1", @"test font 2", @"test font 3"]];
+
+        NSString *systemFontFamilyName;
+#if TARGET_OS_IPHONE
+        systemFontFamilyName = [UIFont systemFontOfSize:0 weight:UIFontWeightRegular].familyName;
+#else
+        systemFontFamilyName = [NSFont systemFontOfSize:0 weight:NSFontWeightRegular].familyName;
+#endif
+        XCTAssertEqualObjects(localFontFamilyName, @"test font 1\ntest font 2\ntest font 3", @"Local font family name should not be validated by MGLRendererConfiguration");
+    }
+
+    // `MGLIdeographicFontFamilyName` set to an invalid value type: NSDictionary, NSNumber, NSData, etc.
+    {
+        NSString *localFontFamilyName = [config localFontFamilyNameWithInfoDictionaryObject:[@"test font 1" dataUsingEncoding:NSUTF8StringEncoding]];
+
+        NSString *systemFontFamilyName;
+#if TARGET_OS_IPHONE
+        systemFontFamilyName = [UIFont systemFontOfSize:0 weight:UIFontWeightRegular].familyName;
+#else
+        systemFontFamilyName = [NSFont systemFontOfSize:0 weight:NSFontWeightRegular].familyName;
+#endif
+        XCTAssertEqualObjects(localFontFamilyName, systemFontFamilyName, @"Local font family name should match default system font name when setting an invalid value type");
+    }
+}
+
+@end