From 07640dce698cce99488f9e3c00a90e7ffd5e2e4b Mon Sep 17 00:00:00 2001
From: Jiayan Zhuang <jiayan0406@fb.com>
Date: Thu, 6 Aug 2020 14:33:18 -0700
Subject: [PATCH] Build the basic RCTLocalizationProvider

Summary:
Changelog:
[Internal][Add] - Build the basic RCTLocalizationProvider

RCTLocalizationProvider is to enable the localization in fabric. But I'd start with internal apps now.

Reviewed By: PeteTheHeat

Differential Revision: D22704051

fbshipit-source-id: 845693a131c325f3c3d92b2ff491d5421966ad3e
---
 React/Fabric/RCTLocalizationProvider.h  | 36 ++++++++++++++++++++++
 React/Fabric/RCTLocalizationProvider.mm | 40 +++++++++++++++++++++++++
 2 files changed, 76 insertions(+)
 create mode 100644 React/Fabric/RCTLocalizationProvider.h
 create mode 100644 React/Fabric/RCTLocalizationProvider.mm

diff --git a/React/Fabric/RCTLocalizationProvider.h b/React/Fabric/RCTLocalizationProvider.h
new file mode 100644
index 00000000000..be98107c6f6
--- /dev/null
+++ b/React/Fabric/RCTLocalizationProvider.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <React/RCTDefines.h>
+#import <UIKit/UIKit.h>
+
+@protocol RCTLocalizationProtocol <NSObject>
+
+/*
+ Call for other apps to use their own translation functions
+ */
+- (NSString *)localizedString:(NSString *)oldString withDescription:(NSString *)description;
+
+@end
+
+/*
+ * It allows to set delegate for RCTLocalizationProvider so that we could ask APPs to do translations.
+ * It's an experimental feature.
+ */
+RCT_EXTERN void setLocalizationDelegate(id<RCTLocalizationProtocol> delegate);
+
+/*
+ * It allows apps to provide their translated language pack in case the cannot do translation reactively.
+ * It's an experimental feature.
+ */
+RCT_EXTERN void setLocalizationLanguagePack(NSDictionary<NSString *, NSString *> *pack);
+
+@interface RCTLocalizationProvider : NSObject
+
++ (NSString *)RCTLocalizedString:(NSString *)oldString withDescription:(NSString *)description;
+
+@end
diff --git a/React/Fabric/RCTLocalizationProvider.mm b/React/Fabric/RCTLocalizationProvider.mm
new file mode 100644
index 00000000000..4359af2527e
--- /dev/null
+++ b/React/Fabric/RCTLocalizationProvider.mm
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import "RCTLocalizationProvider.h"
+
+#import <Foundation/Foundation.h>
+
+static id<RCTLocalizationProtocol> _delegate = nil;
+static NSDictionary<NSString *, NSString *> *_languagePack = nil;
+
+void setLocalizationDelegate(id<RCTLocalizationProtocol> delegate)
+{
+  _delegate = delegate;
+}
+
+void setLocalizationLanguagePack(NSDictionary<NSString *, NSString *> *pack)
+{
+  _languagePack = pack;
+}
+
+@implementation RCTLocalizationProvider
+
++ (NSString *)RCTLocalizedString:(NSString *)oldString withDescription:(NSString *)description
+{
+  if (_delegate != nil) {
+    return [_delegate localizedString:oldString withDescription:description];
+  }
+
+  if (_languagePack != nil) {
+    return _languagePack[oldString];
+  }
+
+  return oldString;
+}
+
+@end