From 96708d58e4b413032f4e5ffcc71e8da67ef99ea0 Mon Sep 17 00:00:00 2001
From: Jiayan Zhuang <jiayan0406@fb.com>
Date: Mon, 6 Jul 2020 14:58:38 -0700
Subject: [PATCH] Add getRectWithAttributedString() to RCTTextLayoutManager

Summary:
Changelog:
[iOS][Added] - `getRectWithAttributedString()` aims to get the rect of the fragment with embedded link, which is necessary when building the `accessibilityElement`. In this function, we first enumerate attributedString to find the range of fragments whose `accessibilityRole` is @"link". Then we calculate the rect of the fragment and send to the block and we would define what to do in the block in `RCTParagraphComponentAccessibilityProvider`.

Reviewed By: shergin

Differential Revision: D22286733

fbshipit-source-id: 4d11cb54375a4e9e72869e646fcb484de089b14b
---
 .../platform/ios/RCTTextLayoutManager.h       | 13 ++++++
 .../platform/ios/RCTTextLayoutManager.mm      | 40 +++++++++++++++++++
 2 files changed, 53 insertions(+)

diff --git a/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.h b/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.h
index 0e10ce2a085..eb495776e8c 100644
--- a/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.h
+++ b/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.h
@@ -15,6 +15,13 @@
 
 NS_ASSUME_NONNULL_BEGIN
 
+/**
+ @abstract Enumeration block for text fragments.
+*/
+
+using RCTTextLayoutFragmentEnumerationBlock =
+    void (^)(CGRect fragmentRect, NSString *_Nonnull fragmentText, NSString *value);
+
 /**
  * iOS-specific TextLayoutManager
  */
@@ -38,6 +45,12 @@ NS_ASSUME_NONNULL_BEGIN
                                  frame:(CGRect)frame
                                atPoint:(CGPoint)point;
 
+- (void)getRectWithAttributedString:(facebook::react::AttributedString)attributedString
+                paragraphAttributes:(facebook::react::ParagraphAttributes)paragraphAttributes
+                 enumerateAttribute:(NSString *)enumerateAttribute
+                              frame:(CGRect)frame
+                         usingBlock:(RCTTextLayoutFragmentEnumerationBlock)block;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.mm b/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.mm
index 7e0c4a9231a..de6e354aa55 100644
--- a/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.mm
+++ b/ReactCommon/fabric/textlayoutmanager/platform/ios/RCTTextLayoutManager.mm
@@ -182,4 +182,44 @@ static NSLineBreakMode RCTNSLineBreakModeFromEllipsizeMode(EllipsizeMode ellipsi
   return unwrapManagedObject(sharedNSAttributedString);
 }
 
+- (void)getRectWithAttributedString:(AttributedString)attributedString
+                paragraphAttributes:(ParagraphAttributes)paragraphAttributes
+                 enumerateAttribute:(NSString *)enumerateAttribute
+                              frame:(CGRect)frame
+                         usingBlock:(RCTTextLayoutFragmentEnumerationBlock)block
+{
+  NSTextStorage *textStorage = [self
+      _textStorageAndLayoutManagerWithAttributesString:[self _nsAttributedStringFromAttributedString:attributedString]
+                                   paragraphAttributes:paragraphAttributes
+                                                  size:frame.size];
+
+  NSLayoutManager *layoutManager = textStorage.layoutManagers.firstObject;
+  NSTextContainer *textContainer = layoutManager.textContainers.firstObject;
+  [layoutManager ensureLayoutForTextContainer:textContainer];
+
+  NSRange glyphRange = [layoutManager glyphRangeForTextContainer:textContainer];
+  NSRange characterRange = [layoutManager characterRangeForGlyphRange:glyphRange actualGlyphRange:NULL];
+
+  [textStorage enumerateAttribute:enumerateAttribute
+                          inRange:characterRange
+                          options:0
+                       usingBlock:^(NSString *value, NSRange range, BOOL *pause) {
+                         if (!value) {
+                           return;
+                         }
+
+                         [layoutManager
+                             enumerateEnclosingRectsForGlyphRange:range
+                                         withinSelectedGlyphRange:range
+                                                  inTextContainer:textContainer
+                                                       usingBlock:^(CGRect enclosingRect, BOOL *_Nonnull stop) {
+                                                         block(
+                                                             enclosingRect,
+                                                             [textStorage attributedSubstringFromRange:range].string,
+                                                             value);
+                                                         *stop = YES;
+                                                       }];
+                       }];
+}
+
 @end