Shuffle & Cleanup Stuff (#3080)

Source/TextKit/ASTextKitRenderer+TextChecking.mm

@@ -0,0 +1,101 @@
+//
+//  ASTextKitRenderer+TextChecking.mm
+//  AsyncDisplayKit
+//
+//  Copyright (c) 2014-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under the BSD-style license found in the
+//  LICENSE file in the root directory of this source tree. An additional grant
+//  of patent rights can be found in the PATENTS file in the same directory.
+//
+
+#import <AsyncDisplayKit/ASTextKitRenderer+TextChecking.h>
+
+#import <AsyncDisplayKit/ASTextKitEntityAttribute.h>
+#import <AsyncDisplayKit/ASTextKitRenderer+Positioning.h>
+#import <AsyncDisplayKit/ASTextKitTailTruncater.h>
+
+@implementation ASTextKitTextCheckingResult
+
+{
+  // Be explicit about the fact that we are overriding the super class' implementation of -range and -resultType
+  // and substituting our own custom values. (We could use @synthesize to make these ivars, but our linter correctly
+  // complains; it's weird to use @synthesize for properties that are redeclared on top of an original declaration in
+  // the superclass. We only do it here because NSTextCheckingResult doesn't expose an initializer, which is silly.)
+  NSRange _rangeOverride;
+  NSTextCheckingType _resultTypeOverride;
+}
+
+- (instancetype)initWithType:(NSTextCheckingType)type
+             entityAttribute:(ASTextKitEntityAttribute *)entityAttribute
+                       range:(NSRange)range
+{
+  if ((self = [super init])) {
+    _resultTypeOverride = type;
+    _rangeOverride = range;
+    _entityAttribute = entityAttribute;
+  }
+  return self;
+}
+
+- (NSTextCheckingType)resultType
+{
+  return _resultTypeOverride;
+}
+
+- (NSRange)range
+{
+  return _rangeOverride;
+}
+
+@end
+
+@implementation ASTextKitRenderer (TextChecking)
+
+- (NSTextCheckingResult *)textCheckingResultAtPoint:(CGPoint)point
+{
+  __block NSTextCheckingResult *result = nil;
+  NSAttributedString *attributedString = self.attributes.attributedString;
+  NSAttributedString *truncationAttributedString = self.attributes.truncationAttributedString;
+
+  // get the index of the last character, so we can handle text in the truncation token
+  __block NSRange truncationTokenRange = { NSNotFound, 0 };
+
+  [truncationAttributedString enumerateAttribute:ASTextKitTruncationAttributeName inRange:NSMakeRange(0, truncationAttributedString.length)
+                                         options:0
+                                      usingBlock:^(id value, NSRange range, BOOL *stop) {
+    if (value != nil && range.length > 0) {
+      truncationTokenRange = range;
+    }
+  }];
+
+  if (truncationTokenRange.location == NSNotFound) {
+    // The truncation string didn't specify a substring which should be highlighted, so we just highlight it all
+    truncationTokenRange = { 0, truncationAttributedString.length };
+  }
+
+  NSRange visibleRange = self.truncater.firstVisibleRange;
+  truncationTokenRange.location += NSMaxRange(visibleRange);
+  
+  __block CGFloat minDistance = CGFLOAT_MAX;
+  [self enumerateTextIndexesAtPosition:point usingBlock:^(NSUInteger index, CGRect glyphBoundingRect, BOOL *stop){
+    if (index >= truncationTokenRange.location) {
+      result = [[ASTextKitTextCheckingResult alloc] initWithType:ASTextKitTextCheckingTypeTruncation
+                                                 entityAttribute:nil
+                                                           range:truncationTokenRange];
+    } else {
+      NSRange range;
+      NSDictionary *attributes = [attributedString attributesAtIndex:index effectiveRange:&range];
+      ASTextKitEntityAttribute *entityAttribute = attributes[ASTextKitEntityAttributeName];
+      CGFloat distance = hypot(CGRectGetMidX(glyphBoundingRect) - point.x, CGRectGetMidY(glyphBoundingRect) - point.y);
+      if (entityAttribute && distance < minDistance) {
+        result = [[ASTextKitTextCheckingResult alloc] initWithType:ASTextKitTextCheckingTypeEntity
+                                                   entityAttribute:entityAttribute
+                                                             range:range];
+        minDistance = distance;
+      }
+    }
+  }];
+  return result;
+}
+
+@end