refactor: ios optimalization

Author: hejsztynx

ios/inputAttributesManager/InputAttributesManager.mm

@@ -66,20 +66,27 @@ - (void)clearRemovedTypingAttributes {
 }
 
 - (void)handleDirtyRangesStyling {
-  // snapshot edited ranges (including 0-length ones) before filtering, so
-  // we can use them when recalculating adjacent ordered lists
-  NSArray<NSValue *> *editedRangesForListRecalc = [_dirtyRanges copy];
-
-  // Filter out 0 length ranges for styling.
-  NSPredicate *predicate = [NSPredicate
-      predicateWithBlock:^BOOL(NSValue *evaluatedObject, NSDictionary *_) {
-        return [evaluatedObject rangeValue].length > 0;
-      }];
-  [_dirtyRanges filterUsingPredicate:predicate];
+  OrderedListStyle *orderedListStyle =
+      (OrderedListStyle *)_input->stylesDict[@([OrderedListStyle getType])];
 
   for (NSValue *rangeObj in _dirtyRanges) {
     NSRange dirtyRange = [rangeObj rangeValue];
 
+    // deletion (0-length dirtyRange) means we need to refresh the ordered
+    // list margins. If the ordered list style is not present itself,
+    // it might mean that we have just deleted a list element and need
+    // to recalculate the potentially split list (current adjacent lists)
+    if (dirtyRange.length == 0) {
+      if (orderedListStyle != nil) {
+        if ([orderedListStyle detect:dirtyRange]) {
+          [orderedListStyle applyStyling:dirtyRange];
+        } else {
+          [orderedListStyle recalculateListsAroundEditedRange:dirtyRange];
+        }
+      }
+      continue;
+    }
+
     // dirty range can sometimes be wrong because of apple doing some changes
     // behind the scenes
     if (dirtyRange.location + dirtyRange.length >
@@ -94,6 +101,13 @@ - (void)handleDirtyRangesStyling {
       presentStyles[@([[style class] getType])] = [style all:dirtyRange];
     }
 
+    // it's possible that ordered list style has just got removed,
+    // so we have to refresh adjacent ordered lists
+    if (orderedListStyle != nil &&
+        [presentStyles[@([OrderedListStyle getType])] count] == 0) {
+      [orderedListStyle recalculateListsAroundEditedRange:dirtyRange];
+    }
+
     // now reset the attributes to default ones
     [_input->textView.textStorage setAttributes:_input->defaultTypingAttributes
                                           range:dirtyRange];
@@ -126,15 +140,6 @@ - (void)handleDirtyRangesStyling {
       }
     }
   }
-  // refresh ordered lists adjacent to any edit
-  OrderedListStyle *orderedListStyle =
-      (OrderedListStyle *)_input->stylesDict[@([OrderedListStyle getType])];
-  if (orderedListStyle != nil) {
-    for (NSValue *rangeObj in editedRangesForListRecalc) {
-      [orderedListStyle
-          recalculateListsAroundEditedRange:[rangeObj rangeValue]];
-    }
-  }
 
   // do the typing attributes management, with no selection
   [self manageTypingAttributesWithOnlySelection:NO];

ios/styles/OrderedListStyle.mm

@@ -182,48 +182,78 @@ - (NSRange)contiguousOrderedListRangeContaining:(NSRange)range
     return NSMakeRange(range.location, 0);
   }
 
+  NSTextStorage *textStorage = self.host.textView.textStorage;
+  NSRange fullRange = NSMakeRange(0, length);
   NSUInteger seedLocation = MIN(range.location, length - 1);
-  NSRange initialParagraph =
-      [fullText paragraphRangeForRange:NSMakeRange(seedLocation, 0)];
-  NSRange firstParagraph = initialParagraph;
 
-  NSInteger precedingCount = 0;
+  NSRange seedRun;
+  [textStorage attribute:NSParagraphStyleAttributeName
+                    atIndex:seedLocation
+      longestEffectiveRange:&seedRun
+                    inRange:fullRange];
 
-  // seek backward over preceding ordered-list paragraphs, counting items
-  while (firstParagraph.location > 0) {
-    NSRange previous = [fullText
-        paragraphRangeForRange:NSMakeRange(firstParagraph.location - 1, 0)];
-    if (![self detect:NSMakeRange(previous.location, 0)]) {
+  NSUInteger firstParagraphStart = seedRun.location;
+  NSUInteger lastParagraphEnd = NSMaxRange(seedRun);
+
+  // seek backward over preceding ordered-list runs
+  while (firstParagraphStart > 0) {
+    if (![self detect:NSMakeRange(firstParagraphStart - 1, 0)]) {
       break;
     }
-    firstParagraph = previous;
-    precedingCount += 1;
+    NSRange previousRun;
+    [textStorage attribute:NSParagraphStyleAttributeName
+                      atIndex:firstParagraphStart - 1
+        longestEffectiveRange:&previousRun
+                      inRange:fullRange];
+    firstParagraphStart = previousRun.location;
   }
 
-  // seek forward over following ordered-list paragraphs, counting items
-  NSInteger followingCount = 0;
-  NSRange lastParagraph = initialParagraph;
-  NSRange cursor = initialParagraph;
-  while (true) {
-    lastParagraph = cursor;
-    NSUInteger nextLocation = NSMaxRange(cursor);
-    if (nextLocation >= length) {
-      break;
-    }
-    NSRange next =
-        [fullText paragraphRangeForRange:NSMakeRange(nextLocation, 0)];
-    if (![self detect:NSMakeRange(next.location, 0)]) {
+  // seek forward over following ordered-list runs
+  while (lastParagraphEnd < length) {
+    if (![self detect:NSMakeRange(lastParagraphEnd, 0)]) {
       break;
     }
-    cursor = next;
-    followingCount += 1;
+    NSRange nextRun;
+    [textStorage attribute:NSParagraphStyleAttributeName
+                      atIndex:lastParagraphEnd
+        longestEffectiveRange:&nextRun
+                      inRange:fullRange];
+    lastParagraphEnd = NSMaxRange(nextRun);
   }
 
+  NSRange listRange =
+      NSMakeRange(firstParagraphStart, lastParagraphEnd - firstParagraphStart);
+
   if (outCount != nullptr) {
-    *outCount = precedingCount + followingCount + 1;
+    *outCount =
+        [self countParagraphsInRange:listRange
+                              inText:self.host.textView.textStorage.string];
   }
-  return NSMakeRange(firstParagraph.location,
-                     NSMaxRange(lastParagraph) - firstParagraph.location);
+  return listRange;
+}
+
+// counts paragraphs (newline-delimited) within a range that is already known
+// to start and end exactly on paragraph boundaries
+- (NSInteger)countParagraphsInRange:(NSRange)listRange inText:(NSString *)text {
+  if (listRange.length == 0) {
+    return 0;
+  }
+
+  NSCharacterSet *newlineSet = [NSCharacterSet newlineCharacterSet];
+  NSUInteger rangeEnd = NSMaxRange(listRange);
+  NSUInteger cursor = listRange.location;
+  NSInteger count = 0;
+
+  while (cursor < rangeEnd) {
+    count += 1;
+    NSRange newline =
+        [text rangeOfCharacterFromSet:newlineSet
+                              options:0
+                                range:NSMakeRange(cursor, rangeEnd - cursor)];
+    cursor = newline.location != NSNotFound ? NSMaxRange(newline) : rangeEnd;
+  }
+
+  return count;
 }
 
 @end