adjust font size to make text fit within constrained size

# Conflicts:
#	AsyncDisplayKit/ASTextNode.mm

AsyncDisplayKit/TextKit/ASTextKitFontSizeAdjuster.h

@@ -1,20 +1,46 @@
-//
-//  ASTextKitFontSizeAdjuster.h
-//  AsyncDisplayKit
-//
-//  Created by Luke on 1/20/16.
-//  Copyright © 2016 Facebook. All rights reserved.
-//
+/* 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 <Foundation/Foundation.h>
+#import "ASTextKitAttributes.h"
+#import "ASTextKitContext.h"
 
 @interface ASTextKitFontSizeAdjuster : NSObject
 
 @property (nonatomic, assign) CGSize constrainedSize;
 
+/**
+ *  Creates a class that will return a scale factor the will make a string fit inside the constrained size.
+ *
+ *  "Fitting" means that both the longest word in the string will fit without breaking in the constrained
+ *  size's width AND that the entire string will try to fit within attribute's maximumLineCount. The amount
+ *  that the string will scale is based upon the attribute's pointSizeScaleFactors. If the string cannot fit
+ *  in the given width/number of lines, the smallest scale factor will be returned.
+ *
+ *  @param context                 The text kit context
+ *  @param constrainedSize         The constrained size to render into
+ *  @param textComponentAttributes The renderer's text attributes
+ */
 - (instancetype)initWithContext:(ASTextKitContext *)context
-             minimumScaleFactor:(CGFloat)minimumScaleFactor
-                constrainedSize:(CGSize)constrainedSize;
+                constrainedSize:(CGSize)constrainedSize
+              textKitAttributes:(const ASTextKitAttributes &)textComponentAttributes;
+
+/**
+ *  Returns the best fit scale factor for the text
+ */
+- (CGFloat)scaleFactor;
+
+/**
+ *  Takes all of the attributed string attributes dealing with size (font size, line spacing, kerning, etc) and
+ *  scales them by the scaleFactor. I wouldn't be surprised if I missed some in here.
+ */
++ (void)adjustFontSizeForAttributeString:(NSMutableAttributedString *)attrString withScaleFactor:(CGFloat)scaleFactor;
 
-- (void) adjustFontSize;
 @end
+
+