From 69e91f0fbd3af9956dfd8b8c0df9c0563347b1ec Mon Sep 17 00:00:00 2001
From: Janic Duplessis <janicduplessis@gmail.com>
Date: Sun, 28 Jul 2019 13:16:16 -0400
Subject: [PATCH] Revert "Animated image improvements (#24822)"

This reverts commit 3b67bfab1ed8f2a4cede4e58b41a8b11c63ab484.
---
 Libraries/Image/RCTGIFImageDecoder.m | 91 ++++++++++++++++++++++++++--
 Libraries/Image/RCTImageView.m       |  4 +-
 2 files changed, 89 insertions(+), 6 deletions(-)

diff --git a/Libraries/Image/RCTGIFImageDecoder.m b/Libraries/Image/RCTGIFImageDecoder.m
index a40b42529d1619..e7270978d759d3 100644
--- a/Libraries/Image/RCTGIFImageDecoder.m
+++ b/Libraries/Image/RCTGIFImageDecoder.m
@@ -31,13 +31,96 @@ - (RCTImageLoaderCancellationBlock)decodeImageData:(NSData *)imageData
                                         resizeMode:(RCTResizeMode)resizeMode
                                  completionHandler:(RCTImageLoaderCompletionBlock)completionHandler
 {
-  RCTAnimatedImage *image = [[RCTAnimatedImage alloc] initWithData:imageData scale:scale];
-  
-  if (!image) {
+  CGImageSourceRef imageSource = CGImageSourceCreateWithData((CFDataRef)imageData, NULL);
+  if (!imageSource) {
     completionHandler(nil, nil);
     return ^{};
   }
-  
+  NSDictionary<NSString *, id> *properties = (__bridge_transfer NSDictionary *)CGImageSourceCopyProperties(imageSource, NULL);
+  CGFloat loopCount = 0;
+  if ([[properties[(id)kCGImagePropertyGIFDictionary] allKeys] containsObject:(id)kCGImagePropertyGIFLoopCount]) {
+    loopCount = [properties[(id)kCGImagePropertyGIFDictionary][(id)kCGImagePropertyGIFLoopCount] unsignedIntegerValue];
+    if (loopCount == 0) {
+      // A loop count of 0 means infinite
+      loopCount = HUGE_VALF;
+    } else {
+      // A loop count of 1 means it should repeat twice, 2 means, thrice, etc.
+      loopCount += 1;
+    }
+  }
+
+  UIImage *image = nil;
+  size_t imageCount = CGImageSourceGetCount(imageSource);
+  if (imageCount > 1) {
+
+    NSTimeInterval duration = 0;
+    NSMutableArray<NSNumber *> *delays = [NSMutableArray arrayWithCapacity:imageCount];
+    NSMutableArray<id /* CGIMageRef */> *images = [NSMutableArray arrayWithCapacity:imageCount];
+    for (size_t i = 0; i < imageCount; i++) {
+
+      CGImageRef imageRef = CGImageSourceCreateImageAtIndex(imageSource, i, NULL);
+      if (!imageRef) {
+        continue;
+      }
+      if (!image) {
+        image = [UIImage imageWithCGImage:imageRef scale:scale orientation:UIImageOrientationUp];
+      }
+
+      NSDictionary<NSString *, id> *frameProperties = (__bridge_transfer NSDictionary *)CGImageSourceCopyPropertiesAtIndex(imageSource, i, NULL);
+      NSDictionary<NSString *, id> *frameGIFProperties = frameProperties[(id)kCGImagePropertyGIFDictionary];
+
+      const NSTimeInterval kDelayTimeIntervalDefault = 0.1;
+      NSNumber *delayTime = frameGIFProperties[(id)kCGImagePropertyGIFUnclampedDelayTime] ?: frameGIFProperties[(id)kCGImagePropertyGIFDelayTime];
+      if (delayTime == nil) {
+        if (delays.count == 0) {
+          delayTime = @(kDelayTimeIntervalDefault);
+        } else {
+          delayTime = delays.lastObject;
+        }
+      }
+
+      const NSTimeInterval kDelayTimeIntervalMinimum = 0.02;
+      if (delayTime.floatValue < (float)kDelayTimeIntervalMinimum - FLT_EPSILON) {
+        delayTime = @(kDelayTimeIntervalDefault);
+      }
+
+      duration += delayTime.doubleValue;
+      [delays addObject:delayTime];
+      [images addObject:(__bridge_transfer id)imageRef];
+    }
+    CFRelease(imageSource);
+
+    NSMutableArray<NSNumber *> *keyTimes = [NSMutableArray arrayWithCapacity:delays.count];
+    NSTimeInterval runningDuration = 0;
+    for (NSNumber *delayNumber in delays) {
+      [keyTimes addObject:@(runningDuration / duration)];
+      runningDuration += delayNumber.doubleValue;
+    }
+
+    [keyTimes addObject:@1.0];
+
+    // Create animation
+    CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:@"contents"];
+    animation.calculationMode = kCAAnimationDiscrete;
+    animation.repeatCount = loopCount;
+    animation.keyTimes = keyTimes;
+    animation.values = images;
+    animation.duration = duration;
+    animation.removedOnCompletion = NO;
+    animation.fillMode = kCAFillModeForwards;
+    image.reactKeyframeAnimation = animation;
+
+  } else {
+
+    // Don't bother creating an animation
+    CGImageRef imageRef = CGImageSourceCreateImageAtIndex(imageSource, 0, NULL);
+    if (imageRef) {
+      image = [UIImage imageWithCGImage:imageRef scale:scale orientation:UIImageOrientationUp];
+      CFRelease(imageRef);
+    }
+    CFRelease(imageSource);
+  }
+
   completionHandler(nil, image);
   return ^{};
 }
diff --git a/Libraries/Image/RCTImageView.m b/Libraries/Image/RCTImageView.m
index c193cbd3e51567..93521e65f8a913 100644
--- a/Libraries/Image/RCTImageView.m
+++ b/Libraries/Image/RCTImageView.m
@@ -82,7 +82,7 @@ @implementation RCTImageView
   // Whether the latest change of props requires the image to be reloaded
   BOOL _needsReload;
 
-   RCTUIImageViewAnimated *_imageView;
+   UIImageView *_imageView;
 }
 
 - (instancetype)initWithBridge:(RCTBridge *)bridge
@@ -98,7 +98,7 @@ - (instancetype)initWithBridge:(RCTBridge *)bridge
                selector:@selector(clearImageIfDetached)
                    name:UIApplicationDidEnterBackgroundNotification
                  object:nil];
-    _imageView = [[RCTUIImageViewAnimated alloc] init];
+    _imageView = [[UIImageView alloc] init];
     _imageView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
     [self addSubview:_imageView];
   }