Update the behavior about `SDAnimatedImage` for the category metadata

Now `SDAnimatedImage` can be static image, so some check is not correct

SDWebImage/Core/SDAnimatedImage.m

@@ -335,7 +335,7 @@ static CGFloat SDImageScaleFromPath(NSString *string) {
 @implementation SDAnimatedImage (Metadata)
 
 - (BOOL)sd_isAnimated {
-    return YES;
+    return self.animatedImageFrameCount > 1;
 }
 
 - (NSUInteger)sd_imageLoopCount {
@@ -347,11 +347,21 @@ static CGFloat SDImageScaleFromPath(NSString *string) {
 }
 
 - (NSUInteger)sd_imageFrameCount {
-    return self.animatedImageFrameCount;
+    NSUInteger frameCount = self.animatedImageFrameCount;
+    if (frameCount > 1) {
+        return frameCount;
+    } else {
+        return 1;
+    }
 }
 
 - (SDImageFormat)sd_imageFormat {
-    return self.animatedImageFormat;
+    NSData *animatedImageData = self.animatedImageData;
+    if (animatedImageData) {
+        return [NSData sd_imageFormatForImageData:animatedImageData];
+    } else {
+        return [super sd_imageFormat];
+    }
 }
 
 - (void)setSd_imageFormat:(SDImageFormat)sd_imageFormat {

SDWebImage/Core/SDWebImageDefine.m

@@ -83,11 +83,8 @@ inline UIImage * _Nullable SDScaledImageForScaleFactor(CGFloat scale, UIImage *
                 scaledImage = [[image.class alloc] initWithData:data scale:scale];
             }
         }
-        if (scaledImage) {
-            return scaledImage;
-        }
     }
-    if (image.sd_isAnimated) {
+    if (!scaledImage && image.sd_isAnimated) {
         UIImage *animatedImage;
 #if SD_UIKIT || SD_WATCH
         // `UIAnimatedImage` images share the same size and scale.
@@ -100,7 +97,6 @@ inline UIImage * _Nullable SDScaledImageForScaleFactor(CGFloat scale, UIImage *
         }
         
         animatedImage = [UIImage animatedImageWithImages:scaledImages duration:image.duration];
-        animatedImage.sd_imageLoopCount = image.sd_imageLoopCount;
 #else
         // Animated GIF for `NSImage` need to grab `NSBitmapImageRep`;
         NSRect imageRect = NSMakeRect(0, 0, image.size.width, image.size.height);

SDWebImage/Core/UIImage+Metadata.h

@@ -24,6 +24,8 @@
  * NSImage currently only support animated via `NSBitmapImageRep`(GIF) or `SDAnimatedImageRep`(APNG/GIF/WebP) unlike UIImage.
  * The getter of this property will get the loop count from animated imageRep
  * The setter of this property will set the loop count from animated imageRep
+ * SDAnimatedImage:
+ * Returns `animatedImageLoopCount`
  */
 @property (nonatomic, assign) NSUInteger sd_imageLoopCount;
 
@@ -35,6 +37,8 @@
  * AppKit:
  * Returns the underlaying `NSBitmapImageRep` or `SDAnimatedImageRep` frame count.
  * Returns 1 for static image.
+ * SDAnimatedImage:
+ * Returns `animatedImageFrameCount`
  */
 @property (nonatomic, assign, readonly) NSUInteger sd_imageFrameCount;
 
@@ -42,7 +46,9 @@
  * UIKit:
  * Check the `images` array property.
  * AppKit:
- * NSImage currently only support animated via GIF imageRep unlike UIImage. It will check the imageRep's frame count.
+ * NSImage currently only support animated via GIF imageRep unlike UIImage. It will check the imageRep's frame count > 1.
+ * SDAnimatedImage:
+ * Check `animatedImageFrameCount` > 1
  */
 @property (nonatomic, assign, readonly) BOOL sd_isAnimated;
 
@@ -51,6 +57,8 @@
  * Check the `isSymbolImage` property. Also check the system PDF(iOS 11+) && SVG(iOS 13+) support.
  * AppKit:
  * NSImage supports PDF && SVG && EPS imageRep, check the imageRep class.
+ * SDAnimatedImage:
+ * Returns `NO`
  */
 @property (nonatomic, assign, readonly) BOOL sd_isVector;
 
@@ -58,6 +66,7 @@
  * The image format represent the original compressed image data format.
  * If you don't manually specify a format, this information is retrieve from CGImage using `CGImageGetUTType`, which may return nil for non-CG based image. At this time it will return `SDImageFormatUndefined` as default value.
  * @note Note that because of the limitations of categories this property can get out of sync if you create another instance with CGImage or other methods.
+ * @note For `SDAnimatedImage`, returns `animatedImageFormat` when animated, or fallback when static.
  */
 @property (nonatomic, assign) SDImageFormat sd_imageFormat;