SDWebImageSwiftUI/SDWebImageSwiftUI/Classes/ObjC/SDAnimatedImageInterface.m

/*
* This file is part of the SDWebImage package.
* (c) DreamPiggy <lizhuoli1126@126.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/

#import "SDAnimatedImageInterface.h"
#if SD_WATCH

#pragma mark - SPI

@protocol CALayerProtocol <NSObject>
@property (nullable, strong) id contents;
@property CGFloat contentsScale;
@end

@protocol UIViewProtocol <NSObject>
@property (nonatomic, strong, readonly) id<CALayerProtocol> layer;
@property (nonatomic, assign) SDImageScaleMode contentMode;
@property (nonatomic, readonly) id<UIViewProtocol> superview;
@property (nonatomic, readonly, copy) NSArray<id<UIViewProtocol>> *subviews;
@property (nonatomic, readonly) id window;
@property (nonatomic) CGFloat alpha;
@property (nonatomic, getter=isHidden) BOOL hidden;
@property (nonatomic, getter=isOpaque) BOOL opaque;
@property (nonatomic) CGRect frame;
@property (nonatomic) CGRect bounds;
@property (nonatomic) CGPoint center;
@property (nonatomic, readonly) CGSize intrinsicContentSize;
@property(nonatomic) NSInteger tag;

- (void)invalidateIntrinsicContentSize;
- (void)layoutSubviews;
- (CGSize)sizeThatFits:(CGSize)size;
- (void)sizeToFit;

@end

@protocol UIImageViewProtocol <UIViewProtocol>

@property (nullable, nonatomic, strong) UIImage *image;
- (void)startAnimating;
- (void)stopAnimating;
@property (nonatomic, readonly, getter=isAnimating) BOOL animating;

@end

@interface WKInterfaceObject ()

// This is needed for dynamic created WKInterfaceObject, like `WKInterfaceMap`
- (instancetype)_initForDynamicCreationWithInterfaceProperty:(NSString *)property;
- (NSDictionary *)interfaceDescriptionForDynamicCreation;
// This is remote UIView
@property (nonatomic, strong, readwrite) id<UIViewProtocol> _interfaceView;

@end

@interface SDAnimatedImageInterface ()

@property (nonatomic, strong, readwrite) UIImage *currentFrame;
@property (nonatomic, assign, readwrite) NSUInteger currentFrameIndex;
@property (nonatomic, assign, readwrite) NSUInteger currentLoopCount;
@property (nonatomic, assign, getter=isAnimating, readwrite) BOOL animating;
@property (nonatomic, assign) BOOL shouldAnimate;
@property (nonatomic, strong) SDAnimatedImagePlayer *player; // The animation player.
@property (nonatomic) id<CALayerProtocol> imageViewLayer; // The actual rendering layer.

@end

@implementation SDAnimatedImageInterface

- (instancetype)init {
    Class cls = [self class];
    NSString *UUID = [NSUUID UUID].UUIDString;
    NSString *property = [NSString stringWithFormat:@"%@_%@", cls, UUID];
    self = [self _initForDynamicCreationWithInterfaceProperty:property];
    if (self) {
        self.runLoopMode = NSRunLoopCommonModes;
        self.playbackRate = 1.0;
    }
    return self;
}

- (NSDictionary *)interfaceDescriptionForDynamicCreation {
    // This is called by WatchKit
    return @{
        @"type" : @"image",
        @"property" : self.interfaceProperty,
    };
}

- (void)setImage:(UIImage *)image {
    if (_image == image) {
        return;
    }
    _image = image;
    
    // Stop animating
    self.player = nil;
    self.currentFrame = nil;
    self.currentFrameIndex = 0;
    self.currentLoopCount = 0;
    
    ((id<UIImageViewProtocol>)[self _interfaceView]).image = image;
    if ([image.class conformsToProtocol:@protocol(SDAnimatedImage)]) {
        // Create animted player
        self.player = [SDAnimatedImagePlayer playerWithProvider:(id<SDAnimatedImage>)image];
        
        if (!self.player) {
            // animated player nil means the image format is not supported, or frame count <= 1
            return;
        }
        
        // Custom Loop Count
        if (self.animationRepeatCount != nil) {
            self.player.totalLoopCount = self.animationRepeatCount.unsignedIntegerValue;
        }
        
        // RunLoop Mode
        self.player.runLoopMode = self.runLoopMode;

        // Play Rate
        self.player.playbackRate = self.playbackRate;
        
        // Setup handler
        __weak typeof(self) wself = self;
        self.player.animationFrameHandler = ^(NSUInteger index, UIImage * frame) {
            __strong typeof(self) sself = wself;
            sself.currentFrameIndex = index;
            sself.currentFrame = frame;
            [sself displayLayer:sself.imageViewLayer];
        };
        self.player.animationLoopHandler = ^(NSUInteger loopCount) {
            __strong typeof(self) sself = wself;
            sself.currentLoopCount = loopCount;
        };
        
        // Start animating
        [self startAnimating];
        
        [self displayLayer:self.imageViewLayer];
    }
}

- (void)updateAnimation {
    [self updateShouldAnimate];
    if (self.shouldAnimate && self.isAnimating) {
        [self startAnimating];
    } else {
        [self stopAnimating];
    }
}

- (void)displayLayer:(id<CALayerProtocol>)layer {
    UIImage *currentFrame = self.currentFrame;
    if (currentFrame) {
        layer.contentsScale = currentFrame.scale;
        layer.contents = (__bridge id)currentFrame.CGImage;
    }
}

// on watchOS, it's the native imageView itself's layer
- (id<CALayerProtocol>)imageViewLayer {
    return [self _interfaceView].layer;
}

- (void)updateShouldAnimate
{
    id<UIViewProtocol> view = [self _interfaceView];
    BOOL isVisible = view.window && view.superview && ![view isHidden] && view.alpha > 0.0;
    self.shouldAnimate = self.player && isVisible;
}

- (void)startAnimating {
    self.animating = YES;
    if (self.player) {
        [self updateShouldAnimate];
        if (self.shouldAnimate) {
            [self.player startPlaying];
        }
    } else if (_image.images.count > 0) {
        [super startAnimating];
    }
}

- (void)stopAnimating {
    self.animating = NO;
    if (self.player) {
        if (self.resetFrameIndexWhenStopped) {
            [self.player stopPlaying];
        } else {
            [self.player pausePlaying];
        }
        if (self.clearBufferWhenStopped) {
            [self.player clearFrameBuffer];
        }
    } else if (_image.images.count > 0) {
        [super stopAnimating];
    }
}

- (void)setContentMode:(SDImageScaleMode)contentMode {
    [self _interfaceView].contentMode = contentMode;
}

- (SDImageScaleMode)contentMode {
    return [self _interfaceView].contentMode;
}

@end

#endif