UIImage+QMUI.m

/**
 * Tencent is pleased to support the open source community by making QMUI_iOS available.
 * Copyright (C) 2016-2021 THL A29 Limited, a Tencent company. All rights reserved.
 * Licensed under the MIT License (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
 * http://opensource.org/licenses/MIT
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
 */

//
//  UIImage+QMUI.m
//  qmui
//
//  Created by QMUI Team on 15/7/20.
//

#import "UIImage+QMUI.h"
#import "QMUICore.h"
#import "UIBezierPath+QMUI.h"
#import "UIColor+QMUI.h"
#import "QMUILog.h"
#import "NSArray+QMUI.h"
#import "CALayer+QMUI.h"
#import <ImageIO/ImageIO.h>
#import <CoreImage/CoreImage.h>
#import <Accelerate/Accelerate.h>

CG_INLINE CGSize
CGSizeFlatSpecificScale(CGSize size, float scale) {
    return CGSizeMake(flatSpecificScale(size.width, scale), flatSpecificScale(size.height, scale));
}

@implementation UIImage (QMUI)

+ (void)load {
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        
        ExtendImplementationOfNonVoidMethodWithoutArguments([UIImage class], @selector(description), NSString *, ^NSString *(UIImage *selfObject, NSString *originReturnValue) {
            return ([NSString stringWithFormat:@"%@, scale = %@", originReturnValue, @(selfObject.scale)]);
        });
        
        OverrideImplementation([UIImage class], @selector(resizableImageWithCapInsets:resizingMode:), ^id(__unsafe_unretained Class originClass, SEL originCMD, IMP (^originalIMPProvider)(void)) {
            return ^UIImage *(UIImage *selfObject, UIEdgeInsets capInsets, UIImageResizingMode resizingMode) {
                
                if (!CGSizeIsEmpty(selfObject.size) && (UIEdgeInsetsGetHorizontalValue(capInsets) >= selfObject.size.width || UIEdgeInsetsGetVerticalValue(capInsets) >= selfObject.size.height)) {
                    // 如果命中这个判断，请减小 capInsets 的值
                    QMUILogWarn(@"UIImage (QMUI)", @"UIImage (QMUI) resizableImageWithCapInsets 传进来的 capInsets 的水平/垂直方向的和应该小于图片本身的大小，否则会导致 render 时出现 invalid context 0x0 的错误。");
                }
                
                // call super
                UIImage *(*originSelectorIMP)(id, SEL, UIEdgeInsets, UIImageResizingMode);
                originSelectorIMP = (UIImage *(*)(id, SEL, UIEdgeInsets, UIImageResizingMode))originalIMPProvider();
                UIImage *result = originSelectorIMP(selfObject, originCMD, capInsets, resizingMode);
                
                return result;
            };
        });
        
        OverrideImplementation([UIImage class], @selector(imageWithRenderingMode:), ^id(__unsafe_unretained Class originClass, SEL originCMD, IMP (^originalIMPProvider)(void)) {
            return ^UIImage *(UIImage *selfObject, UIImageRenderingMode mode) {
                
                // call super
                UIImage * (*originSelectorIMP)(id, SEL, UIImageRenderingMode);
                originSelectorIMP = (UIImage * (*)(id, SEL, UIImageRenderingMode))originalIMPProvider();
                UIImage * result = originSelectorIMP(selfObject, originCMD, mode);
                
                NSString *name = selfObject.qmui_name;
                if (![result.qmui_name isEqualToString:name]) {
                    [result qmui_bindObject:name forKey:kQMUIImageNameKey];
                }
                return result;
            };
        });
    });
}

+ (UIImage *)qmui_imageWithSize:(CGSize)size opaque:(BOOL)opaque scale:(CGFloat)scale actions:(void (^)(CGContextRef contextRef))actionBlock {
    if (!actionBlock || CGSizeIsEmpty(size)) {
        return nil;
    }
    UIGraphicsImageRendererFormat *format = [[UIGraphicsImageRendererFormat alloc] init];
    format.scale = scale;
    format.opaque = opaque;
    UIGraphicsImageRenderer *render = [[UIGraphicsImageRenderer alloc] initWithSize:size format:format];
    UIImage *imageOut = [render imageWithActions:^(UIGraphicsImageRendererContext * _Nonnull rendererContext) {
        CGContextRef context = rendererContext.CGContext;
        CGContextInspectContextReturnVoid(context);
        actionBlock(context);
    }];
    return imageOut;
}

static NSString * const kQMUIImageNameKey = @"kQMUIImageNameKey";
- (NSString *)qmui_name {
    NSString *name = [self qmui_getBoundObjectForKey:kQMUIImageNameKey];
    if (name.length) {
        return name;
    }
    UIImageAsset *asset = [self valueForKey:@"_imageAsset"];// UIImage.imageAsset 是懒加载的，如果当前 image 并非从 Asset 里获取的，直接访问 getter 也会导致它构造一个 UIImageAsset 对象出来，导致后续的 assetName 为随机字符串，所以这里通过 valueForKey: 的方式直接访问 Ivar
    SEL selector = NSSelectorFromString(@"assetName");
    if ([asset respondsToSelector:selector]) {
        BeginIgnorePerformSelectorLeaksWarning
        name = [asset performSelector:selector];
        EndIgnorePerformSelectorLeaksWarning
        if (name.length) {
            return name;
        }
    }
    return nil;
}

- (BOOL)qmui_resizable {
    BOOL result;
    [self qmui_performSelector:NSSelectorFromString(@"_isResizable") withPrimitiveReturnValue:&result];
    return result;
}

- (CGSize)qmui_sizeInPixel {
    CGSize size = CGSizeMake(self.size.width * self.scale, self.size.height * self.scale);
    return size;
}

- (BOOL)qmui_opaque {
    CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(self.CGImage);
    BOOL opaque = alphaInfo == kCGImageAlphaNoneSkipLast
    || alphaInfo == kCGImageAlphaNoneSkipFirst
    || alphaInfo == kCGImageAlphaNone;
    return opaque;
}

- (UIColor *)qmui_averageColor {
	unsigned char rgba[4] = {};
	CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
	CGContextRef context = CGBitmapContextCreate(rgba, 1, 1, 8, 4, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
	CGContextInspectContext(context, nil);
	CGContextDrawImage(context, CGRectMake(0, 0, 1, 1), self.CGImage);
	CGColorSpaceRelease(colorSpace);
	CGContextRelease(context);
	if(rgba[3] > 0) {
		return [UIColor colorWithRed:((CGFloat)rgba[0] / rgba[3])
			                   green:((CGFloat)rgba[1] / rgba[3])
			                    blue:((CGFloat)rgba[2] / rgba[3])
			                   alpha:((CGFloat)rgba[3] / 255.0)];
	} else {
		return [UIColor colorWithRed:((CGFloat)rgba[0]) / 255.0
                               green:((CGFloat)rgba[1]) / 255.0
								blue:((CGFloat)rgba[2]) / 255.0
							   alpha:((CGFloat)rgba[3]) / 255.0];
	}
}

- (UIImage *)qmui_grayImage {
    // CGBitmapContextCreate 是无倍数的，所以要自己换算成1倍
    CGSize size = self.qmui_sizeInPixel;
    CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();
    CGContextRef context = CGBitmapContextCreate(NULL, size.width, size.height, 8, 0, colorSpace, kCGBitmapByteOrderDefault);
    CGContextInspectContext(context, nil);
    CGColorSpaceRelease(colorSpace);
    if (context == NULL) {
        return nil;
    }
    CGRect imageRect = CGRectMakeWithSize(size);
    CGContextDrawImage(context, imageRect, self.CGImage);
    
    UIImage *grayImage = nil;
    CGImageRef imageRef = CGBitmapContextCreateImage(context);
    if (self.qmui_opaque) {
        grayImage = [UIImage imageWithCGImage:imageRef scale:self.scale orientation:self.imageOrientation];
    } else {
        CGContextRef alphaContext = CGBitmapContextCreate(NULL, size.width, size.height, 8, 0, nil, kCGImageAlphaOnly);
        CGContextDrawImage(alphaContext, imageRect, self.CGImage);
        CGImageRef mask = CGBitmapContextCreateImage(alphaContext);
		CGImageRef maskedGrayImageRef = CGImageCreateWithMask(imageRef, mask);
        grayImage = [UIImage imageWithCGImage:maskedGrayImageRef scale:self.scale orientation:self.imageOrientation];
        CGImageRelease(mask);
		CGImageRelease(maskedGrayImageRef);
        CGContextRelease(alphaContext);
        
        // 用 CGBitmapContextCreateImage 方式创建出来的图片，CGImageAlphaInfo 总是为 CGImageAlphaInfoNone，导致 qmui_opaque 与原图不一致，所以这里再做多一步
        grayImage = [UIImage qmui_imageWithSize:grayImage.size opaque:NO scale:grayImage.scale actions:^(CGContextRef contextRef) {
            [grayImage drawInRect:CGRectMakeWithSize(grayImage.size)];
        }];
    }
    
    CGContextRelease(context);
    CGImageRelease(imageRef);
    return grayImage;
}

- (UIImage *)qmui_imageWithAlpha:(CGFloat)alpha {
    return [UIImage qmui_imageWithSize:self.size opaque:NO scale:self.scale actions:^(CGContextRef contextRef) {
        [self drawInRect:CGRectMakeWithSize(self.size) blendMode:kCGBlendModeNormal alpha:alpha];
    }];
}

- (UIImage *)qmui_imageWithTintColor:(UIColor *)tintColor {
    // iOS 13 的 imageWithTintColor: 方法里并不会去更新 CGImage，所以通过它更改了图片颜色后再获取到的 CGImage 依然是旧的，因此暂不使用
//    if (@available(iOS 13.0, *)) {
//        return [self imageWithTintColor:tintColor];
//    }
    BOOL opaque = self.qmui_opaque ? tintColor.qmui_alpha >= 1.0 : NO;// 如果图片不透明但 tintColor 半透明，则生成的图片也应该是半透明的
    UIImage *result = [UIImage qmui_imageWithSize:self.size opaque:opaque scale:self.scale actions:^(CGContextRef contextRef) {
        CGContextTranslateCTM(contextRef, 0, self.size.height);
        CGContextScaleCTM(contextRef, 1.0, -1.0);
        if (!opaque) {
            CGContextSetBlendMode(contextRef, kCGBlendModeNormal);
            CGContextClipToMask(contextRef, CGRectMakeWithSize(self.size), self.CGImage);
        }
        CGContextSetFillColorWithColor(contextRef, tintColor.CGColor);
        CGContextFillRect(contextRef, CGRectMakeWithSize(self.size));
    }];
    
    SEL selector = NSSelectorFromString(@"qmui_generatorSupportsDynamicColor");
    if ([NSStringFromClass(tintColor.class) containsString:@"QMUIThemeColor"] && [UIImage respondsToSelector:selector]) {
        BOOL supports;
        [UIImage.class qmui_performSelector:selector withPrimitiveReturnValue:&supports];
        QMUIAssert(supports, @"UIImage (QMUI)", @"UIImage (QMUITheme) hook 尚未生效，QMUIThemeColor 生成的图片无法自动转成 QMUIThemeImage，可能导致 theme 切换时无法刷新。");
    }
    return result;
}

- (UIImage *)qmui_imageWithBlendColor:(UIColor *)blendColor {
    UIImage *coloredImage = [self qmui_imageWithTintColor:blendColor];
    CIFilter *filter = [CIFilter filterWithName:@"CIColorBlendMode"];
    [filter setValue:[CIImage imageWithCGImage:self.CGImage] forKey:kCIInputBackgroundImageKey];
    [filter setValue:[CIImage imageWithCGImage:coloredImage.CGImage] forKey:kCIInputImageKey];
    CIImage *outputImage = filter.outputImage;
    CIContext *context = [CIContext contextWithOptions:nil];
    CGImageRef imageRef = [context createCGImage:outputImage fromRect:outputImage.extent];
    UIImage *resultImage = [UIImage imageWithCGImage:imageRef scale:self.scale orientation:self.imageOrientation];
    CGImageRelease(imageRef);
    return resultImage;
}

- (UIImage *)qmui_imageWithImageAbove:(UIImage *)image atPoint:(CGPoint)point {
    return [UIImage qmui_imageWithSize:self.size opaque:self.qmui_opaque scale:self.scale actions:^(CGContextRef contextRef) {
        [self drawInRect:CGRectMakeWithSize(self.size)];
        [image drawAtPoint:point];
    }];
}

- (UIImage *)qmui_imageWithSpacingExtensionInsets:(UIEdgeInsets)extension {
    CGSize contextSize = CGSizeMake(self.size.width + UIEdgeInsetsGetHorizontalValue(extension), self.size.height + UIEdgeInsetsGetVerticalValue(extension));
    return [UIImage qmui_imageWithSize:contextSize opaque:self.qmui_opaque scale:self.scale actions:^(CGContextRef contextRef) {
        [self drawAtPoint:CGPointMake(extension.left, extension.top)];
    }];
}

- (UIImage *)qmui_imageWithClippedRect:(CGRect)rect {
    CGContextInspectSize(rect.size);
    CGRect imageRect = CGRectMakeWithSize(self.size);
    if (CGRectContainsRect(rect, imageRect)) {
        // 要裁剪的区域比自身大，所以不用裁剪直接返回自身即可
        return self;
    }
    // 由于CGImage是以pixel为单位来计算的，而UIImage是以point为单位，所以这里需要将传进来的point转换为pixel
    CGRect scaledRect = CGRectApplyScale(rect, self.scale);
    CGImageRef imageRef = CGImageCreateWithImageInRect(self.CGImage, scaledRect);
    UIImage *imageOut = [UIImage imageWithCGImage:imageRef scale:self.scale orientation:self.imageOrientation];
    CGImageRelease(imageRef);
    return imageOut;
}

- (UIImage *)qmui_imageWithClippedCornerRadius:(CGFloat)cornerRadius {
    return [self qmui_imageWithClippedCornerRadius:cornerRadius scale:self.scale];
}

- (UIImage *)qmui_imageWithClippedCornerRadius:(CGFloat)cornerRadius scale:(CGFloat)scale {
    if (cornerRadius <= 0) {
        return self;
    }
    return [UIImage qmui_imageWithSize:self.size opaque:NO scale:scale actions:^(CGContextRef contextRef) {
        [[UIBezierPath bezierPathWithRoundedRect:CGRectMakeWithSize(self.size) cornerRadius:cornerRadius] addClip];
        [self drawInRect:CGRectMakeWithSize(self.size)];
    }];
}

- (UIImage *)qmui_imageResizedInLimitedSize:(CGSize)size {
    return [self qmui_imageResizedInLimitedSize:size resizingMode:QMUIImageResizingModeScaleAspectFit];
}

- (UIImage *)qmui_imageResizedInLimitedSize:(CGSize)size resizingMode:(QMUIImageResizingMode)resizingMode {
    return [self qmui_imageResizedInLimitedSize:size resizingMode:resizingMode scale:self.scale];
}

- (UIImage *)qmui_imageResizedInLimitedSize:(CGSize)size resizingMode:(QMUIImageResizingMode)resizingMode scale:(CGFloat)scale {
    size = CGSizeFlatSpecificScale(size, scale);
    CGSize imageSize = self.size;
    CGRect drawingRect = CGRectZero;// 图片绘制的 rect
    CGSize contextSize = CGSizeZero;// 画布的大小
    
    if (CGSizeEqualToSize(size, imageSize) && scale == self.scale) {
        return self;
    }
    
    if (resizingMode >= QMUIImageResizingModeScaleAspectFit && resizingMode <= QMUIImageResizingModeScaleAspectFillBottom) {
        CGFloat horizontalRatio = size.width / imageSize.width;
        CGFloat verticalRatio = size.height / imageSize.height;
        CGFloat ratio = 0;
        if (resizingMode >= QMUIImageResizingModeScaleAspectFill && resizingMode < (QMUIImageResizingModeScaleAspectFill + 10)) {
            ratio = MAX(horizontalRatio, verticalRatio);
        } else {
            // 默认按 QMUIImageResizingModeScaleAspectFit
            ratio = MIN(horizontalRatio, verticalRatio);
        }
        CGSize resizedSize = CGSizeMake(flatSpecificScale(imageSize.width * ratio, scale), flatSpecificScale(imageSize.height * ratio, scale));
        contextSize = CGSizeMake(MIN(size.width, resizedSize.width), MIN(size.height, resizedSize.height));
        drawingRect.origin.x = CGFloatGetCenter(contextSize.width, resizedSize.width);
        
        CGFloat originY = 0;
        if (resizingMode % 10 == 1) {
            // toTop
            originY = 0;
        } else if (resizingMode % 10 == 2) {
            // toBottom
            originY = contextSize.height - resizedSize.height;
        } else {
            // default is Center
            originY = CGFloatGetCenter(contextSize.height, resizedSize.height);
        }
        drawingRect.origin.y = originY;
        
        drawingRect.size = resizedSize;
    } else {
        // 默认按照 QMUIImageResizingModeScaleToFill
        drawingRect = CGRectMakeWithSize(size);
        contextSize = size;
    }
    
    return [UIImage qmui_imageWithSize:contextSize opaque:self.qmui_opaque scale:scale actions:^(CGContextRef contextRef) {
        [self drawInRect:drawingRect];
    }];
}

- (UIImage *)qmui_imageWithOrientation:(UIImageOrientation)orientation {
    if (orientation == UIImageOrientationUp) {
        return self;
    }
    
    CGSize contextSize = self.size;
    if (orientation == UIImageOrientationLeft || orientation == UIImageOrientationRight) {
        contextSize = CGSizeMake(contextSize.height, contextSize.width);
    }
    
    contextSize = CGSizeFlatSpecificScale(contextSize, self.scale);
    
    return [UIImage qmui_imageWithSize:contextSize opaque:NO scale:self.scale actions:^(CGContextRef contextRef) {
        // 画布的原点在左上角，旋转后可能图片就飞到画布外了，所以旋转前先把图片摆到特定位置再旋转，图片刚好就落在画布里
        switch (orientation) {
            case UIImageOrientationUp:
                // 上
                break;
            case UIImageOrientationDown:
                // 下
                CGContextTranslateCTM(contextRef, contextSize.width, contextSize.height);
                CGContextRotateCTM(contextRef, AngleWithDegrees(180));
                break;
            case UIImageOrientationLeft:
                // 左
                CGContextTranslateCTM(contextRef, 0, contextSize.height);
                CGContextRotateCTM(contextRef, AngleWithDegrees(-90));
                break;
            case UIImageOrientationRight:
                // 右
                CGContextTranslateCTM(contextRef, contextSize.width, 0);
                CGContextRotateCTM(contextRef, AngleWithDegrees(90));
                break;
            case UIImageOrientationUpMirrored:
            case UIImageOrientationDownMirrored:
                // 向上、向下翻转是一样的
                CGContextTranslateCTM(contextRef, 0, contextSize.height);
                CGContextScaleCTM(contextRef, 1, -1);
                break;
            case UIImageOrientationLeftMirrored:
            case UIImageOrientationRightMirrored:
                // 向左、向右翻转是一样的
                CGContextTranslateCTM(contextRef, contextSize.width, 0);
                CGContextScaleCTM(contextRef, -1, 1);
                break;
        }
        
        // 在前面画布的旋转、移动的结果上绘制自身即可，这里不用考虑旋转带来的宽高置换的问题
        [self drawInRect:CGRectMakeWithSize(self.size)];
    }];
}

- (UIImage *)qmui_imageWithBorderColor:(UIColor *)borderColor path:(UIBezierPath *)path {
    if (!borderColor) {
        return self;
    }
    
    return [UIImage qmui_imageWithSize:self.size opaque:self.qmui_opaque scale:self.scale actions:^(CGContextRef contextRef) {
        [self drawInRect:CGRectMakeWithSize(self.size)];
        CGContextSetStrokeColorWithColor(contextRef, borderColor.CGColor);
        [path stroke];
    }];
}

- (UIImage *)qmui_imageWithBorderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth cornerRadius:(CGFloat)cornerRadius {
    return [self qmui_imageWithBorderColor:borderColor borderWidth:borderWidth cornerRadius:cornerRadius dashedLengths:0];
}

- (UIImage *)qmui_imageWithBorderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth cornerRadius:(CGFloat)cornerRadius dashedLengths:(const CGFloat *)dashedLengths {
    if (!borderColor || !borderWidth) {
        return self;
    }
    
    UIBezierPath *path;
    CGRect rect = CGRectInset(CGRectMake(0, 0, self.size.width, self.size.height), borderWidth / 2, borderWidth / 2);// 调整rect，从而保证绘制描边时像素对齐
    if (cornerRadius > 0) {
        path = [UIBezierPath bezierPathWithRoundedRect:rect cornerRadius:cornerRadius];
    } else {
        path = [UIBezierPath bezierPathWithRect:rect];
    }
    
    path.lineWidth = borderWidth;
    if (dashedLengths) {
        [path setLineDash:dashedLengths count:2 phase:0];
    }
    return [self qmui_imageWithBorderColor:borderColor path:path];
}

- (UIImage *)qmui_imageWithBorderColor:(UIColor *)borderColor borderWidth:(CGFloat)borderWidth borderPosition:(QMUIImageBorderPosition)borderPosition {
    if (borderPosition == QMUIImageBorderPositionAll) {
        return [self qmui_imageWithBorderColor:borderColor borderWidth:borderWidth cornerRadius:0];
    } else {
        // TODO 使用bezierPathWithRoundedRect:byRoundingCorners:cornerRadii:这个系统接口
        UIBezierPath* path = [UIBezierPath bezierPath];
        if ((QMUIImageBorderPositionBottom & borderPosition) == QMUIImageBorderPositionBottom) {
            [path moveToPoint:CGPointMake(0, self.size.height - borderWidth / 2)];
            [path addLineToPoint:CGPointMake(self.size.width, self.size.height - borderWidth / 2)];
        }
        if ((QMUIImageBorderPositionTop & borderPosition) == QMUIImageBorderPositionTop) {
            [path moveToPoint:CGPointMake(0, borderWidth / 2)];
            [path addLineToPoint:CGPointMake(self.size.width, borderWidth / 2)];
        }
        if ((QMUIImageBorderPositionLeft & borderPosition) == QMUIImageBorderPositionLeft) {
            [path moveToPoint:CGPointMake(borderWidth / 2, 0)];
            [path addLineToPoint:CGPointMake(borderWidth / 2, self.size.height)];
        }
        if ((QMUIImageBorderPositionRight & borderPosition) == QMUIImageBorderPositionRight) {
            [path moveToPoint:CGPointMake(self.size.width - borderWidth / 2, 0)];
            [path addLineToPoint:CGPointMake(self.size.width - borderWidth / 2, self.size.height)];
        }
        [path setLineWidth:borderWidth];
        [path closePath];
        return [self qmui_imageWithBorderColor:borderColor path:path];
    }
    return self;
}

- (UIImage *)qmui_imageWithMaskImage:(UIImage *)maskImage usingMaskImageMode:(BOOL)usingMaskImageMode {
    CGImageRef maskRef = [maskImage CGImage];
    CGImageRef mask;
    if (usingMaskImageMode) {
        // 用CGImageMaskCreate创建生成的 image mask。
        // 黑色部分显示，白色部分消失，透明部分显示，其他颜色会按照颜色的灰色度对图片做透明处理。
        mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
                                 CGImageGetHeight(maskRef),
                                 CGImageGetBitsPerComponent(maskRef),
                                 CGImageGetBitsPerPixel(maskRef),
                                 CGImageGetBytesPerRow(maskRef),
                                 CGImageGetDataProvider(maskRef), nil, YES);
    } else {
        // 用一个纯CGImage作为mask。这个image必须是单色(例如：黑白色、灰色)、没有alpha通道、不能被其他图片mask。系统的文档：If `mask' is an image, then it must be in a monochrome color space (e.g. DeviceGray, GenericGray, etc...), may not have alpha, and may not itself be masked by an image mask or a masking color.
        // 白色部分显示，黑色部分消失，透明部分消失，其他灰色度对图片做透明处理。
         mask = maskRef;
    }
    CGImageRef maskedImage = CGImageCreateWithMask(self.CGImage, mask);
    UIImage *returnImage = [UIImage imageWithCGImage:maskedImage scale:self.scale orientation:self.imageOrientation];
    if (usingMaskImageMode) {
        CGImageRelease(mask);
    }
    CGImageRelease(maskedImage);
    return returnImage;
}

+ (UIImage *)qmui_animatedImageWithData:(NSData *)data {
    return [self qmui_animatedImageWithData:data scale:1];
}

+ (UIImage *)qmui_animatedImageWithData:(NSData *)data scale:(CGFloat)scale {
    // http://www.jianshu.com/p/767af9c690a3
    // https://github.com/rs/SDWebImage
    if (!data) {
        return nil;
    }
    CGImageSourceRef source = CGImageSourceCreateWithData((__bridge CFDataRef)data, NULL);
    size_t count = CGImageSourceGetCount(source);
    UIImage *animatedImage = nil;
    scale = scale == 0 ? ScreenScale : scale;
    if (count <= 1) {
        animatedImage = [[UIImage alloc] initWithData:data scale:scale];
    } else {
        NSMutableArray<UIImage *> *images = [[NSMutableArray alloc] init];
        NSTimeInterval duration = 0.0f;
        for (size_t i = 0; i < count; i++) {
            CGImageRef image = CGImageSourceCreateImageAtIndex(source, i, NULL);
            duration += [self qmui_frameDurationAtIndex:i source:source];
            UIImage *frameImage = [UIImage imageWithCGImage:image scale:scale orientation:UIImageOrientationUp];
            [images addObject:frameImage];
            CGImageRelease(image);
        }
        if (!duration) {
            duration = (1.0f / 10.0f) * count;
        }
        animatedImage = [UIImage animatedImageWithImages:images duration:duration];
    }
    CFRelease(source);
    return animatedImage;
}

+ (float)qmui_frameDurationAtIndex:(NSUInteger)index source:(CGImageSourceRef)source {
    float frameDuration = 0.1f;
    CFDictionaryRef cfFrameProperties = CGImageSourceCopyPropertiesAtIndex(source, index, nil);
    NSDictionary<NSString *, NSDictionary *> *frameProperties = (__bridge NSDictionary *)cfFrameProperties;
    NSDictionary<NSString *, NSNumber *> *gifProperties = frameProperties[(NSString *)kCGImagePropertyGIFDictionary];
    NSNumber *delayTimeUnclampedProp = gifProperties[(NSString *)kCGImagePropertyGIFUnclampedDelayTime];
    if (delayTimeUnclampedProp) {
        frameDuration = [delayTimeUnclampedProp floatValue];
    } else {
        NSNumber *delayTimeProp = gifProperties[(NSString *)kCGImagePropertyGIFDelayTime];
        if (delayTimeProp) {
            frameDuration = [delayTimeProp floatValue];
        }
    }
    CFRelease(cfFrameProperties);
    return frameDuration;
}

+ (UIImage *)qmui_animatedImageNamed:(NSString *)name {
    return [UIImage qmui_animatedImageNamed:name scale:1];
}

+ (UIImage *)qmui_animatedImageNamed:(NSString *)name scale:(CGFloat)scale {
    NSString *type = name.pathExtension.lowercaseString;
    type = type.length > 0 ? type : @"gif";
    NSString *path = [[NSBundle mainBundle] pathForResource:name.stringByDeletingPathExtension ofType:type];
    NSData *data = [NSData dataWithContentsOfFile:path];
    return [UIImage qmui_animatedImageWithData:data scale:scale];
}

+ (UIImage *)qmui_imageWithStrokeColor:(UIColor *)strokeColor size:(CGSize)size path:(UIBezierPath *)path addClip:(BOOL)addClip {
    size = CGSizeFlatted(size);
    return [UIImage qmui_imageWithSize:size opaque:NO scale:0 actions:^(CGContextRef contextRef) {
        CGContextSetStrokeColorWithColor(contextRef, strokeColor.CGColor);
        if (addClip) [path addClip];
        [path stroke];
    }];
}

+ (UIImage *)qmui_imageWithStrokeColor:(UIColor *)strokeColor size:(CGSize)size lineWidth:(CGFloat)lineWidth cornerRadius:(CGFloat)cornerRadius {
    CGContextInspectSize(size);
    // 往里面缩一半的lineWidth，应为stroke绘制线的时候是往两边绘制的
    // 如果cornerRadius为0的时候使用bezierPathWithRoundedRect:cornerRadius:会有问题，左上角老是会多出一点，所以区分开
    UIBezierPath *path;
    CGRect rect = CGRectInset(CGRectMakeWithSize(size), lineWidth / 2, lineWidth / 2);
    if (cornerRadius > 0) {
        path = [UIBezierPath bezierPathWithRoundedRect:rect cornerRadius:cornerRadius];
    } else {
        path = [UIBezierPath bezierPathWithRect:rect];
    }
    [path setLineWidth:lineWidth];
    return [UIImage qmui_imageWithStrokeColor:strokeColor size:size path:path addClip:NO];
}

+ (UIImage *)qmui_imageWithStrokeColor:(UIColor *)strokeColor size:(CGSize)size lineWidth:(CGFloat)lineWidth borderPosition:(QMUIImageBorderPosition)borderPosition {
    CGContextInspectSize(size);
    if (borderPosition == QMUIImageBorderPositionAll) {
        return [UIImage qmui_imageWithStrokeColor:strokeColor size:size lineWidth:lineWidth cornerRadius:0];
    } else {
        // TODO 使用bezierPathWithRoundedRect:byRoundingCorners:cornerRadii:这个系统接口
        UIBezierPath* path = [UIBezierPath bezierPath];
        if ((QMUIImageBorderPositionBottom & borderPosition) == QMUIImageBorderPositionBottom) {
            [path moveToPoint:CGPointMake(0, size.height - lineWidth / 2)];
            [path addLineToPoint:CGPointMake(size.width, size.height - lineWidth / 2)];
        }
        if ((QMUIImageBorderPositionTop & borderPosition) == QMUIImageBorderPositionTop) {
            [path moveToPoint:CGPointMake(0, lineWidth / 2)];
            [path addLineToPoint:CGPointMake(size.width, lineWidth / 2)];
        }
        if ((QMUIImageBorderPositionLeft & borderPosition) == QMUIImageBorderPositionLeft) {
            [path moveToPoint:CGPointMake(lineWidth / 2, 0)];
            [path addLineToPoint:CGPointMake(lineWidth / 2, size.height)];
        }
        if ((QMUIImageBorderPositionRight & borderPosition) == QMUIImageBorderPositionRight) {
            [path moveToPoint:CGPointMake(size.width - lineWidth / 2, 0)];
            [path addLineToPoint:CGPointMake(size.width - lineWidth / 2, size.height)];
        }
        [path setLineWidth:lineWidth];
        [path closePath];
        return [UIImage qmui_imageWithStrokeColor:strokeColor size:size path:path addClip:NO];
    }
}

+ (UIImage *)qmui_imageWithColor:(UIColor *)color {
    return [UIImage qmui_imageWithColor:color size:CGSizeMake(4, 4) cornerRadius:0];
}

+ (UIImage *)qmui_imageWithColor:(UIColor *)color size:(CGSize)size cornerRadius:(CGFloat)cornerRadius {
    size = CGSizeFlatted(size);
    CGContextInspectSize(size);
    
    color = color ? color : UIColorClear;
	BOOL opaque = (cornerRadius == 0.0 && [color qmui_alpha] == 1.0);
    UIImage *result = [UIImage qmui_imageWithSize:size opaque:opaque scale:0 actions:^(CGContextRef contextRef) {
        CGContextSetFillColorWithColor(contextRef, color.CGColor);
        
        if (cornerRadius > 0) {
            UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:CGRectMakeWithSize(size) cornerRadius:cornerRadius];
            [path addClip];
            [path fill];
        } else {
            CGContextFillRect(contextRef, CGRectMakeWithSize(size));
        }
    }];
    SEL selector = NSSelectorFromString(@"qmui_generatorSupportsDynamicColor");
    if ([NSStringFromClass(color.class) containsString:@"QMUIThemeColor"] && [UIImage respondsToSelector:selector]) {
        BOOL supports;
        [UIImage.class qmui_performSelector:selector withPrimitiveReturnValue:&supports];
        QMUIAssert(supports, @"UIImage (QMUI)", @"UIImage (QMUITheme) hook 尚未生效，QMUIThemeColor 生成的图片无法自动转成 QMUIThemeImage，可能导致 theme 切换时无法刷新。");
    }
    return result;
}

+ (UIImage *)qmui_imageWithColor:(UIColor *)color size:(CGSize)size cornerRadiusArray:(NSArray<NSNumber *> *)cornerRadius {
    size = CGSizeFlatted(size);
    CGContextInspectSize(size);
    color = color ? color : [UIColor colorWithRed:1 green:1 blue:1 alpha:1];
    return [UIImage qmui_imageWithSize:size opaque:NO scale:0 actions:^(CGContextRef contextRef) {
        
        CGContextSetFillColorWithColor(contextRef, color.CGColor);
        
        UIBezierPath *path = [UIBezierPath qmui_bezierPathWithRoundedRect:CGRectMakeWithSize(size) cornerRadiusArray:cornerRadius lineWidth:0];
        [path addClip];
        [path fill];
    }];
}

+ (UIImage *)qmui_imageWithGradientColors:(NSArray<UIColor *> *)colors type:(QMUIImageGradientType)type locations:(NSArray<NSNumber *> *)locations size:(CGSize)size cornerRadiusArray:(NSArray<NSNumber *> *)cornerRadius {
    size = CGSizeFlatted(size);
    CGContextInspectSize(size);
    locations = locations ?: @[@0, @1];
    QMUIAssert(type != QMUIImageGradientTypeRadial || (type == QMUIImageGradientTypeRadial && locations.count == 2), @"UIImage (QMUI)", @"QMUIImageGradientTypeRadial 只能与2个 location 搭配使用，目前 locations 为 %@ 个", @(locations.count));
    return [UIImage qmui_imageWithSize:size opaque:NO scale:0 actions:^(CGContextRef  _Nonnull contextRef) {
        if (cornerRadius) {
            UIBezierPath *path = [UIBezierPath qmui_bezierPathWithRoundedRect:CGRectMakeWithSize(size) cornerRadiusArray:cornerRadius lineWidth:0];
            [path addClip];
        }
        
        // 这里不用 CAGradientLayer 来渲染，因为发现实际效果会产生一些色差，暂不清楚为什么，所以只能用 Core Graphic 渲染
        CGColorSpaceRef spaceRef = CGColorSpaceCreateDeviceRGB();
        CGFloat cLocations[locations.count];
        for (NSInteger i = 0; i < locations.count; i++) {
            cLocations[i] = locations[i].qmui_CGFloatValue;
        }

        CGGradientRef gradient = CGGradientCreateWithColors(spaceRef, (CFArrayRef)[colors qmui_mapWithBlock:^id _Nonnull(UIColor * _Nonnull item, NSInteger index) {
            return (id)item.CGColor;
        }], cLocations);
        if (type == QMUIImageGradientTypeRadial) {
            CGFloat minSize = MIN(size.width, size.height);
            CGFloat radius = minSize / 2;
            CGFloat horizontalRatio = size.width / minSize;
            CGFloat verticalRatio = size.height / minSize;
            // 缩放是为了让渐变的圆形可以按照 size 变成椭圆的
            CGContextTranslateCTM(contextRef, -(horizontalRatio - 1) * size.width / 2, -(verticalRatio - 1) * size.height / 2);
            CGContextScaleCTM(contextRef, horizontalRatio, verticalRatio);
            CGContextDrawRadialGradient(contextRef,
                                        gradient,
                                        CGPointMake(size.width / 2, size.height / 2),
                                        0,
                                        CGPointMake(size.width / 2, size.height / 2),
                                        radius,
                                        kCGGradientDrawsBeforeStartLocation);
        } else {
            CGPoint startPoint = CGPointZero;
            CGPoint endPoint = CGPointZero;
            if (type == QMUIImageGradientTypeHorizontal) {
                startPoint = CGPointMake(0, 0);
                endPoint = CGPointMake(size.width, 0);
            } else if(type == QMUIImageGradientTypeVertical) {
                startPoint = CGPointMake(0, 0);
                endPoint = CGPointMake(0, size.height);
            }else if (type == QMUIImageGradientTypeTopLeftToBottomRight){
                startPoint = CGPointMake(0, 0);
                endPoint = CGPointMake(size.width, size.height);
            }else if (type == QMUIImageGradientTypeTopRightToBottomLeft){
                startPoint = CGPointMake(size.width, 0);
                endPoint = CGPointMake(0, size.height);
            }
            CGContextDrawLinearGradient(contextRef, gradient, startPoint, endPoint, kCGGradientDrawsBeforeStartLocation);
        }
        CGColorSpaceRelease(spaceRef);
        CGGradientRelease(gradient);
    }];
}

+ (UIImage *)qmui_imageWithShape:(QMUIImageShape)shape size:(CGSize)size lineWidth:(CGFloat)lineWidth tintColor:(UIColor *)tintColor {
    size = CGSizeFlatted(size);
    CGContextInspectSize(size);
    
    tintColor = tintColor ? : [UIColor colorWithRed:1 green:1 blue:1 alpha:1];
    
    return [UIImage qmui_imageWithSize:size opaque:NO scale:0 actions:^(CGContextRef contextRef) {
        UIBezierPath *path = nil;
        BOOL drawByStroke = NO;
        CGFloat drawOffset = lineWidth / 2;
        switch (shape) {
            case QMUIImageShapeOval: {
                path = [UIBezierPath bezierPathWithOvalInRect:CGRectMakeWithSize(size)];
            }
                break;
            case QMUIImageShapeTriangle: {
                path = [UIBezierPath bezierPath];
                [path moveToPoint:CGPointMake(0, size.height)];
                [path addLineToPoint:CGPointMake(size.width / 2, 0)];
                [path addLineToPoint:CGPointMake(size.width, size.height)];
                [path closePath];
            }
                break;
            case QMUIImageShapeNavBack: {
                drawByStroke = YES;
                path = [UIBezierPath bezierPath];
                path.lineWidth = lineWidth;
                [path moveToPoint:CGPointMake(size.width - drawOffset, drawOffset)];
                [path addLineToPoint:CGPointMake(0 + drawOffset, size.height / 2.0)];
                [path addLineToPoint:CGPointMake(size.width - drawOffset, size.height - drawOffset)];
            }
                break;
            case QMUIImageShapeDisclosureIndicator: {
                drawByStroke = YES;
                path = [UIBezierPath bezierPath];
                path.lineWidth = lineWidth;
                [path moveToPoint:CGPointMake(drawOffset, drawOffset)];
                [path addLineToPoint:CGPointMake(size.width - drawOffset, size.height / 2)];
                [path addLineToPoint:CGPointMake(drawOffset, size.height - drawOffset)];
            }
                break;
            case QMUIImageShapeCheckmark: {
                CGFloat lineAngle = M_PI_4;
                path = [UIBezierPath bezierPath];
                [path moveToPoint:CGPointMake(0, size.height / 2)];
                [path addLineToPoint:CGPointMake(size.width / 3, size.height)];
                [path addLineToPoint:CGPointMake(size.width, lineWidth * sin(lineAngle))];
                [path addLineToPoint:CGPointMake(size.width - lineWidth * cos(lineAngle), 0)];
                [path addLineToPoint:CGPointMake(size.width / 3, size.height - lineWidth / sin(lineAngle))];
                [path addLineToPoint:CGPointMake(lineWidth * sin(lineAngle), size.height / 2 - lineWidth * sin(lineAngle))];
                [path closePath];
            }
                break;
            case QMUIImageShapeDetailButtonImage: {
                drawByStroke = YES;
                path = [UIBezierPath bezierPathWithOvalInRect:CGRectInset(CGRectMakeWithSize(size), drawOffset, drawOffset)];
                path.lineWidth = lineWidth;
            }
                break;
            case QMUIImageShapeNavClose: {
                drawByStroke = YES;
                path = [UIBezierPath bezierPath];
                [path moveToPoint:CGPointMake(0, 0)];
                [path addLineToPoint:CGPointMake(size.width, size.height)];
                [path closePath];
                [path moveToPoint:CGPointMake(size.width, 0)];
                [path addLineToPoint:CGPointMake(0, size.height)];
                [path closePath];
                path.lineWidth = lineWidth;
                path.lineCapStyle = kCGLineCapRound;
            }
                break;
            default:
                break;
        }
        
        if (drawByStroke) {
            CGContextSetStrokeColorWithColor(contextRef, tintColor.CGColor);
            [path stroke];
        } else {
            CGContextSetFillColorWithColor(contextRef, tintColor.CGColor);
            [path fill];
        }
        
        if (shape == QMUIImageShapeDetailButtonImage) {
            CGFloat fontPointSize = flat(size.height * 0.8);
            UIFont *font = [UIFont fontWithName:@"Georgia" size:fontPointSize];
            NSAttributedString *string = [[NSAttributedString alloc] initWithString:@"i" attributes:@{NSFontAttributeName: font, NSForegroundColorAttributeName: tintColor}];
            CGSize stringSize = [string boundingRectWithSize:size options:NSStringDrawingUsesFontLeading context:nil].size;
            [string drawAtPoint:CGPointMake(CGFloatGetCenter(size.width, stringSize.width), CGFloatGetCenter(size.height, stringSize.height))];
        }
    }];
}

+ (UIImage *)qmui_imageWithShape:(QMUIImageShape)shape size:(CGSize)size tintColor:(UIColor *)tintColor {
    CGFloat lineWidth = 0;
    switch (shape) {
        case QMUIImageShapeNavBack:
            lineWidth = 2.0f;
            break;
        case QMUIImageShapeDisclosureIndicator:
            lineWidth = 1.5f;
            break;
        case QMUIImageShapeCheckmark:
            lineWidth = 1.5f;
            break;
        case QMUIImageShapeDetailButtonImage:
            lineWidth = 1.0f;
            break;
        case QMUIImageShapeNavClose:
            lineWidth = 1.2f;   // 取消icon默认的lineWidth
            break;
        default:
            break;
    }
    return [UIImage qmui_imageWithShape:shape size:size lineWidth:lineWidth tintColor:tintColor];
}

+ (UIImage *)qmui_imageWithView:(UIView *)view {
    CGContextInspectSize(view.bounds.size);
    return [UIImage qmui_imageWithSize:view.bounds.size opaque:NO scale:0 actions:^(CGContextRef contextRef) {
        [view.layer renderInContext:contextRef];
    }];
}

+ (UIImage *)qmui_imageWithView:(UIView *)view afterScreenUpdates:(BOOL)afterUpdates {
    // iOS 7 截图新方式，性能好会好一点，不过不一定适用，因为这个方法的使用条件是：界面要已经render完，否则截到得图将会是empty。
    CGContextInspectSize(view.bounds.size);
    return [UIImage qmui_imageWithSize:view.bounds.size opaque:NO scale:0 actions:^(CGContextRef contextRef) {
        [view drawViewHierarchyInRect:CGRectMakeWithSize(view.bounds.size) afterScreenUpdates:afterUpdates];
    }];
}

@end