Adds a masked colored border to an image

ApplyBorderColorToImage

- (UIImage *)applyBorderColor:(UIColor *)color toImage:(UIImage*)toImage{
    UIGraphicsBeginImageContextWithOptions(toImage.size, NO, toImage.scale);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextTranslateCTM(context, 0, toImage.size.height);
    CGContextScaleCTM(context, 1.0, -1.0);
    
    CGContextSetBlendMode(context, kCGBlendModeNormal);
    CGRect rect = CGRectMake(0, 0, toImage.size.width, toImage.size.height);
    
    // Create gradient
    NSArray *colors = [NSArray arrayWithObjects:(id)color.CGColor, (id)color.CGColor, nil];
    CGColorSpaceRef space = CGColorSpaceCreateDeviceRGB();
    CGGradientRef gradient = CGGradientCreateWithColors(space, (__bridge CFArrayRef)colors, NULL);
    
    // Apply gradient
    CGContextClipToMask(context, rect, toImage.CGImage);
    CGContextDrawLinearGradient(context, gradient, CGPointMake(0,0), CGPointMake(0, toImage.size.height), 0);
    
    // Draw the original image
    CGFloat difference = 30.0f;
    CGSize size = [toImage size];
    CGContextTranslateCTM(context, 0, toImage.size.height);
    CGContextScaleCTM(context, 1.0, -1.0);
    CGRect smallerRect = CGRectMake(difference, difference, size.width - difference*2, size.height - difference*2);
    [toImage drawInRect:smallerRect];

    
    UIImage *coloredImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    CGGradientRelease(gradient);
    CGColorSpaceRelease(space);
    
    return coloredImage;
}