UIViewController+Insets.m

//
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#import "UIViewController+Insets.h"

@implementation UIViewController (Insets)

- (UIEdgeInsets) insetsForView:(UIView*) view
{
	UIViewController* viewController = self;
	
	//	Until root, navigation or tabBar controller
	if(![viewController isKindOfClass:[UINavigationController class]] &&
	   ![viewController isKindOfClass:[UITabBarController class]])
	{
		while(viewController.parentViewController != nil &&
			  ![viewController.parentViewController isKindOfClass:[UINavigationController class]] &&
			  ![viewController.parentViewController isKindOfClass:[UITabBarController class]])
			viewController = viewController.parentViewController;
	}
	
	const CGRect selfViewFrame = self.view.frame;
	
	const CGRect convertedFrame = [viewController.view convertRect:view.bounds fromView:view];
	
	const CGFloat topLayoutGuideLength = (([viewController respondsToSelector:@selector(topLayoutGuide)]) ? [viewController.topLayoutGuide length] : 0);
	const CGFloat bottomLayoutGuideLength = (([viewController respondsToSelector:@selector(bottomLayoutGuide)]) ? [viewController.bottomLayoutGuide length] : 0);
	
	const UIEdgeInsets rawInsets = UIEdgeInsetsMake(topLayoutGuideLength - CGRectGetMinY(convertedFrame), 0, bottomLayoutGuideLength, 0);
	
	return UIEdgeInsetsMake(MAX(0, rawInsets.top) + ABS(MIN(0, CGRectGetMinY(selfViewFrame) + CGRectGetMinY(convertedFrame))),
							MAX(0, rawInsets.left),
							MAX(0, rawInsets.bottom) - ((bottomLayoutGuideLength <= 0) ? 0 : MIN(bottomLayoutGuideLength, selfViewFrame.size.height - CGRectGetMaxY(convertedFrame))),
							MAX(0, rawInsets.right));
}

@end