extension UIImage：为图片设置头像圆圈

import UIKit


extension UIImage {
    
    var isPortrait: Bool { return size.height > size.width }
    var isLandscape: Bool { return size.width > size.height }
    var breadth: CGFloat { return min(size.width, size.height) }
    var breadthSize: CGSize { return CGSize(width: breadth, height: breadth) }
    var breadthRect: CGRect { return CGRect(origin: .zero, size: breadthSize) }
    
    var circleMasked: UIImage? {
        
        UIGraphicsBeginImageContextWithOptions(breadthSize, false, scale)
        
        defer { UIGraphicsEndImageContext() }
        guard let cgImage = cgImage?.cropping(to: CGRect(origin: CGPoint(x: isLandscape ? floor((size.width - size.height) / 2) : 0, y: isPortrait ? floor((size.height - size.width) / 2) : 0), size: breadthSize)) else { return nil }
        
        UIBezierPath(ovalIn: breadthRect).addClip()
        UIImage(cgImage: cgImage).draw(in: breadthRect)
        return UIGraphicsGetImageFromCurrentImageContext()
    }
    
}


extension Date {
    
    func longDate() -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "dd MMM yyyy"
        return dateFormatter.string(from: self)
    }
    
    func stringDate() -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "ddMMMyyyyHHmmss"
        return dateFormatter.string(from: self)
    }
    
    func time() -> String {
        let dateFormatter = DateFormatter()
        dateFormatter.dateFormat = "HH:mm"
        return dateFormatter.string(from: self)
    }
    
    func interval(ofComponent comp: Calendar.Component, from date: Date) -> Float {
        
        let currentCalendar = Calendar.current
        
        guard  let start = currentCalendar.ordinality(of: comp, in: .era, for: date) else { return 0 }
        guard  let end = currentCalendar.ordinality(of: comp, in: .era, for: self) else { return 0 }

        return Float(start - end)
    }

}