extension Collection {
    subscript(safe index: Index) -> Element? {
        return startIndex <= index && index < endIndex ? self[index] : nil

        // The same, but more performant than this >>>
        // return indices.contains(index) ? self[index] : nil
    }
}

// Usage:
let names = ["Alice", "Bob"]
let safeName: String = names[safe: 2] ?? "Unknown"
print("Safe name: \(safeName)") // "Safe name: Unknown" No crash

extension UIColor {
    convenience init(hex: String) {
        var hexSanitized = hex.trimmingCharacters(in: .whitespacesAndNewlines)
        hexSanitized = hexSanitized.replacingOccurrences(of: "#", with: "")

        // Handle different hex string formats
        switch hexSanitized.count {
        case 6: // RRGGBB
            let r = CGFloat((rgb & 0xFF0000) >> 16) / 255
            let g = CGFloat((rgb & 0x00FF00) >> 8) / 255
            let b = CGFloat(rgb & 0x0000FF) / 255
            self.init(red: r, green: g, blue: b, alpha: 1)

        case 8: // RRGGBBAA
            let r = CGFloat((rgb & 0xFF000000) >> 24) / 255
            let g = CGFloat((rgb & 0x00FF0000) >> 16) / 255
            let b = CGFloat((rgb & 0x0000FF00) >> 8) / 255
            let a = CGFloat(rgb & 0x000000FF) / 255
            self.init(red: r, green: g, blue: b, alpha: a)

        default:
            self.init(red: 0, green: 0, blue: 0, alpha: 1)
        }
    }
}

// Usage:
let backgroundColor: UIColor = UIColor(hex: "#FF5733")

extension String {
    var isNumeric: Bool {
        return Double(self) != nil
    }
}

// Usage:
let input = "123.45"
if input.isNumeric {
    print("Valid number") // ✅
}

extension UIView {
    func round(_ radius: CGFloat? = nil) {
        self.layer.cornerRadius = radius ?? self.frame.height / 2
        self.layer.masksToBounds = true
    }
}

// Usage:
let avatar = UIImageView()
avatar.round() // Make circle

class Debouncer {
    private var workItem: DispatchWorkItem?
    private let queue: DispatchQueue

    init(queue: DispatchQueue = .main) {
        self.queue = queue
    }

    func call(delay: TimeInterval, action: @escaping () -> Void) {
        workItem?.cancel()
        workItem = DispatchWorkItem(block: action)
        if let workItem = workItem {
            queue.asyncAfter(deadline: .now() + delay, execute: workItem)
        }
    }
}

// Usage:
let debouncer = Debouncer()
debouncer.call(delay: 0.5) { // Useful for throttling user input
    print("Search input processed")
}

extension Optional where Wrapped == String {
    var orEmpty: String {
        return self ?? ""
    }
}

// Usage:
let username: String? = nil
print("Hello, \(username.orEmpty)") // "Hello, "

extension Date {
    func formatted(_ format: String = "yyyy-MM-dd HH:mm") -> String {
        let formatter = DateFormatter()
        formatter.dateFormat = format
        return formatter.string(from: self)
    }
}

// Usage:
let timestamp = Date.now().formatted("MMM d, yyyy")
print(timestamp) // "Apr 13, 2025"

extension DispatchQueue {
    static func mainAsync(_ execute: @escaping () -> Void) {
        if Thread.isMainThread {
            execute()
        } else {
            DispatchQueue.main.async { execute() }
        }
    }
}

// Usage:
DispatchQueue.mainAsync {
    self.label.text = "Updated safely on main thread"
}

extension String {
    var urlEncoded: String {
        return addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) ?? self
    }
}

// Usage:
let query = "Hello World!"
let encoded = query.urlEncoded
print(encoded) // "Hello%20World%21"

extension UIImage {
    func resized(to width: CGFloat) -> UIImage? {
        let scale = width / size.width
        let height = size.height * scale
        let newSize = CGSize(width: width, height: height)

        UIGraphicsBeginImageContextWithOptions(newSize, false, 0.0)
        draw(in: CGRect(origin: .zero, size: newSize))
        let result = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return result
    }
}

// Usage:
if let resizedImage = image.resized(to: 100) {
    imageView.image = resizedImage
}

protocol Withable {}
extension Withable {
    @discardableResult
    func with(_ configure: (Self) -> Void) -> Self {
        configure(self)
        return self
    }
}
// Make all NSObject subclasses conform to Withable
extension NSObject: Withable {}

// Usage:
let label = UILabel().with { $0.text = "Hello" }

extension UIEdgeInsets {
    init(all: CGFloat) {
        self.init(top: all, left: all, bottom: all, right: all)
    }

    init(vertical: CGFloat, horizontal: CGFloat) {
        self.init(top: vertical, left: horizontal, bottom: vertical, right: horizontal)
    }
}

// Usage:
let padding = UIEdgeInsets(all: 16)
let spacing = UIEdgeInsets(vertical: 8, horizontal: 20)

extension UIApplication {
    var topMostViewController: UIViewController? {
        guard let keyWindow = UIApplication.shared.connectedScenes
                .compactMap({ ($0 as? UIWindowScene)?.keyWindow })
                .first else { return nil }

        var topController = keyWindow.rootViewController

        while let nav = topController as? UINavigationController {
            topController = nav.visibleViewController
        }

        while let tab = topController as? UITabBarController {
            topController = tab.selectedViewController
        }

        while let presented = topController?.presentedViewController {
            topController = presented
        }
        return topController
    }
}

// Usage:
if let topVC = UIApplication.shared.topMostViewController {
    topVC.present(alert, animated: true)
}

extension UIView {
    func onTap(_ target: Any, _ selector: Selector) {
        isUserInteractionEnabled = true
        let tap = UITapGestureRecognizer(target: target, action: selector)
        addGestureRecognizer(tap)
    }
}

// Usage:
myView.onTap(self, #selector(viewTapped))
@objc func viewTapped() {
    print("View was tapped!")
}

infix operator ??=: AssignmentPrecedence

func ??=<T>(lhs: inout T?, rhs: @autoclosure () -> T?) {
    if lhs == nil {
        lhs = rhs()
    }
}

// Usage:
var name: String?
name ??= "Guest"
print(name!) // "Guest"