func debounce<T>(delay: TimeInterval, function: @escaping (T) -> Void, complete: @escaping () -> Void = { }) -> (T) -> Void {
    let queue = DispatchQueue(label: "Debouncer")
    var current: DispatchWorkItem?

    return { input in
        current?.cancel()
        let new = DispatchWorkItem {
            function(input)
            complete()
        }
        current = new
        queue.asyncAfter(deadline: .now() + delay, execute: new)
    }
}