import Foundation

/// Monotonic time and sleeping, injectable so poll loops are testable.
public protocol IrdClock: Sendable {
    /// Monotonic elapsed time since an arbitrary origin.
    var now: Duration { get }
    func sleep(for duration: Duration) async throws
}

public struct SystemClock: IrdClock {
    private let origin = ContinuousClock.now
    public init() {}
    public var now: Duration { ContinuousClock.now - origin }
    public func sleep(for duration: Duration) async throws {
        try await Task.sleep(for: duration, clock: .continuous)
    }
}