@MainActor
public final class PackageOperationQueue {
    private var pending: [() async -> Void] = []
    private var isRunning = false

    public init() {}

    public func enqueue(_ operation: @escaping @MainActor () async throws -> Void) async throws {
        try await withCheckedThrowingContinuation { continuation in
            pending.append {
                do {
                    try await operation()
                    continuation.resume()
                } catch {
                    continuation.resume(throwing: error)
                }
            }

            if !isRunning {
                Task { [self] in
                    await runNext()
                }
            }
        }
    }

    private func runNext() async {
        guard !pending.isEmpty else {
            isRunning = false
            return
        }

        isRunning = true
        let op = pending.removeFirst()
        await op()
        await runNext()
    }
}