//===----------------------------------------------------------------------===//
// Copyright © 2025-2026 Apple Inc. and the Containerization project authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//   https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//===----------------------------------------------------------------------===//

import ContainerizationExtras

/// A network interface.
public protocol Interface: Sendable {
    /// The interface IPv4 address and subnet prefix length, as a CIDR address.
    /// Example: `192.168.64.3/24`
    var ipv4Address: CIDRv4 { get }

    /// The IPv4 gateway address for the default route, or nil for no IPv4 default route.
    var ipv4Gateway: IPv4Address? { get }

    /// The interface IPv6 address and subnet prefix length, as a CIDRv6 address, or nil for no IPv6 address.
    /// Example: `fd00::1/64`
    var ipv6Address: CIDRv6? { get }

    /// The IPv6 gateway address for the default route, or nil for no IPv6 default route.
    var ipv6Gateway: IPv6Address? { get }

    /// The interface MAC address, or nil to auto-configure the address.
    var macAddress: MACAddress? { get }

    /// The interface MTU (Maximum Transmission Unit).
    var mtu: UInt32 { get }
}

extension Interface {
    public var mtu: UInt32 { 1500 }
    public var ipv6Address: CIDRv6? { nil }
    public var ipv6Gateway: IPv6Address? { nil }
}