rs-matter-stack 0.2.0

use core::fmt::Debug;
use core::future::Future;
use core::net::{Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV6};

use edge_nal::{UdpBind, UdpSplit};

use rs_matter::crypto::Crypto;
use rs_matter::error::{Error, ErrorCode};
use rs_matter::transport::network::mdns::builtin::BuiltinMdns;
use rs_matter::Matter;

use crate::udp;

/// A trait for running an mDNS responder.
pub trait Mdns {
    /// Run the mDNS responder with the given UDP binding, MAC address, IPv4 and IPv6 addresses, and interface index.
    ///
    /// NOTE: This trait might change once `rs-matter` starts supporting mDNS resolvers
    ///
    /// # Arguments
    /// - `matter`: A reference to the `Matter` instance.
    /// - `crypto`: An object implementing the `Crypto` trait for cryptographic operations.
    /// - `udp`: An object implementing the `UdpBind` trait for binding UDP sockets.
    /// - `mac`: The MAC address of the host, used to generate the hostname.
    /// - `ipv4`: The IPv4 address of the host.
    /// - `ipv6`: The IPv6 address of the host.
    /// - `interface`: The interface index for the host, used for IPv6 multicast.
    #[allow(clippy::too_many_arguments)]
    async fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        crypto: C,
        udp: U,
        mac: &[u8],
        ipv4: Ipv4Addr,
        ipv6: Ipv6Addr,
        interface: u32,
    ) -> Result<(), Error>
    where
        C: Crypto,
        U: UdpBind;
}

impl<T> Mdns for &mut T
where
    T: Mdns,
{
    fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        crypto: C,
        udp: U,
        mac: &[u8],
        ipv4: Ipv4Addr,
        ipv6: Ipv6Addr,
        interface: u32,
    ) -> impl Future<Output = Result<(), Error>>
    where
        C: Crypto,
        U: UdpBind,
    {
        (*self).run(matter, crypto, udp, mac, ipv4, ipv6, interface)
    }
}

impl Mdns for BuiltinMdns {
    async fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        crypto: C,
        udp: U,
        mac: &[u8],
        ipv4: Ipv4Addr,
        ipv6: Ipv6Addr,
        interface: u32,
    ) -> Result<(), Error>
    where
        C: Crypto,
        U: UdpBind,
    {
        use core::fmt::Write as _;

        use edge_nal::{MulticastV4, MulticastV6};

        use rs_matter::transport::network::mdns::builtin::Host;
        use rs_matter::transport::network::mdns::{
            MDNS_IPV4_BROADCAST_ADDR, MDNS_IPV6_BROADCAST_ADDR, MDNS_PORT,
        };

        let mut socket = udp
            .bind(SocketAddr::V6(SocketAddrV6::new(
                Ipv6Addr::UNSPECIFIED,
                MDNS_PORT,
                0,
                0,
            )))
            .await
            .map_err(map_err)?;

        socket
            .join_v4(MDNS_IPV4_BROADCAST_ADDR, ipv4)
            .await
            .map_err(map_err)?;

        socket
            .join_v6(MDNS_IPV6_BROADCAST_ADDR, interface)
            .await
            .map_err(map_err)?;

        let (recv, send) = socket.split();

        let mut hostname = heapless::String::<16>::new();
        if mac.len() == 6 {
            write_unwrap!(
                hostname,
                "{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}",
                mac[0],
                mac[1],
                mac[2],
                mac[3],
                mac[4],
                mac[5]
            );
        } else if mac.len() == 8 {
            write_unwrap!(
                hostname,
                "{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}",
                mac[0],
                mac[1],
                mac[2],
                mac[3],
                mac[4],
                mac[5],
                mac[6],
                mac[7]
            );
        } else {
            panic!("Invalid MAC address length: should be 6 or 8 bytes");
        }

        BuiltinMdns::run(
            self,
            udp::Udp(send),
            udp::Udp(recv),
            &Host {
                hostname: &hostname,
                ip: ipv4,
                ipv6,
            },
            Some(ipv4),
            Some(interface),
            matter,
            crypto,
        )
        .await
    }
}

#[cfg(feature = "zbus")]
impl Mdns for rs_matter::transport::network::mdns::avahi::AvahiMdns {
    fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        _crypto: C,
        _udp: U,
        _mac: &[u8],
        _ipv4: Ipv4Addr,
        _ipv6: Ipv6Addr,
        _interface: u32,
    ) -> impl Future<Output = Result<(), Error>>
    where
        C: Crypto,
        U: UdpBind,
    {
        Self::run(self, matter)
    }
}

#[cfg(feature = "zbus")]
impl Mdns for rs_matter::transport::network::mdns::resolve::ResolveMdns {
    fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        _crypto: C,
        _udp: U,
        _mac: &[u8],
        _ipv4: Ipv4Addr,
        _ipv6: Ipv6Addr,
        _interface: u32,
    ) -> impl Future<Output = Result<(), Error>>
    where
        C: Crypto,
        U: UdpBind,
    {
        Self::run(self, matter)
    }
}

#[cfg(feature = "zeroconf")]
impl Mdns for rs_matter::transport::network::mdns::zeroconf::ZeroconfMdns {
    fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        _crypto: C,
        _udp: U,
        _mac: &[u8],
        _ipv4: Ipv4Addr,
        _ipv6: Ipv6Addr,
        _interface: u32,
    ) -> impl Future<Output = Result<(), Error>>
    where
        C: Crypto,
        U: UdpBind,
    {
        Self::run(self, matter)
    }
}

/// An mDNS responder for Matter using the `astro-dnssd` crate.
#[cfg(feature = "astro-dnssd")]
impl Mdns for rs_matter::transport::network::mdns::astro::AstroMdns {
    async fn run<C, U>(
        &mut self,
        matter: &Matter<'_>,
        _crypto: C,
        _udp: U,
        _mac: &[u8],
        _ipv4: Ipv4Addr,
        _ipv6: Ipv6Addr,
        _interface: u32,
    ) -> Result<(), Error>
    where
        C: Crypto,
        U: UdpBind,
    {
        Self::run(self, matter).await
    }
}

// TODO: Need to fix edge-mdns's `Service` signature.
// /// Utilities for using `edge-mdns` as an mDNS responder for `rs-matter`.
// ///
// /// `rs-matter` does have a built-in mDNS imlementation, and that implementation is
// /// in fact primarily maintained by the same author who maintains `edge-mdns`.
// ///
// /// However, the key difference between the two is that the `rs-matter` built-in mDNS
// /// implementation - _for now_ -_only_ responds to queries which concern the Matter
// /// protocol itself and also does not expose a query interface. This makes it unsuitable
// /// for use in cases where the same host that operates an `rs-matter` stack needs to -
// /// for whatever reasons - to host additional service types different than the ones
// /// concerning Matter, and/or issue ad-hoc mDNS queries outside the queries necessary
// /// for operating the Matter stack.
// ///
// /// Using `edge-mdns` solves this problem by providing a general-purpose mDNS which can be
// /// shared between the `rs-matter` stack and other - user-specific use cases.
// #[cfg(feature = "edge-mdns")]
// pub mod edge_mdns {
//     use rs_matter::error::Error;
//     use rs_matter::Matter;

//     /// An adaptor from `rs-matter` buffers to `edge-mdns` buffers.
//     pub struct MatterBuffer<B>(B);

//     impl<B> MatterBuffer<B> {
//         /// Create a new instance of `MatterBuffer`
//         pub const fn new(buffer: B) -> Self {
//             Self(buffer)
//         }
//     }

//     impl<B, T> edge_mdns::buf::BufferAccess<T> for MatterBuffer<B>
//     where
//         B: rs_matter::utils::storage::pooled::BufferAccess<T>,
//         T: ?Sized,
//     {
//         type Buffer<'a>
//             = B::Buffer<'a>
//         where
//             Self: 'a;

//         async fn get(&self) -> Option<Self::Buffer<'_>> {
//             self.0.get().await
//         }
//     }

//     /// Visit all mDNS services registered by `rs-matter` as `edge_mdns::host::Service` instances.
//     pub fn emdns_services<T>(matter: &Matter<'_>, mut visitor: T) -> Result<(), Error>
//     where
//         T: FnMut(&edge_mdns::host::Service) -> Result<(), Error>,
//     {
//         matter.mdns_services(|matter_service| {
//             rs_matter::transport::network::mdns::Service::call_with(
//                 &matter_service,
//                 matter.dev_det(),
//                 matter.port(),
//                 |service| {
//                     let service = edge_mdns::host::Service {
//                         name: service.name,
//                         service: service.service,
//                         protocol: service.protocol,
//                         port: service.port,
//                         service_subtypes: service.service_subtypes,
//                         txt_kvs: service.txt_kvs,
//                         priority: 0,
//                         weight: 0,
//                     };

//                     visitor(&service)
//                 },
//             )
//         })
//     }
// }

fn map_err<E: Debug>(e: E) -> Error {
    warn!("mDNS network error: {:?}", debug2format!(e));
    ErrorCode::StdIoError.into() // TODO
}