//! Owned variants of [`ChanTarget`] and [`CircTarget`].

use serde::{Deserialize, Serialize};
use std::fmt::{self, Display};
use std::net::SocketAddr;
use tor_llcrypto::pk;

use crate::{ChanTarget, CircTarget, HasAddrs, HasRelayIds, RelayIdRef, RelayIdType};

/// RelayIds is an owned copy of the set of known identities of a relay.
///
/// Note that an object of this type will not necessarily have every type of
/// identity: it's possible that we don't know all the identities, or that one
/// of the identity types has become optional.
#[derive(Debug, Clone, Eq, PartialEq, Hash, PartialOrd, Ord, Serialize, Deserialize)]
pub struct RelayIds {
    /// Copy of the ed25519 id from the underlying ChanTarget.
    #[serde(rename = "ed25519")]
    ed_identity: Option<pk::ed25519::Ed25519Identity>,
    /// Copy of the rsa id from the underlying ChanTarget.
    #[serde(rename = "rsa")]
    rsa_identity: Option<pk::rsa::RsaIdentity>,
}

impl HasRelayIds for RelayIds {
    fn identity(&self, key_type: RelayIdType) -> Option<crate::RelayIdRef<'_>> {
        match key_type {
            RelayIdType::Ed25519 => self.ed_identity.as_ref().map(RelayIdRef::from),
            RelayIdType::Rsa => self.rsa_identity.as_ref().map(RelayIdRef::from),
        }
    }
}

impl RelayIds {
    /// Construct a new RelayIds object with a given pair of identity keys.
    pub fn new(
        ed_identity: pk::ed25519::Ed25519Identity,
        rsa_identity: pk::rsa::RsaIdentity,
    ) -> Self {
        Self {
            ed_identity: Some(ed_identity),
            rsa_identity: Some(rsa_identity),
        }
    }

    /// Construct a new `RelayIds` object from another object that implements
    /// [`HasRelayIds`].
    ///
    /// Note that it is possible to construct an _empty_ `RelayIds` object if
    /// the input does not contain any recognized identity type.
    pub fn from_relay_ids<T: HasRelayIds + ?Sized>(other: &T) -> Self {
        Self {
            ed_identity: other
                .identity(RelayIdType::Ed25519)
                .map(|r| *r.unwrap_ed25519()),
            rsa_identity: other.identity(RelayIdType::Rsa).map(|r| *r.unwrap_rsa()),
        }
    }
}

/// OwnedChanTarget is a summary of a [`ChanTarget`] that owns all of its
/// members.
// TODO pt-client: I believe that this should also implement HasChanMethods.
#[derive(Debug, Clone)]
pub struct OwnedChanTarget {
    /// Copy of the addresses from the underlying ChanTarget.
    addrs: Vec<SocketAddr>,
    /// Identities that this relay provides.
    ids: RelayIds,
}

impl HasAddrs for OwnedChanTarget {
    fn addrs(&self) -> &[SocketAddr] {
        &self.addrs[..]
    }
}

impl HasRelayIds for OwnedChanTarget {
    fn identity(&self, key_type: RelayIdType) -> Option<RelayIdRef<'_>> {
        self.ids.identity(key_type)
    }
}

impl ChanTarget for OwnedChanTarget {}

impl OwnedChanTarget {
    /// Construct a new OwnedChanTarget from its parts.
    // TODO: Put this function behind a feature.
    pub fn new(
        addrs: Vec<SocketAddr>,
        ed_identity: pk::ed25519::Ed25519Identity,
        rsa_identity: pk::rsa::RsaIdentity,
    ) -> Self {
        Self {
            addrs,
            ids: RelayIds::new(ed_identity, rsa_identity),
        }
    }

    /// Construct a OwnedChanTarget from a given ChanTarget.
    pub fn from_chan_target<C>(target: &C) -> Self
    where
        C: ChanTarget + ?Sized,
    {
        OwnedChanTarget {
            addrs: target.addrs().to_vec(),
            ids: RelayIds::from_relay_ids(target),
        }
    }

    /// Construct a new OwnedChanTarget containing _only_ the provided `addr`.
    ///
    /// If `addr` is not an address of this `ChanTarget`, return the original OwnedChanTarget.
    pub fn restrict_addr(&self, addr: &SocketAddr) -> Result<Self, Self> {
        if self.addrs.contains(addr) {
            Ok(OwnedChanTarget {
                addrs: vec![*addr],
                ids: self.ids.clone(),
            })
        } else {
            Err(self.clone())
        }
    }
}

/// Primarily for error reporting and logging
impl Display for OwnedChanTarget {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "[")?;
        match &*self.addrs {
            [] => write!(f, "?")?,
            [a] => write!(f, "{}", a)?,
            [a, ..] => write!(f, "{}+", a)?,
        };
        for ident in self.identities() {
            write!(f, " {}", ident)?;
        }
        write!(f, "]")?;
        Ok(())
    }
}

/// OwnedCircTarget is a summary of a [`CircTarget`] that owns all its
/// members.
#[derive(Debug, Clone)]
pub struct OwnedCircTarget {
    /// The fields from this object when considered as a ChanTarget.
    chan_target: OwnedChanTarget,
    /// The ntor key to use when extending to this CircTarget
    ntor_onion_key: pk::curve25519::PublicKey,
    /// The subprotocol versions that this CircTarget supports.
    protovers: tor_protover::Protocols,
}

impl OwnedCircTarget {
    /// Construct a new OwnedCircTarget from its parts.
    // TODO: Put this function behind a feature.
    pub fn new(
        chan_target: OwnedChanTarget,
        ntor_onion_key: pk::curve25519::PublicKey,
        protovers: tor_protover::Protocols,
    ) -> OwnedCircTarget {
        OwnedCircTarget {
            chan_target,
            ntor_onion_key,
            protovers,
        }
    }

    /// Construct an OwnedCircTarget from a given CircTarget.
    pub fn from_circ_target<C>(target: &C) -> Self
    where
        C: CircTarget + ?Sized,
    {
        OwnedCircTarget {
            chan_target: OwnedChanTarget::from_chan_target(target),
            ntor_onion_key: *target.ntor_onion_key(),
            // TODO: I don't like having to clone here.  Our underlying
            // protovers parsing uses an Arc, IIRC.  Can we expose that here?
            protovers: target.protovers().clone(),
        }
    }
}

/// Primarily for error reporting and logging
impl Display for OwnedCircTarget {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        Display::fmt(&self.chan_target, f)
    }
}

impl HasAddrs for OwnedCircTarget {
    fn addrs(&self) -> &[SocketAddr] {
        self.chan_target.addrs()
    }
}

impl HasRelayIds for OwnedCircTarget {
    fn identity(&self, key_type: RelayIdType) -> Option<RelayIdRef<'_>> {
        self.chan_target.identity(key_type)
    }
}

impl ChanTarget for OwnedCircTarget {}

impl CircTarget for OwnedCircTarget {
    fn ntor_onion_key(&self) -> &pk::curve25519::PublicKey {
        &self.ntor_onion_key
    }
    fn protovers(&self) -> &tor_protover::Protocols {
        &self.protovers
    }
}

#[cfg(test)]
mod test {
    #![allow(clippy::unwrap_used)]
    use super::*;

    #[test]
    #[allow(clippy::redundant_clone)]
    fn chan_target() {
        let ti = OwnedChanTarget::new(
            vec!["127.0.0.1:11".parse().unwrap()],
            [42; 32].into(),
            [45; 20].into(),
        );

        let ti2 = OwnedChanTarget::from_chan_target(&ti);
        assert_eq!(ti.addrs(), ti2.addrs());
        assert!(ti.same_relay_ids(&ti2));

        assert_eq!(format!("{:?}", ti), format!("{:?}", ti2));
        assert_eq!(format!("{:?}", ti), format!("{:?}", ti.clone()));
    }

    #[test]
    #[allow(clippy::redundant_clone)]
    fn circ_target() {
        let ch = OwnedChanTarget::new(
            vec!["127.0.0.1:11".parse().unwrap()],
            [42; 32].into(),
            [45; 20].into(),
        );
        let ct = OwnedCircTarget::new(ch.clone(), [99; 32].into(), "FlowCtrl=7".parse().unwrap());

        assert_eq!(ct.addrs(), ch.addrs());
        assert!(ct.same_relay_ids(&ch));
        assert_eq!(ct.ntor_onion_key().as_bytes(), &[99; 32]);
        assert_eq!(&ct.protovers().to_string(), "FlowCtrl=7");
        let ct2 = OwnedCircTarget::from_circ_target(&ct);
        assert_eq!(format!("{:?}", ct), format!("{:?}", ct2));
        assert_eq!(format!("{:?}", ct), format!("{:?}", ct.clone()));
    }
}