slancha-wire 0.17.0

//! Multi-endpoint routing for v0.5.17 (dual-slot sessions).
//!
//! Each wire session can hold up to TWO slots:
//!   - **Federation** — on a public relay (default `https://wireup.net`),
//!     listed in the phonebook, reachable across machines.
//!   - **Local** — on a loopback relay (default `http://127.0.0.1:8771`,
//!     started with `wire relay-server --local-only`), invisible from
//!     off-box, sub-millisecond round-trip for same-machine sister-Claude
//!     traffic.
//!
//! Both slots are advertised to paired peers via the `pair_drop` body's
//! `endpoints[]` array (additive — v0.5.16-and-earlier peers see only
//! the federation endpoint at the top-level legacy fields, unchanged).
//!
//! Routing decision lives in `cmd_push`: walk a peer's pinned endpoints
//! in priority order (local first if we also have a local slot), POST
//! the event, fall back to the next endpoint on failure. Pulling: the
//! daemon reads from BOTH slots, dedupes by `event_id`.
//!
//! Storage shape in `relay_state.json`:
//!
//! ```jsonc
//! {
//!   "self": {
//!     // Self-slot still carries the flat triple (the #263 daemon-survival
//!     // fix synthesizes a sister's flat fields; self-collapse is Part A /
//!     // a separate slice — see RFC-006).
//!     "relay_url": "https://wireup.net",
//!     "slot_id":   "abc...",
//!     "slot_token":"...",
//!     "endpoints": [
//!       {"relay_url": "https://wireup.net",     "slot_id": "abc...",  "slot_token": "...", "scope": "federation"},
//!       {"relay_url": "http://127.0.0.1:8771",  "slot_id": "loop...", "slot_token": "...", "scope": "local"}
//!     ]
//!   },
//!   "peers": {
//!     "wire-mesh": {
//!       // RFC-006 Part B (#268): peers carry `endpoints[]` ONLY — the single
//!       // peer-routing source. The flat relay_url/slot_id/slot_token triple
//!       // is no longer written (it was the "stale flat beats fresh array"
//!       // routing hazard). All peer-pin readers resolve through
//!       // `peer_endpoints_in_priority_order` / `peer_primary_endpoint`.
//!       "endpoints": [...]
//!     }
//!   }
//! }
//! ```

use anyhow::Result;
use serde::{Deserialize, Serialize};
use serde_json::Value;

/// Where this endpoint sits in the reachability graph.
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
#[serde(rename_all = "lowercase")]
pub enum EndpointScope {
    /// Public-facing relay (e.g. `https://wireup.net`). Crosses machines.
    Federation,
    /// Loopback-only relay (e.g. `http://127.0.0.1:8771`). Same-machine only.
    Local,
    /// LAN-bound relay (e.g. `http://192.168.1.50:8771`). Reachable from
    /// other machines on the same network without going through federation.
    /// v0.7.0-alpha.9: third scope for noble-creek-on-paul-mac ↔
    /// running-light-on-spark style across-the-room pairing without
    /// wireup.net hop. Visible to anyone who fetches the agent-card —
    /// opt-in per session (operator passes `--with-lan-relay <url>` at
    /// `wire session new` time).
    Lan,
    /// Unix Domain Socket (e.g. `unix:///path/to/local.sock`). Same-host,
    /// same-uid only. v0.7.0-alpha.16: framed primarily as a SECURITY
    /// boundary — no bound TCP port (no firewall surface), SO_PEERCRED
    /// kernel-attested peer uid (sister-session trust anchor), 0600
    /// socket permissions. Performance win over loopback HTTP is real
    /// but tiny (~1.3µs) and not the headline reason. Opt-in via
    /// `wire session new --with-uds`; Unix-only (Windows falls back to
    /// Local loopback).
    Uds,
}

/// One reachable address for a wire identity. Includes the bearer
/// `slot_token` because endpoints flow through the pair_drop body,
/// which is encrypted at protocol level (signed envelope + bilateral
/// pin gate from v0.5.14). Token is the slot's bearer credential; it
/// MUST stay private to the pair and is never published in the agent
/// card or phonebook.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Endpoint {
    pub relay_url: String,
    pub slot_id: String,
    pub slot_token: String,
    pub scope: EndpointScope,
}

impl Endpoint {
    pub fn federation(relay_url: String, slot_id: String, slot_token: String) -> Self {
        Self {
            relay_url,
            slot_id,
            slot_token,
            scope: EndpointScope::Federation,
        }
    }

    pub fn local(relay_url: String, slot_id: String, slot_token: String) -> Self {
        Self {
            relay_url,
            slot_id,
            slot_token,
            scope: EndpointScope::Local,
        }
    }

    /// v0.7.0-alpha.9: construct a LAN-scope endpoint.
    pub fn lan(relay_url: String, slot_id: String, slot_token: String) -> Self {
        Self {
            relay_url,
            slot_id,
            slot_token,
            scope: EndpointScope::Lan,
        }
    }

    /// v0.7.0-alpha.16: construct a UDS-scope endpoint.
    /// `relay_url` is a `unix:///abs/path/to/local.sock` URL (the
    /// `unix://` scheme is wire-internal; readers route to a UDS HTTP
    /// client rather than reqwest).
    pub fn uds(relay_url: String, slot_id: String, slot_token: String) -> Self {
        Self {
            relay_url,
            slot_id,
            slot_token,
            scope: EndpointScope::Uds,
        }
    }
}

/// Read all of a peer's pinned endpoints from `relay_state.json`,
/// sorted in routing priority order:
///
/// 1. Local endpoints first — only when we ALSO have a local slot
///    (i.e. our `self.endpoints` includes a local one with the same
///    relay_url). Otherwise local endpoints are skipped because we
///    can't reach them.
/// 2. Federation endpoints second.
///
/// RFC-006 Part B (#268): reads `endpoints[]` only — the single peer-routing
/// source. There is no flat-field synthesis fallback; a peer pin with no
/// `endpoints[]` array yields no endpoints (every real pin carries it).
pub fn peer_endpoints_in_priority_order(relay_state: &Value, peer_handle: &str) -> Vec<Endpoint> {
    let our_local_relay_url = relay_state
        .get("self")
        .and_then(|s| s.get("endpoints"))
        .and_then(Value::as_array)
        .and_then(|arr| {
            arr.iter()
                .find(|e| e.get("scope").and_then(Value::as_str) == Some("local"))
                .and_then(|e| e.get("relay_url"))
                .and_then(Value::as_str)
                .map(str::to_string)
        });

    let peer = match relay_state.get("peers").and_then(|p| p.get(peer_handle)) {
        Some(p) => p,
        None => return Vec::new(),
    };

    let mut all: Vec<Endpoint> = Vec::new();

    if let Some(arr) = peer.get("endpoints").and_then(Value::as_array) {
        for ep in arr {
            if let Ok(parsed) = serde_json::from_value::<Endpoint>(ep.clone()) {
                all.push(parsed);
            }
        }
    }

    // RFC-006 Part B: `endpoints[]` is the only peer-routing source. The
    // former flat-field synthesis fallback (for pre-v0.5.16 pins with no
    // `endpoints` array) is gone — every pin now carries `endpoints[]`
    // (`pin_peer_endpoints` writes it; invite-accept routes through it too).

    // Sort: UDS (same-host trust anchor) first, then local-loopback-
    // with-matching-self-local, then LAN (cross-machine same-network),
    // then federation. Drop unreachable scopes via the retain pass.
    //
    // v0.7.0-alpha.9: LAN endpoints sit between Local and Federation.
    // Faster than federation; not gated by "our_local matches" because
    // cross-machine peers won't have a matching our-local by definition.
    //
    // v0.7.0-alpha.16: UDS endpoints get rank 0 when peer + self share
    // a UDS socket path (we need to be able to connect to their socket
    // which means it must be readable by our uid). The "same-uid same-
    // host" sister-session trust shape this enforces is the whole
    // point of UDS — see project_wire_transport_substrate_research.
    let our_local = our_local_relay_url.clone();
    all.sort_by_key(|ep| match (ep.scope, &our_local) {
        (EndpointScope::Uds, _) => 0,
        (EndpointScope::Local, Some(our)) if &ep.relay_url == our => 1,
        (EndpointScope::Lan, _) => 2,
        (EndpointScope::Federation, _) => 3,
        _ => 4,
    });
    // Drop unreachable: Local needs matching loopback URL; UDS needs
    // the socket file to exist on our filesystem (the daemon-side
    // connect will surface a clearer error than a routing-time drop
    // would, but we still keep UDS in the routing list — failure
    // falls through to lower-priority scopes).
    all.retain(|ep| match (ep.scope, &our_local) {
        (EndpointScope::Local, None) => false,
        (EndpointScope::Local, Some(our)) => &ep.relay_url == our,
        (EndpointScope::Lan, _) => true,
        (EndpointScope::Uds, _) => true,
        (EndpointScope::Federation, _) => true,
    });
    all
}

/// All of OUR own endpoints from `relay_state.json`. Used by `cmd_push`
/// to find the local slot when routing local-first, and by the daemon's
/// pull loop to iterate every slot we should be reading from.
pub fn self_endpoints(relay_state: &Value) -> Vec<Endpoint> {
    let self_state = match relay_state.get("self") {
        Some(s) if !s.is_null() => s,
        _ => return Vec::new(),
    };
    let mut all: Vec<Endpoint> = Vec::new();
    if let Some(arr) = self_state.get("endpoints").and_then(Value::as_array) {
        for ep in arr {
            if let Ok(parsed) = serde_json::from_value::<Endpoint>(ep.clone()) {
                all.push(parsed);
            }
        }
    }
    if all.is_empty() {
        // Back-compat: synthesize a federation endpoint from legacy
        // top-level fields. Slot_token may be absent in some old
        // states; in that case the synthesized endpoint is partial
        // and downstream code must guard against empty token.
        let relay_url = self_state
            .get("relay_url")
            .and_then(Value::as_str)
            .unwrap_or("");
        let slot_id = self_state
            .get("slot_id")
            .and_then(Value::as_str)
            .unwrap_or("");
        let slot_token = self_state
            .get("slot_token")
            .and_then(Value::as_str)
            .unwrap_or("");
        if !relay_url.is_empty() && !slot_id.is_empty() {
            all.push(Endpoint::federation(
                relay_url.to_string(),
                slot_id.to_string(),
                slot_token.to_string(),
            ));
        }
    }
    all
}

/// v0.9 canonical single-reader for "my best inbound slot." Returns
/// the first endpoint from `self_endpoints()` — which is already
/// priority-ordered (UDS → Local-with-matching-self → LAN →
/// Federation) AND back-compat-falls-back to legacy top-level fields.
///
/// Replaces ad-hoc `self_state["relay_url"].as_str()` reads scattered
/// through the codebase. Pre-v0.9 those bare reads were the silent-
/// fail root cause: a session with only `self.endpoints[]` (no legacy
/// top-level fields) returned empty strings instead of the available
/// endpoint, and pair_drop_ack / pull / rotate-slot all silently
/// no-op'd. Always use this from new code.
pub fn self_primary_endpoint(relay_state: &Value) -> Option<Endpoint> {
    self_endpoints(relay_state).into_iter().next()
}

/// The single best (highest-priority) endpoint to reach `peer_handle`, or
/// `None` if the peer has no pinned endpoints. RFC-006 Part B: the canonical
/// replacement for reading the old flat `relay_url`/`slot_id`/`slot_token` peer
/// fields — every peer-pin reader resolves through this (or
/// `peer_endpoints_in_priority_order` when it needs failover).
pub fn peer_primary_endpoint(relay_state: &Value, peer_handle: &str) -> Option<Endpoint> {
    peer_endpoints_in_priority_order(relay_state, peer_handle)
        .into_iter()
        .next()
}

/// The `slot_token` of a peer's pinned **federation** endpoint on `relay_url`,
/// or `""` if there's no such endpoint (or it hasn't acked yet).
///
/// RFC-006 Part B: the canonical way to carry a peer's already-arrived reply
/// token forward across a re-pin. It replaces the old flat `peers[h].slot_token`
/// read — which Part B (#268) stopped *writing*, so any dial path still reading
/// it now reads `""` and silently wipes the peer's reply token on re-dial. Both
/// dial paths (`cli::pairing` and the MCP `tool_dial`) route through here so
/// they can't drift apart again.
pub fn peer_federation_token(relay_state: &Value, peer_handle: &str, relay_url: &str) -> String {
    relay_state
        .get("peers")
        .and_then(|p| p.get(peer_handle))
        .and_then(|e| e.get("endpoints"))
        .and_then(|a| serde_json::from_value::<Vec<Endpoint>>(a.clone()).ok())
        .unwrap_or_default()
        .into_iter()
        .find(|e| e.scope == EndpointScope::Federation && e.relay_url == relay_url)
        .map(|e| e.slot_token)
        .unwrap_or_default()
}

/// Pin a peer's full set of endpoints into `relay_state.json` under
/// `peers[handle]`. RFC-006 Part B (#268): writes `endpoints[]` ONLY — the
/// single peer-routing source. The flat `relay_url`/`slot_id`/`slot_token`
/// triple is no longer written. Durable non-routing fields
/// (`bilateral_completed_at`, `persona`, `profile`, `first_seen_at`,
/// `nostr_transport`) are preserved across re-pins (see below).
pub fn pin_peer_endpoints(
    relay_state: &mut Value,
    peer_handle: &str,
    endpoints: &[Endpoint],
) -> Result<()> {
    let peers = relay_state
        .as_object_mut()
        .map(|m| {
            m.entry("peers")
                .or_insert_with(|| Value::Object(Default::default()))
        })
        .ok_or_else(|| anyhow::anyhow!("relay_state.json root is not an object"))?
        .as_object_mut()
        .ok_or_else(|| anyhow::anyhow!("relay_state.peers is not an object"))?;
    // v0.14.2 (#162 fix #5): preserve durable peer state across re-pin
    // events. honey-pine observed `wire_peers` tier flapping
    // VERIFIED → PENDING_ACK; root cause is this `peers.insert(.., entry)`
    // wholesale-replacement losing any previously-set field. The fields
    // we explicitly retain here represent monotonic state — once
    // bilateral-pair is complete or the peer's published persona/profile
    // is known, those facts must NOT be wiped just because a fresh
    // pair_drop_ack carrying only endpoint data lands. Other fields
    // (`relay_url`, `slot_id`, `slot_token`, `endpoints`) are always
    // current-state and intentionally re-derived from the input below.
    let preserved: serde_json::Map<String, Value> = peers
        .get(peer_handle)
        .and_then(Value::as_object)
        .map(|m| {
            m.iter()
                .filter(|(k, _)| {
                    matches!(
                        k.as_str(),
                        "bilateral_completed_at"
                            | "persona"
                            | "profile"
                            | "first_seen_at"
                            // RFC-007 D3.4: a peer's Nostr transport coords are
                            // durable reachability state — must survive an
                            // HTTP-endpoint re-pin (same monotonic-state rule).
                            | "nostr_transport"
                    )
                })
                .map(|(k, v)| (k.clone(), v.clone()))
                .collect()
        })
        .unwrap_or_default();
    // RFC-006 Part B: `endpoints[]` is the SINGLE peer-routing source. The
    // top-level flat `relay_url`/`slot_id`/`slot_token` fields are no longer
    // written — they were a redundant synthesized copy (the "stale flat beats
    // fresh array" routing hazard). All peer-pin readers now resolve through
    // `peer_endpoints_in_priority_order`. (Self-slot flat is a separate
    // representation, untouched here.)
    let mut entry = preserved;
    entry.insert("endpoints".into(), serde_json::to_value(endpoints)?);
    peers.insert(peer_handle.to_string(), Value::Object(entry));
    Ok(())
}

/// RFC-007 D3.4: record a peer's **Nostr transport** reachability — their
/// x-only npub (hex) + a `wss://` relay to reach them on — under
/// `peers[handle].nostr_transport`. Read-modify-write so it composes with
/// `pin_peer_endpoints` (which preserves this field). Reachability only; trust
/// is a separate pin. Idempotent.
pub fn pin_peer_nostr_transport(
    relay_state: &mut Value,
    peer_handle: &str,
    npub_hex: &str,
    relay_url: &str,
) -> Result<()> {
    let peers = relay_state
        .as_object_mut()
        .map(|m| {
            m.entry("peers")
                .or_insert_with(|| Value::Object(Default::default()))
        })
        .ok_or_else(|| anyhow::anyhow!("relay_state.json root is not an object"))?
        .as_object_mut()
        .ok_or_else(|| anyhow::anyhow!("relay_state.peers is not an object"))?;
    let entry = peers
        .entry(peer_handle.to_string())
        .or_insert_with(|| Value::Object(Default::default()))
        .as_object_mut()
        .ok_or_else(|| anyhow::anyhow!("relay_state.peers[{peer_handle}] is not an object"))?;
    entry.insert(
        "nostr_transport".into(),
        serde_json::json!({ "npub": npub_hex, "relay": relay_url }),
    );
    Ok(())
}

/// Read a peer's Nostr transport coords `(npub_hex, relay_url)`, or `None` if
/// the peer has no Nostr transport recorded.
pub fn peer_nostr_transport(relay_state: &Value, peer_handle: &str) -> Option<(String, String)> {
    let nt = relay_state
        .get("peers")?
        .get(peer_handle)?
        .get("nostr_transport")?;
    let npub = nt.get("npub")?.as_str()?.to_string();
    let relay = nt.get("relay")?.as_str()?.to_string();
    if npub.is_empty() || relay.is_empty() {
        return None;
    }
    Some((npub, relay))
}

/// RFC-007 D3: record a Nostr relay this session is *reachable on* — one we've
/// paired/fetched over (`wire nostr pair/accept/fetch --relay X`). Persisted as
/// the distinct set `self.nostr_relays[]`. The daemon pull-loop reads this as
/// the authoritative "where do peers publish my inbound" set: a peer sends to me
/// by publishing to a relay *I'm* reachable on, which isn't necessarily a relay
/// *I* reach *them* on (the asymmetric case the peer-transport set misses).
/// Read-modify-write, idempotent (dedups).
pub fn pin_self_nostr_relay(relay_state: &mut Value, relay_url: &str) -> Result<()> {
    if relay_url.is_empty() {
        return Ok(());
    }
    let self_obj = relay_state
        .as_object_mut()
        .map(|m| {
            m.entry("self")
                .or_insert_with(|| Value::Object(Default::default()))
        })
        .ok_or_else(|| anyhow::anyhow!("relay_state.json root is not an object"))?
        .as_object_mut()
        .ok_or_else(|| anyhow::anyhow!("relay_state.self is not an object"))?;
    let arr = self_obj
        .entry("nostr_relays")
        .or_insert_with(|| Value::Array(Vec::new()))
        .as_array_mut()
        .ok_or_else(|| anyhow::anyhow!("relay_state.self.nostr_relays is not an array"))?;
    if !arr.iter().any(|v| v.as_str() == Some(relay_url)) {
        arr.push(Value::String(relay_url.to_string()));
    }
    Ok(())
}

/// The distinct Nostr relays this session is reachable on (`self.nostr_relays[]`).
/// Empty when never paired over Nostr.
pub fn self_nostr_relays(relay_state: &Value) -> Vec<String> {
    relay_state
        .get("self")
        .and_then(|s| s.get("nostr_relays"))
        .and_then(Value::as_array)
        .map(|a| {
            a.iter()
                .filter_map(|v| v.as_str())
                .filter(|s| !s.is_empty())
                .map(str::to_string)
                .collect()
        })
        .unwrap_or_default()
}

/// Infer an endpoint scope from a relay URL: `unix://` -> Uds, a loopback
/// host -> Local, otherwise Federation. LAN is never inferred (a private-
/// range IP is indistinguishable from a federation host by URL alone) and
/// must be requested explicitly.
pub fn infer_scope_from_url(url: &str) -> EndpointScope {
    if url.starts_with("unix://") {
        return EndpointScope::Uds;
    }
    let host = url
        .trim_start_matches("http://")
        .trim_start_matches("https://")
        .split('/')
        .next()
        .unwrap_or("")
        .split(':')
        .next()
        .unwrap_or("");
    if is_loopback_host(host) {
        EndpointScope::Local
    } else {
        EndpointScope::Federation
    }
}

/// True iff `host` (no scheme, no port) is a loopback address the E4 trust-path
/// gates treat as `Local` scope: `infer_scope_from_url`, the handle validator +
/// URL builder (`pair_profile::is_valid_domain` / `relay_url_for_domain`), and
/// the `is_known_relay_domain` phishing-warning suppression all key off THIS one
/// predicate so scheme + scope can never disagree. Keeping one predicate is
/// load-bearing: if these gates disagreed on "loopback", a handle could parse +
/// get an `http://` URL while being classified `Federation` (advertised off-box).
///
/// IPv4 `127.0.0.1` + `localhost` only. IPv6 `::1` is intentionally excluded — an
/// IPv6 authority needs bracketing (`[::1]:port`) the handle/URL path doesn't
/// carry, so `nick@::1:port` is rejected rather than half-accepted into a
/// malformed `http://::1:port`; use `127.0.0.1` for a loopback handle. Do not
/// broaden the IPv4 set to the full /8 here without updating every caller. (NB:
/// `session.rs::url_is_loopback` is a SEPARATE, deliberately-broader /8 predicate
/// for same-box session discovery — not a trust gate.)
pub fn is_loopback_host(host: &str) -> bool {
    host == "127.0.0.1" || host == "localhost"
}

/// True iff this endpoint set is reachable ONLY from the same box — every
/// endpoint resolves (by URL) to a loopback/`Local` or `Uds` address, with no
/// off-box `Federation`/LAN host. A peer pinned this way can't complete a
/// bilateral reply path with a *remote* peer: the reply has nowhere off-box to
/// land. This is the #277 honesty signal — `wire accept` reported
/// `bilateral_accepted` even when the resulting pin advertised only loopback
/// endpoints. Inferred from the URL (not the advertised `scope`) so a loopback
/// address mislabeled `federation` (exactly the #277 case) is still caught.
/// Empty set → false (no pin to judge).
pub fn endpoints_are_local_only(endpoints: &[Endpoint]) -> bool {
    !endpoints.is_empty()
        && endpoints.iter().all(|e| {
            matches!(
                infer_scope_from_url(&e.relay_url),
                EndpointScope::Local | EndpointScope::Uds
            )
        })
}

/// Build the `self` block for `relay_state.json` from an endpoint set:
/// the additive `endpoints[]` array plus legacy top-level
/// relay_url/slot_id/slot_token pointing at the federation endpoint (or,
/// absent one, the first endpoint) for v0.5.16-and-earlier back-compat.
fn build_self_value(eps: &[Endpoint]) -> Value {
    let legacy = eps
        .iter()
        .find(|e| e.scope == EndpointScope::Federation)
        .or_else(|| eps.first());
    let mut self_obj = serde_json::Map::new();
    if let Some(l) = legacy {
        self_obj.insert("relay_url".into(), Value::String(l.relay_url.clone()));
        self_obj.insert("slot_id".into(), Value::String(l.slot_id.clone()));
        self_obj.insert("slot_token".into(), Value::String(l.slot_token.clone()));
    }
    self_obj.insert(
        "endpoints".into(),
        serde_json::to_value(eps).unwrap_or(Value::Null),
    );
    Value::Object(self_obj)
}

/// Insert-or-replace one of OUR OWN endpoints in `relay_state["self"]`,
/// keyed by `relay_url` (re-binding the same relay updates it in place).
/// ADDITIVE: every other existing self endpoint is preserved, so an agent
/// can hold a local relay AND a federation relay at once. Rebuilds the
/// legacy top-level fields. Single source of truth for the self-slot write
/// shape — used by `cmd_bind_relay` and `init_self_idempotent`.
pub fn upsert_self_endpoint(relay_state: &mut Value, ep: Endpoint) {
    let mut eps = self_endpoints(relay_state);
    eps.retain(|e| e.relay_url != ep.relay_url);
    eps.push(ep);
    relay_state["self"] = build_self_value(&eps);
}

#[cfg(test)]
mod tests {
    use super::*;
    use serde_json::json;

    #[test]
    fn infer_scope_classifies_loopback_unix_and_federation() {
        assert_eq!(
            infer_scope_from_url("http://127.0.0.1:8771"),
            EndpointScope::Local
        );
        assert_eq!(
            infer_scope_from_url("http://localhost:8771"),
            EndpointScope::Local
        );
        assert_eq!(
            infer_scope_from_url("unix:///tmp/wire.sock"),
            EndpointScope::Uds
        );
        assert_eq!(
            infer_scope_from_url("https://wireup.net"),
            EndpointScope::Federation
        );
    }

    #[test]
    fn upsert_self_endpoint_is_additive_then_updates_in_place() {
        let mut state = json!({});
        upsert_self_endpoint(
            &mut state,
            Endpoint::federation("https://wireup.net".into(), "fed1".into(), "ft".into()),
        );
        upsert_self_endpoint(
            &mut state,
            Endpoint::local("http://127.0.0.1:8771".into(), "loc1".into(), "lt".into()),
        );
        // Both kept.
        assert_eq!(self_endpoints(&state).len(), 2);
        // Legacy fields point at federation.
        assert_eq!(state["self"]["relay_url"], "https://wireup.net");
        // Re-binding the same relay replaces that one entry, not appends.
        upsert_self_endpoint(
            &mut state,
            Endpoint::local("http://127.0.0.1:8771".into(), "loc2".into(), "lt2".into()),
        );
        let eps = self_endpoints(&state);
        assert_eq!(eps.len(), 2, "same-relay rebind replaces, not appends");
        let loc = eps
            .iter()
            .find(|e| e.scope == EndpointScope::Local)
            .unwrap();
        assert_eq!(loc.slot_id, "loc2", "local slot updated in place");
    }

    #[test]
    fn peer_endpoints_ignores_flat_only_pin_post_rfc006() {
        // RFC-006 Part B: `endpoints[]` is the single peer-routing source. A
        // peer with ONLY the old flat fields and no `endpoints[]` array yields
        // NO endpoints — the synthesis fallback was removed. (No users to
        // migrate; every real pin now carries `endpoints[]`.)
        let state = json!({
            "peers": {
                "alice": { "relay_url": "https://wireup.net", "slot_id": "abc", "slot_token": "tok" }
            }
        });
        assert!(peer_endpoints_in_priority_order(&state, "alice").is_empty());
    }

    #[test]
    fn self_nostr_relay_roundtrips_and_dedups() {
        let mut state = json!({});
        pin_self_nostr_relay(&mut state, "wss://r1").unwrap();
        pin_self_nostr_relay(&mut state, "wss://r2").unwrap();
        pin_self_nostr_relay(&mut state, "wss://r1").unwrap(); // dup → no-op
        pin_self_nostr_relay(&mut state, "").unwrap(); // empty → no-op
        assert_eq!(
            self_nostr_relays(&state),
            vec!["wss://r1".to_string(), "wss://r2".to_string()]
        );
        // Composes with an existing self block (doesn't clobber other self keys).
        let mut state2 = json!({"self": {"relay_url": "https://wireup.net", "slot_id": "s"}});
        pin_self_nostr_relay(&mut state2, "wss://x").unwrap();
        assert_eq!(state2["self"]["relay_url"], "https://wireup.net");
        assert_eq!(self_nostr_relays(&state2), vec!["wss://x".to_string()]);
        // Absent → empty.
        assert!(self_nostr_relays(&json!({})).is_empty());
    }

    #[test]
    fn endpoints_are_local_only_catches_loopback_pin_incl_mislabeled_scope() {
        // Empty → false (nothing to judge).
        assert!(!endpoints_are_local_only(&[]));
        // A loopback URL mislabeled `federation` (the #277 case) is still caught
        // — we infer from the URL, not the advertised scope.
        let mislabeled =
            Endpoint::federation("http://127.0.0.1:18791".into(), "s".into(), "t".into());
        assert!(endpoints_are_local_only(std::slice::from_ref(&mislabeled)));
        // A real federation host → reachable, not local-only.
        let fed = Endpoint::federation("https://wireup.net".into(), "s".into(), "t".into());
        assert!(!endpoints_are_local_only(std::slice::from_ref(&fed)));
        // Mixed (loopback + federation) → reachable off-box via the federation one.
        assert!(!endpoints_are_local_only(&[mislabeled.clone(), fed]));
        // UDS is same-host only → local-only.
        let uds = Endpoint::uds("unix:///tmp/wire.sock".into(), "s".into(), "t".into());
        assert!(endpoints_are_local_only(&[uds]));
    }

    #[test]
    fn peer_federation_token_carries_forward_from_endpoints_not_flat() {
        // RFC-006 Part B regression: re-dial must carry the peer's already-acked
        // reply token forward from `endpoints[]`. Reading the old flat
        // `slot_token` (which Part B stopped writing) returned "" and wiped it.
        let state = json!({
            "peers": {
                "alice": {
                    // A stale flat field must NOT be the source of truth...
                    "slot_token": "STALE_FLAT",
                    "endpoints": [
                        {"relay_url": "https://wireup.net", "slot_id": "s1", "slot_token": "REAL_TOK", "scope": "federation"},
                        {"relay_url": "http://127.0.0.1:8771", "slot_id": "l1", "slot_token": "LOCAL_TOK", "scope": "local"}
                    ]
                }
            }
        });
        // ...the federation endpoint's token on the matching relay is.
        assert_eq!(
            peer_federation_token(&state, "alice", "https://wireup.net"),
            "REAL_TOK"
        );
        // A different relay (no matching federation endpoint) → empty, not the
        // local token and not the stale flat field.
        assert_eq!(
            peer_federation_token(&state, "alice", "https://other.example"),
            ""
        );
        // Unknown peer → empty.
        assert_eq!(
            peer_federation_token(&state, "nobody", "https://wireup.net"),
            ""
        );
    }

    #[test]
    fn peer_endpoints_lan_beats_federation() {
        // v0.7.0-alpha.9: when a peer publishes both Lan and Federation
        // endpoints (and we have a matching local too), priority must be
        // Local(matched) > Lan > Federation. Lan is cross-machine same-
        // network, faster than federation but not as fast as loopback.
        let state = json!({
            "self": {
                "endpoints": [
                    {"relay_url": "http://127.0.0.1:8771", "slot_id": "self-loop", "slot_token": "t1", "scope": "local"},
                    {"relay_url": "https://wireup.net", "slot_id": "self-fed", "slot_token": "t2", "scope": "federation"}
                ]
            },
            "peers": {
                "alice": {
                    "endpoints": [
                        {"relay_url": "https://wireup.net", "slot_id": "a-fed", "slot_token": "ta-f", "scope": "federation"},
                        {"relay_url": "http://192.168.1.50:8771", "slot_id": "a-lan", "slot_token": "ta-l", "scope": "lan"},
                        {"relay_url": "http://127.0.0.1:8771", "slot_id": "a-loop", "slot_token": "ta-loop", "scope": "local"}
                    ]
                }
            }
        });
        let eps = peer_endpoints_in_priority_order(&state, "alice");
        assert_eq!(
            eps.len(),
            3,
            "Local(matched) + Lan + Federation all reachable"
        );
        assert_eq!(
            eps[0].scope,
            EndpointScope::Local,
            "loopback wins (same-machine)"
        );
        assert_eq!(
            eps[1].scope,
            EndpointScope::Lan,
            "Lan second (same-network)"
        );
        assert_eq!(
            eps[2].scope,
            EndpointScope::Federation,
            "Federation last (anywhere)"
        );
    }

    #[test]
    fn peer_endpoints_lan_kept_when_self_has_no_local() {
        // Cross-machine peer scenario: we have no Local, peer has Lan
        // and Federation. Lan must still be kept (we connect TO their
        // LAN address; we don't need a Local of our own to do so).
        let state = json!({
            "self": {
                "endpoints": [
                    {"relay_url": "https://wireup.net", "slot_id": "self-fed", "slot_token": "t1", "scope": "federation"}
                ]
            },
            "peers": {
                "alice": {
                    "endpoints": [
                        {"relay_url": "https://wireup.net", "slot_id": "a-fed", "slot_token": "ta-f", "scope": "federation"},
                        {"relay_url": "http://192.168.1.50:8771", "slot_id": "a-lan", "slot_token": "ta-l", "scope": "lan"}
                    ]
                }
            }
        });
        let eps = peer_endpoints_in_priority_order(&state, "alice");
        assert_eq!(eps.len(), 2);
        assert_eq!(
            eps[0].scope,
            EndpointScope::Lan,
            "Lan preferred over Federation"
        );
        assert_eq!(eps[1].scope, EndpointScope::Federation);
    }

    #[test]
    fn pin_peer_endpoints_writes_no_flat_fields_post_rfc006() {
        // RFC-006 Part B: pin writes `endpoints[]` ONLY — no synthesized
        // top-level relay_url/slot_id/slot_token. Routing reads the array.
        let mut state = json!({});
        let endpoints = vec![
            Endpoint::lan(
                "http://192.168.1.50:8771".to_string(),
                "lan-slot".to_string(),
                "lan-tok".to_string(),
            ),
            Endpoint::local(
                "http://127.0.0.1:8771".to_string(),
                "loop-slot".to_string(),
                "loop-tok".to_string(),
            ),
        ];
        pin_peer_endpoints(&mut state, "alice", &endpoints).unwrap();
        let alice = &state["peers"]["alice"];
        assert!(alice.get("relay_url").is_none(), "no flat relay_url");
        assert!(alice.get("slot_id").is_none(), "no flat slot_id");
        assert!(alice.get("slot_token").is_none(), "no flat slot_token");
        assert_eq!(
            alice["endpoints"].as_array().map(Vec::len),
            Some(2),
            "endpoints[] is the routing source"
        );
    }

    #[test]
    fn peer_endpoints_orders_local_first_when_self_has_matching_local() {
        let state = json!({
            "self": {
                "endpoints": [
                    {"relay_url": "https://wireup.net",    "slot_id": "self-fed",  "slot_token": "t1", "scope": "federation"},
                    {"relay_url": "http://127.0.0.1:8771", "slot_id": "self-loop", "slot_token": "t2", "scope": "local"}
                ]
            },
            "peers": {
                "alice": {
                    "endpoints": [
                        {"relay_url": "https://wireup.net",    "slot_id": "a-fed",  "slot_token": "ta1", "scope": "federation"},
                        {"relay_url": "http://127.0.0.1:8771", "slot_id": "a-loop", "slot_token": "ta2", "scope": "local"}
                    ]
                }
            }
        });
        let eps = peer_endpoints_in_priority_order(&state, "alice");
        assert_eq!(eps.len(), 2);
        assert_eq!(eps[0].scope, EndpointScope::Local);
        assert_eq!(eps[1].scope, EndpointScope::Federation);
    }

    #[test]
    fn peer_endpoints_drops_local_when_self_has_no_local() {
        let state = json!({
            "self": {
                "endpoints": [
                    {"relay_url": "https://wireup.net", "slot_id": "self-fed", "slot_token": "t1", "scope": "federation"}
                ]
            },
            "peers": {
                "alice": {
                    "endpoints": [
                        {"relay_url": "https://wireup.net",    "slot_id": "a-fed",  "slot_token": "ta1", "scope": "federation"},
                        {"relay_url": "http://127.0.0.1:8771", "slot_id": "a-loop", "slot_token": "ta2", "scope": "local"}
                    ]
                }
            }
        });
        let eps = peer_endpoints_in_priority_order(&state, "alice");
        // Only federation reachable: local was filtered.
        assert_eq!(eps.len(), 1);
        assert_eq!(eps[0].scope, EndpointScope::Federation);
    }

    #[test]
    fn peer_endpoints_drops_local_when_relay_urls_dont_match() {
        let state = json!({
            "self": {
                "endpoints": [
                    {"relay_url": "http://127.0.0.1:8771", "slot_id": "self-loop", "slot_token": "t2", "scope": "local"}
                ]
            },
            "peers": {
                "alice": {
                    "endpoints": [
                        {"relay_url": "http://127.0.0.1:9999", "slot_id": "a-loop", "slot_token": "ta2", "scope": "local"}
                    ]
                }
            }
        });
        // Our local is :8771, peer's local is :9999 — can't route there.
        let eps = peer_endpoints_in_priority_order(&state, "alice");
        assert_eq!(
            eps.len(),
            0,
            "different local relays cannot reach each other"
        );
    }

    #[test]
    fn pin_then_resolve_round_trips_through_endpoints_array() {
        // RFC-006 Part B: pin writes endpoints[]; routing resolves from it
        // (priority order), with NO flat fields involved on either side.
        let mut state = json!({"peers": {}});
        let endpoints = vec![
            Endpoint::federation("https://wireup.net".into(), "abc".into(), "tok".into()),
            Endpoint::local(
                "http://127.0.0.1:8771".into(),
                "loop".into(),
                "loop-tok".into(),
            ),
        ];
        pin_peer_endpoints(&mut state, "alice", &endpoints).unwrap();
        let alice = &state["peers"]["alice"];
        assert!(alice.get("relay_url").is_none(), "no flat fields written");
        assert_eq!(alice["endpoints"].as_array().map(Vec::len), Some(2));
        // Resolve from the array (no flat). Without a matching self-local relay,
        // the peer's loopback endpoint isn't reachable for us, so federation is
        // the primary route.
        // Priority order drops the unreachable loopback (no matching
        // self-local), leaving the federation route.
        let ordered = peer_endpoints_in_priority_order(&state, "alice");
        assert_eq!(ordered.len(), 1, "only the reachable federation route");
        let primary = peer_primary_endpoint(&state, "alice").unwrap();
        assert_eq!(primary.scope, EndpointScope::Federation);
        assert_eq!(primary.slot_id, "abc");
    }

    #[test]
    fn self_endpoints_back_compat_falls_back_to_legacy_fields() {
        let state = json!({
            "self": {
                "relay_url": "https://wireup.net",
                "slot_id": "self-fed",
                "slot_token": "t1"
            }
        });
        let eps = self_endpoints(&state);
        assert_eq!(eps.len(), 1);
        assert_eq!(eps[0].scope, EndpointScope::Federation);
        assert_eq!(eps[0].slot_id, "self-fed");
    }

    #[test]
    fn self_endpoints_returns_both_when_dual_slot() {
        let state = json!({
            "self": {
                "endpoints": [
                    {"relay_url": "https://wireup.net",    "slot_id": "self-fed",  "slot_token": "t1", "scope": "federation"},
                    {"relay_url": "http://127.0.0.1:8771", "slot_id": "self-loop", "slot_token": "t2", "scope": "local"}
                ]
            }
        });
        let eps = self_endpoints(&state);
        assert_eq!(eps.len(), 2);
    }

    // ── RFC-007 D3.4: per-peer Nostr transport reachability ──
    #[test]
    fn nostr_transport_roundtrips() {
        let mut state = serde_json::json!({});
        let npub = "a".repeat(64);
        pin_peer_nostr_transport(&mut state, "raven-kettle", &npub, "wss://relay.damus.io")
            .unwrap();
        assert_eq!(
            peer_nostr_transport(&state, "raven-kettle"),
            Some((npub.clone(), "wss://relay.damus.io".to_string()))
        );
        // Unknown peer → None.
        assert_eq!(peer_nostr_transport(&state, "nobody"), None);
    }

    #[test]
    fn nostr_transport_survives_endpoint_repin() {
        // The #162 hazard: a later HTTP-endpoint pin must NOT wipe the recorded
        // Nostr transport (it's monotonic reachability state).
        let mut state = serde_json::json!({});
        let npub = "b".repeat(64);
        pin_peer_nostr_transport(&mut state, "p", &npub, "wss://nos.lol").unwrap();
        pin_peer_endpoints(
            &mut state,
            "p",
            &[Endpoint::federation(
                "https://wireup.net".into(),
                "slot1".into(),
                "tok1".into(),
            )],
        )
        .unwrap();
        // Both survive.
        assert_eq!(
            peer_nostr_transport(&state, "p"),
            Some((npub, "wss://nos.lol".to_string()))
        );
        assert_eq!(peer_endpoints_in_priority_order(&state, "p").len(), 1);
    }

    #[test]
    fn nostr_transport_is_idempotent_and_updatable() {
        let mut state = serde_json::json!({});
        pin_peer_nostr_transport(&mut state, "p", &"c".repeat(64), "wss://a").unwrap();
        // Re-record with a new relay → updates.
        pin_peer_nostr_transport(&mut state, "p", &"c".repeat(64), "wss://b").unwrap();
        assert_eq!(
            peer_nostr_transport(&state, "p"),
            Some(("c".repeat(64), "wss://b".to_string()))
        );
    }
}