fix(ospf): показать конфликт состояний OSPF и BFD

lib/ospf-state.ts

@@ -12,3 +12,18 @@ export function ospfNodeState(states: OspfNeighborState[]): "Full" | "2-Way" | "
   if (states.some(state => state !== "Down")) return "Pending"
   return "Down"
 }
+
+/** Correlate only a single observed direct BFD session on an explicitly configured interface. */
+export function ospfBfdConflicts<T extends { localRouter: string; localIface: string; neighborAddress?: string; state: OspfNeighborState; dataUnknown?: boolean }>(
+  neighbors: T[],
+  interfaces: Array<{ serverId: string; interfaceName: string; useBfd?: boolean | null; active?: boolean | null; dataUnknown?: boolean }>,
+  sessions: Array<{ serverId: string; iface: string; remoteAddr: string; state: BfdState; multihop?: boolean | null; dataUnknown?: boolean }>,
+): T[] {
+  const ip = (value: string) => value.split("%")[0]?.toLowerCase() ?? ""
+  return neighbors.filter(n => {
+    if (n.dataUnknown || n.state !== "Full" || !n.neighborAddress || !n.localIface) return false
+    if (!interfaces.some(i => !i.dataUnknown && i.active === true && i.useBfd === true && i.serverId === n.localRouter && i.interfaceName === n.localIface)) return false
+    const matching = sessions.filter(s => !s.dataUnknown && s.multihop === false && s.serverId === n.localRouter && s.iface === n.localIface && ip(s.remoteAddr) === ip(n.neighborAddress!))
+    return matching.length === 1 && (matching[0]!.state === "Down" || matching[0]!.state === "AdminDown")
+  })
+}