From d484a15c895a96407eaec7b85553476842e68794 Mon Sep 17 00:00:00 2001
From: Josh Creek <8179928+jcreek@users.noreply.github.com>
Date: Sun, 22 Feb 2026 14:03:01 +0000
Subject: [PATCH] fix(#2): harden network data parsing and link resolution

---
 src/lib/data/loadNetworkData.ts       | 10 ++++++++-
 src/lib/graph/transformNetworkData.ts | 29 +++++++++++++++++++++------
 src/lib/types.ts                      | 10 ++++-----
 3 files changed, 37 insertions(+), 12 deletions(-)

diff --git a/src/lib/data/loadNetworkData.ts b/src/lib/data/loadNetworkData.ts
index a5a5b82..b5be388 100644
--- a/src/lib/data/loadNetworkData.ts
+++ b/src/lib/data/loadNetworkData.ts
@@ -20,7 +20,15 @@ export default async function loadNetworkData(jsonPath: string): Promise<Network
 		throw new Error(`Failed to load ${jsonPath} (${response.status} ${response.statusText})`);
 	}
 
-	const rawData: unknown = await response.json();
+	let rawData: unknown;
+	try {
+		rawData = await response.json();
+	} catch (error) {
+		throw new Error(`Failed to parse JSON at ${jsonPath}`, {
+			cause: error
+		});
+	}
+
 	if (!isNetworkData(rawData)) {
 		throw new Error(`JSON at ${jsonPath} is not valid network data`);
 	}
diff --git a/src/lib/graph/transformNetworkData.ts b/src/lib/graph/transformNetworkData.ts
index 02e18d4..849593c 100644
--- a/src/lib/graph/transformNetworkData.ts
+++ b/src/lib/graph/transformNetworkData.ts
@@ -2,11 +2,16 @@ import type { ConnectedPortRef, NetworkData, Port } from '../types';
 import type { GraphEdgeElement, GraphNodeElement, GraphTransformResult } from './types';
 
 interface EndpointOwner {
+	kind: 'machine' | 'device';
 	nodeId: string;
 	name: string;
 	ports: Map<string, Port>;
 }
 
+function toOwnerKey(kind: EndpointOwner['kind'], name: string): string {
+	return `${kind}:${name}`;
+}
+
 function toMachineNodeId(name: string): string {
 	return `machine:${encodeURIComponent(name)}`;
 }
@@ -58,7 +63,7 @@ export function transformNetworkDataToGraph(data: NetworkData): GraphTransformRe
 			vmCount: number;
 		}
 	> = {};
-	const ownersByName = new Map<string, EndpointOwner>();
+	const ownersByKey = new Map<string, EndpointOwner>();
 	const seenWarnings = new Set<string>();
 
 	const warn = (message: string) => {
@@ -69,13 +74,14 @@ export function transformNetworkDataToGraph(data: NetworkData): GraphTransformRe
 	};
 
 	const addOwner = (owner: EndpointOwner) => {
-		if (ownersByName.has(owner.name)) {
+		const ownerKey = toOwnerKey(owner.kind, owner.name);
+		if (ownersByKey.has(ownerKey)) {
 			warn(
-				`Duplicate node name "${owner.name}" found. First occurrence will be used for link resolution.`
+				`Duplicate ${owner.kind} name "${owner.name}" found. First occurrence will be used for link resolution.`
 			);
 			return;
 		}
-		ownersByName.set(owner.name, owner);
+		ownersByKey.set(ownerKey, owner);
 	};
 
 	let hostingEdgeCounter = 0;
@@ -163,6 +169,7 @@ export function transformNetworkDataToGraph(data: NetworkData): GraphTransformRe
 		}
 
 		addOwner({
+			kind: 'machine',
 			nodeId: machineNodeId,
 			name: machine.machineName,
 			ports: machinePorts
@@ -198,6 +205,7 @@ export function transformNetworkDataToGraph(data: NetworkData): GraphTransformRe
 		}
 
 		addOwner({
+			kind: 'device',
 			nodeId: deviceNodeId,
 			name: device.name,
 			ports: devicePortMap
@@ -207,12 +215,21 @@ export function transformNetworkDataToGraph(data: NetworkData): GraphTransformRe
 	const seenPhysicalConnections = new Set<string>();
 	let physicalEdgeCounter = 0;
 
-	for (const owner of ownersByName.values()) {
+	for (const owner of ownersByKey.values()) {
 		for (const port of owner.ports.values()) {
 			const connectedTo = parseConnectedTo(port.connectedTo);
 			if (!connectedTo) continue;
 
-			const targetOwner = ownersByName.get(connectedTo.device);
+			const machineTargetOwner = ownersByKey.get(toOwnerKey('machine', connectedTo.device));
+			const deviceTargetOwner = ownersByKey.get(toOwnerKey('device', connectedTo.device));
+			if (machineTargetOwner && deviceTargetOwner) {
+				warn(
+					`Link from "${owner.name}:${port.portName}" references ambiguous device "${connectedTo.device}" (matches both machine and device names).`
+				);
+				continue;
+			}
+
+			const targetOwner = machineTargetOwner ?? deviceTargetOwner;
 			if (!targetOwner) {
 				warn(
 					`Link from "${owner.name}:${port.portName}" references unknown device "${connectedTo.device}".`
diff --git a/src/lib/types.ts b/src/lib/types.ts
index d467406..2fb4293 100644
--- a/src/lib/types.ts
+++ b/src/lib/types.ts
@@ -1,14 +1,14 @@
+export interface ConnectedPortRef {
+	device: string;
+	port: string;
+}
+
 export interface Port {
 	portName: string;
 	speedGbps?: number; // default to 1 if not provided
 	connectedTo?: ConnectedPortRef;
 }
 
-export interface ConnectedPortRef {
-	device: string;
-	port: string;
-}
-
 export interface Hardware {
 	cpu: string;
 	ram: string;