1 files changed, 72 insertions, 0 deletions
diff --git a/src/device.ts b/src/device.ts
new file mode 100644
index 0000000..1c0d0ea
--- /dev/null
+++ b/src/device.ts
@@ -0,0 +1,72 @@
+import { NodeId } from "@matter/main";
+import type { CommissioningController } from "@project-chip/matter.js";
+import { NodeStates, type PairedNode } from "@project-chip/matter.js/device";
+import { Log } from "./logging.js";
+
+const log = new Log("device");
+
+export function nodeStateName(state: NodeStates): string {
+  switch (state) {
+    case NodeStates.Connected:
+      return "connected";
+    case NodeStates.Disconnected:
+      return "disconnected";
+    case NodeStates.Reconnecting:
+      return "reconnecting";
+    case NodeStates.WaitingForDeviceDiscovery:
+      return "waiting for device discovery";
+  }
+}
+
+/**
+ * Connects to the commissioned node using operational discovery (DNS-SD by
+ * node identity, never a stored IP address) and waits until the node is fully
+ * initialized from the device.
+ *
+ * The returned PairedNode keeps reconnecting in the background; observe
+ * `events.stateChanged` for connectivity transitions.
+ */
+export async function connectDevice(
+  controller: CommissioningController,
+  nodeId: bigint,
+  timeoutMs = 60_000,
+): Promise<PairedNode> {
+  const node = await controller.getNode(NodeId(nodeId));
+
+  node.events.stateChanged.on(state => {
+    log.debug(`Node ${nodeId} state: ${nodeStateName(state)}`);
+  });
+
+  if (!node.initialized) {
+    log.info(`Connecting to Matter node ${nodeId}...`);
+    node.connect();
+    await waitForInitialization(node, nodeId, timeoutMs);
+  } else if (!node.isConnected) {
+    node.connect();
+    await waitForInitialization(node, nodeId, timeoutMs);
+  }
+
+  log.info(`Connected to Matter node ${nodeId}`);
+  return node;
+}
+
+async function waitForInitialization(node: PairedNode, nodeId: bigint, timeoutMs: number): Promise<void> {
+  let timer: NodeJS.Timeout | undefined;
+  const timeout = new Promise<never>((_, reject) => {
+    timer = setTimeout(
+      () =>
+        reject(
+          new Error(
+            `Timed out after ${Math.round(timeoutMs / 1000)}s waiting for node ${nodeId}. ` +
+              `The device may be offline or unreachable over IPv6.`,
+          ),
+        ),
+      timeoutMs,
+    );
+  });
+  try {
+    await Promise.race([node.events.initializedFromRemote, timeout]);
+  } finally {
+    clearTimeout(timer);
+  }
+}