From 60be04925ea67440360337f37c1959b4bf1ed98c Mon Sep 17 00:00:00 2001
From: Lars Strojny <lars@strojny.net>
Date: Mon, 7 Nov 2022 19:30:55 +0100
Subject: [PATCH] Fix Promise issue

---
 src/discovery/hap_node_js_client.ts | 94 +++++++++++++++++++----------
 src/platform.ts                     |  1 +
 2 files changed, 62 insertions(+), 33 deletions(-)

diff --git a/src/discovery/hap_node_js_client.ts b/src/discovery/hap_node_js_client.ts
index 969fc34..36ab875 100644
--- a/src/discovery/hap_node_js_client.ts
+++ b/src/discovery/hap_node_js_client.ts
@@ -1,45 +1,73 @@
-import type { HapDiscover } from './api'
-import { HAPNodeJSClient } from 'hap-node-client'
+import type {HapDiscover} from './api'
+import {HAPNodeJSClient} from 'hap-node-client'
 
-import { Device, DeviceBoundary } from '../boundaries'
-import { Array, Unknown } from 'runtypes'
+import {Device, DeviceBoundary} from '../boundaries'
+import {Array, Unknown} from 'runtypes'
+import {Logger} from "homebridge";
 
 const MaybeDevices = Array(Unknown)
 
-export const discover: HapDiscover = ({ pin, refreshInterval, discoveryTimeout, requestTimeout, logger, debug }) => {
+type HapConfig = {
+    debug: boolean
+    refresh: number
+    timeout: number
+    reqTimeout: number
+    pin: string
+}
+type HapClient = typeof HAPNodeJSClient
+type ResolveFunc = (devices: Device[]) => void
+type RejectFunc = (error: unknown) => void
+
+const clientMap: Record<string,HapClient> = {}
+const promiseMap: Record<string,[ResolveFunc,RejectFunc]> = {}
+
+function startDiscovery(logger: Logger, config: HapConfig, resolve: ResolveFunc, reject: RejectFunc) {
+    const key = JSON.stringify(config)
+
+    if (!clientMap[key]) {
+        logger.debug('Creating new HAP client')
+        const client = new HAPNodeJSClient(config)
+        client.on('Ready', (deviceData: unknown) => {
+            try {
+                const devices: Device[] = []
+
+                for (const device of MaybeDevices.check(deviceData)) {
+                    try {
+                        devices.push(DeviceBoundary.check(device))
+                    } catch (e) {
+                        logger.error(
+                            'Boundary check for device data failed %o %s',
+                            e,
+                            JSON.stringify(device, null, 4),
+                        )
+                    }
+                }
+
+                if (promiseMap[key]) promiseMap[key][0](devices)
+            } catch (e) {
+                if (promiseMap[key]) promiseMap[key][1](e)
+            }
+        })
+        clientMap[key] = client
+    } else {
+        logger.debug('Reusing existing HAP client')
+    }
+    promiseMap[key] = [resolve, reject]
+}
+
+export const discover: HapDiscover = ({pin, refreshInterval, discoveryTimeout, requestTimeout, logger, debug}) => {
     return new Promise((resolve, reject) => {
-        try {
-            const client = new HAPNodeJSClient({
+        startDiscovery(
+            logger,
+            {
                 debug: debug,
                 refresh: refreshInterval,
                 timeout: discoveryTimeout,
                 reqTimeout: requestTimeout,
                 pin,
-            })
-
-            client.on('Ready', (deviceData: unknown) => {
-                try {
-                    const devices: Device[] = []
-
-                    for (const device of MaybeDevices.check(deviceData)) {
-                        try {
-                            devices.push(DeviceBoundary.check(device))
-                        } catch (e) {
-                            logger.error(
-                                'Boundary check for device data failed %o %s',
-                                e,
-                                JSON.stringify(device, null, 4),
-                            )
-                        }
-                    }
-
-                    resolve(devices)
-                } catch (e) {
-                    reject(e)
-                }
-            })
-        } catch (e) {
-            reject(e)
-        }
+            },
+            resolve,
+            reject
+        )
     })
 }
diff --git a/src/platform.ts b/src/platform.ts
index 5903190..bcd2e79 100644
--- a/src/platform.ts
+++ b/src/platform.ts
@@ -112,6 +112,7 @@ export class PrometheusExporterPlatform implements IndependentPlatformPlugin {
                 this.metrics = aggregate(devices)
                 this.metricsDiscovered = true
                 this.log.debug('HAP discovery completed, %d metrics discovered', this.metrics.length)
+                this.startHapDiscovery()
             })
             .catch((e) => {
                 this.log.error('HAP discovery error', e)