Check day every hour

home-assistant · May 12, 2023 · dfe79fd · dfe79fd
1 parent 3bfbb6f
commit dfe79fd
Showing 1 changed file with 29 additions and 3 deletions.
diff --git a/src/components/ha-absolute-time.ts b/src/components/ha-absolute-time.ts
@@ -4,6 +4,9 @@ import { customElement, property } from "lit/decorators";
 import { absoluteTime } from "../common/datetime/absolute_time";
 import type { HomeAssistant } from "../types";
 
+const ONE_HOUR = 60 * 60 * 1000;
+const SAFE_MARGIN = 5 * 1000;
+
 @customElement("ha-absolute-time")
 class HaAbsoluteTime extends ReactiveElement {
   @property({ attribute: false }) public hass!: HomeAssistant;
@@ -12,17 +15,20 @@ class HaAbsoluteTime extends ReactiveElement {
 
   private _lastUpdate?: Date;
 
+  private _timeout?: number;
+
   private _interval?: number;
 
   public disconnectedCallback(): void {
     super.disconnectedCallback();
+    this._clearTimeout();
     this._clearInterval();
   }
 
   public connectedCallback(): void {
     super.connectedCallback();
     if (this.datetime) {
-      this._startInterval();
+      this._startTimeout();
     }
   }
 
@@ -40,6 +46,26 @@ class HaAbsoluteTime extends ReactiveElement {
     this._updateAbsolute();
   }
 
+  private _clearTimeout(): void {
+    if (this._interval) {
+      window.clearTimeout(this._timeout);
+      this._timeout = undefined;
+    }
+  }
+
+  private _startTimeout(): void {
+    this._clearInterval();
+    this._clearTimeout();
+
+    const msToNextHour =
+      ONE_HOUR - (new Date().getTime() % ONE_HOUR) + SAFE_MARGIN;
+
+    this._timeout = window.setTimeout(() => {
+      this._updateAbsolute();
+      this._startInterval();
+    }, msToNextHour);
+  }
+
   private _clearInterval(): void {
     if (this._interval) {
       window.clearInterval(this._interval);
@@ -50,13 +76,13 @@ class HaAbsoluteTime extends ReactiveElement {
   private _startInterval(): void {
     this._clearInterval();
 
-    // update every 60 seconds
+    // update every hour
     this._interval = window.setInterval(() => {
       if (this._lastUpdate && isSameDay(this._lastUpdate, new Date())) {
         return;
       }
       this._updateAbsolute();
-    }, 60000);
+    }, ONE_HOUR);
   }
 
   private _updateAbsolute(): void {