Introduce calendar trigger description (#22814)

src/common/datetime/format_duration.ts

@@ -1,5 +1,6 @@
 import type { HaDurationData } from "../../components/ha-duration-input";
 import type { FrontendLocaleData } from "../../data/translation";
+import { formatListWithAnds } from "../string/format-list";
 
 const leftPad = (num: number) => (num < 10 ? `0${num}` : num);
 
@@ -42,3 +43,62 @@ export const formatDuration = (
   }
   return null;
 };
+
+export const formatDurationLong = (
+  locale: FrontendLocaleData,
+  duration: HaDurationData
+) => {
+  const d = duration.days || 0;
+  const h = duration.hours || 0;
+  const m = duration.minutes || 0;
+  const s = duration.seconds || 0;
+  const ms = duration.milliseconds || 0;
+
+  const parts: string[] = [];
+  if (d > 0) {
+    parts.push(
+      Intl.NumberFormat(locale.language, {
+        style: "unit",
+        unit: "day",
+        unitDisplay: "long",
+      }).format(d)
+    );
+  }
+  if (h > 0) {
+    parts.push(
+      Intl.NumberFormat(locale.language, {
+        style: "unit",
+        unit: "hour",
+        unitDisplay: "long",
+      }).format(h)
+    );
+  }
+  if (m > 0) {
+    parts.push(
+      Intl.NumberFormat(locale.language, {
+        style: "unit",
+        unit: "minute",
+        unitDisplay: "long",
+      }).format(m)
+    );
+  }
+  if (s > 0) {
+    parts.push(
+      Intl.NumberFormat(locale.language, {
+        style: "unit",
+        unit: "second",
+        unitDisplay: "long",
+      }).format(s)
+    );
+  }
+  if (ms > 0) {
+    parts.push(
+      Intl.NumberFormat(locale.language, {
+        style: "unit",
+        unit: "millisecond",
+        unitDisplay: "long",
+      }).format(ms)
+    );
+  }
+  return formatListWithAnds(locale, parts);
+};

src/data/automation_i18n.ts

@@ -1,6 +1,9 @@
 import type { HassConfig } from "home-assistant-js-websocket";
 import { ensureArray } from "../common/array/ensure-array";
-import { formatDuration } from "../common/datetime/format_duration";
+import {
+  formatDuration,
+  formatDurationLong,
+} from "../common/datetime/format_duration";
 import {
   formatTime,
   formatTimeWithSeconds,
@@ -720,6 +723,38 @@ const tryDescribeTrigger = (
     }`;
   }
 
+  // Calendar Trigger
+  if (trigger.trigger === "calendar") {
+    const calendarEntity = hass.states[trigger.entity_id]
+      ? computeStateName(hass.states[trigger.entity_id])
+      : trigger.entity_id;
+
+    let offsetChoice = trigger.offset.startsWith("-") ? "before" : "after";
+    let offset: string | string[] = trigger.offset.startsWith("-")
+      ? trigger.offset.substring(1).split(":")
+      : trigger.offset.split(":");
+    const duration = {
+      hours: offset.length > 0 ? +offset[0] : 0,
+      minutes: offset.length > 1 ? +offset[1] : 0,
+      seconds: offset.length > 2 ? +offset[2] : 0,
+    };
+    offset = formatDurationLong(hass.locale, duration);
+    if (offset === "") {
+      offsetChoice = "other";
+    }
+
+    return hass.localize(
+      `${triggerTranslationBaseKey}.calendar.description.full`,
+      {
+        eventChoice: trigger.event,
+        offsetChoice: offsetChoice,
+        offset: offset,
+        hasCalendar: trigger.entity_id ? "true" : "false",
+        calendar: calendarEntity,
+      }
+    );
+  }
+
   return (
     hass.localize(
       `ui.panel.config.automation.editor.triggers.type.${trigger.trigger}.label`

src/translations/en.json

@@ -2995,7 +2995,8 @@
                   "before": "Before",
                   "after": "After",
                   "description": {
-                    "picker": "When a calendar event starts or ends."
+                    "picker": "When a calendar event starts or ends.",
+                    "full": "When{offsetChoice, select, \n before { it's {offset} before}\n after { it's {offset} after}\n other {}\n} a calendar event{eventChoice, select, \n start { starts}\n end { ends}\n other { starts or ends}\n}{hasCalendar, select, \n true { in {calendar}}\n other {}\n}"
                   }
                 },
                 "device": {