Fix time and date-time 12h formats (#16692) (#16805)

* Fix time and date-time 12h formats  (#16692)

- am/pm check possible for other languages
- adjusted date format gallery page for consistency
- added gallery pages for date-time and time formats

* Fix typo in am/pm check (#16692)

gallery/src/data/date-options.ts

@@ -0,0 +1,24 @@
+import type { ControlSelectOption } from "../../../src/components/ha-control-select";
+
+export const timeOptions: ControlSelectOption[] = [
+  {
+    value: "now",
+    label: "Now",
+  },
+  {
+    value: "00:15:30",
+    label: "12:15:30 AM",
+  },
+  {
+    value: "06:15:30",
+    label: "06:15:30 AM",
+  },
+  {
+    value: "12:15:30",
+    label: "12:15:30 PM",
+  },
+  {
+    value: "18:15:30",
+    label: "06:15:30 PM",
+  },
+];

gallery/src/pages/date-time/date-time-numeric.markdown

@@ -0,0 +1,7 @@
+---
+title: Date-Time Format (Numeric)
+---
+
+This pages lists all supported languages with their available date-time formats.
+
+Formatting function: `const formatDateTimeNumeric: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/date-time-numeric.ts

@@ -0,0 +1,136 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import "../../../../src/components/ha-control-select";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatDateTimeNumeric } from "../../../../src/common/datetime/format_date_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-date-time-numeric")
+export class DemoDateTimeDateTimeNumeric extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatDateTimeNumeric(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatDateTimeNumeric(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatDateTimeNumeric(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 900px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-date-time-numeric": DemoDateTimeDateTimeNumeric;
+  }
+}

gallery/src/pages/date-time/date-time-seconds.markdown

@@ -0,0 +1,7 @@
+---
+title: Date-Time Format (Seconds)
+---
+
+This pages lists all supported languages with their available date-time formats.
+
+Formatting function: `const formatDateTimeWithSeconds: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/date-time-seconds.ts

@@ -0,0 +1,136 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import "../../../../src/components/ha-control-select";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatDateTimeWithSeconds } from "../../../../src/common/datetime/format_date_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-date-time-seconds")
+export class DemoDateTimeDateTimeSeconds extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatDateTimeWithSeconds(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatDateTimeWithSeconds(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatDateTimeWithSeconds(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 900px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-date-time-seconds": DemoDateTimeDateTimeSeconds;
+  }
+}

gallery/src/pages/date-time/date-time-short-year.markdown

@@ -0,0 +1,7 @@
+---
+title: Date-Time Format (Short w/ Year)
+---
+
+This pages lists all supported languages with their available date-time formats.
+
+Formatting function: `const formatShortDateTimeWithYear: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/date-time-short-year.ts

@@ -0,0 +1,136 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import "../../../../src/components/ha-control-select";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatShortDateTimeWithYear } from "../../../../src/common/datetime/format_date_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-date-time-short-year")
+export class DemoDateTimeDateTimeShortYear extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatShortDateTimeWithYear(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatShortDateTimeWithYear(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatShortDateTimeWithYear(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 900px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-date-time-short-year": DemoDateTimeDateTimeShortYear;
+  }
+}

gallery/src/pages/date-time/date-time-short.markdown

@@ -0,0 +1,7 @@
+---
+title: Date-Time Format (Short)
+---
+
+This pages lists all supported languages with their available date-time formats.
+
+Formatting function: `const formatShortDateTime: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/date-time-short.ts

@@ -0,0 +1,136 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import "../../../../src/components/ha-control-select";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatShortDateTime } from "../../../../src/common/datetime/format_date_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-date-time-short")
+export class DemoDateTimeDateTimeShort extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatShortDateTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatShortDateTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatShortDateTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 900px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-date-time-short": DemoDateTimeDateTimeShort;
+  }
+}

gallery/src/pages/date-time/date-time.markdown

@@ -0,0 +1,7 @@
+---
+title: Date-Time Format
+---
+
+This pages lists all supported languages with their available date-time formats.
+
+Formatting function: `const formatDateTime: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/date-time.ts

@@ -0,0 +1,136 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import "../../../../src/components/ha-control-select";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatDateTime } from "../../../../src/common/datetime/format_date_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-date-time")
+export class DemoDateTimeDateTime extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatDateTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatDateTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatDateTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 900px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-date-time": DemoDateTimeDateTime;
+  }
+}

gallery/src/pages/date-time/date.markdown

@@ -1,5 +1,5 @@
 ---
-title: (Numeric) Date Formatting
+title: Date Format (Numeric)
 ---
 
 This pages lists all supported languages with their available (numeric) date formats.

gallery/src/pages/date-time/time-seconds.markdown

@@ -0,0 +1,7 @@
+---
+title: Time Format (Seconds)
+---
+
+This pages lists all supported languages with their available time formats.
+
+Formatting function: `const formatTimeWithSeconds: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/time-seconds.ts

@@ -0,0 +1,135 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatTimeWithSeconds } from "../../../../src/common/datetime/format_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-time-seconds")
+export class DemoDateTimeTimeSeconds extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatTimeWithSeconds(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatTimeWithSeconds(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatTimeWithSeconds(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 600px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-time-seconds": DemoDateTimeTimeSeconds;
+  }
+}

gallery/src/pages/date-time/time-weekday.markdown

@@ -0,0 +1,7 @@
+---
+title: Time Format (Weekday)
+---
+
+This pages lists all supported languages with their available time formats.
+
+Formatting function: `const formatTimeWeekday: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/time-weekday.ts

@@ -0,0 +1,135 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatTimeWeekday } from "../../../../src/common/datetime/format_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-time-weekday")
+export class DemoDateTimeTimeWeekday extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatTimeWeekday(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatTimeWeekday(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatTimeWeekday(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 800px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-time-weekday": DemoDateTimeTimeWeekday;
+  }
+}

gallery/src/pages/date-time/time.markdown

@@ -0,0 +1,7 @@
+---
+title: Time Format
+---
+
+This pages lists all supported languages with their available time formats.
+
+Formatting function: `const formatTime: (dateObj: Date, locale: FrontendLocaleData) => string`

gallery/src/pages/date-time/time.ts

@@ -0,0 +1,136 @@
+import { html, css, LitElement } from "lit";
+import { customElement, state } from "lit/decorators";
+import "../../../../src/components/ha-card";
+import "../../../../src/components/ha-control-select";
+import { translationMetadata } from "../../../../src/resources/translations-metadata";
+import { formatTime } from "../../../../src/common/datetime/format_time";
+import { timeOptions } from "../../data/date-options";
+import { demoConfig } from "../../../../src/fake_data/demo_config";
+import {
+  FrontendLocaleData,
+  NumberFormat,
+  TimeFormat,
+  DateFormat,
+  FirstWeekday,
+  TimeZone,
+} from "../../../../src/data/translation";
+
+@customElement("demo-date-time-time")
+export class DemoDateTimeTime extends LitElement {
+  @state() private selection?: string = "now";
+
+  @state() private date: Date = new Date();
+
+  handleValueChanged(e: CustomEvent) {
+    this.selection = e.detail.value as string;
+    this.date = new Date();
+    if (this.selection !== "now") {
+      const [hours, minutes, seconds] = this.selection.split(":").map(Number);
+      this.date.setHours(hours);
+      this.date.setMinutes(minutes);
+      this.date.setSeconds(seconds);
+    }
+  }
+
+  protected render() {
+    const defaultLocale: FrontendLocaleData = {
+      language: "en",
+      number_format: NumberFormat.language,
+      time_format: TimeFormat.language,
+      date_format: DateFormat.language,
+      first_weekday: FirstWeekday.language,
+      time_zone: TimeZone.local,
+    };
+    return html`
+      <ha-control-select
+        .value=${this.selection}
+        .options=${timeOptions}
+        @value-changed=${this.handleValueChanged}
+      >
+      </ha-control-select>
+      <mwc-list>
+        <div class="container header">
+          <div>Language</div>
+          <div class="center">Default (lang)</div>
+          <div class="center">12 Hours</div>
+          <div class="center">24 Hours</div>
+        </div>
+        ${Object.entries(translationMetadata.translations)
+          .filter(([key, _]) => key !== "test")
+          .map(
+            ([key, value]) => html`
+              <div class="container">
+                <div>${value.nativeName}</div>
+                <div class="center">
+                  ${formatTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.language,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.am_pm,
+                    },
+                    demoConfig
+                  )}
+                </div>
+                <div class="center">
+                  ${formatTime(
+                    this.date,
+                    {
+                      ...defaultLocale,
+                      language: key,
+                      time_format: TimeFormat.twenty_four,
+                    },
+                    demoConfig
+                  )}
+                </div>
+              </div>
+            `
+          )}
+      </mwc-list>
+    `;
+  }
+
+  static get styles() {
+    return css`
+      ha-control-select {
+        max-width: 800px;
+        margin: 12px auto;
+      }
+      .header {
+        font-weight: bold;
+      }
+      .center {
+        text-align: center;
+      }
+      .container {
+        max-width: 600px;
+        margin: 12px auto;
+        display: flex;
+        align-items: center;
+        justify-content: space-evenly;
+      }
+
+      .container > div {
+        flex-grow: 1;
+        width: 20%;
+      }
+    `;
+  }
+}
+
+declare global {
+  interface HTMLElementTagNameMap {
+    "demo-date-time-time": DemoDateTimeTime;
+  }
+}

src/common/datetime/format_date_time.ts

@@ -15,20 +15,15 @@ export const formatDateTime = (
 
 const formatDateTimeMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      year: "numeric",
-        ? "en-u-hc-h23"
+      month: "long",
-        : locale.language,
+      day: "numeric",
-      {
+      hour: useAmPm(locale) ? "numeric" : "2-digit",
-        year: "numeric",
+      minute: "2-digit",
-        month: "long",
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-        day: "numeric",
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        hour: useAmPm(locale) ? "numeric" : "2-digit",
+    })
-        minute: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // Aug 9, 2021, 8:23 AM
@@ -40,20 +35,15 @@ export const formatShortDateTimeWithYear = (
 
 const formatShortDateTimeWithYearMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      year: "numeric",
-        ? "en-u-hc-h23"
+      month: "short",
-        : locale.language,
+      day: "numeric",
-      {
+      hour: useAmPm(locale) ? "numeric" : "2-digit",
-        year: "numeric",
+      minute: "2-digit",
-        month: "short",
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-        day: "numeric",
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        hour: useAmPm(locale) ? "numeric" : "2-digit",
+    })
-        minute: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // Aug 9, 8:23 AM
@@ -65,19 +55,14 @@ export const formatShortDateTime = (
 
 const formatShortDateTimeMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      month: "short",
-        ? "en-u-hc-h23"
+      day: "numeric",
-        : locale.language,
+      hour: useAmPm(locale) ? "numeric" : "2-digit",
-      {
+      minute: "2-digit",
-        month: "short",
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-        day: "numeric",
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        hour: useAmPm(locale) ? "numeric" : "2-digit",
+    })
-        minute: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // August 9, 2021, 8:23:15 AM
@@ -89,21 +74,16 @@ export const formatDateTimeWithSeconds = (
 
 const formatDateTimeWithSecondsMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      year: "numeric",
-        ? "en-u-hc-h23"
+      month: "long",
-        : locale.language,
+      day: "numeric",
-      {
+      hour: useAmPm(locale) ? "numeric" : "2-digit",
-        year: "numeric",
+      minute: "2-digit",
-        month: "long",
+      second: "2-digit",
-        day: "numeric",
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-        hour: useAmPm(locale) ? "numeric" : "2-digit",
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        minute: "2-digit",
+    })
-        second: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // 9/8/2021, 8:23 AM

src/common/datetime/format_time.ts

@@ -13,17 +13,12 @@ export const formatTime = (
 
 const formatTimeMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      hour: "numeric",
-        ? "en-u-hc-h23"
+      minute: "2-digit",
-        : locale.language,
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-      {
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        hour: "numeric",
+    })
-        minute: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // 9:15:24 PM || 21:15:24
@@ -35,18 +30,13 @@ export const formatTimeWithSeconds = (
 
 const formatTimeWithSecondsMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      hour: useAmPm(locale) ? "numeric" : "2-digit",
-        ? "en-u-hc-h23"
+      minute: "2-digit",
-        : locale.language,
+      second: "2-digit",
-      {
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-        hour: useAmPm(locale) ? "numeric" : "2-digit",
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        minute: "2-digit",
+    })
-        second: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // Tuesday 7:00 PM || Tuesday 19:00
@@ -58,18 +48,13 @@ export const formatTimeWeekday = (
 
 const formatTimeWeekdayMem = memoizeOne(
   (locale: FrontendLocaleData, serverTimeZone: string) =>
-    new Intl.DateTimeFormat(
+    new Intl.DateTimeFormat(locale.language, {
-      locale.language === "en" && !useAmPm(locale)
+      weekday: "long",
-        ? "en-u-hc-h23"
+      hour: useAmPm(locale) ? "numeric" : "2-digit",
-        : locale.language,
+      minute: "2-digit",
-      {
+      hourCycle: useAmPm(locale) ? "h12" : "h23",
-        weekday: "long",
+      timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-        hour: useAmPm(locale) ? "numeric" : "2-digit",
+    })
-        minute: "2-digit",
-        hour12: useAmPm(locale),
-        timeZone: locale.time_zone === "server" ? serverTimeZone : undefined,
-      }
-    )
 );
 
 // 21:15

src/common/datetime/use_am_pm.ts

@@ -8,8 +8,10 @@ export const useAmPm = memoizeOne((locale: FrontendLocaleData): boolean => {
   ) {
     const testLanguage =
       locale.time_format === TimeFormat.language ? locale.language : undefined;
-    const test = new Date().toLocaleString(testLanguage);
+    const test = new Date("January 1, 2023 22:00:00").toLocaleString(
-    return test.includes("AM") || test.includes("PM");
+      testLanguage
+    );
+    return test.includes("10");
   }
 
   return locale.time_format === TimeFormat.am_pm;