scrabble-game/ui/src/components/Header.svelte

<script lang="ts">
  import { navigate } from '../lib/router.svelte';
  import { insideTelegram } from '../lib/telegram';
  import { connection } from '../lib/connection.svelte';
  import { t } from '../lib/i18n/index.svelte';
  import { app } from '../lib/app.svelte';
  import Spinner from './Spinner.svelte';
  import AdBanner from './AdBanner.svelte';

  let { title, back, grow = false }: { title: string; back?: string; grow?: boolean } = $props();

  // Inside Telegram the native header back button (App.svelte) is the back control, so
  // the app's own chevron is hidden to avoid two back affordances.
  const showBack = $derived(!!back && !insideTelegram());
</script>

<header class="nav" class:grow>
  <div class="bar">
    {#if showBack}
      <button class="icon back" onclick={() => back && navigate(back)} aria-label="Back">
        <span class="chev"></span>
      </button>
    {:else}
      <span class="spacer"></span>
    {/if}
    {#if connection.online}
      <h1>{title}</h1>
    {:else}
      <h1 class="connecting"><Spinner /> <span>{t('connection.connecting')}</span></h1>
    {/if}
    <!-- A right-hand spacer balances the back button so the title stays centred. -->
    <span class="spacer"></span>
  </div>
  <!-- The ad banner lives inside the nav, directly under the title bar, so it sits in the
       same place on every screen — and in the game (grown nav) the spare height falls below
       it (banner under the title, board pinned to the bottom). -->
  {#if app.profile?.banner && app.profile.banner.campaigns.length}
    <AdBanner
      campaigns={app.profile.banner.campaigns}
      timings={app.profile.banner.timings}
      reduceMotion={app.reduceMotion}
    />
  {/if}
</header>

<style>
  /* By default the nav bar is minimal and the content fills the screen. In the game
     it grows (class `grow`) to push the board and controls to the bottom. */
  .nav {
    flex: 0 0 auto;
    min-height: 52px;
    background: var(--bg-elev);
    border-bottom: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    user-select: none;
    -webkit-user-select: none;
  }
  .nav.grow {
    /* Grow into spare height (banner under the title, the board pinned to the bottom), but
       never shrink: on a short viewport the banner keeps its height and the board's own
       scroll (.stage) absorbs the squeeze, instead of the banner and the board splitting it. */
    flex: 1 0 auto;
  }
  .bar {
    display: flex;
    align-items: center;
    gap: var(--gap);
    padding: 10px var(--pad);
  }
  h1 {
    font-size: 1.05rem;
    margin: 0;
    flex: 1;
    text-align: center;
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }
  /* The "Connecting…" indicator replaces the title while offline: a spinner + muted label,
     centred like the title so the bar does not shift. */
  h1.connecting {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    color: var(--text-muted);
    font-weight: 500;
  }
  .icon,
  .spacer {
    min-width: 40px;
    height: 36px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }
  .back {
    background: none;
    border: none;
    color: var(--text);
    border-radius: var(--radius-sm);
    padding: 0 8px;
  }
  .back:hover {
    background: var(--surface-2);
  }
  /* A thin, compact "<" drawn from two borders — lighter than a glyph. */
  .chev {
    width: 11px;
    height: 11px;
    border-left: 2.5px solid currentColor;
    border-bottom: 2.5px solid currentColor;
    transform: rotate(45deg);
    margin-left: 3px;
  }
  /* Telegram fullscreen: TG's native nav occupies the band between the device notch
     (--tg-safe-top) and --tg-content-top. Our header spans that full band (so the layout below
     is unchanged) and centres the title within it, BELOW the notch — lining it up vertically
     with Telegram's own back/menu controls, which sit in the band's corners. */
  :global(html.tg-fullscreen) .bar {
    /* The bar is sized by its content + padding — in Telegram the title is the only child (the
       back chevron is hidden), so min-height (the nav-band height) doesn't bind. Without the
       (removed) hamburger that content shrank and the bar sat flush under Telegram's native nav
       band. So **padding-top** is the lever: it drops the title clear of the band — the notch
       plus a **10px** gap (was 6). A fixed px (not rem/em) gap so the clearance from Telegram's
       native controls stays constant if the user scales up the font (the title then grows
       downward and the bar with it). (Owner-tunable: the 10px.) */
    min-height: var(--tg-content-top);
    box-sizing: border-box;
    align-items: center;
    justify-content: center;
    padding-top: calc(var(--tg-safe-top) + 16px);
    padding-bottom: 6px;
  }
  :global(html.tg-fullscreen) .spacer {
    display: none;
  }
  :global(html.tg-fullscreen) h1 {
    flex: 0 1 auto;
  }
</style>