feat: add preview update channel

2 files changed, 151 insertions, 1 deletions

diff --git a/website/src/components/Header.astro b/website/src/components/Header.astro
new file mode 100644
index 00000000..982efd2e
--- /dev/null
+++ b/website/src/components/Header.astro
@@ -0,0 +1,149 @@
+---
+import config from 'virtual:starlight/user-config';
+
+import LanguageSelect from 'virtual:starlight/components/LanguageSelect';
+import Search from 'virtual:starlight/components/Search';
+import SiteTitle from 'virtual:starlight/components/SiteTitle';
+import SocialIcons from 'virtual:starlight/components/SocialIcons';
+import ThemeSelect from 'virtual:starlight/components/ThemeSelect';
+
+const shouldRenderSearch =
+  config.pagefind || config.components.Search !== '@astrojs/starlight/components/Search.astro';
+
+const pathname = Astro.url.pathname;
+const isDocs = pathname === '/docs/' || pathname.startsWith('/docs/');
+const isPreview = pathname === '/docs/preview/' || pathname.startsWith('/docs/preview/');
+const stableHref = isPreview ? pathname.replace(/^\/docs\/preview\/?/, '/docs/') : pathname;
+const previewHref = isPreview
+  ? pathname
+  : pathname === '/docs/'
+    ? '/docs/preview/'
+    : pathname.replace(/^\/docs\/?/, '/docs/preview/');
+---
+
+<div class="header">
+  <div class="title-wrapper sl-flex">
+    <SiteTitle />
+  </div>
+  <div class="sl-flex print:hidden search-wrapper">
+    {isDocs && (
+      <nav class="docs-channel-switcher" aria-label="Documentation channel">
+        <a href={stableHref} aria-current={!isPreview ? 'page' : undefined}>Stable</a>
+        <a href={previewHref} aria-current={isPreview ? 'page' : undefined}>Preview</a>
+      </nav>
+    )}
+    {shouldRenderSearch && <Search />}
+  </div>
+  <div class="sl-hidden md:sl-flex print:hidden right-group">
+    <div class="sl-flex social-icons">
+      <SocialIcons />
+    </div>
+    <ThemeSelect />
+    <LanguageSelect />
+  </div>
+</div>
+
+<style>
+  @layer starlight.core {
+    .header {
+      display: flex;
+      gap: var(--sl-nav-gap);
+      justify-content: space-between;
+      align-items: center;
+      height: 100%;
+    }
+
+    .title-wrapper {
+      overflow: clip;
+      padding: 0.25rem;
+      margin: -0.25rem;
+      min-width: 0;
+    }
+
+    .search-wrapper {
+      align-items: center;
+      gap: 0.75rem;
+      min-width: 0;
+    }
+
+    .docs-channel-switcher {
+      display: flex;
+      align-items: center;
+      border: 1px solid var(--sl-color-hairline);
+      border-radius: 4px;
+      overflow: hidden;
+      background: var(--sl-color-bg-nav);
+      font-size: var(--sl-text-xs);
+      font-weight: 700;
+      line-height: 1;
+      white-space: nowrap;
+    }
+
+    .docs-channel-switcher a {
+      color: var(--sl-color-gray-2);
+      text-decoration: none;
+      padding: 0.45rem 0.6rem;
+    }
+
+    .docs-channel-switcher a + a {
+      border-inline-start: 1px solid var(--sl-color-hairline);
+    }
+
+    .docs-channel-switcher a[aria-current="page"] {
+      color: var(--sl-color-accent-high);
+      background: color-mix(in srgb, var(--sl-color-accent) 14%, transparent);
+    }
+
+    .docs-channel-switcher a:hover {
+      color: var(--sl-color-accent-high);
+    }
+
+    .right-group,
+    .social-icons {
+      gap: 1rem;
+      align-items: center;
+    }
+
+    .social-icons::after {
+      content: "";
+      height: 2rem;
+      border-inline-end: 1px solid var(--sl-color-gray-5);
+    }
+
+    @media (max-width: 38rem) {
+      .docs-channel-switcher {
+        display: none;
+      }
+    }
+
+    @media (min-width: 50rem) {
+      :global(:root[data-has-sidebar]) {
+        --__sidebar-pad: calc(2 * var(--sl-nav-pad-x));
+      }
+
+      :global(:root:not([data-has-toc])) {
+        --__toc-width: 0rem;
+      }
+
+      .header {
+        --__sidebar-width: max(0rem, var(--sl-content-inline-start, 0rem) - var(--sl-nav-pad-x));
+        --__main-column-fr: calc(
+          (
+              100% + var(--__sidebar-pad, 0rem) - var(--__toc-width, var(--sl-sidebar-width)) -
+                (2 * var(--__toc-width, var(--sl-nav-pad-x))) - var(--sl-content-inline-start, 0rem) -
+                var(--sl-content-width)
+            ) / 2
+        );
+        display: grid;
+        grid-template-columns:
+          minmax(
+            calc(var(--__sidebar-width) + max(0rem, var(--__main-column-fr) - var(--sl-nav-gap))),
+            auto
+          )
+          1fr
+          auto;
+        align-content: center;
+      }
+    }
+  }
+</style>
diff --git a/website/src/content.config.ts b/website/src/content.config.ts
index c9a9b8fd..834d37cf 100644
--- a/website/src/content.config.ts
+++ b/website/src/content.config.ts
@@ -5,7 +5,8 @@ import { docsSchema } from '@astrojs/starlight/schema';
 
 function docsPath({ entry }: { entry: string }) {
   const slug = entry.replace(/\.(md|mdx|markdown|mdown|mkdn|mkd|mdwn)$/i, '');
-  return slug === 'index' ? 'docs' : `docs/${slug}`;
+  const normalized = slug.replace(/\/index$/, '');
+  return normalized === 'index' ? 'docs' : `docs/${normalized}`;
 }
 
 export const collections = {