Fable clean up

src/lib/site.ts

@@ -3,6 +3,12 @@ import { getCollection } from 'astro:content';
 import { getImage } from 'astro:assets';
 import type { ImageMetadata } from 'astro';
 
+// Theme background colors, the single source of truth for the
+// <meta name="theme-color"> tags and the FOUC-prevention scripts (injected in
+// Base.astro and Header.astro). Keep --color-bg in global.css in sync; CSS
+// cannot import these values.
+export const THEME_BG = { light: '#fbfaf7', dark: '#201f1d' };
+
 export const site = {
   brand: 'schmelczer.dev',
   name: 'Andras Schmelczer',
@@ -54,6 +60,17 @@ export function yearOf(date: Date) {
   return new Intl.DateTimeFormat('en', { year: 'numeric' }).format(date);
 }
 
+export function isExternal(url: string) {
+  return /^https?:\/\//.test(url);
+}
+
+// Directory-style paths get a trailing slash; the root and file-style paths
+// (e.g. /rss.xml) pass through unchanged. Shared by canonical URL generation
+// and the header's current-page matching so the two can never disagree.
+export function normalizeTrailingSlash(path: string) {
+  return path === '/' || path.endsWith('/') || /\.[^/]+$/.test(path) ? path : `${path}/`;
+}
+
 export function entrySlug(entry: { id: string }) {
   return entry.id.replace(/\.mdx?$/, '').replace(/\/index$/, '');
 }
@@ -268,6 +285,15 @@ export function buildBreadcrumbTrail({
   return trail;
 }
 
+// Adapts a trail for the visible Breadcrumbs component, which renders the
+// current page (the last crumb) as plain text rather than a link.
+export function visibleBreadcrumbs(trail: BreadcrumbCrumb[]) {
+  return trail.map((crumb, index) => ({
+    label: crumb.name,
+    href: index === trail.length - 1 ? undefined : crumb.href,
+  }));
+}
+
 // Builds the schema.org BreadcrumbList JSON-LD object for a given trail.
 // Shared by every page that emits breadcrumb structured data.
 export function buildBreadcrumbJsonLd(trail: BreadcrumbCrumb[]) {