Add auto footer links

src/components/Footer.astro

@@ -1,8 +1,17 @@
 ---
 import SocialLinks from "@components/SocialLinks.astro";
 import { FOOTER_COLUMNS, TERMS, SOCIALS } from "@data/nav";
+import { buildLinkChecker } from "@utils/nav";
 import EPSLogo from "/public/theme/eps-logo.svg";
 
+const linkExists = await buildLinkChecker();
+
+// Filter footer columns to only show links that point to existing pages
+const activeFooterColumns = FOOTER_COLUMNS.map((col) => ({
+  ...col,
+  items: col.items.filter((item) => linkExists(item.url)),
+})).filter((col) => col.items.length > 0);
+
 const buildTimestamp = __TIMESTAMP__;
 const gitVersion = __GIT_VERSION__;
 ---
@@ -18,7 +27,7 @@ const gitVersion = __GIT_VERSION__;
     </div>
     <div class="footer-grid">
     {
-      FOOTER_COLUMNS.map((col) => (
+      activeFooterColumns.map((col) => (
         <div>
           <p class="footer-col-title">{col.title}</p>
           <ul class="footer-links">

src/components/Header.astro

@@ -4,45 +4,9 @@ import Search from "@components/Search.astro";
 import ThemeToggle from "@components/ThemeToggle.astro";
 
 import { NAV_MENUS, type NavMenu } from "@data/nav";
-import { getCollection } from "astro:content";
-import { readFileSync } from "fs";
-
-// Parse redirect paths from astro.config.mjs at build time
-const configText = readFileSync("astro.config.mjs", "utf-8");
-const redirectMatch = configText.match(/redirects:\s*{([^}]+)}/s);
-const redirectPathsFromConfig: string[] = redirectMatch
-  ? [...redirectMatch[1].matchAll(/"([^"]+)"\s*:/g)].map((m) => m[1].replace(/^\//, "").replace(/\/$/, ""))
-  : [];
-
-// Build list of existing content page slugs to filter nav
-const existingPages = await getCollection("pages");
-const existingSlugs = new Set(existingPages.map((p) => p.id));
-
-// Standalone .astro pages that always exist regardless of content collection
-const alwaysExist = new Set([
-  "sessions", "speakers", "schedule", "posters", "talks", "tutorials",
-  "sprints", "jobs", "sponsors", "community-partners", "media-partners",
-]);
-
-function linkExists(url: string): boolean {
-  if (url.startsWith("http")) return true;
-  const slug = url.replace(/^\//, "").replace(/\/$/, "");
-  if (!slug) return true;
-  if (alwaysExist.has(slug)) return true;
-  const redirectPaths = [...new Set(redirectPathsFromConfig)];
-  if (redirectPaths.includes(slug)) return true;
-  // Check exact match in content pages
-  if (existingSlugs.has(slug)) return true;
-  // Check if slug is the short form of a nested page (e.g. "mentorship" from "programme/mentorship")
-  for (const existing of existingSlugs) {
-    if (existing.endsWith("/" + slug) || existing === slug) return true;
-  }
-  return false;
-}
+import { buildLinkChecker } from "@utils/nav";
 
-function sectionHasItems(section: { items: { url: string }[] }): boolean {
-  return section.items.some((item) => linkExists(item.url));
-}
+const linkExists = await buildLinkChecker();
 
 // Filter nav menus to only show links that point to existing pages
 const activeMenus = NAV_MENUS.map((menu) => ({

src/utils/nav.ts

@@ -0,0 +1,56 @@
+import { getCollection } from "astro:content";
+import { readFileSync } from "fs";
+
+/** Standalone .astro pages that always exist regardless of content collection */
+const ALWAYS_EXIST = new Set([
+  "sessions",
+  "speakers",
+  "schedule",
+  "posters",
+  "talks",
+  "tutorials",
+  "sprints",
+  "jobs",
+  "sponsors",
+  "community-partners",
+  "media-partners",
+]);
+
+/**
+ * Build a link-checker function that returns `true` for URLs pointing to
+ * existing pages (content collection, standalone pages, or redirect targets).
+ *
+ * Call once in `.astro` frontmatter, then pass the returned function to
+ * any filter step.
+ */
+export async function buildLinkChecker(): Promise<(url: string) => boolean> {
+  // Parse redirect paths from astro.config.mjs at build time
+  const configText = readFileSync("astro.config.mjs", "utf-8");
+  const redirectMatch = configText.match(/redirects:\s*{([^}]+)}/s);
+  const redirectPathsFromConfig: string[] = redirectMatch
+    ? [...redirectMatch[1].matchAll(/"([^"]+)"\s*:/g)].map((m) =>
+        m[1].replace(/^\//, "").replace(/\/$/, "")
+      )
+    : [];
+
+  // Build list of existing content page slugs
+  const existingPages = await getCollection("pages");
+  const existingSlugs = new Set(existingPages.map((p) => p.id));
+
+  const redirectPaths = [...new Set(redirectPathsFromConfig)];
+
+  return function linkExists(url: string): boolean {
+    if (url.startsWith("http")) return true;
+    const slug = url.replace(/^\//, "").replace(/\/$/, "");
+    if (!slug) return true;
+    if (ALWAYS_EXIST.has(slug)) return true;
+    if (redirectPaths.includes(slug)) return true;
+    // Check exact match in content pages
+    if (existingSlugs.has(slug)) return true;
+    // Check if slug is the short form of a nested page (e.g. "mentorship" from "programme/mentorship")
+    for (const existing of existingSlugs) {
+      if (existing.endsWith("/" + slug) || existing === slug) return true;
+    }
+    return false;
+  };
+}