guide page versioning

src/config/io/guides.ts

@@ -0,0 +1,35 @@
+import { type CollectionEntry, getCollection } from "astro:content";
+import { getVersionsData } from "@config/io/generateTypeData";
+
+// load latest version of each page for version
+async function buildGuideCollection(version: string): Promise<CollectionEntry<'guide'>[]> {
+  const { versions } = await getVersionsData();
+  const guidePages = await getCollection("guide");
+
+  const pages: { [key: string]: CollectionEntry<'guide'> } = {};
+
+  for (const currentVersion of versions.toReversed()) {
+    for (const page of guidePages) {
+      let [guideVersion, id] = page.id.split('/');
+      guideVersion = guideVersion.replaceAll('_', '.');
+      id = id ?? "index";
+      if (guideVersion !== currentVersion.name) continue;
+
+      pages[id] = { ...page, id };
+    }
+
+    if (currentVersion.name === version) break;
+  }
+
+  return Object.values(pages);
+}
+
+let guideCollections: { [key: string]: Promise<CollectionEntry<'guide'>[]> } = {};
+
+export async function getGuideCollection(version: string): Promise<CollectionEntry<'guide'>[]> {
+  if (!(version in guideCollections)) {
+    guideCollections[version] = buildGuideCollection(version);
+  }
+
+  return guideCollections[version];
+}