chore: rewrite DocLink's logic

Author: Sudrut

src/components/DocLink.astro

@@ -1,16 +1,15 @@
 ---
-import { getLinkToKey } from "../lib/doc-index";
+import { isLinkMissing, normalizeLink } from "../lib/doc-link";
 
 interface Props {
   src: string;
   section?: string;
 }
 
 const { src, section } = Astro.props;
-const rawLink = await getLinkToKey(src);
 
-const missing = rawLink === undefined;
-const link = rawLink ? rawLink + (section ? "#" + section : "") : "";
+const missing = await isLinkMissing(src);
+const link = normalizeLink(src) + (section ? "#" + section : "");
 ---
 
 {

src/lib/doc-link.ts

@@ -0,0 +1,27 @@
+import { getEntry } from "astro:content";
+
+function getIdFromLink(link: string): string {
+  if (link.startsWith("/")) {
+    link = link.slice(1);
+  }
+  if (link.endsWith("/")) {
+    link = link.slice(0, -1);
+  }
+  return link;
+}
+
+export function normalizeLink(link: string): string {
+  if (!link.startsWith("/")) {
+    link = "/" + link;
+  }
+  if (!link.endsWith("/")) {
+    link = link + "/";
+  }
+  return link;
+}
+
+export async function isLinkMissing(link: string): Promise<boolean> {
+  const id = getIdFromLink(link);
+  const entry = await getEntry("docs", id);
+  return entry === undefined;
+}