text highlight and og image

lib/og.ts

@@ -0,0 +1,171 @@
+/**
+ * OG Image metadata utilities.
+ *
+ * Builds the /api/og URL with appropriate query params for dynamic
+ * Open Graph image generation. Used by page-level metadata exports.
+ */
+
+import { BOOK_NAMES, CC_LILAS } from "@/lib/constants";
+
+const SITE_URL =
+  process.env.NEXT_PUBLIC_SITE_URL || "https://prabhupadasays.org";
+
+// ---------------------------------------------------------------------------
+// Types
+// ---------------------------------------------------------------------------
+
+export type OgParams = {
+  title: string;
+  detail?: string;
+  quote?: string;
+};
+
+// ---------------------------------------------------------------------------
+// Build the /api/og image URL
+// ---------------------------------------------------------------------------
+
+/**
+ * Build a fully-qualified URL to the /api/og image endpoint.
+ *
+ * The URL is kept as short as possible — only non-empty params are included.
+ * The quote is truncated to 260 chars to keep URL length reasonable.
+ */
+export function buildOgImageUrl(params: OgParams): string {
+  const url = new URL("/api/og", SITE_URL);
+
+  url.searchParams.set("title", params.title);
+
+  if (params.detail) {
+    url.searchParams.set("detail", params.detail);
+  }
+
+  if (params.quote) {
+    const truncated =
+      params.quote.length > 260
+        ? params.quote.slice(0, 257) + "..."
+        : params.quote;
+    url.searchParams.set("quote", truncated);
+  }
+
+  return url.toString();
+}
+
+/**
+ * Build OG metadata object for use in Next.js page `metadata` exports.
+ *
+ * Returns the `openGraph` and `twitter` fields to spread into `Metadata`.
+ */
+export function buildOgMeta(params: OgParams & { description?: string }) {
+  const imageUrl = buildOgImageUrl(params);
+  const description =
+    params.description ||
+    params.quote ||
+    `${params.title}${params.detail ? ` — ${params.detail}` : ""}`;
+
+  return {
+    openGraph: {
+      title: params.title,
+      description,
+      images: [
+        {
+          url: imageUrl,
+          width: 1200,
+          height: 630,
+          alt: params.title,
+        },
+      ],
+      siteName: "Prabhupāda Says",
+    },
+    twitter: {
+      card: "summary_large_image" as const,
+      title: params.title,
+      description,
+      images: [imageUrl],
+    },
+  };
+}
+
+// ---------------------------------------------------------------------------
+// Helpers for common page types
+// ---------------------------------------------------------------------------
+
+/** OG metadata for a book page. */
+export function ogForBook(code: string) {
+  const title = BOOK_NAMES[code] || code.toUpperCase();
+  return buildOgMeta({ title });
+}
+
+/** OG metadata for a verse page. */
+export function ogForVerse(
+  code: string,
+  parts: { division?: string; chapter: number; verse: number },
+) {
+  const title = BOOK_NAMES[code] || code.toUpperCase();
+  let detail: string;
+
+  if (code === "sb" && parts.division) {
+    detail = `Canto ${parts.division}, Chapter ${parts.chapter}, Verse ${parts.verse}`;
+  } else if (code === "cc" && parts.division) {
+    const lila = CC_LILAS[parts.division] || parts.division;
+    detail = `${lila}, Chapter ${parts.chapter}, Verse ${parts.verse}`;
+  } else {
+    detail = `Chapter ${parts.chapter}, Verse ${parts.verse}`;
+  }
+
+  return buildOgMeta({ title, detail });
+}
+
+/** OG metadata for a prose chapter. */
+export function ogForChapter(code: string, chapterTitle: string) {
+  const bookTitle = BOOK_NAMES[code] || code.toUpperCase();
+  return buildOgMeta({ title: bookTitle, detail: chapterTitle });
+}
+
+/** OG metadata for an essay. */
+export function ogForEssay(title: string) {
+  return buildOgMeta({
+    title,
+    detail: "Essay by Śrīla Prabhupāda",
+  });
+}
+
+/** OG metadata for a letter. */
+export function ogForLetter(recipient: string, meta?: string) {
+  return buildOgMeta({
+    title: `Letter to ${recipient}`,
+    detail: meta || undefined,
+  });
+}
+
+/** OG metadata for a journal entry. */
+export function ogForJournal(journalTitle: string, entryTitle?: string) {
+  return buildOgMeta({
+    title: journalTitle,
+    detail: entryTitle || undefined,
+  });
+}
+
+/** OG metadata for a magazine issue. */
+export function ogForMagazine(magazineTitle: string, issueTitle?: string) {
+  return buildOgMeta({
+    title: magazineTitle,
+    detail: issueTitle || undefined,
+  });
+}
+
+/** OG metadata for an other document chapter. */
+export function ogForOtherDocument(docTitle: string, chapterTitle?: string) {
+  return buildOgMeta({
+    title: docTitle,
+    detail: chapterTitle || undefined,
+  });
+}
+
+/** Default OG metadata for the site. */
+export function ogDefault() {
+  return buildOgMeta({
+    title: "Prabhupāda Says",
+    description:
+      "Browse the books and teachings of His Divine Grace A.C. Bhaktivedanta Swami Prabhupāda",
+  });
+}