Fix Preach My Gospel links and reference formats for 2023 edition

src/scriptures/books.ts

@@ -24,6 +24,15 @@ export interface ScriptureBook {
 	 * (e.g. `"chapter-"` turns chapter `1` into the path segment `chapter-1`).
 	 */
 	chapterPrefix?: string;
+	/**
+	 * Optional map from a normalized section key to the URL path segment
+	 * appended after `urlBase`. When present, the URL builder resolves the
+	 * chapter via this map instead of the default `chapterPrefix + chapter`
+	 * construction.  Keys use the canonical forms returned by
+	 * `normalizePmgSection` (e.g. `"message"`, `"intro"`, `"1"`, `"3.1"`,
+	 * `"3.2"`, …).
+	 */
+	chapterMap?: Record<string, string>;
 }
 
 export const SCRIPTURE_BOOKS: ScriptureBook[] = [
@@ -136,9 +145,29 @@ export const SCRIPTURE_BOOKS: ScriptureBook[] = [
 	{
 		names: ['Preach My Gospel', 'PMG'],
 		volume: 'manual',
-		slug: 'preach-my-gospel-a-guide-to-sharing-the-gospel-of-jesus-christ',
-		urlBase:
-			'https://www.churchofjesuschrist.org/study/manual/preach-my-gospel-a-guide-to-sharing-the-gospel-of-jesus-christ',
-		chapterPrefix: 'chapter-',
+		slug: 'preach-my-gospel-2023',
+		urlBase: 'https://www.churchofjesuschrist.org/study/manual/preach-my-gospel-2023',
+		chapterMap: {
+			'message': '01-first-presidency-message',
+			'intro':   '02-intro',
+			'1':       '03-chapter-1',
+			'2':       '04-chapter-2',
+			'3.1':     '04-chapter-3/06-chapter-3-intro',
+			'3.2':     '04-chapter-3/07-chapter-3-invite',
+			'3.3':     '04-chapter-3/08-chapter-3-lesson-1',
+			'3.4':     '04-chapter-3/09-chapter-3-lesson-2',
+			'3.5':     '04-chapter-3/10-chapter-3-lesson-3',
+			'3.6':     '04-chapter-3/11-chapter-3-lesson-4',
+			'4':       '12-chapter-4',
+			'5':       '13-chapter-5',
+			'6':       '14-chapter-6',
+			'7':       '15-chapter-7',
+			'8':       '16-chapter-8',
+			'9':       '17-chapter-9',
+			'10':      '18-chapter-10',
+			'11':      '19-chapter-11',
+			'12':      '20-chapter-12',
+			'13':      '21-chapter-13',
+		},
 	},
 ];

src/scriptures/parser.ts

@@ -59,13 +59,17 @@ export const SCRIPTURE_REGEX: RegExp = (() => {
 	// hyphen-separated additional digit groups (e.g. "1", "2-4", "9,11").
 	const versePart = String.raw`\d+(?:[-,]\d+)*`;
 
-	// After the book name, optionally allow "page N", "pg. N", or "#N"
-	// in addition to the bare "N" used by standard scripture references.
-	// This supports formats like "PMG page 18", "PMG pg. 18", "PMG #18".
-	const numberPrefix = String.raw`(?:(?:page|pg\.)\s+|#\s*)?`;
+	// Chapter / section identifier, tried in specificity order so that longer
+	// PMG-specific tokens are matched before the generic digit fallback:
+	//   • PMG named sections:  Message, Intro
+	//   • PMG lesson shorthand: L1–L4
+	//   • PMG chapter-3 letter: 3B  (= section 3.2, the "invite" page)
+	//   • PMG chapter-3 decimal: 3.1–3.6
+	//   • Any book: optional "chapter"/"ch."/"#" prefix followed by digits
+	const chapterPart = String.raw`Message|Intro|L[1-4]|3B|3\.[1-6]|(?:(?:chapter|ch\.)\s+|#\s*)?\d+`;
 
 	return new RegExp(
-		String.raw`\b(${bookAlt})\s+${numberPrefix}(\d+)(?::(${versePart}))?`,
+		String.raw`\b(${bookAlt})\s+(${chapterPart})(?::(${versePart}))?`,
 		'gi',
 	);
 })();

src/scriptures/urlBuilder.ts

@@ -23,10 +23,57 @@ function firstVerseAnchor(verseStr: string): string {
 	return m ? `p${m[0]}` : 'p1';
 }
 
+/**
+ * Normalise a raw PMG section string (as captured by the regex) into the
+ * canonical key used in `ScriptureBook.chapterMap`.
+ *
+ * Supported inputs (case-insensitive):
+ *   "Message"              → "message"
+ *   "Intro"                → "intro"
+ *   "L1"–"L4"             → "3.3"–"3.6"
+ *   "3B"                   → "3.2"
+ *   "3.1"–"3.6"           → "3.1"–"3.6"
+ *   "3" / "chapter 3" / "ch. 3" / "#3"  → "3.1"  (chapter-3 intro)
+ *   "1" / "chapter 1" / "ch. 1" / "#1"  → "1"
+ */
+export function normalizePmgSection(raw: string): string | undefined {
+	const s = raw.toLowerCase().trim();
+
+	if (s === 'message') return 'message';
+	if (s === 'intro') return 'intro';
+
+	// Lesson shorthand: L1–L4 map to chapter-3 sections 3.3–3.6.
+	// Offset 2 because: L1 → 1+2=3 → "3.3", L2 → 2+2=4 → "3.4", etc.
+	const lessonMatch = s.match(/^l([1-4])$/);
+	if (lessonMatch) return `3.${2 + parseInt(lessonMatch[1]!, 10)}`;
+
+	// Letter shorthand: 3B = section 3.2 (the "invite" page).
+	if (s === '3b') return '3.2';
+
+	// Decimal notation 3.1–3.6: pass through as-is.
+	const decimalMatch = s.match(/^3\.([1-6])$/);
+	if (decimalMatch) return `3.${decimalMatch[1]}`;
+
+	// Generic chapter reference (optional "chapter"/"ch."/"#" prefix + digits).
+	const chapterMatch = s.match(/^(?:(?:chapter|ch\.)\s+|#\s*)?(\d+)$/);
+	if (chapterMatch) {
+		const n = chapterMatch[1];
+		// Bare "3" (or "chapter 3" etc.) means the chapter-3 intro page.
+		return n === '3' ? '3.1' : n;
+	}
+
+	return undefined;
+}
+
 /**
  * Build a ChurchOfJesusChrist.org study URL for the given reference.
  *
- * Examples:
+ * When `book.chapterMap` is present (e.g. Preach My Gospel), the chapter
+ * string is normalised via `normalizePmgSection` and looked up in the map to
+ * produce the correct path segment.  Verse anchors are not applied for
+ * chapterMap books because PMG pages do not use paragraph-level anchors.
+ *
+ * Examples for standard scripture books:
  *   book=gen, chapter="9", verses=undefined
  *     → https://…/ot/gen/9?lang=eng
  *   book=gen, chapter="9", verses="1"
@@ -35,13 +82,33 @@ function firstVerseAnchor(verseStr: string): string {
  *     → https://…/ot/gen/9?lang=eng&id=p2-p4#p2
  *   book=matt, chapter="5", verses="9,11"
  *     → https://…/nt/matt/5?lang=eng&id=p9,p11#p9
+ *
+ * Examples for Preach My Gospel:
+ *   book=pmg, chapter="Message"
+ *     → https://…/preach-my-gospel-2023/01-first-presidency-message?lang=eng
+ *   book=pmg, chapter="3" (or "3.1")
+ *     → https://…/preach-my-gospel-2023/04-chapter-3/06-chapter-3-intro?lang=eng
+ *   book=pmg, chapter="L1" (or "3.3")
+ *     → https://…/preach-my-gospel-2023/04-chapter-3/08-chapter-3-lesson-1?lang=eng
  */
 export function buildUrl(
 	book: ScriptureBook,
 	chapter: string,
 	verses: string | undefined,
 ): string {
 	const base = book.urlBase ?? `${BASE_URL}/${book.volume}/${book.slug}`;
+
+	// Books with a chapterMap (e.g. PMG) use a lookup table for URL paths.
+	if (book.chapterMap) {
+		const key = normalizePmgSection(chapter);
+		const path = key !== undefined ? book.chapterMap[key] : undefined;
+		if (path) {
+			return `${base}/${path}?lang=eng`;
+		}
+		// Unrecognised section: fall back to a best-effort URL.
+		return `${base}/${chapter}?lang=eng`;
+	}
+
 	const chapterSegment = `${book.chapterPrefix ?? ''}${chapter}`;
 	const chapterUrl = `${base}/${chapterSegment}?lang=eng`;