Support full QWord heading hierarchy in DOCX

src/io/wordOffice.ts

@@ -39,8 +39,10 @@ export interface WordParagraphIndent {
   hanging?: number;
 }
 
+export type WordHeadingLevel = 1 | 2 | 3 | 4 | 5 | 6;
+
 export type WordBlock =
-  | { type: "heading"; level: 1 | 2 | 3; text: string; runs: WordInlineRun[]; alignment?: WordParagraphAlignment; indent?: WordParagraphIndent; bookmark?: string }
+  | { type: "heading"; level: WordHeadingLevel; text: string; runs: WordInlineRun[]; alignment?: WordParagraphAlignment; indent?: WordParagraphIndent; bookmark?: string }
   | { type: "paragraph"; text: string; runs: WordInlineRun[]; alignment?: WordParagraphAlignment; indent?: WordParagraphIndent; bookmark?: string }
   | { type: "list"; ordered: boolean; items: WordListItem[] }
   | { type: "table"; rows: string[][] }
@@ -111,7 +113,10 @@ const mammothStyleMap = [
   "p[style-name='Title'] => h1:fresh",
   "p[style-name='Heading 1'] => h1:fresh",
   "p[style-name='Heading 2'] => h2:fresh",
-  "p[style-name='Heading 3'] => h3:fresh"
+  "p[style-name='Heading 3'] => h3:fresh",
+  "p[style-name='Heading 4'] => h4:fresh",
+  "p[style-name='Heading 5'] => h5:fresh",
+  "p[style-name='Heading 6'] => h6:fresh"
 ];
 const xmlParserOptions = {
   ignoreAttributes: false,
@@ -239,7 +244,7 @@ export function htmlToWordBlocks(html: string): WordBlock[] {
       return;
     }
 
-    if (tagName === "h1" || tagName === "h2" || tagName === "h3") {
+    if (isHeadingTagName(tagName)) {
       const runs = elementInlineRuns(node);
       const text = inlineRunsText(runs);
       const alignment = paragraphAlignmentFromElement(node);
@@ -382,20 +387,17 @@ export function wordInlineRunsToTextRunOptions(runs: WordInlineRun[]) {
   return runs.map(wordInlineRunToTextRunOption);
 }
 
-function headingLevelFromTagName(tagName: string): 1 | 2 | 3 {
-  if (tagName === "h3") {
-    return 3;
-  }
-
-  return tagName === "h2" ? 2 : 1;
+function isHeadingTagName(tagName: string): tagName is `h${WordHeadingLevel}` {
+  return /^h[1-6]$/.test(tagName);
 }
 
-function docxHeadingLevel(level: 1 | 2 | 3, docx: DocxModule) {
-  if (level === 3) {
-    return docx.HeadingLevel.HEADING_3 ?? docx.HeadingLevel.HEADING_2;
-  }
+function headingLevelFromTagName(tagName: `h${WordHeadingLevel}`): WordHeadingLevel {
+  return Number.parseInt(tagName.slice(1), 10) as WordHeadingLevel;
+}
 
-  return level === 1 ? docx.HeadingLevel.HEADING_1 : docx.HeadingLevel.HEADING_2;
+function docxHeadingLevel(level: WordHeadingLevel, docx: DocxModule) {
+  const headingKey = `HEADING_${level}`;
+  return docx.HeadingLevel[headingKey] ?? docx.HeadingLevel.HEADING_2;
 }
 
 function wordInlineRunToTextRunOption(run: WordInlineRun) {
@@ -1025,6 +1027,15 @@ function docxParagraphTagName(properties: XmlRecord) {
   if (["heading3", "heading 3"].includes(styleValue)) {
     return "h3";
   }
+  if (["heading4", "heading 4"].includes(styleValue)) {
+    return "h4";
+  }
+  if (["heading5", "heading 5"].includes(styleValue)) {
+    return "h5";
+  }
+  if (["heading6", "heading 6"].includes(styleValue)) {
+    return "h6";
+  }
 
   return "p";
 }