✨feature: First push to git

src/output/excel.ts

@@ -0,0 +1,32 @@
+import { mkdir } from 'node:fs/promises';
+import { dirname } from 'node:path';
+import XLSX from 'xlsx';
+import { CatalogPayload, OutputWriter, sanitizeSheetName } from './sheets.js';
+
+export class ExcelWriter implements OutputWriter {
+  public constructor(private readonly path: string) {}
+
+  public async write(payload: CatalogPayload): Promise<void> {
+    const workbook = XLSX.utils.book_new();
+    const grouped = new Map<string, Record<string, unknown>[]>();
+    for (const row of payload.rows) {
+      const sheet = sanitizeSheetName(String(row['Source Newsletter'] ?? 'Newsletter'));
+      grouped.set(sheet, [...(grouped.get(sheet) ?? []), row]);
+    }
+    for (const [sheet, rows] of grouped) {
+      XLSX.utils.book_append_sheet(workbook, XLSX.utils.json_to_sheet(rows), sheet);
+    }
+    XLSX.utils.book_append_sheet(
+      workbook,
+      XLSX.utils.json_to_sheet(payload.sponsors),
+      'Sponsored Links'
+    );
+    XLSX.utils.book_append_sheet(
+      workbook,
+      XLSX.utils.json_to_sheet(payload.deadLinks),
+      'Dead Links'
+    );
+    await mkdir(dirname(this.path), { recursive: true });
+    XLSX.writeFile(workbook, this.path);
+  }
+}