feat: Wabenhain Honig-Shop Anwendung

Vollstaendige Next.js/Prisma-E-Commerce-Anwendung fuer eine Imkerei:
Shop, Warenkorb, Stripe-Checkout, Kundenkonto mit 2FA, Admin-Bereich
(Produkte, Ernten, Chargen, Bestellungen, Gutscheine, admin-editierbare
Website-Inhalte), i18n (DE/EN), Rate-Limiting/CSP/Audit-Log-Haertung,
PostgreSQL- und MySQL-Unterstuetzung ueber austauschbare Prisma-
Treiber-Adapter, Unit-/Komponenten-/E2E-Tests.

src/lib/invoice-pdf.ts

@@ -0,0 +1,130 @@
+import PDFDocument from "pdfkit";
+import { formatPrice, formatDate } from "@/lib/format";
+import { getCompanyInfo } from "@/lib/company-info";
+import { getDictionary } from "@/i18n/get-dictionary";
+import type { Locale } from "@/i18n/config";
+
+interface InvoicePdfInput {
+  locale: Locale;
+  invoiceNumber: string;
+  issuedAt: Date;
+  totalCents: number;
+  order: {
+    orderNumber: string;
+    firstName: string;
+    lastName: string;
+    street: string;
+    zip: string;
+    city: string;
+    currency: string;
+    subtotalCents: number;
+    shippingCents: number;
+    discountCents: number;
+    discountCode?: { code: string } | null;
+    items: { productName: string; weightGrams: number; quantity: number; unitPriceCents: number; totalCents: number }[];
+  };
+}
+
+/**
+ * Erzeugt die Rechnung als PDF (pdfkit — reine JS-Bibliothek ohne
+ * Headless-Browser/native Abhaengigkeiten, haelt das Docker-Image schlank).
+ * Wird on-the-fly beim Download erzeugt statt dauerhaft gespeichert. Nutzt
+ * dieselben Uebersetzungen wie die HTML-Rechnungsansicht (t.invoicePage),
+ * damit beide Darstellungen derselben Rechnung konsistent bleiben.
+ */
+export async function generateInvoicePdf(input: InvoicePdfInput): Promise<Buffer> {
+  const t = getDictionary(input.locale).invoicePage;
+  const company = await getCompanyInfo();
+  const doc = new PDFDocument({ margin: 50, size: "A4" });
+  const chunks: Buffer[] = [];
+  doc.on("data", (chunk: Buffer) => chunks.push(chunk));
+  const done = new Promise<Buffer>((resolve, reject) => {
+    doc.on("end", () => resolve(Buffer.concat(chunks)));
+    doc.on("error", reject);
+  });
+
+  doc.fontSize(20).fillColor("#24352B").text(company.name.toUpperCase(), { continued: false });
+  doc
+    .fontSize(9)
+    .fillColor("#666666")
+    .text(`${company.address.street}, ${company.address.zip} ${company.address.city}`);
+
+  doc.moveDown(1.5);
+  doc.fontSize(14).fillColor("#24352B").text(t.invoiceLabel(input.invoiceNumber));
+  doc
+    .fontSize(9)
+    .fillColor("#666666")
+    .text(t.orderLabel(input.order.orderNumber))
+    .text(`${t.dateLabel} ${formatDate(input.issuedAt)}`);
+
+  doc.moveDown(1);
+  doc
+    .fontSize(10)
+    .fillColor("#242424")
+    .text(`${input.order.firstName} ${input.order.lastName}`)
+    .text(input.order.street)
+    .text(`${input.order.zip} ${input.order.city}`);
+
+  doc.moveDown(1.5);
+
+  const tableTop = doc.y;
+  const columns = { name: 50, qty: 320, price: 380, total: 470 };
+  doc
+    .fontSize(9)
+    .fillColor("#666666")
+    .text(t.itemHeader, columns.name, tableTop)
+    .text(t.quantityHeader, columns.qty, tableTop)
+    .text(t.priceHeader, columns.price, tableTop)
+    .text(t.totalHeader, columns.total, tableTop);
+  doc
+    .moveTo(50, tableTop + 14)
+    .lineTo(545, tableTop + 14)
+    .strokeColor("#dddddd")
+    .stroke();
+
+  let y = tableTop + 22;
+  doc.fontSize(10).fillColor("#242424");
+  for (const item of input.order.items) {
+    doc.text(`${item.productName} (${item.weightGrams} g)`, columns.name, y, { width: 260 });
+    doc.text(String(item.quantity), columns.qty, y);
+    doc.text(formatPrice(item.unitPriceCents, input.order.currency), columns.price, y);
+    doc.text(formatPrice(item.totalCents, input.order.currency), columns.total, y);
+    y += 20;
+  }
+
+  y += 10;
+  doc.moveTo(350, y).lineTo(545, y).strokeColor("#dddddd").stroke();
+  y += 10;
+
+  doc.fontSize(10).fillColor("#666666").text(t.subtotalLabel, 350, y);
+  doc.fillColor("#242424").text(formatPrice(input.order.subtotalCents, input.order.currency), columns.total, y);
+  y += 16;
+  doc.fillColor("#666666").text(t.shippingLabel, 350, y);
+  doc
+    .fillColor("#242424")
+    .text(
+      input.order.shippingCents === 0 ? t.freeShipping : formatPrice(input.order.shippingCents, input.order.currency),
+      columns.total,
+      y
+    );
+  if (input.order.discountCents > 0) {
+    y += 16;
+    doc
+      .fillColor("#666666")
+      .text(input.order.discountCode ? `${t.discountLabel} (${input.order.discountCode.code})` : t.discountLabel, 350, y);
+    doc
+      .fillColor("#242424")
+      .text(`−${formatPrice(input.order.discountCents, input.order.currency)}`, columns.total, y);
+  }
+  y += 20;
+  doc.fontSize(11).fillColor("#24352B").text(t.totalLabel, 350, y);
+  doc.text(formatPrice(input.totalCents, input.order.currency), columns.total, y);
+
+  doc
+    .fontSize(8)
+    .fillColor("#999999")
+    .text(t.legalNote, 50, 760, { width: 495 });
+
+  doc.end();
+  return done;
+}