PDF generation

src/helpers/persian-pdf-document.ts

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+import { existsSync } from "node:fs";
+import { join } from "node:path";
+import type PDFDocumentType from "pdfkit";
+import {
+  isMostlyAscii,
+  pdfKitRtlKeyValue,
+  pdfKitRtlParagraph,
+} from "./persian-pdf-text";
+
+// pdfkit publishes CJS (`module.exports = PDFDocument`) without a `.default` export.
+// eslint-disable-next-line @typescript-eslint/no-require-imports
+const PDFDocument = require("pdfkit") as typeof PDFDocumentType;
+
+const PAGE_WIDTH = 595.28;
+const MARGIN = 50;
+const CONTENT_WIDTH = PAGE_WIDTH - MARGIN * 2;
+const LABEL_COLUMN_WIDTH = CONTENT_WIDTH * 0.44;
+const VALUE_COLUMN_WIDTH = CONTENT_WIDTH * 0.5;
+const VALUE_COLUMN_X = MARGIN;
+const COLON_X = MARGIN + VALUE_COLUMN_WIDTH + 4;
+const LABEL_COLUMN_X = COLON_X + 10;
+
+function resolveFontFile(variant: "regular" | "bold"): string {
+  const file =
+    variant === "bold"
+      ? "NotoKufiArabic-Bold.ttf"
+      : "NotoKufiArabic-Regular.ttf";
+  const candidates = [
+    join(process.cwd(), "assets", "fonts", file),
+    join(process.cwd(), "dist", "fonts", file),
+    join(process.cwd(), "dist", "assets", "fonts", file),
+    join("/usr/share/fonts/truetype/noto", file),
+  ];
+  for (const path of candidates) {
+    if (existsSync(path)) return path;
+  }
+  throw new Error(
+    `Persian PDF font not found (${file}). Place it under assets/fonts/ or install noto fonts on the host.`,
+  );
+}
+
+export type PersianPdfDocument = InstanceType<typeof PDFDocument> & {
+  addTitle: (text: string) => void;
+  addSection: (text: string) => void;
+  addKeyValue: (label: string, value?: string | number | null) => void;
+  addBlank: (lines?: number) => void;
+};
+
+function drawRtlLine(
+  doc: InstanceType<typeof PDFDocument>,
+  text: string,
+  fontSize: number,
+  bold: boolean,
+): void {
+  const y = doc.y;
+  doc
+    .font(bold ? "FaBold" : "FaRegular")
+    .fontSize(fontSize)
+    .text(pdfKitRtlParagraph(text), MARGIN, y, {
+      width: CONTENT_WIDTH,
+      align: "right",
+      lineBreak: false,
+    });
+  doc.moveDown(fontSize > 12 ? 0.55 : 0.45);
+}
+
+function drawKeyValueRow(
+  doc: InstanceType<typeof PDFDocument>,
+  label: string,
+  value: string,
+): void {
+  const y = doc.y;
+  const { label: faLabel, value: faValue } = pdfKitRtlKeyValue(label, value);
+
+  if (isMostlyAscii(faValue)) {
+    doc.font("Helvetica").fontSize(10).text(faValue, VALUE_COLUMN_X, y, {
+      width: VALUE_COLUMN_WIDTH,
+      align: "left",
+      lineBreak: false,
+    });
+  } else {
+    doc.font("FaRegular").fontSize(10).text(faValue, VALUE_COLUMN_X, y, {
+      width: VALUE_COLUMN_WIDTH,
+      align: "left",
+      lineBreak: false,
+    });
+  }
+
+  doc.font("Helvetica").fontSize(10).text(":", COLON_X, y, {
+    lineBreak: false,
+  });
+
+  doc.font("FaRegular").fontSize(10).text(faLabel, LABEL_COLUMN_X, y, {
+    width: LABEL_COLUMN_WIDTH,
+    align: "right",
+    lineBreak: false,
+  });
+
+  doc.moveDown(0.5);
+}
+
+export function createPersianPdfDocument(): PersianPdfDocument {
+  const doc = new PDFDocument({
+    size: "A4",
+    margin: MARGIN,
+    autoFirstPage: true,
+  }) as PersianPdfDocument;
+
+  doc.registerFont("FaRegular", resolveFontFile("regular"));
+  doc.registerFont("FaBold", resolveFontFile("bold"));
+  doc.font("FaRegular");
+
+  doc.addTitle = (text: string) => {
+    doc.moveDown(0.2);
+    drawRtlLine(doc, text, 16, true);
+    doc.font("FaRegular").fontSize(10);
+    doc.moveDown(0.15);
+  };
+
+  doc.addSection = (text: string) => {
+    doc.moveDown(0.5);
+    drawRtlLine(doc, text, 13, true);
+    doc.font("FaRegular").fontSize(10);
+    doc.moveDown(0.1);
+  };
+
+  doc.addKeyValue = (label: string, value?: string | number | null) => {
+    const v =
+      value === undefined || value === null || value === ""
+        ? "-"
+        : String(value);
+    drawKeyValueRow(doc, label, v);
+  };
+
+  doc.addBlank = (lines = 1) => {
+    doc.moveDown(lines * 0.35);
+  };
+
+  return doc;
+}
+
+export function persianPdfToBuffer(
+  doc: InstanceType<typeof PDFDocument>,
+): Promise<Buffer> {
+  return new Promise((resolve, reject) => {
+    const chunks: Buffer[] = [];
+    doc.on("data", (chunk: Buffer) => chunks.push(chunk));
+    doc.on("end", () => resolve(Buffer.concat(chunks)));
+    doc.on("error", reject);
+    doc.end();
+  });
+}