@signpdf/placeholder-plain/dist/createBufferTrailer.js

Try to add a signature placeholder to a PDF using plain string modifications.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
/**
 * @param {Buffer} pdf
 * @param {import("./readPdf").ReadPdfReturnType} info
 * @param {Map<number, number>} addedReferences
 * @returns {Buffer}
 */
const createBufferTrailer = (pdf, info, addedReferences) => {
  let rows = [];
  rows[0] = '0000000000 65535 f '; // info.xref.tableRows[0];

  addedReferences.forEach((offset, index) => {
    const paddedOffset = `0000000000${offset}`.slice(-10);
    rows[index + 1] = `${index} 1\n${paddedOffset} 00000 n `;
  });
  rows = rows.filter(row => row !== undefined);
  return Buffer.concat([Buffer.from('xref\n'), Buffer.from(`${info.xref.startingIndex} 1\n`), Buffer.from(rows.join('\n')), Buffer.from('\ntrailer\n'), Buffer.from('<<\n'), Buffer.from(`/Size ${info.xref.maxIndex + 1}\n`), Buffer.from(`/Root ${info.rootRef}\n`), Buffer.from(info.infoRef ? `/Info ${info.infoRef}\n` : ''), Buffer.from(`/Prev ${info.xRefPosition}\n`), Buffer.from('>>\n'), Buffer.from('startxref\n'), Buffer.from(`${pdf.length}\n`), Buffer.from('%%EOF')]);
};
var _default = exports.default = createBufferTrailer;