pdf-e-signature/dist/hooks/usePDF.js

A React component that allows users to select positions for e-signatures on PDFs

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.usePDF = void 0;
var _react = require("react");
var _pdfLib = require("pdf-lib");
const usePDF = () => {
  const [scale, setScale] = (0, _react.useState)(1.5);
  const [currentPage, setCurrentPage] = (0, _react.useState)(1);
  const [numPages, setNumPages] = (0, _react.useState)(null);
  const [signedPdfUrl, setSignedPdfUrl] = (0, _react.useState)(null);
  const [isGeneratingPdf, setIsGeneratingPdf] = (0, _react.useState)(false);
  const onDocumentLoadSuccess = _ref => {
    let {
      numPages
    } = _ref;
    setNumPages(numPages);
    setCurrentPage(1);
  };
  const generateSignedPdf = async (pdfFile, signaturePositions) => {
    setIsGeneratingPdf(true);
    try {
      const arrayBuffer = await pdfFile.arrayBuffer();
      const pdfDoc = await _pdfLib.PDFDocument.load(arrayBuffer);
      for (const position of signaturePositions) {
        if (!position.signature) continue;
        const page = pdfDoc.getPages()[position.page - 1];
        const {
          width: pdfWidth,
          height: pdfHeight
        } = page.getSize();
        const signatureImage = await pdfDoc.embedPng(position.signature);
        const signatureWidth = 150;
        const signatureHeight = 50;
        const xPos = position.normalizedX * pdfWidth - signatureWidth / 2;
        const yPos = pdfHeight - position.normalizedY * pdfHeight - signatureHeight / 2;
        page.drawImage(signatureImage, {
          x: xPos,
          y: Math.max(0, Math.min(yPos, pdfHeight - signatureHeight)),
          width: signatureWidth,
          height: signatureHeight
        });
        if (position.timestamp) {
          page.drawText(position.timestamp, {
            x: xPos + 15,
            y: Math.max(0, Math.min(yPos - 15, pdfHeight - signatureHeight)),
            size: 8
          });
        }
      }
      const pdfBytes = await pdfDoc.save();
      const blob = new Blob([pdfBytes], {
        type: 'application/pdf'
      });
      const url = URL.createObjectURL(blob);
      setSignedPdfUrl(url);
      return blob;
    } catch (error) {
      console.error('Error generating signed PDF:', error);
      alert('Error generating signed PDF. Please try again.');
    } finally {
      setIsGeneratingPdf(false);
    }
  };
  return {
    scale,
    setScale,
    currentPage,
    setCurrentPage,
    numPages,
    signedPdfUrl,
    isGeneratingPdf,
    onDocumentLoadSuccess,
    generateSignedPdf,
    setSignedPdfUrl
  };
};
exports.usePDF = usePDF;