2025-07-08 15:53:01 +02:00

339 lines
9.4 KiB
TypeScript

import { saveAs } from 'file-saver';
import { PDFDocument, rgb, StandardFonts } from 'pdf-lib';
const separator = '\x1f';
export interface CustomerInfo {
firstName: string;
lastName: string;
postalAddress: string;
email: string;
}
export interface NotaryInfo {
name: string;
// Add more notary fields as needed
}
export interface Metadata {
fileName: string,
createdAt: Date,
isDeleted: boolean,
updatedAt: Date,
commitmentId: string,
documentUid: string;
documentType: string;
merkleProof: string;
}
export interface CertificateData {
customer: CustomerInfo;
notary: NotaryInfo;
folderUid: string;
documentHash: string;
metadata: Metadata;
}
export default class PdfService {
private static instance: PdfService;
public static getInstance(): PdfService {
if (!PdfService.instance) {
PdfService.instance = new PdfService();
}
return PdfService.instance;
}
/**
* Generate a certificate PDF for a document
* @param certificateData - Data needed for the certificate
* @returns Promise<Blob> - The generated PDF as a blob
*/
public async generateCertificate(certificateData: CertificateData): Promise<Blob> {
try {
const pdfDoc = await PDFDocument.create();
const page = pdfDoc.addPage([595, 842]); // A4 size
const { width, height } = page.getSize();
const helveticaFont = await pdfDoc.embedFont(StandardFonts.Helvetica);
const helveticaBoldFont = await pdfDoc.embedFont(StandardFonts.HelveticaBold);
const helveticaObliqueFont = await pdfDoc.embedFont(StandardFonts.HelveticaOblique);
let y = height - 40; // Start 40pt from the top
const leftMargin = 20;
const rightSectionX = 320;
const lineSpacing = 16;
// Notary Information Section (Top Left)
page.drawText('Notaire Validateur:', {
x: leftMargin,
y: y,
size: 12,
font: helveticaBoldFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
page.drawText(certificateData.notary.name, {
x: leftMargin,
y: y,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
// Customer Information Section (Top Right)
let yRight = height - 40;
page.drawText('Fournisseur de Document:', {
x: rightSectionX,
y: yRight,
size: 12,
font: helveticaBoldFont,
color: rgb(0, 0, 0)
});
yRight -= lineSpacing;
page.drawText(`${certificateData.customer.firstName} ${certificateData.customer.lastName}`, {
x: rightSectionX,
y: yRight,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
yRight -= lineSpacing;
page.drawText(certificateData.customer.email, {
x: rightSectionX,
y: yRight,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
yRight -= lineSpacing;
page.drawText(certificateData.customer.postalAddress, {
x: rightSectionX,
y: yRight,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
// Centered Title
y -= 4 * lineSpacing; // Add more space between header and title
const titleText = 'Certificat de Validation de Document';
const titleWidth = helveticaBoldFont.widthOfTextAtSize(titleText, 20);
page.drawText(titleText, {
x: (width - titleWidth) / 2,
y: y,
size: 20,
font: helveticaBoldFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
// Add a line separator
page.drawLine({
start: { x: leftMargin, y: y },
end: { x: width - leftMargin, y: y },
thickness: 0.5,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
// Document Information Section
page.drawText('Informations du Document', {
x: leftMargin,
y: y,
size: 12,
font: helveticaBoldFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
page.drawText(`UID du Dossier: ${certificateData.folderUid}`, {
x: leftMargin,
y: y,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
page.drawText(`Type de Document: ${certificateData.metadata.documentType}`, {
x: leftMargin,
y: y,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
page.drawText(`Nom du fichier: ${certificateData.metadata.fileName}`, {
x: leftMargin,
y: y,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
page.drawText(`Créé le: ${certificateData.metadata.createdAt.toLocaleDateString('fr-FR')}`, {
x: leftMargin,
y: y,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
page.drawText(`Dernière modification: ${certificateData.metadata.updatedAt.toLocaleDateString('fr-FR')}`, {
x: leftMargin,
y: y,
size: 12,
font: helveticaFont,
color: rgb(0, 0, 0)
});
y -= lineSpacing;
const keywords = [
certificateData.documentHash,
certificateData.metadata.commitmentId,
JSON.stringify(certificateData.metadata.merkleProof)
];
pdfDoc.setKeywords([keywords.join(separator)]);
// Add explanatory text about certificate usage
const explanatoryText = "Ce certificat doit être utilisé avec le document qu'il certifie pour être vérifié sur la page dédiée. Le document correspondant à ce certificat doit être téléchargé depuis LeCoffre et peut être conservé avec le certificat tant qu'il n'est pas modifié.";
const explanatoryLines = this.splitTextToFit(helveticaObliqueFont, explanatoryText, width - (2 * leftMargin), 11);
y -= (explanatoryLines.length * 12) + 40; // Space after verification data
explanatoryLines.forEach((line, index) => {
page.drawText(line, {
x: leftMargin,
y: y - (index * 14), // Slightly more spacing for readability
size: 11,
font: helveticaObliqueFont,
color: rgb(0.3, 0.3, 0.3) // Slightly grayed out to distinguish from main content
});
});
// Footer
const footerText1 = `Page 1 sur 1`;
const footerText2 = `Généré le ${new Date().toLocaleString('fr-FR')}`;
const footerWidth1 = helveticaObliqueFont.widthOfTextAtSize(footerText1, 10);
const footerWidth2 = helveticaObliqueFont.widthOfTextAtSize(footerText2, 10);
page.drawText(footerText1, {
x: (width - footerWidth1) / 2,
y: 35,
size: 10,
font: helveticaObliqueFont,
color: rgb(0, 0, 0)
});
page.drawText(footerText2, {
x: (width - footerWidth2) / 2,
y: 25,
size: 10,
font: helveticaObliqueFont,
color: rgb(0, 0, 0)
});
const pdfBytes = await pdfDoc.save();
return new Blob([pdfBytes], { type: 'application/pdf' });
} catch (error) {
console.error('Error generating certificate:', error);
throw new Error('Failed to generate certificate');
}
}
/**
* Split text to fit within a specified width
* @param font - PDF font instance
* @param text - Text to split
* @param maxWidth - Maximum width in points
* @param fontSize - Font size
* @returns Array of text lines
*/
private splitTextToFit(font: any, text: string, maxWidth: number, fontSize: number): string[] {
const lines: string[] = [];
let currentLine = '';
// Split by characters (pdf-lib doesn't have word-level text measurement)
const chars = text.split('');
for (const char of chars) {
const testLine = currentLine + char;
const testWidth = font.widthOfTextAtSize(testLine, fontSize);
if (testWidth <= maxWidth) {
currentLine = testLine;
} else {
if (currentLine) {
lines.push(currentLine);
currentLine = char;
} else {
// If even a single character is too wide, force a break
lines.push(char);
}
}
}
if (currentLine) {
lines.push(currentLine);
}
return lines;
}
/**
* Download a certificate PDF
* @param certificateData - Data needed for the certificate
* @param filename - Optional filename for the download
*/
public async downloadCertificate(certificateData: CertificateData, filename?: string): Promise<void> {
try {
const pdfBlob = await this.generateCertificate(certificateData);
const defaultFilename = `certificate_${certificateData.metadata.documentUid}_${new Date().toISOString().split('T')[0]}.pdf`;
saveAs(pdfBlob, filename || defaultFilename);
} catch (error) {
console.error('Error downloading certificate:', error);
throw error;
}
}
/**
* Parse a PDF certificate and extract document information
* @param pdfBlob - The PDF file as a blob
* @returns Promise<{documentHash: string, documentUid: string, commitmentId: string, merkleProof?: string}> - Extracted information
*/
public async parseCertificate(certificateFile: File): Promise<{ documentHash: string, commitmentId: string, merkleProof: any }> {
return new Promise((resolve, reject) => {
const fileReader = new FileReader();
fileReader.onload = async () => {
try {
// Read the metadata and get the validation data from the keywords
const pdfDoc = await PDFDocument.load(await certificateFile.arrayBuffer());
const keywords = pdfDoc.getKeywords()?.split(separator);
if (!keywords) {
throw new Error("No keywords found in certificate");
}
if (keywords.length !== 3) {
throw new Error("Invalid keywords found in certificate");
}
const documentHash = keywords[0];
const commitmentId = keywords[1];
const merkleProof = keywords[2];
if (!documentHash || !commitmentId || !merkleProof) {
throw new Error("Invalid keywords found in certificate");
}
resolve({ documentHash, commitmentId, merkleProof });
} catch (error) {
reject(error);
}
};
fileReader.onerror = () => {
reject(new Error('Failed to read PDF file'));
};
fileReader.readAsArrayBuffer(certificateFile);
});
}
}