PDF-Invoice-Generation-Provider

backend/src/app.module.ts

@@ -5,6 +5,7 @@ import { ConfigModule, ConfigService } from '@nestjs/config';
 import { TypeOrmModule } from '@nestjs/typeorm';
 import { AuthModule } from './auth/auth.module';
 import { UsersModule } from './users/users.module';
+import { InvoicesModule } from './invoices/invoices.module';
 import { APP_GUARD } from '@nestjs/core';
 import { JwtAuthGuard } from './auth/guard/jwt.auth.guard';
 import { ThrottlerModule, ThrottlerGuard } from '@nestjs/throttler';
@@ -82,6 +83,7 @@ import { NotificationsModule } from './notifications/notifications.module';
     EmailModule,
     AuthModule,
     UsersModule,
+    InvoicesModule,
     NewsletterModule,
     ContactModule,
     DashboardModule,

backend/src/invoices/invoices.module.ts

@@ -0,0 +1,8 @@
+import { Module } from '@nestjs/common';
+import { PdfInvoiceProvider } from './providers/pdf-invoice.provider';
+
+@Module({
+  providers: [PdfInvoiceProvider],
+  exports: [PdfInvoiceProvider],
+})
+export class InvoicesModule {}

backend/src/invoices/providers/pdf-invoice.provider.ts

@@ -0,0 +1,171 @@
+import { Injectable } from '@nestjs/common';
+import * as PDFDocument from 'pdfkit';
+import { Invoice } from '../../payments/entities/invoice.entity';
+import { Booking } from '../../bookings/entities/booking.entity';
+import { User } from '../../users/entities/user.entity';
+import { Workspace } from '../../workspaces/entities/workspace.entity';
+
+interface InvoiceWithRelations extends Invoice {
+  user: User;
+  booking: Booking & {
+    workspace: Workspace;
+  };
+}
+
+@Injectable()
+export class PdfInvoiceProvider {
+  async generate(invoice: InvoiceWithRelations): Promise<Buffer> {
+    return new Promise((resolve, reject) => {
+      try {
+        const doc = new PDFDocument({
+          size: 'A4',
+          margins: {
+            top: 50,
+            bottom: 50,
+            left: 50,
+            right: 50,
+          },
+        });
+
+        const chunks: Buffer[] = [];
+
+        doc.on('data', (chunk) => {
+          chunks.push(chunk);
+        });
+
+        doc.on('end', () => {
+          const pdfBuffer = Buffer.concat(chunks);
+          resolve(pdfBuffer);
+        });
+
+        doc.on('error', (error) => {
+          reject(error);
+        });
+
+        // Header Section
+        this.addHeader(doc);
+
+        // Invoice Metadata Section
+        this.addInvoiceMetadata(doc, invoice);
+
+        // Bill To Section
+        this.addBillToSection(doc, invoice.user);
+
+        // Service Details Section
+        this.addServiceDetails(doc, invoice.booking);
+
+        // Amount Summary Section
+        this.addAmountSummary(doc, invoice);
+
+        // Footer Section
+        this.addFooter(doc);
+
+        doc.end();
+      } catch (error) {
+        reject(error);
+      }
+    });
+  }
+
+  private addHeader(doc: typeof PDFDocument): void {
+    // ManageHub logo/name
+    doc.fontSize(24).font('Helvetica-Bold').text('ManageHub', 50, 50);
+
+    // TAX INVOICE title
+    doc.fontSize(18).font('Helvetica-Bold').text('TAX INVOICE', 50, 85);
+
+    // Add a line under the header
+    doc.moveTo(50, 110).lineTo(545, 110).stroke();
+  }
+
+  private addInvoiceMetadata(doc: typeof PDFDocument, invoice: InvoiceWithRelations): void {
+    const yPosition = 130;
+
+    doc.fontSize(12).font('Helvetica');
+
+    // Invoice Number
+    doc.text(`Invoice Number: ${invoice.invoiceNumber}`, 50, yPosition);
+
+    // Issue Date
+    doc.text(`Issue Date: ${invoice.createdAt.toLocaleDateString()}`, 50, yPosition + 20);
+
+    // Payment Date (if paid)
+    if (invoice.paidAt) {
+      doc.text(`Payment Date: ${invoice.paidAt.toLocaleDateString()}`, 50, yPosition + 40);
+    }
+
+    // Due Date
+    if (invoice.dueDate) {
+      doc.text(`Due Date: ${invoice.dueDate.toLocaleDateString()}`, 50, yPosition + 60);
+    }
+  }
+
+  private addBillToSection(doc: typeof PDFDocument, user: User): void {
+    const yPosition = 220;
+
+    doc.fontSize(14).font('Helvetica-Bold').text('Bill To:', 50, yPosition);
+
+    doc.fontSize(12).font('Helvetica');
+
+    // Member's full name
+    const fullName = user.fullName || user.email;
+    doc.text(fullName, 50, yPosition + 25);
+
+    // Email address
+    doc.text(user.email, 50, yPosition + 45);
+  }
+
+  private addServiceDetails(doc: typeof PDFDocument, booking: Booking & { workspace: Workspace }): void {
+    const yPosition = 320;
+
+    doc.fontSize(14).font('Helvetica-Bold').text('Service Details:', 50, yPosition);
+
+    doc.fontSize(12).font('Helvetica');
+
+    // Workspace name
+    doc.text(`Workspace: ${booking.workspace.name}`, 50, yPosition + 25);
+
+    // Plan type
+    doc.text(`Plan Type: ${booking.workspace.type}`, 50, yPosition + 45);
+
+    // Start date
+    doc.text(`Start Date: ${booking.startDate.toLocaleDateString()}`, 50, yPosition + 65);
+
+    // End date
+    doc.text(`End Date: ${booking.endDate.toLocaleDateString()}`, 50, yPosition + 85);
+
+    // Number of seats
+    doc.text(`Number of Seats: ${booking.seatCount}`, 50, yPosition + 105);
+  }
+
+  private addAmountSummary(doc: typeof PDFDocument, invoice: InvoiceWithRelations): void {
+    const yPosition = 460;
+
+    doc.fontSize(14).font('Helvetica-Bold').text('Amount Summary:', 50, yPosition);
+
+    doc.fontSize(12).font('Helvetica');
+
+    // Subtotal (same as total for now, but keeping structure)
+    const subtotal = invoice.amountKobo / 100; // Convert from kobo to Naira
+    doc.text(`Subtotal: ₦${subtotal.toFixed(2)}`, 50, yPosition + 25);
+
+    // Total amount
+    doc.font('Helvetica-Bold').text(`Total Amount: ₦${subtotal.toFixed(2)}`, 50, yPosition + 45);
+
+    // Status
+    const statusColor = invoice.status === 'PAID' ? 'green' : 'red';
+    doc.fillColor(statusColor).text(`Status: ${invoice.status}`, 50, yPosition + 65);
+    doc.fillColor('black'); // Reset color
+  }
+
+  private addFooter(doc: typeof PDFDocument): void {
+    // Move to bottom of page
+    doc.fontSize(10).font('Helvetica-Oblique');
+
+    const footerText = 'Thank you for your business';
+    const textWidth = doc.widthOfString(footerText);
+    const centerX = (doc.page.width - textWidth) / 2;
+
+    doc.text(footerText, centerX, doc.page.height - 80, { align: 'center' });
+  }
+}

backend/src/payments/entities/invoice.entity.ts

@@ -8,6 +8,7 @@ import {
   JoinColumn,
 } from 'typeorm';
 import { User } from '../../users/entities/user.entity';
+import { Booking } from '../../bookings/entities/booking.entity';
 import { InvoiceStatus } from '../enums/invoice-status.enum';
 
 @Entity('invoices')
@@ -25,6 +26,10 @@ export class Invoice {
   @Column('uuid', { nullable: true })
   bookingId: string;
 
+  @ManyToOne(() => Booking, { onDelete: 'RESTRICT' })
+  @JoinColumn({ name: 'bookingId' })
+  booking: Booking;
+
   @Column({ type: 'varchar', length: 50, unique: true })
   invoiceNumber: string;