feat: add notification service for sweep and claim events

backend/package.json

@@ -27,6 +27,7 @@
     "@nestjs/common": "^11.0.1",
     "@nestjs/config": "^4.0.3",
     "@nestjs/core": "^11.0.1",
+    "@nestjs/event-emitter": "^3.0.1",
     "@nestjs/jwt": "^11.0.2",
     "@nestjs/passport": "^11.0.5",
     "@nestjs/platform-express": "^11.0.1",

backend/src/app.module.ts

@@ -2,6 +2,7 @@ import { Module } from '@nestjs/common';
 import { ConfigModule } from '@nestjs/config';
 import { ThrottlerGuard, ThrottlerModule } from '@nestjs/throttler';
 import { APP_GUARD } from '@nestjs/core';
+import { EventEmitterModule } from '@nestjs/event-emitter';
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
 import configuration from './config/configuration';
@@ -20,6 +21,7 @@ import { ClaimsModule } from './modules/claims/claims.module';
 import { DisputesModule } from './modules/disputes/disputes.module';
 import { AdminAnalyticsModule } from './modules/admin-analytics/admin-analytics.module';
 import { SavingsModule } from './modules/savings/savings.module';
+import { NotificationsModule } from './modules/notifications/notification.module';
 
 @Module({
   imports: [
@@ -32,6 +34,7 @@ import { SavingsModule } from './modules/savings/savings.module';
         abortEarly: true,
       },
     }),
+    EventEmitterModule.forRoot(),
     TypeOrmModule.forRootAsync({
       inject: [ConfigService],
       useFactory: (configService: ConfigService) => ({
@@ -53,6 +56,7 @@ import { SavingsModule } from './modules/savings/savings.module';
     DisputesModule,
     AdminAnalyticsModule,
     SavingsModule,
+    NotificationsModule,
     ThrottlerModule.forRoot([
       {
         ttl: 60000,

backend/src/modules/claims/claims.service.spec.ts

@@ -4,6 +4,7 @@ import { getRepositoryToken } from '@nestjs/typeorm';
 import { MedicalClaim, ClaimStatus } from './entities/medical-claim.entity';
 import { Repository } from 'typeorm';
 import { HospitalIntegrationService } from '../hospital-integration/hospital-integration.service';
+import { EventEmitter2 } from '@nestjs/event-emitter';
 
 describe('ClaimsService', () => {
   let service: ClaimsService;
@@ -37,6 +38,10 @@ describe('ClaimsService', () => {
           provide: HospitalIntegrationService,
           useValue: mockHospitalIntegrationService,
         },
+        {
+          provide: EventEmitter2,
+          useValue: { emit: jest.fn() },
+        },
       ],
     }).compile();
 

backend/src/modules/claims/claims.service.ts

@@ -1,9 +1,11 @@
 import { Injectable, Logger } from '@nestjs/common';
 import { InjectRepository } from '@nestjs/typeorm';
 import { Repository } from 'typeorm';
+import { EventEmitter2 } from '@nestjs/event-emitter';
 import { MedicalClaim, ClaimStatus } from './entities/medical-claim.entity';
 import { CreateClaimDto } from './dto/create-claim.dto';
 import { HospitalIntegrationService } from '../hospital-integration/hospital-integration.service';
+import { ClaimUpdatedEvent } from '../notifications/events/claim-updated.event';
 
 @Injectable()
 export class ClaimsService {
@@ -13,6 +15,7 @@ export class ClaimsService {
     @InjectRepository(MedicalClaim)
     private readonly claimsRepository: Repository<MedicalClaim>,
     private readonly hospitalIntegrationService: HospitalIntegrationService,
+    private readonly eventEmitter: EventEmitter2,
   ) { }
 
   async createClaim(createClaimDto: CreateClaimDto): Promise<MedicalClaim> {
@@ -51,13 +54,60 @@ export class ClaimsService {
       claim.status = verification.verified ? ClaimStatus.APPROVED : ClaimStatus.REJECTED;
       claim.notes = verification.notes || claim.notes;
 
-      return await this.claimsRepository.save(claim);
+      const saved = await this.claimsRepository.save(claim);
+
+      this.eventEmitter.emit(
+        'claim.updated',
+        new ClaimUpdatedEvent(
+          saved.id,
+          saved.patientName,
+          '',
+          saved.hospitalName,
+          Number(saved.claimAmount),
+          saved.status,
+          saved.notes,
+        ),
+      );
+
+      return saved;
     } catch (error) {
       this.logger.error(`Failed to verify claim ${claimId}:`, error);
       throw error;
     }
   }
 
+  async updateClaimStatus(
+    claimId: string,
+    status: ClaimStatus,
+    patientEmail: string,
+    notes?: string,
+  ): Promise<MedicalClaim> {
+    const claim = await this.findOne(claimId);
+    if (!claim) {
+      throw new Error('Claim not found');
+    }
+
+    claim.status = status;
+    if (notes) claim.notes = notes;
+
+    const saved = await this.claimsRepository.save(claim);
+
+    this.eventEmitter.emit(
+      'claim.updated',
+      new ClaimUpdatedEvent(
+        saved.id,
+        saved.patientName,
+        patientEmail,
+        saved.hospitalName,
+        Number(saved.claimAmount),
+        saved.status,
+        saved.notes,
+      ),
+    );
+
+    return saved;
+  }
+
   async fetchHospitalClaimData(hospitalId: string, claimId: string) {
     return await this.hospitalIntegrationService.fetchClaimData(hospitalId, claimId);
   }

backend/src/modules/mail/mail.service.ts

@@ -1,5 +1,6 @@
 import { Injectable, Logger } from '@nestjs/common';
 import { MailerService } from '@nestjs-modules/mailer';
+import { ClaimStatus } from '../claims/entities/medical-claim.entity';
 
 @Injectable()
 export class MailService {
@@ -22,4 +23,52 @@ export class MailService {
       this.logger.error(`Failed to send welcome email to ${userEmail}`, error);
     }
   }
+
+  async sendSweepCompleted(
+    userEmail: string,
+    userName: string,
+    productName: string,
+    amount: number,
+    txHash?: string,
+  ): Promise<void> {
+    try {
+      await this.mailerService.sendMail({
+        to: userEmail,
+        subject: 'Your Nestera account sweep was successful',
+        template: './sweep-completed',
+        context: { userName, productName, amount, txHash },
+      });
+      this.logger.log(`Sweep-completed email sent to ${userEmail}`);
+    } catch (error) {
+      this.logger.error(
+        `Failed to send sweep-completed email to ${userEmail}`,
+        error,
+      );
+    }
+  }
+
+  async sendClaimUpdated(
+    patientEmail: string,
+    patientName: string,
+    claimId: string,
+    hospitalName: string,
+    claimAmount: number,
+    status: ClaimStatus,
+    notes?: string,
+  ): Promise<void> {
+    try {
+      await this.mailerService.sendMail({
+        to: patientEmail,
+        subject: `Your medical claim status has been updated to ${status}`,
+        template: './claim-updated',
+        context: { patientName, claimId, hospitalName, claimAmount, status, notes },
+      });
+      this.logger.log(`Claim-updated email sent to ${patientEmail}`);
+    } catch (error) {
+      this.logger.error(
+        `Failed to send claim-updated email to ${patientEmail}`,
+        error,
+      );
+    }
+  }
 }

backend/src/modules/mail/templates/claim-updated.hbs

@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Claim Status Update – Nestera</title>
+</head>
+<body>
+  <h1>Medical Claim Status Update</h1>
+  <p>Hi {{patientName}},</p>
+  <p>Your medical claim has been updated. Below are the details:</p>
+  <table>
+    <tr><td><strong>Claim ID</strong></td><td>{{claimId}}</td></tr>
+    <tr><td><strong>Hospital</strong></td><td>{{hospitalName}}</td></tr>
+    <tr><td><strong>Claim Amount</strong></td><td>{{claimAmount}}</td></tr>
+    <tr><td><strong>Status</strong></td><td>{{status}}</td></tr>
+    {{#if notes}}
+    <tr><td><strong>Notes</strong></td><td>{{notes}}</td></tr>
+    {{/if}}
+  </table>
+  <p>If you have any questions, please contact our support team.</p>
+  <br>
+  <p>Best regards,<br>The Nestera Team</p>
+</body>
+</html>

backend/src/modules/mail/templates/sweep-completed.hbs

@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <meta charset="utf-8">
+  <title>Sweep Completed – Nestera</title>
+</head>
+<body>
+  <h1>Account Sweep Successful</h1>
+  <p>Hi {{userName}},</p>
+  <p>Your savings account sweep has been completed successfully.</p>
+  <table>
+    <tr><td><strong>Product</strong></td><td>{{productName}}</td></tr>
+    <tr><td><strong>Amount Swept</strong></td><td>{{amount}}</td></tr>
+    {{#if txHash}}
+    <tr><td><strong>Transaction Hash</strong></td><td>{{txHash}}</td></tr>
+    {{/if}}
+  </table>
+  <p>The funds have been transferred to your designated account.</p>
+  <br>
+  <p>Best regards,<br>The Nestera Team</p>
+</body>
+</html>

backend/src/modules/notifications/entities/notification.entity.ts

@@ -0,0 +1,38 @@
+import {
+  Entity,
+  Column,
+  PrimaryGeneratedColumn,
+  CreateDateColumn,
+} from 'typeorm';
+
+export enum NotificationType {
+  SWEEP_COMPLETED = 'SWEEP_COMPLETED',
+  CLAIM_UPDATED = 'CLAIM_UPDATED',
+}
+
+@Entity('notifications')
+export class Notification {
+  @PrimaryGeneratedColumn('uuid')
+  id: string;
+
+  @Column('uuid')
+  userId: string;
+
+  @Column({ type: 'enum', enum: NotificationType })
+  type: NotificationType;
+
+  @Column()
+  title: string;
+
+  @Column('text')
+  message: string;
+
+  @Column({ nullable: true })
+  referenceId: string;
+
+  @Column({ default: false })
+  isRead: boolean;
+
+  @CreateDateColumn()
+  createdAt: Date;
+}

backend/src/modules/notifications/events/claim-updated.event.ts

@@ -0,0 +1,13 @@
+import { ClaimStatus } from '../../claims/entities/medical-claim.entity';
+
+export class ClaimUpdatedEvent {
+  constructor(
+    public readonly claimId: string,
+    public readonly patientName: string,
+    public readonly patientEmail: string,
+    public readonly hospitalName: string,
+    public readonly claimAmount: number,
+    public readonly status: ClaimStatus,
+    public readonly notes?: string,
+  ) {}
+}

backend/src/modules/notifications/events/sweep-completed.event.ts

@@ -0,0 +1,11 @@
+export class SweepCompletedEvent {
+  constructor(
+    public readonly userId: string,
+    public readonly userEmail: string,
+    public readonly userName: string,
+    public readonly subscriptionId: string,
+    public readonly productName: string,
+    public readonly amount: number,
+    public readonly txHash?: string,
+  ) {}
+}

backend/src/modules/notifications/notification.module.ts

@@ -0,0 +1,12 @@
+import { Module } from '@nestjs/common';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { Notification } from './entities/notification.entity';
+import { NotificationService } from './notification.service';
+import { MailModule } from '../mail/mail.module';
+
+@Module({
+  imports: [TypeOrmModule.forFeature([Notification]), MailModule],
+  providers: [NotificationService],
+  exports: [NotificationService],
+})
+export class NotificationsModule {}