feat: add MailService.cashboxExport and email template

myteamwallet_backend/src/mail/mail-templates/cashbox-export.hbs

@@ -0,0 +1,5 @@
+{{#> layout}}
+<p>Hallo,</p>
+<p>im Anhang findest du den automatischen Kassenbuch-Export für <strong>{{teamName}}</strong> für den Zeitraum {{from}} bis {{to}}.</p>
+<p>Diese E-Mail wurde automatisch von TeamWallet verschickt und benötigt keine weitere Aktion.</p>
+{{/layout}}

myteamwallet_backend/src/mail/mail-templates/mail-templates.spec.ts

@@ -60,4 +60,20 @@ describe('mail templates rendering', () => {
     expect(html).toContain('Hallo,');
     expect(html).not.toContain('Hallo Max,');
   });
+
+  it('renders cashbox-export.hbs with team name and period', () => {
+    const source = fs.readFileSync(path.join(templatesDir, 'cashbox-export.hbs'), 'utf-8');
+    const html = Handlebars.compile(source, { strict: true })({
+      title: 'Kassenbuch-Export Team A',
+      year: 2026,
+      teamName: 'Team A',
+      from: '2026-08-01',
+      to: '2026-08-31',
+    });
+
+    expect(html).toContain('TeamWallet');
+    expect(html).toContain('Team A');
+    expect(html).toContain('2026-08-01');
+    expect(html).toContain('2026-08-31');
+  });
 });

myteamwallet_backend/src/mail/mail.service.spec.ts

@@ -58,4 +58,28 @@ describe('MailService', () => {
     const call = sendMail.mock.calls[0][0];
     expect(call.context.firstName).toBeUndefined();
   });
+
+  it('sends the cashbox export mail with the PDF attachment', async () => {
+    const attachment = Buffer.from('%PDF-1.4 fake');
+
+    await service.cashboxExport(
+      {
+        to: 'vorstand@example.com, kassier@example.com',
+        data: { teamName: 'Team A', from: '2026-08-01', to: '2026-08-31' },
+      },
+      attachment,
+      'kassenbuch_team-a_2026-08-01_2026-08-31.pdf',
+    );
+
+    expect(sendMail).toHaveBeenCalledTimes(1);
+    const call = sendMail.mock.calls[0][0];
+    expect(call.to).toBe('vorstand@example.com, kassier@example.com');
+    expect(call.template).toBe('cashbox-export');
+    expect(call.context.teamName).toBe('Team A');
+    expect(call.context.from).toBe('2026-08-01');
+    expect(call.context.to).toBe('2026-08-31');
+    expect(call.attachments).toEqual([
+      { filename: 'kassenbuch_team-a_2026-08-01_2026-08-31.pdf', content: attachment },
+    ]);
+  });
 });

myteamwallet_backend/src/mail/mail.service.ts

@@ -55,4 +55,24 @@ export class MailService {
       },
     });
   }
+
+  async cashboxExport(
+    mailData: MailData<{ teamName: string; from: string; to: string }>,
+    attachment: Buffer,
+    filename: string,
+  ): Promise<void> {
+    await this.mailerService.sendMail({
+      to: mailData.to,
+      subject: `Kassenbuch-Export ${mailData.data.teamName}`,
+      template: 'cashbox-export',
+      context: {
+        title: `Kassenbuch-Export ${mailData.data.teamName}`,
+        year: new Date().getFullYear(),
+        teamName: mailData.data.teamName,
+        from: mailData.data.from,
+        to: mailData.data.to,
+      },
+      attachments: [{ filename, content: attachment }],
+    });
+  }
 }