chore: setup the email notification for VAT

src/lib/storage/jobs/helpers/sendVatNotificationEmail.ts

@@ -0,0 +1,49 @@
+import { useDefaultEmailService } from '../../../../services/EmailService/EmailService';
+import { getStripe } from '../../../integrations/stripe';
+import Stripe from 'stripe';
+
+const stripe = getStripe();
+
+const sendVatNotificationEmail = async () => {
+  const emailService = useDefaultEmailService();
+  let hasMore = true;
+  let startingAfter: string | undefined = undefined;
+
+  while (hasMore) {
+    const subscriptions: Stripe.ApiList<Stripe.Subscription> =
+      await stripe.subscriptions.list({
+        limit: 100,
+        status: 'active',
+        starting_after: startingAfter,
+      });
+
+    for (const subscription of subscriptions.data) {
+      if (typeof subscription.customer === 'string') {
+        const customer = await stripe.customers.retrieve(subscription.customer);
+
+        if ('email' in customer) {
+          console.log({
+            email: customer.email,
+            currency: subscription.currency,
+          });
+          await emailService.sendVatNotificationEmail(
+            customer.email ?? `alexander+${subscription.id}@alemayhu.com`, // fallback to inform dev if email is not set
+            subscription.currency,
+            customer.name ?? 'there'
+          );
+        } else {
+          console.warn('Customer does not have an email');
+        }
+      }
+    }
+
+    hasMore = subscriptions.has_more;
+    if (hasMore) {
+      startingAfter = subscriptions.data[subscriptions.data.length - 1].id;
+    }
+  }
+};
+
+if (require.main === module) {
+  sendVatNotificationEmail().catch(console.error);
+}

src/services/EmailService/EmailService.ts

@@ -1,10 +1,15 @@
 import sgMail = require('@sendgrid/mail');
+import * as cheerio from 'cheerio';
+import * as fs from 'fs';
+import * as path from 'path';
 
 import {
   CONVERT_LINK_TEMPLATE,
   CONVERT_TEMPLATE,
   DEFAULT_SENDER,
   PASSWORD_RESET_TEMPLATE,
+  VAT_NOTIFICATION_TEMPLATE,
+  VAT_NOTIFICATIONS_LOG_PATH,
 } from './constants';
 import { isValidDeckName, addDeckNameSuffix } from '../../lib/anki/format';
 import { ClientResponse } from '@sendgrid/mail';
@@ -22,6 +27,11 @@ export interface IEmailService {
     message: string,
     attachments: Express.Multer.File[]
   ): Promise<EmailResponse>;
+  sendVatNotificationEmail(
+    email: string,
+    currency: string,
+    name: string
+  ): Promise<void>;
 }
 
 class EmailService implements IEmailService {
@@ -120,6 +130,77 @@ class EmailService implements IEmailService {
       return { didSend: false, error: e as Error };
     }
   }
+
+  private loadVatNotificationsSent(): Set<string> {
+    try {
+      // Ensure .2anki directory exists
+      const dir = path.dirname(VAT_NOTIFICATIONS_LOG_PATH);
+      if (!fs.existsSync(dir)) {
+        fs.mkdirSync(dir, { recursive: true });
+      }
+
+      if (fs.existsSync(VAT_NOTIFICATIONS_LOG_PATH)) {
+        const data = fs.readFileSync(VAT_NOTIFICATIONS_LOG_PATH, 'utf8');
+        return new Set(JSON.parse(data));
+      }
+    } catch (error) {
+      console.warn('Error loading VAT notifications log:', error);
+    }
+    return new Set();
+  }
+
+  private saveVatNotificationSent(email: string): void {
+    try {
+      const vatNotificationsSent = this.loadVatNotificationsSent();
+      vatNotificationsSent.add(email);
+      fs.writeFileSync(
+        VAT_NOTIFICATIONS_LOG_PATH,
+        JSON.stringify([...vatNotificationsSent])
+      );
+    } catch (error) {
+      console.error('Error saving VAT notification log:', error);
+    }
+  }
+
+  async sendVatNotificationEmail(
+    email: string,
+    currency: string,
+    name: string
+  ): Promise<void> {
+    const vatNotificationsSent = this.loadVatNotificationsSent();
+    if (vatNotificationsSent.has(email)) {
+      console.log(`Skipping ${email} - VAT notification already sent`);
+      return;
+    }
+
+    const amount = currency === 'eur' ? '€2' : '$2';
+    const markup = VAT_NOTIFICATION_TEMPLATE.replace(
+      '{{amount}}',
+      amount
+    ).replace('{{name}}', name || 'there');
+
+    // Convert HTML to text using cheerio
+    const $ = cheerio.load(markup);
+    const text = $('body').text().replace(/\s+/g, ' ').trim();
+
+    const msg = {
+      to: email,
+      from: this.defaultSender,
+      subject: '2anki.net - Upcoming Changes to VAT',
+      text,
+      html: markup,
+      replyTo: '[email protected]',
+    };
+
+    try {
+      await sgMail.send(msg);
+      this.saveVatNotificationSent(email);
+      console.log(`Successfully sent VAT notification to ${email}`);
+    } catch (error) {
+      console.error(`Failed to send VAT notification to ${email}:`, error);
+      throw error;
+    }
+  }
 }
 
 export class UnimplementedEmailService implements IEmailService {
@@ -150,6 +231,15 @@ export class UnimplementedEmailService implements IEmailService {
     );
     return Promise.resolve({ didSend: false });
   }
+
+  sendVatNotificationEmail(
+    email: string,
+    currency: string,
+    name: string
+  ): Promise<void> {
+    console.info('sendVatNotificationEmail not handled', email, currency, name);
+    return Promise.resolve();
+  }
 }
 
 export const useDefaultEmailService = () => {

src/services/EmailService/constants.ts

@@ -1,5 +1,6 @@
 import path from 'path';
 import fs from 'fs';
+import * as os from 'os';
 
 export const EMAIL_TEMPLATES_DIRECTORY = path.join(__dirname, 'templates');
 
@@ -19,3 +20,14 @@ export const CONVERT_LINK_TEMPLATE = fs.readFileSync(
 );
 
 export const DEFAULT_SENDER = '2anki.net <[email protected]>';
+
+export const VAT_NOTIFICATION_TEMPLATE = fs.readFileSync(
+  path.join(EMAIL_TEMPLATES_DIRECTORY, 'vat-notification.html'),
+  'utf8'
+);
+
+export const VAT_NOTIFICATIONS_LOG_PATH = path.join(
+  os.homedir(),
+  '.2anki',
+  'vat-notifications-sent.json'
+);

src/services/EmailService/templates/vat-notification.html

@@ -0,0 +1,28 @@
+<p>Hei {{name}},</p>
+
+<p>
+        We want to inform you about an upcoming change to your 2anki subscription. As a Norwegian company (Lær Smart
+        AS),
+        we are required by law to collect Value Added Tax (VAT) on our services.
+</p>
+
+<p>
+        <strong>What this means for your subscription</strong><br>
+        Your current monthly subscription costs {{amount}}. In the near future,
+        we will need to add 25% VAT to this amount, as required by Norwegian law.
+</p>
+
+<p>
+        We understand this change might affect your decision to continue using our service. If you wish to cancel your
+        subscription,
+        you can do so at any time using <a href="https://buy.stripe.com/cN2cPC6ek7RCbjGdQU">this link</a>.
+        If you have any questions or concerns, please email us at
+        <a href="mailto:[email protected]">[email protected]</a>.
+</p>
+
+<p style="margin-top: 2em; color: #666;">
+        --<br>
+        Happy learning,<br>
+        The 2anki Team<br>
+        <a href="https://2anki.net/" style="color: #0066cc; text-decoration: none;">2anki.net</a>
+</p>