Improve and update billing flow

This commit updates various components in the billing flow due to a new schema that supports multiple line items per plan. The added flexibility rendered 'line-items-mapper.ts' redundant, which has been removed. Additionally, webhooks have been created for handling account membership insertions and deletions, as well as handling subscription deletions when an account is deleted. This message also introduces a new service to handle sending out invitation emails. Lastly, the validation of the billing provider has been improved for increased security and stability.

packages/features/team-accounts/src/server/services/account-invitations-webhook.service.ts

@@ -0,0 +1,105 @@
+import { SupabaseClient } from '@supabase/supabase-js';
+
+import { z } from 'zod';
+
+import { Mailer } from '@kit/mailers';
+import { Logger } from '@kit/shared/logger';
+import { Database } from '@kit/supabase/database';
+
+type Invitation = Database['public']['Tables']['invitations']['Row'];
+
+const invitePath = process.env.INVITATION_PAGE_PATH;
+const siteURL = process.env.NEXT_PUBLIC_SITE_URL;
+const productName = process.env.NEXT_PUBLIC_PRODUCT_NAME ?? '';
+const emailSender = process.env.EMAIL_SENDER;
+
+const env = z
+  .object({
+    invitePath: z.string().min(1),
+    siteURL: z.string().min(1),
+    productName: z.string(),
+    emailSender: z.string().email(),
+  })
+  .parse({
+    invitePath,
+    siteURL,
+    productName,
+    emailSender,
+  });
+
+export class AccountInvitationsWebhookService {
+  private namespace = 'accounts.invitations.webhook';
+
+  constructor(private readonly client: SupabaseClient<Database>) {}
+
+  async handleInvitationWebhook(invitation: Invitation) {
+    return this.dispatchInvitationEmail(invitation);
+  }
+
+  private async dispatchInvitationEmail(invitation: Invitation) {
+    const mailer = new Mailer();
+
+    const inviter = await this.client
+      .from('accounts')
+      .select('email, name')
+      .eq('id', invitation.invited_by)
+      .single();
+
+    if (inviter.error) {
+      throw inviter.error;
+    }
+
+    const team = await this.client
+      .from('accounts')
+      .select('name')
+      .eq('id', invitation.account_id)
+      .single();
+
+    if (team.error) {
+      throw team.error;
+    }
+
+    try {
+      const { renderInviteEmail } = await import('@kit/email-templates');
+
+      const html = renderInviteEmail({
+        link: this.getInvitationLink(invitation.invite_token),
+        invitedUserEmail: invitation.email,
+        inviter: inviter.data.name ?? inviter.data.email ?? '',
+        productName: env.productName,
+        teamName: team.data.name,
+      });
+
+      await mailer.sendEmail({
+        from: env.emailSender,
+        to: invitation.email,
+        subject: 'You have been invited to join a team',
+        html,
+      });
+
+      Logger.info('Invitation email sent', {
+        email: invitation.email,
+        account: invitation.account_id,
+        name: this.namespace,
+      });
+
+      return {
+        success: true,
+      };
+    } catch (error) {
+      Logger.warn(
+        { error, name: this.namespace },
+        'Failed to send invitation email',
+      );
+
+      return {
+        error,
+        success: false,
+      };
+    }
+  }
+
+  private getInvitationLink(token: string) {
+    return new URL(env.invitePath, env.siteURL).href + `?invite_token=${token}`;
+  }
+}