Invoicing

Invoicing allows you to send professional payment requests to customers. Customers can view the invoice and pay directly from the invoice page.

**Key Features:**
- Professional invoice templates
- Customizable line items and descriptions
- Payment tracking and status updates
- Send invoices via email or shareable link

Create an invoice by generating a checkout link with invoice details:

```typescript
await createCheckoutLink("biz_your_business_id", {
  planName: "Website Development",
  plan: "web-dev-invoice-001",
  description: `
Invoice #001
Client: Acme Corporation
Date: March 15, 2024

Services:
- Homepage redesign: $500.00
- Contact form implementation: $200.00
- Mobile responsive fixes: $150.00

Total: $850.00
  `.trim(),
  price: "850.00",
  billing: "one-time",
});
```

**Invoice Details:**
- `planName`: Invoice title or service name
- `plan`: Unique invoice identifier
- `description`: Full invoice details including line items
- `price`: Total amount due

**Share Invoice Link Directly:**
```tsx
import Link from "next/link";

// Send customer to invoice page
<Link href="/checkout-links/plan_invoice001">
  View Invoice
</Link>
```

**Email Invoice:**
Use your preferred email service to send the invoice link:

```typescript
import { Resend } from "resend";

const resend = new Resend(process.env.RESEND_API_KEY);

await resend.emails.send({
  from: "invoices@yourcompany.com",
  to: "customer@example.com",
  subject: "Invoice #001 - $850.00 Due",
  html: `
    <h1>Invoice #001</h1>
    <p>Dear Customer,</p>
    <p>Please find your invoice attached.</p>
    <p>Total: $850.00</p>
    <a href="https://pay.yeld.app/plan_invoice001">
      Pay Now
    </a>
  `,
});
```

Track invoice status through your dashboard or API:

```typescript
// Get invoice status
const invoice = await getCheckoutLinkByPlanId("plan_invoice001");

// Check if payment was received
const sessions = await db
  .select()
  .from(checkoutSessions)
  .where(
    and(
      eq(checkoutSessions.checkoutLinkId, invoice.id),
      eq(checkoutSessions.status, "confirmed")
    )
  );

const isPaid = sessions.length > 0;
```

**Invoice Statuses:**
- `pending`: Invoice created, awaiting payment
- `paid`: Payment confirmed
- `overdue`: Payment past due date (if applicable)