Add pay button

src/components/pay-button.tsx

@@ -0,0 +1,30 @@
+import { MachineSpec } from "../api";
+
+import "./pay-button.css"
+
+export default function VpsPayButton({ spec }: { spec: MachineSpec }) {
+    const serverUrl = "https://btcpay.v0l.io/api/v1/invoices";
+
+    function handleFormSubmit(event: React.FormEvent) {
+        event.preventDefault();
+        const form = event.target as HTMLFormElement;
+        const xhttp = new XMLHttpRequest();
+        xhttp.onreadystatechange = function () {
+            if (this.readyState == 4 && this.status == 200 && this.responseText) {
+                window.btcpay.appendInvoiceFrame(JSON.parse(this.responseText).invoiceId);
+            }
+        };
+        xhttp.open('POST', serverUrl, true);
+        xhttp.send(new FormData(form));
+    }
+
+    return <form method="POST" action={serverUrl} className="btcpay-form btcpay-form--block" onSubmit={handleFormSubmit}>
+        <input type="hidden" name="storeId" value="CdaHy1puLx4kLC9BG3A9mu88XNyLJukMJRuuhAfbDrxg" />
+        <input type="hidden" name="jsonResponse" value="true" />
+        <input type="hidden" name="orderId" value={spec.id} />
+        <input type="hidden" name="price" value={spec.cost.count} />
+        <input type="hidden" name="currency" value={spec.cost.currency} />
+        <input type="image" className="submit" name="submit" src="https://btcpay.v0l.io/img/paybutton/pay.svg"
+            alt="Pay with BTCPay Server, a Self-Hosted Bitcoin Payment Processor" />
+    </form>
+}