feat: voucher crud and list

app/vouchers/[id]/page.tsx

@@ -0,0 +1,72 @@
+"use client";
+import { use, useEffect, useState } from "react";
+import Link from "next/link";
+import { formatEuro } from "@/lib/vouchers";
+
+type Voucher = {
+  id: number;
+  name: string;
+  anbieter: string;
+  wertCents: number;
+  restCents: number;
+  ablaufdatum: string | null;
+  codeText: string | null;
+  kategorie: string | null;
+  notiz: string | null;
+  status: string;
+};
+
+export default function VoucherDetailPage({ params }: { params: Promise<{ id: string }> }) {
+  const { id } = use(params);
+  const [v, setV] = useState<Voucher | null>(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState("");
+
+  useEffect(() => {
+    fetch(`/api/vouchers/${id}`)
+      .then((r) => (r.ok ? r.json() : Promise.reject(new Error("not found"))))
+      .then((d) => setV(d))
+      .catch(() => setError("Gutschein nicht gefunden"))
+      .finally(() => setLoading(false));
+  }, [id]);
+
+  async function redeem() {
+    const res = await fetch(`/api/vouchers/${id}`, {
+      method: "POST",
+      headers: { "content-type": "application/json" },
+      body: JSON.stringify({ action: "redeem" }),
+    });
+    if (res.ok) setV(await res.json());
+  }
+
+  if (loading) return <main className="mx-auto max-w-xl animate-pulse space-y-2 p-6"><div className="h-6 w-1/2 bg-gray-200" /><div className="h-4 w-1/3 bg-gray-100" /></main>;
+  if (error || !v)
+    return (
+      <main className="mx-auto max-w-xl space-y-4 p-6">
+        <p>{error}</p>
+        <Link href="/" className="underline">Zurück zur Liste</Link>
+      </main>
+    );
+
+  return (
+    <main className="mx-auto max-w-xl space-y-3 p-6">
+      <Link href="/" className="text-sm underline">← Zurück</Link>
+      <h1 className="text-xl font-bold">{v.name}</h1>
+      <dl className="space-y-1 text-sm">
+        <div><dt className="font-medium">Anbieter</dt><dd>{v.anbieter}</dd></div>
+        <div><dt className="font-medium">Wert</dt><dd>{formatEuro(v.wertCents)}</dd></div>
+        <div><dt className="font-medium">Rest</dt><dd>{formatEuro(v.restCents)}</dd></div>
+        <div><dt className="font-medium">Status</dt><dd>{v.status}</dd></div>
+        {v.ablaufdatum && <div><dt className="font-medium">Ablaufdatum</dt><dd>{new Date(v.ablaufdatum).toLocaleDateString("de-DE")}</dd></div>}
+        {v.codeText && <div><dt className="font-medium">Code</dt><dd>{v.codeText}</dd></div>}
+        {v.kategorie && <div><dt className="font-medium">Kategorie</dt><dd>{v.kategorie}</dd></div>}
+        {v.notiz && <div><dt className="font-medium">Notiz</dt><dd>{v.notiz}</dd></div>}
+      </dl>
+      {v.status !== "eingeloest" && (
+        <button onClick={redeem} className="rounded bg-black px-4 py-2 text-white">
+          Einlösen
+        </button>
+      )}
+    </main>
+  );
+}