feat: add prototype-based annotation view with single-choice rating

src/app/actions/annotations.ts

@@ -10,8 +10,7 @@ import { headers } from 'next/headers';
 import type { AnnotationEntry } from '@/lib/dialects';
 
 /**
- * Returns shuffled unannotated entries for the given dataset and authenticated user.
- * Consecutive entries will never share the same externalId.
+ * Returns unannotated entries for the given dataset and authenticated user.
  */
 export async function getAnnotationEntries(datasetId: number): Promise<AnnotationEntry[]> {
   const session = await auth.api.getSession({ headers: await headers() });
@@ -48,7 +47,7 @@ export async function getAnnotationEntries(datasetId: number): Promise<Annotatio
     datasetId: e.datasetId,
   }));
 
-  return shuffleWithConstraint(mapped);
+  return mapped;
 }
 
 /**
@@ -105,31 +104,3 @@ export async function getAnnotationProgress(
   return { total: allEntries.length, done: annotated.length };
 }
 
-// ---------------------------------------------------------------------------
-// Helpers
-// ---------------------------------------------------------------------------
-
-/** Fisher-Yates shuffle with a greedy fix for consecutive same externalId. */
-function shuffleWithConstraint(entries: AnnotationEntry[]): AnnotationEntry[] {
-  if (entries.length <= 1) return entries;
-
-  const arr = [...entries];
-  for (let i = arr.length - 1; i > 0; i--) {
-    const j = Math.floor(Math.random() * (i + 1));
-    [arr[i], arr[j]] = [arr[j], arr[i]];
-  }
-
-  // Single-pass greedy fix
-  for (let i = 1; i < arr.length; i++) {
-    if (arr[i].externalId === arr[i - 1].externalId) {
-      for (let j = i + 1; j < arr.length; j++) {
-        if (arr[j].externalId !== arr[i - 1].externalId) {
-          [arr[i], arr[j]] = [arr[j], arr[i]];
-          break;
-        }
-      }
-    }
-  }
-
-  return arr;
-}

src/app/annotate/[datasetId]/[prototype]/page.tsx

@@ -0,0 +1,57 @@
+import { redirect, notFound } from 'next/navigation';
+import { headers } from 'next/headers';
+import Link from 'next/link';
+import { auth } from '@/lib/auth';
+import { getAnnotationEntries } from '@/app/actions/annotations';
+import SingleChoiceView from '@/components/AnnotationViews/SingleChoiceView';
+
+interface Props {
+  params: Promise<{ datasetId: string; prototype: string }>;
+}
+
+export default async function AnnotatePage({ params }: Props) {
+  const session = await auth.api.getSession({ headers: await headers() });
+  if (!session) redirect('/user/sign-in');
+
+  const { datasetId: datasetIdStr, prototype } = await params;
+  const datasetId = parseInt(datasetIdStr, 10);
+
+  if (isNaN(datasetId)) {
+    return (
+      <div className="max-w-xl mx-auto py-16 text-center">
+        <p className="text-gray-600">Ungültige Dataset-ID.</p>
+        <Link href="/" className="text-blue-600 hover:underline mt-4 inline-block">
+          ← Startseite
+        </Link>
+      </div>
+    );
+  }
+
+  if (prototype !== 'single-choice') {
+    notFound();
+  }
+
+  const entries = await getAnnotationEntries(datasetId);
+
+  if (entries.length === 0) {
+    return (
+      <div className="max-w-xl mx-auto py-20 text-center">
+        <div className="text-5xl mb-4">✓</div>
+        <h1 className="text-2xl font-bold text-green-600 mb-3">
+          Alle Samples bewertet!
+        </h1>
+        <p className="text-gray-600 mb-8">
+          Sie haben alle Samples in diesem Dataset bereits bewertet. Danke für Ihre Mitarbeit!
+        </p>
+        <Link
+          href="/"
+          className="px-6 py-3 bg-blue-600 hover:bg-blue-700 text-white font-semibold rounded-lg transition-colors"
+        >
+          Zurück zur Startseite
+        </Link>
+      </div>
+    );
+  }
+
+  return <SingleChoiceView entries={entries} datasetId={datasetId} />;
+}

src/app/annotate/[datasetId]/page.tsx

@@ -2,52 +2,52 @@ import { redirect } from 'next/navigation';
 import { headers } from 'next/headers';
 import Link from 'next/link';
 import { auth } from '@/lib/auth';
-import { getAnnotationEntries } from '@/app/actions/annotations';
-import AnnotationView from '@/components/AnnotationView';
+
+const PROTOTYPES = [
+  {
+    id: 'single-choice',
+    name: 'Single Choice',
+    description: 'Bewerten Sie jedes Sample auf einer Skala von 1–5.',
+  },
+];
 
 interface Props {
   params: Promise<{ datasetId: string }>;
 }
 
-export default async function AnnotatePage({ params }: Props) {
+export default async function PrototypeSelectionPage({ params }: Props) {
   const session = await auth.api.getSession({ headers: await headers() });
   if (!session) redirect('/user/sign-in');
 
-  const { datasetId: datasetIdStr } = await params;
-  const datasetId = parseInt(datasetIdStr, 10);
+  const { datasetId } = await params;
 
-  if (isNaN(datasetId)) {
-    return (
-      <div className="max-w-xl mx-auto py-16 text-center">
-        <p className="text-gray-600">Ungültige Dataset-ID.</p>
-        <Link href="/" className="text-blue-600 hover:underline mt-4 inline-block">
-          ← Startseite
-        </Link>
+  return (
+    <div className="max-w-2xl mx-auto py-8">
+      <Link href="/" className="text-sm text-gray-500 hover:text-gray-700 mb-6 inline-block">
+        ← Zurück zur Startseite
+      </Link>
+      <h1 className="text-2xl font-bold text-gray-800 mb-2">Prototyp auswählen</h1>
+      <p className="text-gray-500 mb-8">
+        Wählen Sie einen Annotationsprototyp aus, um mit der Bewertung zu beginnen.
+      </p>
+
+      <div className="flex flex-col gap-4">
+        {PROTOTYPES.map((proto) => (
+          <Link
+            key={proto.id}
+            href={`/annotate/${datasetId}/${proto.id}`}
+            className="bg-white border border-gray-200 rounded-xl p-5 shadow-sm hover:border-blue-300 hover:shadow-md transition-all"
+          >
+            <div className="flex items-center justify-between">
+              <div>
+                <h2 className="font-semibold text-gray-800">{proto.name}</h2>
+                <p className="text-sm text-gray-500 mt-0.5">{proto.description}</p>
+              </div>
+              <span className="text-gray-400 text-lg">→</span>
+            </div>
+          </Link>
+        ))}
       </div>
-    );
-  }
-
-  const entries = await getAnnotationEntries(datasetId);
-
-  if (entries.length === 0) {
-    return (
-      <div className="max-w-xl mx-auto py-20 text-center">
-        <div className="text-5xl mb-4">✓</div>
-        <h1 className="text-2xl font-bold text-green-600 mb-3">
-          Alle Samples bewertet!
-        </h1>
-        <p className="text-gray-600 mb-8">
-          Sie haben alle Samples in diesem Dataset bereits bewertet. Danke für Ihre Mitarbeit!
-        </p>
-        <Link
-          href="/"
-          className="px-6 py-3 bg-blue-600 hover:bg-blue-700 text-white font-semibold rounded-lg transition-colors"
-        >
-          Zurück zur Startseite
-        </Link>
-      </div>
-    );
-  }
-
-  return <AnnotationView entries={entries} datasetId={datasetId} />;
+    </div>
+  );
 }