bearbeiten Button für admin angepasst, zusage funktion auch hinzugefügt

app/main.py

@@ -108,6 +108,17 @@ def ensure_schema():
             created_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP
         )
         """,
+        """
+        CREATE TABLE IF NOT EXISTS concert_attendance (
+            concert_id INTEGER NOT NULL REFERENCES concerts(id) ON DELETE CASCADE,
+            user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
+            status VARCHAR(20) NOT NULL CHECK (
+                status IN ('attending', 'maybe', 'ticket_search')
+            ),
+            updated_at TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+            PRIMARY KEY (concert_id, user_id)
+        )
+        """,
     ]
 
     with get_db_connection() as connection:
@@ -1090,6 +1101,22 @@ def concert_detail(request: Request, concert_id: int):
             )
             photo_rows = cursor.fetchall()
 
+            cursor.execute(
+                """
+                SELECT
+                    concert_attendance.user_id,
+                    concert_attendance.status,
+                    users.display_name,
+                    users.username
+                FROM concert_attendance
+                JOIN users ON users.id = concert_attendance.user_id
+                WHERE concert_attendance.concert_id = %s
+                ORDER BY users.display_name NULLS LAST, users.username
+                """,
+                (concert_id,),
+            )
+            attendance_rows = cursor.fetchall()
+
     comments = [
         {
             "id": row[0],
@@ -1110,6 +1137,20 @@ def concert_detail(request: Request, concert_id: int):
         for row in photo_rows
     ]
 
+    attendance = [
+        {
+            "user_id": row[0],
+            "status": row[1],
+            "name": row[2] or row[3],
+        }
+        for row in attendance_rows
+    ]
+    attending_users = [item for item in attendance if item["status"] == "attending"]
+    current_attendance = next(
+        (item["status"] for item in attendance if item["user_id"] == user["id"]),
+        None,
+    )
+
     template = templates.get_template("concert_detail.html")
     return template.render(
         user=user,
@@ -1118,6 +1159,9 @@ def concert_detail(request: Request, concert_id: int):
         photos=photos,
         can_edit=can_edit_concert(user, concert),
         can_delete=can_delete_concert(user, concert),
+        current_attendance=current_attendance,
+        attending_users=attending_users,
+        attending_count=len(attending_users),
     )
 
 
@@ -1404,6 +1448,39 @@ def delete_concert(request: Request, concert_id: int):
     return RedirectResponse("/", status_code=303)
 
 
+@app.post("/concerts/{concert_id}/attendance")
+def set_attendance(
+    request: Request,
+    concert_id: int,
+    status: str = Form(...),
+):
+    user = get_current_user(request)
+
+    if not user:
+        return login_redirect(f"/concerts/{concert_id}")
+    if status not in {"attending", "maybe", "ticket_search"}:
+        return HTMLResponse("<h1>Ungültige Auswahl</h1>", status_code=400)
+    if not load_concert(concert_id):
+        return HTMLResponse("<h1>Konzert nicht gefunden</h1>", status_code=404)
+
+    with get_db_connection() as connection:
+        with connection.cursor() as cursor:
+            cursor.execute(
+                """
+                INSERT INTO concert_attendance (concert_id, user_id, status)
+                VALUES (%s, %s, %s)
+                ON CONFLICT (concert_id, user_id)
+                DO UPDATE SET
+                    status = EXCLUDED.status,
+                    updated_at = CURRENT_TIMESTAMP
+                """,
+                (concert_id, user["id"], status),
+            )
+        connection.commit()
+
+    return RedirectResponse(f"/concerts/{concert_id}#attendance", status_code=303)
+
+
 @app.post("/concerts/{concert_id}/comments")
 def add_comment(
     request: Request,