added access variable to exams soo we can distinguish private, public and confidential exams and also bugfixes and improvements

src/pages/classrooms/[id].tsx

@@ -159,6 +159,21 @@ export default function Home({ user, group, users, entity }: Props) {
       prev.includes(u.id) ? prev.filter((p) => p !== u.id) : [...prev, u.id]
     );
 
+  const toggleAllUsersInList = () =>
+    setSelectedUsers((prev) =>
+      prev.length === rows.length
+        ? []
+        : [
+            ...prev,
+            ...items.reduce((acc, i) => {
+              if (!prev.find((item) => item === i.id)) {
+                (acc as string[]).push(i.id);
+              }
+              return acc;
+            }, [] as string[]),
+          ]
+    );
+
   const removeParticipants = () => {
     if (selectedUsers.length === 0) return;
     if (!canRemoveParticipants) return;
@@ -428,6 +443,25 @@ export default function Home({ user, group, users, entity }: Props) {
                   {capitalize(type)}
                 </button>
               ))}
+              <button
+                onClick={() => {
+                  toggleAllUsersInList();
+                }}
+                disabled={rows.length === 0}
+                className={clsx(
+                  "bg-mti-purple-ultralight text-mti-purple px-4 py-2 rounded-full hover:text-white hover:bg-mti-purple-light",
+                  "transition duration-300 ease-in-out",
+                  "disabled:grayscale disabled:hover:bg-mti-purple-ultralight disabled:hover:text-mti-purple disabled:cursor-not-allowed",
+                  (isAdding ? nonParticipantUsers : group.participants)
+                    .length === selectedUsers.length &&
+                    "!bg-mti-purple-light !text-white"
+                )}
+              >
+                {"De/Select All"}
+              </button>
+              <span className="opacity-80">
+                {selectedUsers.length} selected
+              </span>
             </div>
           </section>