added admin login

app/routes.py

@@ -257,11 +257,23 @@ def admin_login():
         if user and check_password(user, password):
             flask_login.login_user(user)
             current_app.logger.info(f"Admin login successful: {user_name}")
+
+            next_page = request.args.get("next")
+
+            if next_page:
+                session["next_url"] = next_page
+
             if not get_token():
-                set_cookie(user_name)
+                token = retrieve_token(user_name)
+                if not token:
+                    token = create_token(user_name)
+                return set_cookie(token)
+
+            return redirect(next_page or url_for("main.admin"))
         else:
             current_app.logger.warning(f"Failed admin login attempt: {user_name}")
             flash("Incorrect username or password. Please try again.", "error")
+
     return render_template("admin_login.html", form=form)