Improve usability of users view (#5176)

* Improve usability of users view

Resolve #5173

* Fix query

* Follow review and fix

* Follow review

src/server/api/endpoints/admin/show-users.ts

@@ -49,6 +49,16 @@ export const meta = {
 				'remote',
 			]),
 			default: 'local'
+		},
+
+		username: {
+			validator: $.optional.str,
+			default: null
+		},
+
+		hostname: {
+			validator: $.optional.str,
+			default: null
 		}
 	}
 };
@@ -70,6 +80,14 @@ export default define(meta, async (ps, me) => {
 		case 'remote': query.andWhere('user.host IS NOT NULL'); break;
 	}
 
+	if (ps.username) {
+		query.andWhere('user.usernameLower like :username', { username: ps.username.toLowerCase() + '%' });
+	}
+
+	if (ps.hostname) {
+		query.andWhere('user.host like :hostname', { hostname: '%' + ps.hostname.toLowerCase() + '%' });
+	}
+
 	switch (ps.sort) {
 		case '+follower': query.orderBy('user.followersCount', 'DESC'); break;
 		case '-follower': query.orderBy('user.followersCount', 'ASC'); break;