1 files changed, 48 insertions, 0 deletions
diff --git a/web/source/settings/lib/util/domain-permission.ts b/web/source/settings/lib/util/domain-permission.ts
new file mode 100644
index 000000000..b8dcbc8aa
--- /dev/null
+++ b/web/source/settings/lib/util/domain-permission.ts
@@ -0,0 +1,48 @@
+/*
+	GoToSocial
+	Copyright (C) GoToSocial Authors admin@gotosocial.org
+	SPDX-License-Identifier: AGPL-3.0-or-later
+
+	This program is free software: you can redistribute it and/or modify
+	it under the terms of the GNU Affero General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU Affero General Public License for more details.
+
+	You should have received a copy of the GNU Affero General Public License
+	along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+import isValidDomain from "is-valid-domain";
+import { get } from "psl";
+
+/**
+ * Check the input string to ensure it's a valid
+ * domain that doesn't include a wildcard ("*").
+ * @param domain 
+ * @returns 
+ */
+export function isValidDomainPermission(domain: string): boolean {
+	return isValidDomain(domain, {
+		wildcard: false,
+		allowUnicode: true
+	});
+}
+
+/**
+ * Checks a domain against the Public Suffix List <https://publicsuffix.org/> to see if we
+ * should suggest removing subdomain(s), since they're likely owned/ran by the same party.
+ * Eg., "social.example.com" suggests "example.com".
+ * @param domain 
+ * @returns 
+ */
+export function hasBetterScope(domain: string): string | undefined {
+	const lookup = get(domain);
+	if (lookup && lookup != domain) {
+		return lookup;
+	}
+}