initial commit

src/validation.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <string>
+
+namespace radiantwave::validation {
+
+// Returns true if `email` looks like a valid email address (single '@',
+// non-empty local and domain parts, no whitespace, domain has at least two
+// dot-separated labels).
+bool isValidEmail(const std::string& email);
+
+// Reduces `input` to uppercase alphanumeric characters, capped at 16.
+// Used for license key entry: the dash separators are re-inserted on display.
+std::string sanitizeLicenseKey(const std::string& input);
+
+// Formats a sanitized license key as four dash-separated groups of four
+// characters (XXXX-XXXX-XXXX-XXXX). Partial input yields partial output.
+std::string formatLicenseKey(const std::string& sanitized);
+
+} // namespace radiantwave::validation