Add enum MDUserAccountAction enumerating actions that accounts may be

put under externally

src/enums/MDUserAccountAction.php

@@ -0,0 +1,51 @@
+<?PHP
+/**
+ * Lists the types of external conditions put upon user accounts in the md context.
+ *
+ * @author Joshua Ramon Enslin <joshua@museum-digital.de>
+ */
+declare(strict_types = 1);
+
+/**
+ * Lists the types of external conditions put upon user accounts in the md context.
+ */
+enum MDUserAccountAction {
+
+    case none;
+    case email_reconfirmation_required;
+
+    /**
+     * Returns a value of this type based on a string.
+     *
+     * @param string $input Input to get a value from.
+     *
+     * @return MDUserAccountAction
+     */
+    public static function fromString(string $input):MDUserAccountAction {
+
+        return match($input) {
+            'none' => self::none,
+            'email_reconfirmation_required' => self::email_reconfirmation_required,
+            default => throw new MDpageParameterNotFromListException("Unknown user account action"),
+        };
+
+    }
+
+    /**
+     * Lists all available names.
+     *
+     * @return array<string>
+     */
+    public static function caseNames():array {
+
+        $output = [];
+
+        $cases = self::cases();
+        foreach ($cases as $case) {
+            $output[] = $case->name;
+        }
+
+        return $output;
+
+    }
+}