Fix ModUser logic.

src/requests/admin.cr

@@ -50,8 +50,8 @@ class AuthD::Request
 	AuthD.requests << AddUser
 
 	IPC::JSON.message ModUser, 5 do
-		property user       : UserID
-		property admin      : Bool    = false
+		property user       : UserID | Nil = nil
+		property admin      : Bool?   = nil
 		property password   : String? = nil
 		property email      : String? = nil
 		property phone      : String? = nil
@@ -63,14 +63,18 @@ class AuthD::Request
 			logged_user = authd.get_logged_user_full? fd
 			return Response::Error.new "you must be logged" if logged_user.nil?
 
-			user = authd.user? @user
+			user = if u = @user
+				logged_user.assert_permission("authd", "*", User::PermissionLevel::Edit)
+				authd.user? u
+			else
+				logged_user
+			end
 			return Response::Error.new "user not found" if user.nil?
 
-			# Only an admin can uprank someone.
-			if @admin
+			# Only an admin can uprank or downrank someone.
+			if admin = @admin
 				logged_user.assert_permission("authd", "*", User::PermissionLevel::Admin)
-			else
-				logged_user.assert_permission("authd", "*", User::PermissionLevel::Edit)
+				user.admin = admin
 			end
 
 			@password.try do |s|