[keycloak-user] IdP selection based on email address

Hello, We are using keycloak with multiple IdP from our customers. Because we don't want to offer a list of Idp (customer A can't use the idp of customer B), I would like to prompt the user for the email address first and decide then to redirect to a specific IdP based on the domain as an example. Does somebody here can advise me on the greatest way to implement this behavior? My first thought was to use a custom flow with a script, but I can't find how to specify the idp to use using script. Best regards, Yann Jouanin