Override TypeScript controllers per theme

Based on the theme you are in, this article provides the necessary steps to override the TypeScript Controllers. You can override the Standard Controller with a controller that selects the controller for the theme you are in. Then, in the init method of the "contain and delegate" controller you can get the injector:

const injector = angular.element(document.body).injector();

and then say, if theme is InsiteCustom, use the injector to get the InsiteCustom version of the controller:

this.delegateToController = injector.get("InsiteCustomController"); 
else 
this.delegateToController = injector.get("InsiteStandardController");

In your "contain and delegate" controller you override all the standard methods and delegate the calls to the this.delegateToController methods.