Combining Spring Security and Active Directory with JWT-Tokens - spring-boot

Question

I am currently working on building an Angular2-Application accessing a Spring Boot backend server for authentication and editing database data via REST-APIs. My current basic configuration to authenticate against our Active Directory looks like this:
#Override
protected void configure(HttpSecurity http) throws Exception {
http.authorizeRequests().anyRequest().authenticated().and().formLogin();
}
#Override
protected void configure(AuthenticationManagerBuilder authManagerBuilder) throws Exception {
authManagerBuilder.authenticationProvider(activeDirectoryLdapAuthenticationProvider()).userDetailsService(userDetailsService());
}
#Bean
public AuthenticationManager authenticationManager() {
return new ProviderManager(Arrays.asList(activeDirectoryLdapAuthenticationProvider()));
}
#Bean
public AuthenticationProvider activeDirectoryLdapAuthenticationProvider() {
ActiveDirectoryLdapAuthenticationProvider provider = new ActiveDirectoryLdapAuthenticationProvider(AD_DOMAIN, "ldap://" + AD_URL);
provider.setConvertSubErrorCodesToExceptions(true);
provider.setUseAuthenticationRequestCredentials(true);
return provider;
}
This works so that I can access the basic Spring Boot Actuator-APIs after logging in using the default Boot Login Form.
The next step would be intertwining the activeDirectoryLdapAuthenticationProvider with a token-based authentication solution that can be accessed by Angular2 - for that, i found an example repository on gitHub. It implements HMAC-based authentication using JWT tokens with a custom service structure.
My issue now comes in understanding how the components of Spring Security work together in the background. As i understand the example, it implements a customised version of UserDetailsService and its environment using the UserDTO and LoginDTO. These access a MockUser-Service for example user data - which is what I want to avoid, instead accessing our Active Directory to authenticate users.
I am still digging through the repository trying to understand every customised class implementation and if I can customise the AuthenticationService to fit my needs, but I feel relatively lost.
What I am looking for are experiences in combining these three components, or with Spring Security and how exactly the default UserDetailsService and AuthenticationProviders interact, so I can try and fit the ActiveDirectory-logic into the token solution.
Alternatively, is there a way to combine the default-LDAP/AD-Configuration with a default JWT-Solution such as this?