YggdrasilSession.java

package co.forsaken.projectindigo.session;

import java.io.IOException;
import java.net.URL;
import java.util.List;

import lombok.Data;
import lombok.Getter;
import lombok.NonNull;
import lombok.Setter;
import lombok.ToString;

import org.codehaus.jackson.annotate.JsonIgnoreProperties;

import co.forsaken.projectindigo.exceptions.AuthenticationException;
import co.forsaken.projectindigo.utils.HttpRequest;

@ToString(exclude = "password") public class YggdrasilSession implements Session {

  private static final URL               AUTH_URL    = HttpRequest.url("https://authserver.mojang.com/authenticate");
  private static final URL               REFRESH_URL = HttpRequest.url("https://authserver.mojang.com/refresh");

  private final String                   id;
  @Getter @Setter private List<Identity> identities;
  @Getter @Setter private String         password;
  @Getter @Setter private String         clientToken;
  @Getter @Setter private String         accessToken;

  public YggdrasilSession(@NonNull String id) {
    this.id = id;
  }

  public boolean isValid() {
    return accessToken != null;
  }

  public YggdrasilSession verify() throws AuthenticationException, InterruptedException, IOException {
    if (password != null && !password.isEmpty()) {
      authenticate();
    } else if (accessToken != null && clientToken != null) {
      refresh();
    } else {
      throw new AuthenticationException("Missing password/details", "Incomplete Credentials");
    }

    return this;
  }

  private void authenticate() throws IOException, InterruptedException, AuthenticationException {
    Object payload = new AuthenticatePayload(id, password);

    HttpRequest request = HttpRequest.post(AUTH_URL).bodyJson(payload).execute();

    if (request.getResponseCode() != 200) {
      ErrorResponse error = request.returnContent().asJson(ErrorResponse.class);
      throw new AuthenticationException(error.getErrorMessage(), error.getErrorMessage());
    } else {
      AuthenticateResponse response = request.returnContent().asJson(AuthenticateResponse.class);
      accessToken = response.getAccessToken();
      clientToken = response.getClientToken();
      identities = response.getAvailableProfiles();
      for (Identity identity : identities) {
        identity.setAccessToken(accessToken);
        identity.setClientToken(clientToken);
      }
    }
  }

  private void refresh() throws IOException, InterruptedException, AuthenticationException {
    Object payload = new RefreshPayload(accessToken, clientToken);

    HttpRequest request = HttpRequest.post(REFRESH_URL).bodyJson(payload).execute();

    if (request.getResponseCode() != 200) {
      ErrorResponse error = request.returnContent().asJson(ErrorResponse.class);
      throw new AuthenticationException(error.getErrorMessage(), error.getErrorMessage());
    } else {
      AuthenticateResponse response = request.returnContent().asJson(AuthenticateResponse.class);
      accessToken = response.getAccessToken();
      clientToken = response.getClientToken();
      identities = response.getAvailableProfiles();
      for (Identity identity : identities) {
        identity.setAccessToken(accessToken);
        identity.setClientToken(clientToken);
      }
    }
  }

  @Data private static class Agent {
    private final String name    = "Minecraft";
    private final int    version = 1;
  }

  @Data private static class AuthenticatePayload {
    private final Agent  agent = new Agent();
    private final String username;
    private final String password;
  }

  @Data @JsonIgnoreProperties(ignoreUnknown = true) private static class AuthenticateResponse {
    private String         accessToken;
    private String         clientToken;
    private List<Identity> availableProfiles;
    private Identity       selectedProfile;
  }

  @Data private static class RefreshPayload {
    private final String accessToken;
    private final String clientToken;
    private Identity     selectedProfile;
  }

  @Data private static class ErrorResponse {
    private String error;
    private String errorMessage;
    private String cause;
  }

}