package sk.stuba.fiit.perconik.core.persistence.data;

import javax.annotation.Nullable;

import sk.stuba.fiit.perconik.core.Listeners;
import sk.stuba.fiit.perconik.core.Registrable;
import sk.stuba.fiit.perconik.core.persistence.ListenerRegistration;
import sk.stuba.fiit.perconik.core.services.Services;

/**
 * An abstract implementation of the {@link ListenerRegistration} interface.
 * Implemented predicates like the current registration status are obtained
 * directly from the core using the underlying listener or listener's data.
 *
 * @author Pavol Zbell
 * @since 1.0
 */
public abstract class AbstractListenerRegistration extends AbstractAnnotableRegistration implements ListenerRegistration {
  /**
   * Constructor for use by subclasses.
   */
  protected AbstractListenerRegistration() {}

  @Override
  final Registrable registrable() {
    return this.getListener();
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public final boolean equals(@Nullable final Object o) {
    if (this == o) {
      return true;
    }

    if (!(o instanceof ListenerRegistration)) {
      return false;
    }

    ListenerRegistration other = (ListenerRegistration) o;

    return this.getListenerClass() == other.getListenerClass();
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public final int hashCode() {
    return 31 * this.getListenerClass().hashCode();
  }

  @Override
  public final String toString() {
    return Utilities.toString(this);
  }

  /**
   * {@inheritDoc}
   */
  public final boolean isRegistered() {
    return Listeners.isRegistered(this.getListener());
  }

  /**
   * {@inheritDoc}
   */
  public final boolean isProvided() {
    return Services.getListenerService().getListenerProvider().classes().contains(this.getListenerClass());
  }
}