package at.gv.egiz.eaaf.core.impl.idp.builder;

import java.util.HashMap;
import java.util.Iterator;
import java.util.ServiceLoader;

import at.gv.egiz.eaaf.core.api.idp.IAttributeBuilder;
import lombok.extern.slf4j.Slf4j;

@Slf4j
public class AttributeBuilderRegistration {

  private static HashMap<String, IAttributeBuilder> builders;
  
  private static ServiceLoader<IAttributeBuilder> attributBuilderLoader =
      ServiceLoader.load(IAttributeBuilder.class);

  private static void addBuilder(final IAttributeBuilder builder) {
    builders.put(builder.getName(), builder);
  }

  static {
    builders = new HashMap<>();

    log.info("Loading protocol attribut-builder modules:");
    if (attributBuilderLoader != null) {
      final Iterator<IAttributeBuilder> moduleLoaderInterator = attributBuilderLoader.iterator();           
      while (moduleLoaderInterator.hasNext()) {
        try {
          final IAttributeBuilder modul = moduleLoaderInterator.next();
          log.info("Loading attribut-builder Modul Information: " + modul.getName());
          addBuilder(modul);

        } catch (final Throwable e) {
          log.error("Check configuration! " + "Some attribute-builder modul"
              + " is not a valid IAttributeBuilder", e);
        }
      }
    }

    log.info("Loading attribute-builder modules done");

  }
  
  /**
   * Get a specific attribute builder.
   *
   * @param name Attribute-builder friendly name
   *
   * @return Attribute-builder with this name or null if builder does not exists
   */
  public static IAttributeBuilder getAttributeBuilder(final String name) {
    return builders.get(name);

  }
  
  /**
   * Check if a specific attribute-builder is available.
   * 
   * @param name Attribute-builder friendly name
   * @return <code>true</code> if the builder is registered, otherwise <code>false</code>
   */
  public static boolean containsBuilder(final String name) {
    return builders.containsKey(name);
    
  }
  
  /**
   * Get all registered attribute-builder.
   * 
   * @return {@link Iterator} of all available builders
   */
  public static Iterator<IAttributeBuilder> getAllRegistratedBuilder() {
    return builders.values().iterator();
    
  }
  
  /**
   * Get the number of currently register attribute builders.
   * 
   * @return number of attribute builders
   */
  public static int getNumberOfRegisteredBuilders() {
    return builders.size();
    
  }
  
}