package pt.digitalis.dif.dem.managers.impl;
   
   import java.util.HashMap;
   import java.util.Map;
   
   import pt.digitalis.dif.dem.DEMRegistryImpl;
   import pt.digitalis.dif.dem.Entity;
   import pt.digitalis.dif.dem.interfaces.IApplication;
   import pt.digitalis.dif.dem.interfaces.IEntity;
  import pt.digitalis.dif.dem.interfaces.IProvider;
  import pt.digitalis.dif.dem.interfaces.IService;
  import pt.digitalis.dif.dem.interfaces.IStage;
  import pt.digitalis.dif.dem.managers.IDEMManager;
  
  /**
   * This class manages the DEM entities, providing the connections between the elements to the CodeGen module. TODO: Do
   * performance tests to determine if the getters that search sequentially the Maps are too slow. One could keep an index
   * of IDs for each entity and gather by direct id searches the dependent entities we need. Since this will be seldom
   * used I think the effort is unnecessary.
   * 
   * @author Rodrigo Gonçalves <a href="mailto:rgoncalves@digitalis.pt">rgoncalves@digitalis.pt</a>
   * @author Pedro Viegas <a href="mailto:pviegas@digitalis.pt">pviegas@digitalis.pt</a>
   * @created 2007/06/01
   */
  public class DEMManagerImpl implements IDEMManager {
  
      // TODO: Try to see if one should cache the lists of entities so not to search all of them for ownership
  
      /**
       * @see pt.digitalis.dif.dem.managers.IDEMManager#getApplication(java.lang.String)
       */
      public IApplication getApplication(String applicationID)
      {
          return DEMRegistryImpl.getRegistry().getApplication(applicationID.toLowerCase());
      }
  
      /**
       * @see pt.digitalis.dif.dem.managers.IDEMManager#getApplications(pt.digitalis.dif.dem.interfaces.IProvider)
       */
      public Map<String, IApplication> getApplications(IProvider provider)
      {
          Map<String, IApplication> providerApplications = new HashMap<String, IApplication>();
  
          for (IApplication application: DEMRegistryImpl.getApplications().values())
          {
              // Prevent NPE in case an inexistent provider is referred
              if (application.getProvider() != null && application.getProvider().getID().equals(provider.getID()))
                  providerApplications.put(application.getID(), application);
          }
  
          return providerApplications;
      }
  
      /**
       * @see pt.digitalis.dif.dem.managers.IDEMManager#getDefaultProvider()
       */
      public IProvider getDefaultProvider()
      {
          return DEMRegistryImpl.getDefaultProvider();
      }
  
      /**
       * @see pt.digitalis.dif.dem.managers.IDEMManager#getEntity(pt.digitalis.dif.dem.Entity, java.lang.String)
       */
      public IEntity getEntity(Entity type, String entityID)
      {
          if (Entity.PROVIDER.equals(type))
              return getProvider(entityID);
  
          else if (Entity.APPLICATION.equals(type))
              return getApplication(entityID);
  
          else if (Entity.SERVICE.equals(type))
              return getService(entityID);
  
          else if (Entity.STAGE.equals(type))
              return getStage(entityID);
  
          else
              return null;
  
          // if (Entity.PROVIDER.equals(type))
          // return getProvider(entityID);
          //
          // else if (Entity.APPLICATION.equals(type))
          // return getApplication(entityID);
          //
          // else if (Entity.SERVICE.equals(type))
          // return getService(entityID);
          //
          // else if (Entity.STAGE.equals(type))
          // return getStage(entityID);
          //
          // else
          // return null;
      }
  
      /**
       * @see pt.digitalis.dif.dem.managers.IDEMManager#getProvider(java.lang.String)
      */
     public IProvider getProvider(String providerID)
     {
         return DEMRegistryImpl.getRegistry().getProvider(providerID.toLowerCase());
     }
 
     /**
      * @see pt.digitalis.dif.dem.managers.IDEMManager#getProviders()
      */
     public Map<String, IProvider> getProviders()
     {
         return DEMRegistryImpl.getProviders();
     }
 
     /**
      * @see pt.digitalis.dif.dem.managers.IDEMManager#getService(java.lang.String)
      */
     public IService getService(String serviceID)
     {
         return DEMRegistryImpl.getRegistry().getService(serviceID.toLowerCase());
     }
 
     /**
      * @see pt.digitalis.dif.dem.managers.IDEMManager#getServices(pt.digitalis.dif.dem.interfaces.IApplication)
      */
     public Map<String, IService> getServices(IApplication application)
     {
         Map<String, IService> applicationServices = new HashMap<String, IService>();
 
         for (IService service: DEMRegistryImpl.getServices().values())
         {
             // Prevent NPE in case an inexistent application is referred
             if (service.getApplication() != null && service.getApplication().getID().equals(application.getID()))
                 applicationServices.put(service.getID(), service);
         }
 
         return applicationServices;
     }
 
     /**
      * @see pt.digitalis.dif.dem.managers.IDEMManager#getStage(java.lang.String)
      */
     public IStage getStage(String stageID)
     {
         return DEMRegistryImpl.getRegistry().getStage(stageID.toLowerCase());
     }
 
     /**
      * @see pt.digitalis.dif.dem.managers.IDEMManager#getStages(pt.digitalis.dif.dem.interfaces.IService)
      */
     public Map<String, IStage> getStages(IService service)
     {
         Map<String, IStage> serviceStages = new HashMap<String, IStage>();
 
         for (IStage stage: DEMRegistryImpl.getStages().values())
         {
             // Prevent NPE in case an inexistent service is referred
             if (stage.getService() != null && stage.getService().getID().equals(service.getID()))
                 serviceStages.put(stage.getID(), stage);
         }
 
         return serviceStages;
     }
 }