/**
    * 2007, Digitalis Informatica. All rights reserved. Distribuicao e Gestao de Informatica, Lda. Estrada de Paco de Arcos
    * num.9 - Piso -1 2780-666 Paco de Arcos Telefone: (351) 21 4408990 Fax: (351) 21 4408999 http://www.digitalis.pt
    */
   
   package pt.digitalis.dif.codegen.templates;
   
   import java.util.List;
   
  import pt.digitalis.dif.controller.ExceptionHandlers;
  import pt.digitalis.dif.controller.http.HTTPConstants;
  import pt.digitalis.dif.controller.interfaces.IDIFContext;
  import pt.digitalis.dif.controller.interfaces.IDispatcherErrorHandler;
  import pt.digitalis.dif.dem.CallbackType;
  import pt.digitalis.dif.dem.interfaces.IProvider;
  import pt.digitalis.dif.dem.interfaces.IStageInstance;
  import pt.digitalis.dif.dem.managers.IDEMManager;
  import pt.digitalis.dif.dem.managers.IMessageManager;
  import pt.digitalis.dif.dem.managers.IParameterManager;
  import pt.digitalis.dif.dem.managers.IRegistrationManager;
  import pt.digitalis.dif.dem.objects.EventType;
  import pt.digitalis.dif.dem.objects.ViewObject;
  import pt.digitalis.dif.dem.objects.parameters.IParameters;
  import pt.digitalis.dif.dem.objects.parameters.ParameterScope;
  import pt.digitalis.dif.exception.InternalFrameworkException;
  import pt.digitalis.dif.ioc.DIFIoCRegistry;
  import pt.digitalis.dif.utils.extensions.document.IDocumentRepositoryManager;
  import pt.digitalis.dif.utils.logging.DIFLogger;
  import pt.digitalis.utils.common.StringUtils;
  
  /**
   * Resources used by the DEM Entity templates on the code generation.
   * 
   * @author Pedro Viegas <a href="mailto:pviegas@digitalis.pt">pviegas@digitalis.pt</a>
   * @author Rodrigo Gonçalves <a href="mailto:rgoncalves@digitalis.pt">rgoncalves@digitalis.pt</a>
   * @created Nov 6, 2007
   */
  public final class TemplateResources {
  
      /*
       * Implementation Note: This class holds resources used by the DEM entity templates. Since copying from template
       * doesn't initialize properly the private attributes, the resources used by the enhanced entities were placed on
       * this class thus enabling the entities to access them as needed.
       */
  
      /** The DEM manager. */
      static private IDEMManager demManager = DIFIoCRegistry.getRegistry().getImplementation(IDEMManager.class);
  
      /** The document repository manager. */
      static private IDocumentRepositoryManager documentRepositoryManager = null;
  
      /** Singleton instance */
      static private TemplateResources instance = null;
  
      /** The message manager. */
      static private IMessageManager messageManager = DIFIoCRegistry.getRegistry().getImplementation(
              IMessageManager.class);
  
      /** The parameter manager */
      static private IParameterManager parameterManager = DIFIoCRegistry.getRegistry().getImplementation(
              IParameterManager.class);
  
      /** The registration manager. */
      static private IRegistrationManager registrationManager = DIFIoCRegistry.getRegistry().getImplementation(
              IRegistrationManager.class);
  
      /**
       * Returns a callback type
       * 
       * @param id
       *            the id of the call back to return
       * @return the registrationManager
       */
      static public CallbackType getCallBack(String id)
      {
          return CallbackType.valueOf(id);
      }
  
      /**
       * Returns the DEM manager.
       * 
       * @return the demManager
       */
      static public IDEMManager getDEMManager()
      {
          return TemplateResources.demManager;
      }
  
      /**
       * Inspector for the 'documentRepositoryManager' attribute.
       * 
       * @return the documentRepositoryManager value
       */
      public static IDocumentRepositoryManager getDocumentRepositoryManager()
      {
          if (documentRepositoryManager == null)
              documentRepositoryManager = DIFIoCRegistry.getRegistry()
                      .getImplementation(IDocumentRepositoryManager.class);
  
         return documentRepositoryManager;
     }
 
     /**
      * Returns an event type
      * 
      * @param id
      *            the id of the event to return
      * @return the registrationManager
      */
     static public EventType getEventType(String id)
     {
         return EventType.valueOf(id);
     }
 
     /**
      * @return the singleton instance
      */
     static public TemplateResources getInstance()
     {
         if (instance == null)
             instance = new TemplateResources();
 
         return instance;
     }
 
     /**
      * Returns an IoC implementation
      * 
      * @param clazz
      *            the class that defines the implementation interface
      * @return the implementation
      */
     static public Object getIoCImplementation(String clazz)
     {
         try
         {
             return DIFIoCRegistry.getRegistry().getImplementation(Class.forName(clazz));
         }
         catch (ClassNotFoundException e)
         {
             return null;
         }
     }
 
     /**
      * Returns the message manager.
      * 
      * @return the messageManager
      */
     static public IMessageManager getMessageManager()
     {
         return TemplateResources.messageManager;
     }
 
     /**
      * Returns the parameter manager.
      * 
      * @return the parameterManager
      */
     static public IParameterManager getParameterManager()
     {
         return TemplateResources.parameterManager;
     }
 
     /**
      * Returns the parameter scope
      * 
      * @param scope
      *            the scope as a param
      * @return the parameter scope
      */
     static public ParameterScope getParameterScope(String scope)
     {
         return ParameterScope.valueOf(scope);
     }
 
     /**
      * Returns a IParameters instance Development note: This is a workaround for a Javassist bug. Could not have this
      * line of the generated code.
      * 
      * @param stage
      *            the stage to get the parameters for
      * @return the registrationManager
      */
     static public IParameters getParametersInstance(IStageInstance stage)
     {
         IParameters parameters = DIFIoCRegistry.getRegistry().getImplementation(IParameters.class);
         parameters.initialize(stage);
 
         return parameters;
     }
 
     /**
      * Returns the providers as a List of {@link IProvider}
      * 
      * @return the registrationManager
      */
     static public List<IProvider> getProvidersAsList()
     {
         return java.util.Arrays.asList(getDEMManager().getProviders().values().toArray(new IProvider[] {null}));
     }
 
     /**
      * Returns the registration manager.
      * 
      * @return the registrationManager
      */
     static public IRegistrationManager getRegistrationManager()
     {
         return TemplateResources.registrationManager;
     }
 
     /**
      * returns a given parameter form the request
      * 
      * @param context
      *            the current context
      * @param id
      *            the Id of the desired parameter
      * @return the parameter value as string
      */
     static public String getRequestParameter(IDIFContext context, String id)
     {
         if (context != null && context.getRequest() != null)
         {
             Object result = context.getRequest().getParameter(id.toLowerCase());
 
             if (result == null)
                 return null;
             else
                 return result.toString();
 
         }
         else
             return null;
     }
 
     /** Private constructor. Singleton implementation */
     private TemplateResources()
     {}
 
     /**
      * The stage execute logic
      * 
      * @param stageInstance
      * @param context
      * @return the view object to render the stage output in
      */
     public ViewObject stageExecute(IStageInstance stageInstance, IDIFContext context)
     {
         // Declare result variable
         ViewObject result = null;
 
         // Will determine if we should return the default view. According to the event of default execution handler.
         boolean returnDefaultView = true;
 
         try
         {
             // FIXME: Refactor so that the AbstractDIFDispatcher remains abstracted from the HTTP
             // implementation. Use generic EventHandlers, instead of formSubmit
             Object submitStage = context.getRequest().getParameter(HTTPConstants.FORM_SUBMIT_STAGE);
             Object submitForm = context.getRequest().getParameter(HTTPConstants.FORM_SUBMIT_NAME);
             Object submitFormValidationRequest = context.getRequest().getParameter(HTTPConstants.FORM_VALIDATION);
             boolean isFormValidationRequest = Boolean.parseBoolean(StringUtils.nvl(
                     StringUtils.toStringOrNull(submitFormValidationRequest), "false"));
 
             Object eventID = context.getRequest().getParameter(HTTPConstants.EVENT_ID);
 
             // If form submitted check if an event handler of validation type for it exists (must call it prior to the
             // submit itself)
             if (stageInstance.getID().equalsIgnoreCase((String) submitStage)
                     && stageInstance.hasValidationLogicForForm(StringUtils.toStringOrNull(submitForm)))
                 stageInstance.callExecuteOnEventMethod(context, EventType.FORM_VALIDATION, submitForm.toString());
 
             // If form submitted check if an event handler for it exists
             if (isFormValidationRequest && stageInstance.getID().equalsIgnoreCase((String) submitStage)
                     && stageInstance.hasValidationLogicForForm(StringUtils.toStringOrNull(submitForm)))
             {
                 // The validation function has already been called. No other action is needed
                 // Result can only be null here so no action is required
             }
             // If form submitted check if an event handler for it exists
             else if (stageInstance.getID().equalsIgnoreCase((String) submitStage)
                     && (stageInstance.getEventHandlers().get(EventType.FORM_SUBMIT).contains(submitForm)
                             || stageInstance.getEventHandlers().get(EventType.FORM_SUBMIT_SAVE_ACTION)
                                     .contains(submitForm) || stageInstance.getEventHandlers()
                             .get(EventType.FORM_SUBMIT_AJAX_REQUEST).contains(submitForm)))
             {
                 // Execute specific on submit event handler
                 if (context.getRequest().isAjaxMode())
                 {
                     result = stageInstance.callExecuteOnEventMethod(context, EventType.FORM_SUBMIT_AJAX_REQUEST,
                             submitForm.toString());
                     returnDefaultView = true;
                 }
                 else
                 {
                     result = stageInstance.callExecuteOnEventMethod(context, EventType.FORM_SUBMIT,
                             submitForm.toString());
                 }
             }
             else
             {
                 boolean resultProcessed = false;
 
                 if (eventID != null)
                 {
                     for (EventType type: stageInstance.getEventHandlers().keySet())
                     {
                         for (String currentEventID: stageInstance.getEventHandlers().get(type))
                         {
                             if (currentEventID.equalsIgnoreCase(eventID.toString()))
                             {
                                 // Execute specific on submit event handler
                                 DIFLogger.getLogger().debug("_CG_execute: " + stageInstance.getID());
                                 DIFLogger.getLogger().debug("Event: " + eventID + "(" + type + ")");
 
                                 result = stageInstance.callExecuteOnEventMethod(context, type, currentEventID);
                                 resultProcessed = true;
 
                                 returnDefaultView = returnDefaultView && (type != EventType.AJAX_REQUEST)
                                         && (type != EventType.DOCUMENT_TYPE);
 
                                 break;
                             }
                         }
 
                         if (resultProcessed)
                             break;
                     }
                 }
 
                 if (!resultProcessed)
                     // Execute normal business logic
                     result = stageInstance.callExecuteMethod(context);
             }
 
             // If execution was OK but no view was returned set the result as the default view
             if (result == null && returnDefaultView)
                 result = stageInstance.getDefaultView();
 
         }
         catch (Exception exception)
         {
             exception.printStackTrace();
             String exceptionType = exception.getClass().getCanonicalName();
 
             // If an exception was raised check if there's a redirection to trigger...
             // ...current stage error view...
             if (stageInstance.getInjectedErrorViews().size() != 0
                     && stageInstance.getInjectedErrorViews().containsKey(exceptionType))
             {
                 context.addStageResult(IDispatcherErrorHandler.EXCEPTION, exception);
                 result = stageInstance.getInjectedErrorViews().get(exceptionType);
 
             }
             // ...current stage error stage...
             else if (stageInstance.getInjectedErrorStages().size() != 0
                     && stageInstance.getInjectedErrorStages().containsKey(exceptionType))
             {
                 context.addStageResult(IDispatcherErrorHandler.EXCEPTION, exception);
                 context.redirectTo(stageInstance.getInjectedErrorStages().get(exceptionType));
 
             }
             // ...system wide exception handler stage...
             else if (ExceptionHandlers.hasHandler(exception))
             {
                 ExceptionHandlers.handleException(context, exception);
             }
             else
                 throw new RuntimeException(
                         "Unable to proceed! A business exception was raised and no error views or stages were"
                                 + " defined for redirection. Aborting... ", new InternalFrameworkException(exception,
                                 context));
         }
 
         return result;
     }
 }