/**
    * Copyright 2005-2014 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.rice.krad.uif.freemarker;
  
  import java.util.Collections;
  
  import org.apache.log4j.Logger;
  import org.kuali.rice.krad.uif.component.Component;
  import org.kuali.rice.krad.uif.lifecycle.ViewLifecycle;
  import org.kuali.rice.krad.uif.lifecycle.ViewLifecyclePhase;
  import org.kuali.rice.krad.uif.lifecycle.ViewLifecycleTaskBase;
  
  import freemarker.core.Environment;
  import freemarker.core.Macro;
  import freemarker.template.TemplateModel;
  
  /**
   * Perform actual rendering on a component during the lifecycle.
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class RenderComponentTask extends ViewLifecycleTaskBase<Component> {
  
      private static final Logger LOG = Logger.getLogger(RenderComponentTask.class);
  
      /**
       * Constructor.
       * 
       * @param phase The render phase for the component.
       */
      public RenderComponentTask() {
          super(Component.class);
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      protected void performLifecycleTask() {
          Component component = (Component) getElementState().getElement();
          if (!component.isRender() || component.getTemplate() == null) {
              return;
          }
          
          LifecycleRenderingContext renderingContext = ViewLifecycle.getRenderingContext();
          renderingContext.clearRenderingBuffer();
  
          renderingContext.importTemplate(component.getTemplate());
  
          for (String additionalTemplate : component.getAdditionalTemplates()) {
              renderingContext.importTemplate(additionalTemplate);
          }
  
          try {
              Environment env = renderingContext.getEnvironment();
  
              // Check for a single-arg macro, with the parameter name "component"
              // defer for parent rendering if not found
              Macro fmMacro = (Macro) env.getMainNamespace().get(component.getTemplateName());
  
              if (fmMacro == null) {
                  return;
              }
  
              String[] args = fmMacro.getArgumentNames();
              if (args == null || args.length != 1 || !component.getComponentTypeName().equals(args[0])) {
                  return;
              }
  
              FreeMarkerInlineRenderUtils.renderTemplate(env, component,
                      null, false, false, Collections.<String, TemplateModel> emptyMap());
  
              component.setRenderedHtmlOutput(renderingContext.getRenderedOutput());
              component.setSelfRendered(true);
          } catch (Throwable e) {
              if (ViewLifecycle.isStrict()) {
                  LOG.warn("Error rendering component during lifecycle phase " + getElementState()
                          + " falling back to higher level rendering", e);
              } else if (ViewLifecycle.isTrace() && LOG.isDebugEnabled()) {
                  LOG.debug("component rendering failed during lifecycle phase " + getElementState()
                          + " falling back to higher level rendering", e);
              }
          }
  
      }
  }