/*
    * JaspertReports JSF Plugin Copyright (C) 2011 A. Alonso Dominguez
    *
    * This library is free software; you can redistribute it and/or modify it
    * under the terms of the GNU Lesser General Public License as published by
    * the Free Software Foundation; either version 2.1 of the License, or (at
    * your option) any later version. This library is distributed in the hope
    * that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
    * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   *
   * See the GNU Lesser General Public License for more details. You should have
   * received a copy of the GNU Lesser General Public License along with this
   * library; if not, write to the Free Software Foundation, Inc., 59 Temple
   * Place, Suite 330, Boston, MA 02111-1307 USA A.
   *
   * Alonso Dominguez
   * alonsoft@users.sf.net
   */
  package net.sf.jasperreports.jsf.resource;
  
  import java.io.File;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  
  import javax.faces.component.UIComponent;
  import javax.faces.context.FacesContext;
  
  import net.sf.jasperreports.jsf.Constants;
  import net.sf.jasperreports.jsf.component.UIReport;
  import net.sf.jasperreports.jsf.context.ExternalContextHelper;
  import net.sf.jasperreports.jsf.context.JRFacesContext;
  import net.sf.jasperreports.jsf.util.Util;
  
  import static org.apache.commons.io.FilenameUtils.*;
  
  /**
   *
   * @author aalonsodominguez
   */
  public final class DefaultResourceResolver implements ResourceResolver {
  
  	private static final Logger logger = Logger.getLogger(
  			DefaultResourceResolver.class.getPackage().getName(),
  			Constants.LOG_MESSAGES_BUNDLE);
  	
      public Resource resolveResource(FacesContext context, UIComponent component,
              String name) {
          if (name == null || name.length() == 0) {
              throw new IllegalArgumentException(
                      "Resource name must be provided.");
          }
  
          Resource resource = null;
          try {
              final URL url = new URL(name);
              resource = new URLResource(url);
          } catch (MalformedURLException e) {
              final ClassLoader loader = Util.getClassLoader(this);
              if (name.startsWith(ClasspathResource.PREFIX)) {
                  resource = new ClasspathResource(name, loader);
              } else if (name.startsWith("/")) {
                  resource = new ContextResource(name);
              } else if (loader.getResource(name) != null) {
                  resource = new ClasspathResource(name, loader);
              } else {
                  resource = resolveRelative(context, component, name);
              }
          }
  
          // If at this point 'resource' is null then the resource couldn't
          // be resolved by this ResourceResolver implementation
          return resource;
      }
  
      private Resource resolveRelative(FacesContext context, 
              UIComponent component, String name) {
      	if (logger.isLoggable(Level.FINE)) {
      		logger.log(Level.FINE, "JRJSF_0039", name);
      	}
      	
          Resource resource = null;
          JRFacesContext jrContext = JRFacesContext.getInstance(context);
          ExternalContextHelper helper =
                  jrContext.getExternalContextHelper(context);
          String rootPath = null;
  
          if ((component != null) && (component instanceof UIReport)) {
              // If caller component is a report-based component then try to
              // resolve the resource relative to the report resource (if given).
  
              Object value = ((UIReport) component).getValue();
              if (value != null && (value instanceof String)) {
              	String valueStr = (String) value;
              	if (!valueStr.equals(name)) {
              		// If the resource we are trying to resolve is the one
              		// established in the report itself then resolve it
              		// using the current viewRoot
 	                rootPath = helper.getResourceRealPath(
 	                    context.getExternalContext(),
 	                    "/" + getPath((String) value));
             	}
             }
         }
         
         if (rootPath == null) {
             // If caller component is not a report-based component or
             // there is not any component at all, resolve the resource
             // name relative to the current view.
 
             String viewId = context.getViewRoot().getViewId();
             rootPath = helper.getResourceRealPath(
                     context.getExternalContext(), "/" + getPath(viewId));
         }
 
         if (rootPath != null) {
             String resourceFileName = rootPath + File.separator + name;
             File resourceFile = new File(normalize(resourceFileName));
             if (resourceFile.exists()) {
                 resource = new FileResource(resourceFile);
             }
         }
 
         return resource;
     }
 
 }