package org.apache.turbine.services.template.mapper;

 /*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache 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.apache.org/licenses/LICENSE-2.0

  *

  * 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.

  */

 import java.util.ArrayList;

 import java.util.Arrays;

 import java.util.List;

 import org.apache.commons.lang.StringUtils;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.apache.turbine.services.TurbineServices;

 import org.apache.turbine.services.template.TemplateEngineService;

 import org.apache.turbine.services.template.TemplateService;

 /**

  * This mapper is responsible for the lookup of templates for the Layout

  * It tries to look in various packages for a match:

  *

  * 1. about,directions,Driving.vm      <- exact match

  * 2. about,directions,Default.vm      <- package match, Default name

  * 3. about,Default.vm                 <- stepping up in the hierarchy

  * 4. Default.vm                       <- The name configured as default.layout.template

  *                                        in the corresponding Templating Engine

  *

  * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>

  * @version $Id: LayoutTemplateMapper.java 1723699 2016-01-08 11:29:21Z tv $

  */

 public class LayoutTemplateMapper

     extends BaseTemplateMapper

     implements Mapper

 {

     /** Logging */

     private static Log log = LogFactory.getLog(LayoutTemplateMapper.class);

     /**

      * Default C'tor. If you use this C'tor, you must use

      * the bean setter to set the various properties needed for

      * this mapper before first usage.

      */

     public LayoutTemplateMapper()

     {

             // empty

     }

     /**

      * Look for a given Template, then try the

      * defaults until we hit the root.

      *

      * @param template The template name.

      * @return The parsed module name.

      */

     @Override

     public String doMapping(String template)

     {

         log.debug("doMapping(" + template + ")");

         // Copy our elements into an array

         List<String> components

             = new ArrayList<String>(Arrays.asList(StringUtils.split(

                                               template,

                                               String.valueOf(TemplateService.TEMPLATE_PARTS_SEPARATOR))));

         int componentSize = components.size() - 1 ;

         // This method never gets an empty string passed.

         // So this is never < 0

         String templateName = components.get(componentSize);

         components.remove(componentSize--);

         log.debug("templateName is " + templateName);

         // Last element decides, which template Service to use...

         TemplateService templateService = (TemplateService)TurbineServices.getInstance().getService(TemplateService.SERVICE_NAME);

         TemplateEngineService tes = templateService.getTemplateEngineService(templateName);

         if (tes == null)

         {

             return null;

         }

         // We're, after all, a Layout Template Mapper...

         String defaultName = templateService.getDefaultLayoutTemplateName(templateName);

         // This is an optimization. If the name we're looking for is

         // already the default name for the template, don't do a "first run"

         // which looks for an exact match.

         boolean firstRun = !templateName.equals(defaultName);

         for(;;)

         {

             String templatePackage = StringUtils.join(components.iterator(), String.valueOf(separator));

             log.debug("templatePackage is now: " + templatePackage);

             StringBuilder testName = new StringBuilder();

             if (!components.isEmpty())

             {

                 testName.append(templatePackage);

                 testName.append(separator);

             }

             testName.append((firstRun)

                 ? templateName

                 : defaultName);

             // But the Templating service must look for the name with prefix

             StringBuilder templatePath = new StringBuilder();

             if (StringUtils.isNotEmpty(prefix))

             {

                 templatePath.append(prefix);

                 templatePath.append(separator);

             }

             templatePath.append(testName);

             log.debug("Looking for " + templatePath);

             if (tes.templateExists(templatePath.toString()))

             {

                 log.debug("Found it, returning " + testName);

                 return testName.toString();

             }

             if (firstRun)

             {

                 firstRun = false;

             }

             else

             {

                 // We're no longer on the first Run (so we

                 // already tested the "Default" template)

                 // and the package is empty (we've hit the

                 // root. So we now break the endless loop.

                 if (components.isEmpty())

                 {

                     break; // for(;;)

                 }

                 // We still have components. Remove the

                 // last one and go through the loop again.

                 components.remove(componentSize--);

             }

         }

         log.debug("Returning default");

         return getDefaultName(template);

     }

 }