package org.jtheque.core.managers.update.versions;

 import org.jtheque.core.managers.error.IErrorManager;

 import org.jtheque.core.managers.module.beans.ModuleContainer;

 import org.jtheque.core.managers.update.Updatable;

 import org.jtheque.utils.bean.Version;

 import org.jtheque.utils.collections.CollectionUtils;

 import javax.annotation.Resource;

 import java.util.Collection;

 import java.util.HashMap;

 import java.util.Map;

 /*

  * This file is part of JTheque.

  *

  * JTheque is free software: you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation, either version 3 of the License.

  *

  * JTheque 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 General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License

  * along with JTheque.  If not, see <http://www.gnu.org/licenses/>.

  */

 /**

  * A loader for the online version's file. 

  * 

  * @author Baptiste Wicht 

  */

 public final class VersionsLoader implements IVersionsLoader {

     private final Map<Object, VersionsFile> cache;

     private static final int CACHE_INITIAL_SIZE = 20;

     @Resource

     private IErrorManager errorManager;

     /**

      * Construct a new VersionsLoader.

      */

     public VersionsLoader() {

         super();

         cache = new HashMap<Object, VersionsFile>(CACHE_INITIAL_SIZE);

     }

     @Override

     public Version getVersion(Object object) {

         if (isModule(object)) {

             return new Version(((ModuleContainer) object).getInfos().version());

         } else if (isUpdatable(object)) {

             return ((Updatable) object).getVersion();

         }

         return null;

     }

     /**

      * Test if the object is a module.

      *

      * @param object The object to test.

      * @return true if the object is a module else false.

      */

     private static boolean isModule(Object object) {

         return object instanceof ModuleContainer;

     }

     /**

      * Test if the object is an updatable.

      *

      * @param object The object to test.

      * @return true if the object is an updatable else false.

      */

     private static boolean isUpdatable(Object object) {

         return object instanceof Updatable;

     }

     @Override

     public Collection<Version> getVersions(Object object) {

         VersionsFile file = getVersionsFile(object);

         return file == null ? CollectionUtils.<Version>emptyList() : CollectionUtils.expand(file.getVersions(), new VersionExpander());

     }

     @Override

     public Collection<OnlineVersion> getOnlineVersions(Object object) {

         return getVersionsFile(object).getVersions();

     }

     @Override

     public OnlineVersion getOnlineVersion(Version version, Object object) {

         for (OnlineVersion v : getOnlineVersions(object)) {

             if (v.getVersion().equals(version)) {

                 return v;

             }

         }

         return null;

     }

     @Override

     public InstallVersion getInstallVersion(String versionFileURL) {

         return new VersionsFileReader().read(versionFileURL).getInstallVersion();

     }

     @Override

     public Version getMostRecentVersion(Object object) {

         return getVersionsFile(object).getMostRecentVersion().getVersion();

     }

     /**

      * Return the version's file of the object.

      *

      * @param object The object to get the version's file.

      * @return The version's file of the module.

      */

     private VersionsFile getVersionsFile(Object object) {

         if (!cache.containsKey(object)) {

             cache.put(object, new VersionsFileReader().read(object));

             if (!cache.containsKey(object)) {

                 errorManager.addInternationalizedError("error.update.internet");

             }

         }

         return cache.get(object);

     }

 }