/*
    * 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.
   *
   */
  package org.apache.chemistry.opencmis.jcr;
  
  import org.apache.chemistry.opencmis.commons.exceptions.CmisConnectionException;
  import org.apache.chemistry.opencmis.commons.impl.server.AbstractServiceFactory;
  import org.apache.chemistry.opencmis.commons.server.CallContext;
  import org.apache.chemistry.opencmis.commons.server.CmisService;
  import org.apache.chemistry.opencmis.commons.server.CmisServiceFactory;
  import org.apache.chemistry.opencmis.jcr.impl.DefaultDocumentTypeHandler;
  import org.apache.chemistry.opencmis.jcr.impl.DefaultFolderTypeHandler;
  import org.apache.chemistry.opencmis.jcr.impl.DefaultUnversionedDocumentTypeHandler;
  import org.apache.chemistry.opencmis.jcr.type.JcrTypeHandlerManager;
  import org.apache.chemistry.opencmis.server.support.CmisServiceWrapper;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import javax.imageio.spi.ServiceRegistry;
  import javax.jcr.Repository;
  import javax.jcr.RepositoryException;
  import javax.jcr.RepositoryFactory;
  import java.math.BigInteger;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  
  /**
   * A {@link CmisServiceFactory} implementation which returns {@link JcrService} instances.  
   */
  public class JcrServiceFactory extends AbstractServiceFactory {
      private static final Log log = LogFactory.getLog(JcrServiceFactory.class);
  
      public static final String MOUNT_PATH_CONFIG = "mount-path";
      public static final String PREFIX_JCR_CONFIG = "jcr.";
  
      public static final BigInteger DEFAULT_MAX_ITEMS_TYPES = BigInteger.valueOf(50);
      public static final BigInteger DEFAULT_DEPTH_TYPES = BigInteger.valueOf(-1);
      public static final BigInteger DEFAULT_MAX_ITEMS_OBJECTS = BigInteger.valueOf(200);
      public static final BigInteger DEFAULT_DEPTH_OBJECTS = BigInteger.valueOf(10);
  
      private JcrTypeManager typeManager;
      private Map<String, String> jcrConfig;
      private String mountPath;
      private JcrRepository jcrRepository;
  
      @Override
      public void init(Map<String, String> parameters) {
          typeManager = createTypeManager();
          readConfiguration(parameters);
          PathManager pathManger = new PathManager(mountPath);
          JcrTypeHandlerManager typeHandlerManager = createTypeHandlerManager(pathManger, typeManager);
          jcrRepository = new JcrRepository(acquireJcrRepository(jcrConfig), pathManger, typeManager, typeHandlerManager);
      }
  
      @Override
      public void destroy() {
          jcrRepository = null;
          typeManager = null;
      }
  
      @Override
      public CmisService getService(CallContext context) {
          CmisServiceWrapper<JcrService> serviceWrapper = new CmisServiceWrapper<JcrService>(
                  createJcrService(jcrRepository, context), DEFAULT_MAX_ITEMS_TYPES, DEFAULT_DEPTH_TYPES,
                  DEFAULT_MAX_ITEMS_OBJECTS, DEFAULT_DEPTH_OBJECTS);
  
          serviceWrapper.getWrappedService().setCallContext(context);
          return serviceWrapper;
      }
  
      //------------------------------------------< factories >---
  
      /**
       * Acquire the JCR repository given a configuration. This implementation used
       * {@link javax.imageio.spi.ServiceRegistry#lookupProviders(Class)} for
       * locating <code>RepositoryFactory</code> instances. The first instance
       * which can handle the <code>jcrConfig</code> parameters is used to
       * acquire the repository. 
       *
      * @param jcrConfig  configuration determining the JCR repository to be returned
      * @return
      * @throws RepositoryException
      */
     protected Repository acquireJcrRepository(Map<String, String> jcrConfig) {
         try {
             Iterator<RepositoryFactory> factories = ServiceRegistry.lookupProviders(RepositoryFactory.class);
             while (factories.hasNext()) {
                 RepositoryFactory factory = factories.next();
                 log.debug("Trying to acquire JCR repository from factory " + factory);
                 Repository repository = factory.getRepository(jcrConfig);
                 if (repository != null) {
                     log.debug("Successfully acquired JCR repository from factory " + factory);
                     return repository;
                 }
                 else {
                     log.debug("Could not acquire JCR repository from factory " + factory);
                 }
             }
             throw new CmisConnectionException("No JCR repository factory for configured parameters");
         }
         catch (RepositoryException e) {
             log.debug(e.getMessage(), e);
             throw new CmisConnectionException(e.getMessage(), e);
         }
     }
 
     /**
      * Create a <code>JcrService</code> from a <code>JcrRepository</code>JcrRepository> and
      * <code>CallContext</code>.
      * 
      * @param jcrRepository
      * @param context
      * @return
      */
     protected JcrService createJcrService(JcrRepository jcrRepository, CallContext context) {
         return new JcrService(jcrRepository);
     }
 
     protected JcrTypeManager createTypeManager() {
         return new JcrTypeManager();
     }
 
     protected JcrTypeHandlerManager createTypeHandlerManager(PathManager pathManager, JcrTypeManager typeManager) {
         JcrTypeHandlerManager typeHandlerManager = new JcrTypeHandlerManager(pathManager, typeManager);
         typeHandlerManager.addHandler(new DefaultFolderTypeHandler());
         typeHandlerManager.addHandler(new DefaultDocumentTypeHandler());
         typeHandlerManager.addHandler(new DefaultUnversionedDocumentTypeHandler());
         return typeHandlerManager;
     }
 
     //------------------------------------------< private >---
 
     private void readConfiguration(Map<String, String> parameters) {
         Map<String, String> map = new HashMap<String, String>();
         List<String> keys = new ArrayList<String>(parameters.keySet());
         Collections.sort(keys);
 
         for (String key : keys) {
             if (key.startsWith(PREFIX_JCR_CONFIG)) {
                 String jcrKey = key.substring(PREFIX_JCR_CONFIG.length());
                 String jcrValue = replaceSystemProperties(parameters.get(key));
                 map.put(jcrKey, jcrValue);
             }
 
             else if (MOUNT_PATH_CONFIG.equals(key)) {
                 mountPath = parameters.get(key);
                 log.debug("Configuration: " + MOUNT_PATH_CONFIG + '=' + mountPath);
             }
 
             else {
                 log.warn("Configuration: unrecognized key: " + key);
             }
         }
 
         jcrConfig = Collections.unmodifiableMap(map);
         log.debug("Configuration: jcr=" + jcrConfig);
     }
 
     private static String replaceSystemProperties(String s) {
         if (s == null) {
             return null;
         }
 
         StringBuilder result = new StringBuilder();
         StringBuilder property = null;
         boolean inProperty = false;
 
         for (int i = 0; i < s.length(); i++) {
             char c = s.charAt(i);
 
             if (inProperty) {
                 if (c == '}') {
                     String value = System.getProperty(property.toString());
                     if (value != null) {
                         result.append(value);
                     }
                     inProperty = false;
                 } else {
                     property.append(c);
                 }
             } else {
                 if (c == '{') {
                     property = new StringBuilder();
                     inProperty = true;
                 } else {
                     result.append(c);
                 }
             }
         }
 
         return result.toString();
     }
 
 }