/**
    * 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.wss4j.common.cache;
  
  import java.io.File;
  import java.nio.file.Path;
  import java.time.Instant;
  
  import org.apache.wss4j.common.ext.WSSecurityException;
  import org.ehcache.Cache;
  import org.ehcache.CacheManager;
  import org.ehcache.CachePersistenceException;
  import org.ehcache.PersistentCacheManager;
  import org.ehcache.Status;
  import org.ehcache.config.builders.CacheConfigurationBuilder;
  import org.ehcache.config.builders.CacheManagerBuilder;
  import org.ehcache.config.builders.ResourcePoolsBuilder;
  import org.ehcache.config.units.EntryUnit;
  import org.ehcache.config.units.MemoryUnit;
  
  /**
   * An in-memory EHCache implementation of the ReplayCache interface, that overflows to disk.
   * The default TTL is 60 minutes and the max TTL is 12 hours.
   */
  public class EHCacheReplayCache implements ReplayCache {
  
      private static final org.slf4j.Logger LOG =
              org.slf4j.LoggerFactory.getLogger(EHCacheReplayCache.class);
  
      private final Cache<String, EHCacheValue> cache;
      private final CacheManager cacheManager;
      private final String key;
      private final Path diskstorePath;
      private final boolean persistent;
  
      public EHCacheReplayCache(String key) throws WSSecurityException {
          this(key, null);
      }
  
      public EHCacheReplayCache(String key, Path diskstorePath) throws WSSecurityException {
          this(key, diskstorePath, 50, 10000, false);
      }
  
      public EHCacheReplayCache(String key, Path diskstorePath, long diskSize, long heapEntries, boolean persistent)
              throws WSSecurityException {
          this.key = key;
          this.diskstorePath = diskstorePath;
          this.persistent = persistent;
  
          // Do some checking on the arguments
          if (key == null || persistent && diskstorePath == null) {
              throw new NullPointerException();
          }
          if (diskstorePath != null && (diskSize < 5 || diskSize > 10000)) {
              throw new IllegalArgumentException("The diskSize parameter must be between 5 and 10000 (megabytes)");
          }
          if (heapEntries < 100) {
              throw new IllegalArgumentException("The heapEntries parameter must be greater than 100 (entries)");
          }
  
          try {
              ResourcePoolsBuilder resourcePoolsBuilder = ResourcePoolsBuilder.newResourcePoolsBuilder()
                      .heap(heapEntries, EntryUnit.ENTRIES);
              if (diskstorePath != null) {
                  resourcePoolsBuilder = resourcePoolsBuilder.disk(diskSize, MemoryUnit.MB, persistent);
              }
  
              CacheConfigurationBuilder<String, EHCacheValue> configurationBuilder =
                      CacheConfigurationBuilder.newCacheConfigurationBuilder(
                              String.class, EHCacheValue.class, resourcePoolsBuilder)
                              .withExpiry(new EHCacheExpiry());
  
              if (diskstorePath != null) {
                  cacheManager = CacheManagerBuilder.newCacheManagerBuilder()
                          .with(CacheManagerBuilder.persistence(diskstorePath.toFile()))
                          .withCache(key, configurationBuilder)
                          .build();
              } else {
                  cacheManager = CacheManagerBuilder.newCacheManagerBuilder()
                          .withCache(key, configurationBuilder)
                          .build();
              }
 
             cacheManager.init();
             cache = cacheManager.getCache(key, String.class, EHCacheValue.class);
         } catch (Exception ex) {
             LOG.error("Error configuring EHCacheReplayCache: {}", ex.getMessage());
             throw new WSSecurityException(WSSecurityException.ErrorCode.FAILURE, ex, "replayCacheError");
         }
     }
 
     /**
      * Add the given identifier to the cache. It will be cached for a default amount of time.
      * @param identifier The identifier to be added
      */
     public void add(String identifier) {
         add(identifier, null);
     }
 
     /**
      * Add the given identifier to the cache to be cached for the given time
      * @param identifier The identifier to be added
      * @param expiry A custom expiry time for the identifier. Can be null in which case, the default expiry is used.
      */
     public void add(String identifier, Instant expiry) {
         if (identifier == null || identifier.length() == 0) {
             return;
         }
 
         cache.put(identifier, new EHCacheValue(identifier, expiry));
     }
 
     /**
      * Return true if the given identifier is contained in the cache
      * @param identifier The identifier to check
      */
     public boolean contains(String identifier) {
         if (cache == null) {
             return false;
         }
         EHCacheValue element = cache.get(identifier);
         return element != null;
     }
 
     // Only exposed for testing
     EHCacheValue get(String identifier) {
         return cache.get(identifier);
     }
 
     @Override
     public synchronized void close() {
         if (cacheManager.getStatus() == Status.AVAILABLE) {
             cacheManager.removeCache(key);
 
             cacheManager.close();
 
             if (!persistent && cacheManager instanceof PersistentCacheManager) {
                 try {
                     ((PersistentCacheManager) cacheManager).destroy();
                 } catch (CachePersistenceException e) {
                     LOG.debug("Error in shutting down persistent cache", e);
                 }
 
                 // As we're not using a persistent disk store, just delete it - it should be empty after calling
                 // destroy above
                 if (diskstorePath != null) {
                     File file = diskstorePath.toFile();
                     if (file.exists() && file.canWrite()) {
                         file.delete();
                     }
                 }
             }
         }
     }
 
     public void initComplete() {
     }
     public void preShutdown() {
         close();
     }
     public void postShutdown() {
         close();
     }
 
 }