/*
    * 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.logging.log4j.mongodb3;
  
  import org.apache.logging.log4j.Level;
  import org.apache.logging.log4j.Logger;
  import org.apache.logging.log4j.core.appender.AppenderLoggingException;
  import org.apache.logging.log4j.core.appender.nosql.AbstractNoSqlConnection;
  import org.apache.logging.log4j.core.appender.nosql.NoSqlConnection;
  import org.apache.logging.log4j.core.appender.nosql.NoSqlObject;
  import org.apache.logging.log4j.status.StatusLogger;
  import org.bson.BSON;
  import org.bson.Document;
  import org.bson.Transformer;
  
  import com.mongodb.MongoClient;
  import com.mongodb.MongoException;
  import com.mongodb.client.MongoCollection;
  import com.mongodb.client.MongoDatabase;
  import com.mongodb.client.model.CreateCollectionOptions;
  
  /**
   * The MongoDB implementation of {@link NoSqlConnection}.
   */
  public final class MongoDbConnection extends AbstractNoSqlConnection<Document, MongoDbDocumentObject> {
  
      private static final Logger LOGGER = StatusLogger.getLogger();
  
      static {
          BSON.addEncodingHook(Level.class, new Transformer() {
              @Override
              public Object transform(final Object o) {
                  if (o instanceof Level) {
                      return ((Level) o).name();
                  }
                  return o;
              }
          });
      }
  
      private static MongoCollection<Document> getOrCreateMongoCollection(final MongoDatabase database,
              final String collectionName, final boolean isCapped, final Integer sizeInBytes) {
          try {
              LOGGER.debug("Gettting collection '{}'...", collectionName);
              // throws IllegalArgumentException if collectionName is invalid
              return database.getCollection(collectionName);
          } catch (final IllegalStateException e) {
              LOGGER.debug("Collection '{}' does not exist.", collectionName);
              final CreateCollectionOptions options = new CreateCollectionOptions()
              // @formatter:off
                      .capped(isCapped)
                      .sizeInBytes(sizeInBytes);
              // @formatter:on
              LOGGER.debug("Creating collection {} (capped = {}, sizeInBytes = {})", collectionName, isCapped,
                      sizeInBytes);
              database.createCollection(collectionName, options);
              return database.getCollection(collectionName);
          }
  
      }
  
      private final MongoCollection<Document> collection;
      private final MongoClient mongoClient;
  
      public MongoDbConnection(final MongoClient mongoClient, final MongoDatabase mongoDatabase,
              final String collectionName, final boolean isCapped, final Integer sizeInBytes) {
          this.mongoClient = mongoClient;
          this.collection = getOrCreateMongoCollection(mongoDatabase, collectionName, isCapped, sizeInBytes);
      }
  
      @Override
      public void closeImpl() {
          // LOG4J2-1196
          mongoClient.close();
      }
  
      @Override
      public MongoDbDocumentObject[] createList(final int length) {
          return new MongoDbDocumentObject[length];
      }
  
      @Override
      public MongoDbDocumentObject createObject() {
          return new MongoDbDocumentObject();
      }
 
     @Override
     public void insertObject(final NoSqlObject<Document> object) {
         try {
             final Document unwrapped = object.unwrap();
             LOGGER.debug("Inserting object {}", unwrapped);
             this.collection.insertOne(unwrapped);
         } catch (final MongoException e) {
             throw new AppenderLoggingException("Failed to write log event to MongoDB due to error: " + e.getMessage(),
                     e);
         }
     }
 
 }