/*
    * 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.commons.dbcp2.datasources;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.io.ObjectInputStream;
  import java.time.Duration;
  import java.util.ArrayList;
  import java.util.Hashtable;
  import java.util.List;
  import java.util.Map;
  import java.util.Properties;
  import java.util.concurrent.ConcurrentHashMap;
  
  import javax.naming.Context;
  import javax.naming.Name;
  import javax.naming.RefAddr;
  import javax.naming.Reference;
  import javax.naming.spi.ObjectFactory;
  
  import org.apache.commons.dbcp2.ListException;
  import org.apache.commons.dbcp2.Utils;
  
  /**
   * A JNDI ObjectFactory which creates {@code SharedPoolDataSource}s or {@code PerUserPoolDataSource}s
   *
   * @since 2.0
   */
  abstract class InstanceKeyDataSourceFactory implements ObjectFactory {
  
      private static final Map<String, InstanceKeyDataSource> INSTANCE_MAP = new ConcurrentHashMap<>();
  
      /**
       * Closes all pools associated with this class.
       *
       * @throws ListException
       *             a {@link ListException} containing all exceptions thrown by {@link InstanceKeyDataSource#close()}
       * @see InstanceKeyDataSource#close()
       * @since 2.4.0 throws a {@link ListException} instead of, in 2.3.0 and before, the first exception thrown by
       *        {@link InstanceKeyDataSource#close()}.
       */
      public static void closeAll() throws ListException {
          // Get iterator to loop over all instances of this data source.
          final List<Throwable> exceptionList = new ArrayList<>(INSTANCE_MAP.size());
          INSTANCE_MAP.entrySet().forEach(entry -> {
              // Bullet-proof to avoid anything else but problems from InstanceKeyDataSource#close().
              if (entry != null) {
                  @SuppressWarnings("resource")
                  final InstanceKeyDataSource value = entry.getValue();
                  Utils.close(value, exceptionList::add);
              }
          });
          INSTANCE_MAP.clear();
          if (!exceptionList.isEmpty()) {
              throw new ListException("Could not close all InstanceKeyDataSource instances.", exceptionList);
          }
      }
  
      /**
       * Deserializes the provided byte array to create an object.
       *
       * @param data
       *            Data to deserialize to create the configuration parameter.
       *
       * @return The Object created by deserializing the data.
       *
       * @throws ClassNotFoundException
       *            If a class cannot be found during the deserialization of a configuration parameter.
       * @throws IOException
       *            If an I/O error occurs during the deserialization of a configuration parameter.
       */
      protected static final Object deserialize(final byte[] data) throws IOException, ClassNotFoundException {
          ObjectInputStream in = null;
          try {
              in = new ObjectInputStream(new ByteArrayInputStream(data));
              return in.readObject();
          } finally {
              Utils.closeQuietly(in);
          }
      }
  
      static synchronized String registerNewInstance(final InstanceKeyDataSource ds) {
          int max = 0;
          for (final String s : INSTANCE_MAP.keySet()) {
             if (s != null) {
                 try {
                     max = Math.max(max, Integer.parseInt(s));
                 } catch (final NumberFormatException ignored) {
                     // no sweat, ignore those keys
                 }
             }
         }
         final String instanceKey = String.valueOf(max + 1);
         // Put a placeholder here for now, so other instances will not
         // take our key. We will replace with a pool when ready.
         INSTANCE_MAP.put(instanceKey, ds);
         return instanceKey;
     }
 
     static void removeInstance(final String key) {
         if (key != null) {
             INSTANCE_MAP.remove(key);
         }
     }
 
     private Boolean booleanValueOf(RefAddr refAddr) {
         return Boolean.valueOf(toString(refAddr));
     }
 
     /**
      * Creates an instance of the subclass and sets any properties contained in the Reference.
      *
      * @param ref
      *            The properties to be set on the created DataSource
      *
      * @return A configured DataSource of the appropriate type.
      *
      * @throws ClassNotFoundException
      *            If a class cannot be found during the deserialization of a configuration parameter.
      * @throws IOException
      *            If an I/O error occurs during the deserialization of a configuration parameter.
      */
     protected abstract InstanceKeyDataSource getNewInstance(Reference ref) throws IOException, ClassNotFoundException;
 
     /**
      * Implements ObjectFactory to create an instance of SharedPoolDataSource or PerUserPoolDataSource
      */
     @Override
     public Object getObjectInstance(final Object refObj, final Name name, final Context context,
             final Hashtable<?, ?> env) throws IOException, ClassNotFoundException {
         // The spec says to return null if we can't create an instance
         // of the reference
         Object obj = null;
         if (refObj instanceof Reference) {
             final Reference ref = (Reference) refObj;
             if (isCorrectClass(ref.getClassName())) {
                 final RefAddr refAddr = ref.get("instanceKey");
                 if (hasContent(refAddr)) {
                     // object was bound to JNDI via Referenceable API.
                     obj = INSTANCE_MAP.get(refAddr.getContent());
                 } else {
                     // Tomcat JNDI creates a Reference out of server.xml
                     // <ResourceParam> configuration and passes it to an
                     // instance of the factory given in server.xml.
                     String key = null;
                     if (name != null) {
                         key = name.toString();
                         obj = INSTANCE_MAP.get(key);
                     }
                     if (obj == null) {
                         final InstanceKeyDataSource ds = getNewInstance(ref);
                         setCommonProperties(ref, ds);
                         obj = ds;
                         if (key != null) {
                             INSTANCE_MAP.put(key, ds);
                         }
                     }
                 }
             }
         }
         return obj;
     }
 
     private boolean hasContent(final RefAddr refAddr) {
         return refAddr != null && refAddr.getContent() != null;
     }
 
     /**
      * Tests if className is the value returned from getClass().getName().toString().
      *
      * @param className
      *            The class name to test.
      *
      * @return true if and only if className is the value returned from getClass().getName().toString()
      */
     protected abstract boolean isCorrectClass(String className);
 
     boolean parseBoolean(final RefAddr refAddr) {
         return Boolean.parseBoolean(toString(refAddr));
     }
 
     int parseInt(final RefAddr refAddr) {
         return Integer.parseInt(toString(refAddr));
     }
 
     long parseLong(final RefAddr refAddr) {
         return Long.parseLong(toString(refAddr));
     }
 
     private void setCommonProperties(final Reference ref, final InstanceKeyDataSource ikds)
             throws IOException, ClassNotFoundException {
 
         RefAddr refAddr = ref.get("dataSourceName");
         if (hasContent(refAddr)) {
             ikds.setDataSourceName(toString(refAddr));
         }
 
         refAddr = ref.get("description");
         if (hasContent(refAddr)) {
             ikds.setDescription(toString(refAddr));
         }
 
         refAddr = ref.get("jndiEnvironment");
         if (hasContent(refAddr)) {
             final byte[] serialized = (byte[]) refAddr.getContent();
             ikds.setJndiEnvironment((Properties) deserialize(serialized));
         }
 
         refAddr = ref.get("loginTimeout");
         if (hasContent(refAddr)) {
             ikds.setLoginTimeout(toDurationFromSeconds(refAddr));
         }
 
         // Pool properties
         refAddr = ref.get("blockWhenExhausted");
         if (hasContent(refAddr)) {
             ikds.setDefaultBlockWhenExhausted(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("evictionPolicyClassName");
         if (hasContent(refAddr)) {
             ikds.setDefaultEvictionPolicyClassName(toString(refAddr));
         }
 
         // Pool properties
         refAddr = ref.get("lifo");
         if (hasContent(refAddr)) {
             ikds.setDefaultLifo(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("maxIdlePerKey");
         if (hasContent(refAddr)) {
             ikds.setDefaultMaxIdle(parseInt(refAddr));
         }
 
         refAddr = ref.get("maxTotalPerKey");
         if (hasContent(refAddr)) {
             ikds.setDefaultMaxTotal(parseInt(refAddr));
         }
 
         refAddr = ref.get("maxWaitMillis");
         if (hasContent(refAddr)) {
             ikds.setDefaultMaxWait(toDurationFromMillis(refAddr));
         }
 
         refAddr = ref.get("minEvictableIdleTimeMillis");
         if (hasContent(refAddr)) {
             ikds.setDefaultMinEvictableIdle(toDurationFromMillis(refAddr));
         }
 
         refAddr = ref.get("minIdlePerKey");
         if (hasContent(refAddr)) {
             ikds.setDefaultMinIdle(parseInt(refAddr));
         }
 
         refAddr = ref.get("numTestsPerEvictionRun");
         if (hasContent(refAddr)) {
             ikds.setDefaultNumTestsPerEvictionRun(parseInt(refAddr));
         }
 
         refAddr = ref.get("softMinEvictableIdleTimeMillis");
         if (hasContent(refAddr)) {
             ikds.setDefaultSoftMinEvictableIdle(toDurationFromMillis(refAddr));
         }
 
         refAddr = ref.get("testOnCreate");
         if (hasContent(refAddr)) {
             ikds.setDefaultTestOnCreate(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("testOnBorrow");
         if (hasContent(refAddr)) {
             ikds.setDefaultTestOnBorrow(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("testOnReturn");
         if (hasContent(refAddr)) {
             ikds.setDefaultTestOnReturn(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("testWhileIdle");
         if (hasContent(refAddr)) {
             ikds.setDefaultTestWhileIdle(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("timeBetweenEvictionRunsMillis");
         if (hasContent(refAddr)) {
             ikds.setDefaultDurationBetweenEvictionRuns(toDurationFromMillis(refAddr));
         }
 
         // Connection factory properties
 
         refAddr = ref.get("validationQuery");
         if (hasContent(refAddr)) {
             ikds.setValidationQuery(toString(refAddr));
         }
 
         refAddr = ref.get("validationQueryTimeout");
         if (hasContent(refAddr)) {
             ikds.setValidationQueryTimeout(toDurationFromSeconds(refAddr));
         }
 
         refAddr = ref.get("rollbackAfterValidation");
         if (hasContent(refAddr)) {
             ikds.setRollbackAfterValidation(parseBoolean(refAddr));
         }
 
         refAddr = ref.get("maxConnLifetimeMillis");
         if (hasContent(refAddr)) {
             ikds.setMaxConnLifetime(toDurationFromMillis(refAddr));
         }
 
         // Connection properties
 
         refAddr = ref.get("defaultAutoCommit");
         if (hasContent(refAddr)) {
             ikds.setDefaultAutoCommit(booleanValueOf(refAddr));
         }
 
         refAddr = ref.get("defaultTransactionIsolation");
         if (hasContent(refAddr)) {
             ikds.setDefaultTransactionIsolation(parseInt(refAddr));
         }
 
         refAddr = ref.get("defaultReadOnly");
         if (hasContent(refAddr)) {
             ikds.setDefaultReadOnly(booleanValueOf(refAddr));
         }
     }
 
     private Duration toDurationFromMillis(RefAddr refAddr) {
         return Duration.ofMillis(parseLong(refAddr));
     }
 
     private Duration toDurationFromSeconds(RefAddr refAddr) {
         return Duration.ofSeconds(parseInt(refAddr));
     }
 
     String toString(final RefAddr refAddr) {
         return refAddr.getContent().toString();
     }
 }