/**
 * 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.
 */

#ifndef __ZOOKEEPER_TEST_SERVER_HPP__
#define __ZOOKEEPER_TEST_SERVER_HPP__

#include <jni.h>

#include <glog/logging.h>

#include <stout/os.hpp>

#include "jvm/jvm.hpp"

#include "zookeeper/zookeeper.hpp"

namespace mesos {
namespace internal {
namespace tests {

// An in-process ZooKeeper server that can be manipulated to control
// repeatable client tests. Sessions can be programmatically expired
// and network partitions can be forced to simulate common failure
// modes.
class ZooKeeperTestServer
{
public:
  ZooKeeperTestServer(Jvm* jvm);
  ~ZooKeeperTestServer();

  // Gets a connection string that can be used to attach a ZooKeeper client to
  // this server.
  std::string connectString() const;

  // Shuts down the network connection to this server.
  void shutdownNetwork();

  // Starts the network connection to this server.  Binds an ephemeral port on
  // the first call and re-uses the port on subsequent calls.
  int startNetwork();

  // Forces the server to expire the given session.
  // Note that there is a delay (~3s) for the corresponding client to receive
  // a session expiration event notification from the ZooKeeper server.
  // TODO(vinod): Fix this so that the notification is immediate.
  // One possible solution is suggested at :
  // http://wiki.apache.org/hadoop/ZooKeeper/FAQ#A4
  // But according to,
  // http://comments.gmane.org/gmane.comp.java.hadoop.zookeeper.user/4489
  // the C binding for ZooKeeper does not yet support multiple
  // clients with the same session id.
  void expireSession(int64_t sessionId);

private:
  // TODO(John Sirois): factor out TemporaryDirectory + createTempDir() to utils
  struct TemporaryDirectory
  {
    Jvm* jvm;
    const std::string path;
    const jobject file;

    TemporaryDirectory(Jvm* _jvm,
                       const std::string& _path,
                       const jobject _file) : jvm(_jvm),
                                              path(_path),
                                              file(_file) {}

    ~TemporaryDirectory()
    {
      jvm->deleteGlobalRef(file);
      Try<Nothing> rmdir = os::rmdir(path);
      if (rmdir.isError()) {
        LOG(WARNING) << "Failed to delete temp dir '"
                     << path << "': " << rmdir.error();
      }
    }
  };

  Jvm* jvm;

  Jvm::JConstructor* fileConstructor;
  jobject snapLog;
  jobject dataTreeBuilder;
  jobject zooKeeperServer;
  Jvm::JMethod* getClientPort;
  Jvm::JMethod* closeSession;

  Jvm::JConstructor* inetSocketAddressConstructor;
  jobject inetSocketAddress;
  Jvm::JConstructor* cnxnFactoryConstructor;
  jobject connectionFactory;
  Jvm::JMethod* startup;
  Jvm::JMethod* isAlive;
  Jvm::JMethod* shutdown;

  int port;
  bool started;
  const TemporaryDirectory* dataDir;
  const TemporaryDirectory* snapDir;

  const TemporaryDirectory* createTempDir();
  void checkStarted() const;
};

} // namespace tests {
} // namespace internal {
} // namespace mesos {

#endif // __ZOOKEEPER_TEST_SERVER_HPP__