/*
    * 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.omid;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.curator.RetryPolicy;
  import org.apache.curator.framework.CuratorFramework;
  import org.apache.curator.framework.CuratorFrameworkFactory;
  import org.apache.curator.retry.ExponentialBackoffRetry;
  import org.apache.curator.test.TestingServer;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  import java.net.ServerSocket;
  import java.net.Socket;
  
  /**
   * This class contains functionality that is useful for the Omid tests.
   */
  public class TestUtils {
  
      private static final Logger LOG = LoggerFactory.getLogger(TestUtils.class);
  
      private static final int DEFAULT_ZK_PORT = 2181;
  
      public static int getFreeLocalPort() throws IOException {
  
          try (ServerSocket socket = new ServerSocket(0)) {
              socket.setReuseAddress(true);
              return socket.getLocalPort();
          }
  
      }
  
      public static TestingServer provideTestingZKServer(int port) throws Exception {
  
          return new TestingServer(port);
  
      }
  
      public static TestingServer provideTestingZKServer() throws Exception {
  
          return provideTestingZKServer(DEFAULT_ZK_PORT);
  
      }
  
      public static CuratorFramework provideConnectedZKClient(String zkCluster) throws Exception {
  
          LOG.info("Creating Zookeeper Client connecting to {}", zkCluster);
  
          RetryPolicy retryPolicy = new ExponentialBackoffRetry(1000, 3);
          CuratorFramework zkClient = CuratorFrameworkFactory.builder().namespace("omid")
                  .connectString(zkCluster).retryPolicy(retryPolicy).build();
  
          LOG.info("Connecting to ZK cluster {}", zkClient.getState());
          zkClient.start();
          zkClient.blockUntilConnected();
          LOG.info("Connection to ZK cluster {}", zkClient.getState());
  
          return zkClient;
      }
  
      public static void waitForSocketListening(String host, int port, int sleepTimeMillis)
              throws IOException, InterruptedException {
          while (true) {
              Socket sock = null;
              try {
                  sock = new Socket(host, port);
              } catch (IOException e) {
                  // ignore as this is expected
                  Thread.sleep(sleepTimeMillis);
                  continue;
              } finally {
                  IOUtils.closeQuietly(sock);
              }
              LOG.info("Host " + host + ":" + port + " is up...");
              break;
          }
      }
  
      public static void waitForSocketNotListening(String host, int port, int sleepTimeMillis)
              throws IOException, InterruptedException {
          while (true) {
             Socket sock = null;
             try {
                 sock = new Socket(host, port);
             } catch (IOException e) {
                 // ignore as this is expected
                 break;
             } finally {
                 IOUtils.closeQuietly(sock);
             }
             Thread.sleep(sleepTimeMillis);
             LOG.info("Host " + host + ":" + port + " is still up...");
         }
     }
 
 }