/*
 * 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.streams.gplus.providers;

import org.apache.streams.core.StreamsDatum;
import org.apache.streams.google.gplus.configuration.UserInfo;
import org.apache.streams.gplus.provider.GPlusUserDataCollector;
import org.apache.streams.util.api.requests.backoff.BackOffStrategy;
import org.apache.streams.util.api.requests.backoff.impl.ConstantTimeBackOffStrategy;

import com.google.api.client.googleapis.json.GoogleJsonResponseException;
import com.google.api.services.plus.Plus;
import com.google.api.services.plus.model.Person;
import org.junit.Assert;
import org.junit.Test;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;

import java.io.IOException;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;

import static org.mockito.Matchers.anyString;
import static org.mockito.Mockito.doAnswer;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

/**
 * Basic Units for {@link org.apache.streams.gplus.provider.GPlusUserDataCollector}.
 */
public class TestGPlusUserDataCollector {

  private static final String NO_ERROR = "no error";

  /**
   * Test that on success a datum will be added to the queue.
   *
   * @throws Exception Exception
   */
  @Test
  public void testSucessfullPull() throws Exception {
    Plus plus = createMockPlus(0, null);
    BackOffStrategy backOff = new ConstantTimeBackOffStrategy(1);
    BlockingQueue<StreamsDatum> datums = new LinkedBlockingQueue<>();
    UserInfo user = new UserInfo();
    user.setUserId("A");

    GPlusUserDataCollector collector = new GPlusUserDataCollector(plus, backOff, datums, user);
    collector.run();

    Assert.assertEquals(1, datums.size());
    StreamsDatum datum = datums.take();
    Assert.assertNotNull(datum);
    Assert.assertEquals(NO_ERROR, datum.getId());
    Assert.assertNotNull(datum.getDocument());
    Assert.assertTrue(datum.getDocument() instanceof String);
  }

  /**
   * Test that on failure, no datums are output.
   *
   * @throws Exception Exception
   */
  @Test
  public void testFail() throws Exception {
    Plus plus = createMockPlus(3, mock(GoogleJsonResponseException.class));
    UserInfo user = new UserInfo();
    user.setUserId("A");
    BlockingQueue<StreamsDatum> datums = new LinkedBlockingQueue<>();
    BackOffStrategy backOffStrategy = new ConstantTimeBackOffStrategy(1);

    GPlusUserDataCollector collector = new GPlusUserDataCollector(plus, backOffStrategy, datums, user);
    collector.run();

    Assert.assertEquals(0, datums.size());
  }

  private Plus createMockPlus(final int succedOnTry, final Throwable throwable) {
    Plus plus = mock(Plus.class);
    doAnswer(invocationOnMock -> createMockPeople(succedOnTry, throwable)).when(plus).people();
    return plus;
  }

  private Plus.People createMockPeople(final int succedOnTry, final Throwable throwable) {
    Plus.People people = mock(Plus.People.class);
    try {
      when(people.get(anyString())).thenAnswer(invocationOnMock -> createMockGetNoError(succedOnTry, throwable));
    } catch (IOException ioe) {
      Assert.fail("No Excpetion should have been thrown while creating mocks");
    }
    return people;
  }

  private Plus.People.Get createMockGetNoError(final int succedOnTry, final Throwable throwable) {
    Plus.People.Get get = mock(Plus.People.Get.class);
    try {
      doAnswer(new Answer() {
        private int counter = 0;

        @Override
        public Person answer(InvocationOnMock invocationOnMock) throws Throwable {
          if (counter == succedOnTry) {
            Person person = new Person();
            person.setId(NO_ERROR);
            return person;
          } else {
            ++counter;
            throw throwable;
          }
        }
      }).when(get).execute();
    } catch (IOException ioe) {
      Assert.fail("No Excpetion should have been thrown while creating mocks");
    }
    return get;
  }

}
