/**
 * Copyright 2008 Google Inc.
 *
 * Licensed 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.waveprotocol.wave.client.scheduler;

import org.waveprotocol.wave.client.scheduler.Scheduler.IncrementalTask;

import org.jmock.Expectations;
import org.jmock.integration.junit3.MockObjectTestCase;

/**
 * Test case for IdempotentScheduler.
 *
 */

public class IdempotentSchedulerTest extends MockObjectTestCase {

  // Mocks.
  private IncrementalTask task;
  private TimerService timer;
  private int delay;

  // Test target.
  private IdempotentScheduler is;

  @Override
  protected void setUp() {
    task = mock(IncrementalTask.class);
    timer = mock(TimerService.class);
    delay = 50;

    is = IdempotentScheduler.builder().with(timer).with(delay).build(task);
  }

  public void testSchedulesItselfAsTheTask() {
    checking(new Expectations() {{
        oneOf(timer).isScheduled(with(is));
        will(returnValue(false));
        oneOf(timer).scheduleRepeating(is, delay, delay);
    }});

    is.schedule();
  }

  public void testCancelsItselfAsTheTask() {
    checking(new Expectations() {{
      oneOf(timer).isScheduled(with(is));
      will(returnValue(true));
      oneOf(timer).cancel(is);
    }});

    is.cancel();
  }
  public void testSchedulerExecutesTask() {
    checking(new Expectations() {{
      oneOf(task).execute();
    }});

    is.execute();
  }

  public void testMultipleScheduleCallsScheduleExactlyOnce() {
    checking(new Expectations() {{
      oneOf(timer).isScheduled(with(is));
      will(returnValue(false));
      oneOf(timer).scheduleRepeating(is, delay, delay);
      oneOf(timer).isScheduled(with(is));
      will(returnValue(true));
    }});

    is.schedule();
    is.schedule();
  }

  public void testCancelWillNotCancelIfNotScheduled() {
    checking(new Expectations() {{
      oneOf(timer).isScheduled(with(is));
      will(returnValue(false));
    }});

    is.cancel();
  }

  public void testWillRescheduleAfterTaskCompletion() {
    checking(new Expectations() {{
      oneOf(timer).isScheduled(with(is));
      will(returnValue(false));
      oneOf(timer).scheduleRepeating(is, delay, delay);
      oneOf(task).execute();
      will(returnValue(false));  // Indicates termination
      oneOf(timer).isScheduled(with(is));
      will(returnValue(false));
      oneOf(timer).scheduleRepeating(is, delay, delay);
    }});

    is.schedule();
    is.execute();  // Simulates call by timer.
    is.schedule();
  }

  public void testWillRescheduleAfterCancel() {
    checking(new Expectations() {{
      oneOf(timer).isScheduled(with(is)); will(returnValue(false));
      oneOf(timer).scheduleRepeating(is, delay, delay);
      oneOf(timer).isScheduled(with(is)); will(returnValue(true));
      oneOf(timer).cancel(is);
      oneOf(timer).isScheduled(with(is));
      will(returnValue(false));
      oneOf(timer).scheduleRepeating(is, delay, delay);
    }});

    is.schedule();
    is.cancel();
    is.schedule();
  }
}