/*
 * Copyright 2010-2020 Alfresco Software, Ltd.
 *
 * 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.activiti.engine.test;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import org.activiti.engine.ActivitiException;
import org.activiti.engine.HistoryService;
import org.activiti.engine.ManagementService;
import org.activiti.engine.ProcessEngine;
import org.activiti.engine.ProcessEngineConfiguration;
import org.activiti.engine.RepositoryService;
import org.activiti.engine.RuntimeService;
import org.activiti.engine.TaskService;
import org.activiti.engine.impl.cfg.ProcessEngineConfigurationImpl;
import org.activiti.engine.impl.test.TestHelper;
import org.activiti.engine.test.mock.ActivitiMockSupport;
import org.junit.internal.AssumptionViolatedException;
import org.junit.rules.TestRule;
import org.junit.rules.TestWatcher;
import org.junit.runner.Description;
import org.junit.runners.model.MultipleFailureException;
import org.junit.runners.model.Statement;

/**
 * Convenience for ProcessEngine and services initialization in the form of a JUnit rule.
 *
 * <p>
 * Usage:
 * </p>
 *
 * <pre>
 * public class YourTest {
 *
 *   &#64;Rule
 *   public ActivitiRule activitiRule = new ActivitiRule();
 *
 *   ...
 * }
 * </pre>
 *
 * <p>
 * The ProcessEngine and the services will be made available to the test class through the getters of the activitiRule. The processEngine will be initialized by default with the activiti.cfg.xml
 * resource on the classpath. To specify a different configuration file, pass the resource location in {@link #ActivitiRule(String) the appropriate constructor}. Process engines will be cached
 * statically. Right before the first time the setUp is called for a given configuration resource, the process engine will be constructed.
 * </p>
 *
 * <p>
 * You can declare a deployment with the {@link Deployment} annotation. This base class will make sure that this deployment gets deployed before the setUp and
 * {@link RepositoryService#deleteDeployment(String, boolean) cascade deleted} after the tearDown.
 * </p>
 *
 * <p>
 * The activitiRule also lets you {@link ActivitiRule#setCurrentTime(Date) set the current time used by the process engine}. This can be handy to control the exact time that is used by the engine in
 * order to verify e.g. e.g. due dates of timers. Or start, end and duration times in the history service. In the tearDown, the internal clock will automatically be reset to use the current system
 * time rather then the time that was set during a test method.
 * </p>
 *
 */
public class ActivitiRule implements TestRule {

  protected String configurationResource = "activiti.cfg.xml";
  protected String deploymentId;

  protected ProcessEngineConfiguration processEngineConfiguration;
  protected ProcessEngine processEngine;
  protected RepositoryService repositoryService;
  protected RuntimeService runtimeService;
  protected TaskService taskService;
  protected HistoryService historyService;
  protected ManagementService managementService;

  protected ActivitiMockSupport mockSupport;

  public ActivitiRule() {
  }

  public ActivitiRule(String configurationResource) {
    this.configurationResource = configurationResource;
  }

  public ActivitiRule(ProcessEngine processEngine) {
    setProcessEngine(processEngine);
  }

  /**
   * Implementation based on {@link TestWatcher}.
   */
  @Override
  public Statement apply(final Statement base, final Description description) {
    return new Statement() {
      @Override
      public void evaluate() throws Throwable {
        List<Throwable> errors = new ArrayList<Throwable>();

        startingQuietly(description, errors);
        try {
          base.evaluate();
          succeededQuietly(description, errors);
        } catch (AssumptionViolatedException e) {
          errors.add(e);
          skippedQuietly(e, description, errors);
        } catch (Throwable t) {
          errors.add(t);
          failedQuietly(t, description, errors);
        } finally {
          finishedQuietly(description, errors);
        }

        MultipleFailureException.assertEmpty(errors);
      }
    };
  }

  private void succeededQuietly(Description description, List<Throwable> errors) {
    try {
      succeeded(description);
    } catch (Throwable t) {
      errors.add(t);
    }
  }

  private void failedQuietly(Throwable t, Description description, List<Throwable> errors) {
    try {
      failed(t, description);
    } catch (Throwable t1) {
      errors.add(t1);
    }
  }

  private void skippedQuietly(AssumptionViolatedException e, Description description, List<Throwable> errors) {
    try {
      skipped(e, description);
    } catch (Throwable t) {
      errors.add(t);
    }
  }

  private void startingQuietly(Description description, List<Throwable> errors) {
    try {
      starting(description);
    } catch (Throwable t) {
      errors.add(t);
    }
  }

  private void finishedQuietly(Description description, List<Throwable> errors) {
    try {
      finished(description);
    } catch (Throwable t) {
      errors.add(t);
    }
  }

  /**
   * Invoked when a test succeeds
   */
  protected void succeeded(Description description) {
  }

  /**
   * Invoked when a test fails
   */
  protected void failed(Throwable e, Description description) {
  }

  /**
   * Invoked when a test is skipped due to a failed assumption.
   */
  protected void skipped(AssumptionViolatedException e, Description description) {
  }

  protected void starting(Description description) {
    if (processEngine == null) {
      initializeProcessEngine();
    }

    if (processEngineConfiguration == null) {
      initializeServices();
    }

    if (mockSupport == null) {
      initializeMockSupport();
    }

    // Allow for mock configuration
    configureProcessEngine();

    // Allow for annotations
    try {
      TestHelper.annotationMockSupportSetup(Class.forName(description.getClassName()), description.getMethodName(), mockSupport);
    } catch (ClassNotFoundException e) {
      throw new ActivitiException("Programmatic error: could not instantiate " + description.getClassName(), e);
    }

    try {
      deploymentId = TestHelper.annotationDeploymentSetUp(processEngine, Class.forName(description.getClassName()), description.getMethodName());
    } catch (ClassNotFoundException e) {
      throw new ActivitiException("Programmatic error: could not instantiate " + description.getClassName(), e);
    }
  }

  protected void initializeProcessEngine() {
    processEngine = TestHelper.getProcessEngine(configurationResource);
  }

  protected void initializeServices() {
    processEngineConfiguration = processEngine.getProcessEngineConfiguration();
    repositoryService = processEngine.getRepositoryService();
    runtimeService = processEngine.getRuntimeService();
    taskService = processEngine.getTaskService();
    historyService = processEngine.getHistoryService();
    managementService = processEngine.getManagementService();
  }

  protected void initializeMockSupport() {
    if (ActivitiMockSupport.isMockSupportPossible(processEngine)) {
      this.mockSupport = new ActivitiMockSupport(processEngine);
    }
  }

  protected void configureProcessEngine() {
    /** meant to be overridden */
  }

  protected void finished(Description description) {

    // Remove the test deployment
    try {
      TestHelper.annotationDeploymentTearDown(processEngine, deploymentId, Class.forName(description.getClassName()), description.getMethodName());
    } catch (ClassNotFoundException e) {
      throw new ActivitiException("Programmatic error: could not instantiate " + description.getClassName(), e);
    }

    // Reset internal clock
    processEngineConfiguration.getClock().reset();

    // Rest mocks
    if (mockSupport != null) {
      TestHelper.annotationMockSupportTeardown(mockSupport);
    }
  }

  public void setCurrentTime(Date currentTime) {
    processEngineConfiguration.getClock().setCurrentTime(currentTime);
  }

  public String getConfigurationResource() {
    return configurationResource;
  }

  public void setConfigurationResource(String configurationResource) {
    this.configurationResource = configurationResource;
  }

  public ProcessEngine getProcessEngine() {
    return processEngine;
  }

  public void setProcessEngine(ProcessEngine processEngine) {
    this.processEngine = processEngine;
    initializeServices();
  }

  public RepositoryService getRepositoryService() {
    return repositoryService;
  }

  public void setRepositoryService(RepositoryService repositoryService) {
    this.repositoryService = repositoryService;
  }

  public RuntimeService getRuntimeService() {
    return runtimeService;
  }

  public void setRuntimeService(RuntimeService runtimeService) {
    this.runtimeService = runtimeService;
  }

  public TaskService getTaskService() {
    return taskService;
  }

  public void setTaskService(TaskService taskService) {
    this.taskService = taskService;
  }

  public HistoryService getHistoryService() {
    return historyService;
  }

  public void setHistoricDataService(HistoryService historicDataService) {
    this.historyService = historicDataService;
  }

  public ManagementService getManagementService() {
    return managementService;
  }

  public void setManagementService(ManagementService managementService) {
    this.managementService = managementService;
  }

  public void setProcessEngineConfiguration(ProcessEngineConfigurationImpl processEngineConfiguration) {
    this.processEngineConfiguration = processEngineConfiguration;
  }

  public ActivitiMockSupport getMockSupport() {
    return mockSupport;
  }

  public ActivitiMockSupport mockSupport() {
    return mockSupport;
  }

}
