package eu.simuline.testhelpers;
   
   import eu.simuline.util.images.GifResource;
   
   import java.awt.event.ActionEvent;
   import java.awt.event.KeyEvent;
   
   import javax.swing.AbstractAction;
   import javax.swing.KeyStroke;
  import javax.swing.SwingUtilities;
  
  import org.junit.runner.JUnitCore;
  import org.junit.runner.Request;
  import org.junit.runner.Runner;
  import org.junit.runner.Result;
  import org.junit.runner.Description;
  
  import org.junit.runner.manipulation.Filter;
  
  import org.junit.runner.notification.RunListener;
  import org.junit.runner.notification.RunNotifier;
  import org.junit.runner.notification.StoppedByUserException;
  
  import org.javalobby.icons20x20.Open;
  import org.javalobby.icons20x20.ExecuteProject;
  import org.javalobby.icons20x20.Stop;
  import org.javalobby.icons20x20.Hammer;
  import org.javalobby.icons20x20.Delete;
  
  
  /**
   * Represents the actions of the test GUI inspired by old junit GUI. 
   * **** Moreover provides a wrapper to access junit 
   * and the access point to run the gui started from the class to be tested. 
   * ****
   * The fundamental methods are {@link #runFromMain()} 
   * which runs the test class from its main method and 
   * {@link #runTestClass(String)} which runs a testclass with the given name. 
   *
   * @see GUIRunner
   * @see GUIRunListener
   * 
   * Created: Tue Jun 13 02:53:06 2006
   *
   * @author <a href="mailto:ernst.reissner@simuline.eu">Ernst Reissner</a>
   * @version 1.0
   */
  public final class Actions {
  
      /* -------------------------------------------------------------------- *
       * inner classes and enums.                                             *
       * -------------------------------------------------------------------- */
  
      /**
       * The action of opening a <code>java</code>-file defining a test class 
       * and starting the tests defined by it. 
       */
      class OpenAction extends AbstractAction {
  
  	private static final long serialVersionUID = -589L;
  
  	OpenAction() {
  	    super("Open", GifResource.getIcon(Open.class));
  	    putValue(SHORT_DESCRIPTION, "Opens a class and executes run. ");
              putValue(MNEMONIC_KEY, KeyEvent.VK_O);
              putValue(ACCELERATOR_KEY,
  		     KeyStroke.getKeyStroke(KeyEvent.VK_O,
  					    ActionEvent.CTRL_MASK));
  	}
  
  	public void actionPerformed(ActionEvent event) {
  	    String clsName = Actions.this.guiRunner.openClassChooser();
  
  	    if (clsName == null) {
  		// open action was not successful
  		System.out.println("Warning: no class choosen");
  		return;
  	    }
  	    assert clsName != null;
  	    System.out.println("Info: class `" + clsName + "' choosen");
  	    Actions.this.coreRunner = new CoreRunner(clsName);
  
  	    // clears list of failed testcases
  	    Actions.this.filter = null;
  	    Actions.this.getStartAction().actionPerformed(null);
  	}
      } // class OpenAction 
  
  
      /**
       * The action of starting the testcases in the loaded testclass. 
       */
      class StartAction extends AbstractAction {
  
  	private static final long serialVersionUID = -589L;
  
  	StartAction() {
  	    super("Run", GifResource.getIcon(ExecuteProject.class));
  	    putValue(SHORT_DESCRIPTION, "Runs the testcases. ");
             putValue(MNEMONIC_KEY, KeyEvent.VK_R);
             putValue(ACCELERATOR_KEY,
 		     KeyStroke.getKeyStroke(KeyEvent.VK_R,
 					    ActionEvent.CTRL_MASK));
 	}
 
 	public void actionPerformed(ActionEvent event) {
  	    Actions.this.coreRunner = new CoreRunner(Actions.this.coreRunner);
 	    Actions.this.coreRunner.start();
 	}
     } // class StartAction 
 
     /**
      * The action of stopping the test run//  after having finished 
      * the currently running testcase. 
      */
     class StopAction extends AbstractAction {
 
     	private static final long serialVersionUID = -589L;
 
     	StopAction() {
     	    super("Stop", GifResource.getIcon(Stop.class));
     	    putValue(SHORT_DESCRIPTION, 
     		     "Stops after having executed the current testcase. ");
             putValue(MNEMONIC_KEY, KeyEvent.VK_S);
             putValue(ACCELERATOR_KEY,
     		     KeyStroke.getKeyStroke(KeyEvent.VK_S,
     					    ActionEvent.CTRL_MASK));
     	}
 
      	public void actionPerformed(ActionEvent event) {
 	    Actions.this.coreRunner.pleaseStop();
 	}
     } // class StopAction 
 
     /**
      * The action of breaking the sequence of testcases currently running. 
      * Tries to stop the currently running testcase 
      * but guarantees only that the break is effected 
      * after the current testcase has finished. 
      */
     class BreakAction extends AbstractAction {
 
 	private static final long serialVersionUID = -589L;
 
 	BreakAction() {
 	    super("Break", GifResource.getIcon(Hammer.class));
 	    putValue(SHORT_DESCRIPTION, 
 		     "Tries to break execution of current testcases. ");
             putValue(MNEMONIC_KEY, KeyEvent.VK_B);
             putValue(ACCELERATOR_KEY,
 		     KeyStroke.getKeyStroke(KeyEvent.VK_B,
 					    ActionEvent.CTRL_MASK));
 	}
 
 	@SuppressWarnings("deprecation")// because no alternative to stop. 
 	public void actionPerformed(ActionEvent event) {
 	    //setEnableForRun(false); // !isRunning
 	    System.out.println("Break...");
 	    Actions.this.coreRunner.pleaseStop(); // avoids going on after stop 
 	    // method stop is deprecated but there is no alternative
 	    // TBD: rework: shall throw exception. 
 			// original argument: deprecated?
 	    Actions.this.coreRunner.stop(); //new StoppedByUserException()
 	}
     } // class BreakAction 
 
 
     /**
      * The action of exiting the tester application. 
      */
     static class ExitAction extends AbstractAction {
 
 	private static final long serialVersionUID = -589L;
 
 	ExitAction() {
 	    super("Exit", GifResource.getIcon(Delete.class));
 	    putValue(SHORT_DESCRIPTION, 
 		     "Quits this application immediately. ");
             putValue(MNEMONIC_KEY, KeyEvent.VK_E);
             putValue(ACCELERATOR_KEY,
 		     KeyStroke.getKeyStroke(KeyEvent.VK_E,
 					    ActionEvent.CTRL_MASK));
 	}
 
 	@edu.umd.cs.findbugs.annotations.SuppressWarnings
 	(value = "DM_EXIT", 
 	 justification = "To ensure safe exit " + 
 	 "not reached by throwing exception. " + 
 	 "Also Actions is not invoked by other code. ")
 	public void actionPerformed(ActionEvent event) {
 	    //throw new RuntimeException("Exit by user action. ");
 	    System.exit(0);
 	}
     } // class ExitAction 
 
     /**
      * A thread in which a testclass is executed 
      * or at least a single testcase out of this testclass. 
      * Essentially, this is defined by the class {@link #testClassName}. 
      * The major task of this class is, to reload {@link #testClassName} 
      * using a classloader which allows reloading 
      * each test run without restarting the tester application. 
      * The core of the code is copied from {@link JUnitCore}. 
      */
     class CoreRunner extends Thread {
 
 	/* ---------------------------------------------------------------- *
 	 * fields.                                                          *
 	 * ---------------------------------------------------------------- */
 
 	/**
 	 * The notifier to run the tests as in JUnitCore. 
 	 */
 	private final RunNotifier notifier;
 
 	/**
 	 * The name of the class to be tested. 
 	 */
 	private final String testClassName;
 
 	/* ---------------------------------------------------------------- *
 	 * constructors.                                                    *
 	 * ---------------------------------------------------------------- */
 
 	/**
 	 * Creates a runner running all testcases in the given test class. 
 	 */
 	CoreRunner(String testClassName)  {
 	    this.notifier = new RunNotifier();
 	    this.notifier.addListener(Actions.this.listener);
 
 	    this.testClassName = testClassName;
 	}
 
 	/**
 	 * Copy constructor. 
 	 */
 	CoreRunner(CoreRunner other)  {
 	    this(other.testClassName);
 	}
 
 	/* ---------------------------------------------------------------- *
 	 * methods.                                                         *
 	 * ---------------------------------------------------------------- */
 
 
 	// api-docs inherited from Runnable 
 	// overwrites void implementation provided by class Thread 
 	/**
 	 * Loads the class with name {@link #testClassName} 
 	 * with a {@link TestCaseClassLoader} to allow reloading. 
 	 * Then creates a {@link Request} filtering it with {@link #filter} 
 	 * defining the tests to be run and runs those tests 
 	 * invoking {@link #run(Request)}. 
 	 */
 	public void run() {
 	    Class<?> newTestClass = null;
 	    try {
 		newTestClass = new TestCaseClassLoader()
 		    .loadClass(this.testClassName, true);
 	    } catch (ClassNotFoundException e) {
 		throw new IllegalStateException// NOPMD
 		    ("Testclass '" + this.testClassName + "' disappeared. ");
 		// **** This makes the problem 
 		// that in the GUI the run button is shaded 
 		// (and the stop button is not). 
 	    }
 	    assert newTestClass != null;
 
 	    Request request = Request.aClass(newTestClass);
 	    //Request request = Request.classes(newTestClass);
 	    if (Actions.this.filter != null && Actions.this.filter.isTest()) {
 		request = request.filterWith(Actions.this.filter);
 	    } else {
 		Actions.this.listener.testClassStructureLoaded
 		    (request.getRunner().getDescription());
 	    }
 
 	    try {
 		run(request);
 	    } catch (StoppedByUserException ee) {
 		// either Break or Stop 
   		Actions.this.listener.testRunAborted();
   	    }
 
 	    //System.out.println("...Core run()"+this.core);
 	}
 
 	// almost copy from JUnitCore
 	public void run(Request request) {
 	    Runner runner = request.getRunner();
 	    Result result = new Result();
 	    RunListener listener = result.createListener();
 	    this.notifier.addFirstListener(listener);
 	    try {
 		this.notifier.fireTestRunStarted(runner.getDescription());
 		runner.run(this.notifier);
 		this.notifier.fireTestRunFinished(result);
 	    } finally {
 		this.notifier.removeListener(listener);
 	    }
 	}
 
 	public void pleaseStop() {
 	    this.notifier.pleaseStop();
 	}
 
     } // class CoreRunner 
 
     /* -------------------------------------------------------------------- *
      * fields.                                                              *
      * -------------------------------------------------------------------- */
 
 
     /**
      * The action to open a new testclass. 
      */
     private final  OpenAction  openAction;
 
     /**
      * The action to run a testcase. 
      */
     private final StartAction startAction;
 
     /**
      * The action to stop after having finished the currently running testcase. 
      */
     private final  StopAction  stopAction;
 
     /**
      * The action to break execution of testcases. 
      * Tries to break the currently running testcase 
      * and does not go on with further testcases. 
      */
     private final BreakAction breakAction;
 
     private final GUIRunner guiRunner;
 
     private CoreRunner coreRunner;
 
     private final ExtRunListener listener;
 
  
     /**
      * Defines whether a test is running. 
      * This is used to activate/deactivate the actions 
      * {@link #openAction}, {@link #startAction}, {@link #stopAction} 
      * and {@link #breakAction}. 
      */
     private boolean isRunning;
 
     // to run a single testcase **** may be null 
     // which signifies that all tests shall be executed. 
     // shall be replaced by compounds. 
     /**
      * Defines the filter for tests to be run. 
      * **** may be null 
      *
      * @see #setFilter(Description)
      * @see Actions.CoreRunner#run()
      */
     private Description filter;
 
     /* -------------------------------------------------------------------- *
      * constructor.                                                         *
      * -------------------------------------------------------------------- */
 
     /**
      * Creates a new <code>Actions</code> instance.
      *
      * @param testClassName
      *    the name of the test class. 
      */
     @SuppressWarnings("checkstyle:nowhitespaceafter")
     public Actions(String testClassName) {
 
 	this. openAction = new  OpenAction();
 	this.startAction = new StartAction();
 	this. stopAction = new  StopAction();
 	this.breakAction = new BreakAction();
 
 	this.guiRunner  = new GUIRunner(this);
 	this.listener   = new SeqRunListener(this.guiRunner);
 
 	this.coreRunner = new CoreRunner(testClassName);
 	this.isRunning  = false;
 	this.filter     = null; // **** to be reworked 
     }
 
     /* -------------------------------------------------------------------- *
      * methods.                                                             *
      * -------------------------------------------------------------------- */
 
 
     private static boolean descShouldRun(Description desc, 
 					 Description desiredDesc) {
 	assert desc.isTest();
 	if (desiredDesc.isTest()) {
 	    return desiredDesc.equals(desc);
 	}
 	for (Description each : desiredDesc.getChildren()) {
 	    if (descShouldRun(desc, each)) {
 		return true;
 	    }
 	}
 	return false;
     }
 
     // required only because of a bug in junit. 
     /**
      * Returns a {@code Filter} that only runs methods in 
      * desiredDesc. 
      *
      * @param desiredDesc
      *    a description of the tests to be run. 
      * @return
      *    a {@code Filter} that only runs methods in <code>desiredDesc</code>. 
      */
     public static Filter desc2filter(final Description desiredDesc) {
         return new Filter() {
             @Override
             public boolean shouldRun(Description desc) {
 		return descShouldRun(desc, desiredDesc);
                }
 
             @Override
             public String describe() {
                 return String.format("Methods %s", 
 				     desiredDesc.getDisplayName());
             }
         };
     }
 
 
     /**
      * The fundamental method to start tests with the underlying JUnit-GUI. 
      * The test class is supposed to define a method <code>main</code> 
      * with body <code>Actions.run(&lt;testclass&gt;.class);</code>. 
      *
      * @param testClassName
      *    the name of the test class to represent and run. 
      * @see JUnitSingleTester
      * @see #runFromMain()
      */
     static void runTestClass(final String testClassName) {
 	Runnable guiCreator = new Runnable() {
 		public void run() {
 		    // parameter null is nowhere used. 
 		    new Actions(testClassName)
 			.startAction.actionPerformed(null);
 		}
         };
  
         // execute in Event-Dispatch-Thread 
         SwingUtilities.invokeLater(guiCreator);
     }
 
     /**
      * The fundamental method to start tests with the underlying JUnit-GUI. 
      * The test class is supposed to define a method <code>main</code> 
      * with body <code>Actions.runFromMain();</code>. 
      * Essentially invokes {@link #runTestClass(String)} 
      * with the proper test class name. 
      */
     public static void runFromMain() {
 	runTestClass(new Throwable().getStackTrace()[1].getClassName());
 	// TBD: use instead
 	// Thread.currentThread().getStackTrace()[1].getClassName()
 	// avoiding creating a throwable which is nowhere used. 
     }
 
     GUIRunner getRunner() {
 	return this.guiRunner;
     }
 
     /**
      * Sets {@link #filter} according to <code>filter</code>. 
      *
      * @param filter
      *    the filter for the tests to be run 
      */
     void setFilter(Description filter) {
 	assert filter != null;
 	this.filter = filter;
     }
 
     /**
      * Updates the action-enablements 
      * depending on whether a test is running or not: 
      * Open and Start action are enabled iff no test is running, 
      * whereas stop and break actions are enabled iff some test is running. 
      *
      * @param isRunning
      *    whether a test is running. 
      */
     @SuppressWarnings("checkstyle:nowhitespaceafter")
     void setEnableForRun(boolean isRunning) {	
 	assert this.isRunning ^ isRunning;
 	this.isRunning = isRunning;
 	this. openAction.setEnabled(!this.isRunning);
 	this.startAction.setEnabled(!this.isRunning);
 	this. stopAction.setEnabled( this.isRunning);
 	this.breakAction.setEnabled( this.isRunning); //(true);
     }
 
     AbstractAction getOpenAction() {
 	return this.openAction;
     }
 
     AbstractAction getStartAction() {
 	return this.startAction;
     }
 
     AbstractAction getStopAction() {
 	return this.stopAction;
     }
 
     AbstractAction getBreakAction() {
 	return this.breakAction;
     }
 
     AbstractAction getExitAction() {
 	return new ExitAction();
     }
 
     public static void main(String[] args) {
 	runFromMain();
     }
 }