package com.uc.cep.examples;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Arrays;
import java.util.List;

import org.apache.log4j.Logger;
import org.junit.Assert;

import com.bea.wlevs.ede.api.EventChannel;
import com.uc.cep.examples.ChannelHelper.OutChannels;

/**
 * An example snippet to allow the hijacking of channel sources and listeners.
 * <p>
 * This class mimics Junit TestBase like behaviour in that it:
 * <ul>
 * <li>1. runs the &quot;test&quot; prefixed methods from any subclass</li>
 * <li>2. asserts whether the event went to the correct channel</li>
 * <li>3. checks that if there were any &quot;bad&quot; events found</li>
 * </ul>
 * went to the right channel or the wrong channel.
 * 
 * @author Andrew Upton, Upton Consulting GmbH 2017
 * 
 */
public abstract class TestBase
{
	private static Logger LOGGER = Logger.getLogger(TestBase.class);

	/**
	 * 
	 * @throws Exception
	 */
	public void run() throws Exception
	{
		ChannelHelper chanHelper = LocalBundleActivator.getChannelHelper();
		chanHelper.start();

		TestResult result = new TestResult();

		Method[] methods = this.getClass().getMethods();

		Arrays.asList(methods);

		for (Method method : methods)
		{
			if (method.getName().startsWith("test"))
			{
				setUp(method.getName()); // mimic the JUnit setUp() behaviour

				try
				{
					method.invoke(this, null);
					result.addTestedOK();
				}
				catch (InvocationTargetException e)
				{
					result.addFailed(method.getName(), e);
				}
				catch (Exception e)
				{
					result.addErrored(method.getName(), e);
				}

				tearDown();
			}
			else
			{
				// ignore
			}
		}

		LOGGER.info(result.report());

		chanHelper.stop();
	}

	private void setUp(String name)
	{
		LocalBundleActivator.getChannelHelper().clearAllListeners();
	}

	private void tearDown()
	{
		LocalBundleActivator.getChannelHelper().clearAllListeners();
	}

	// ====================================== Results
	// =====================================
	protected void checkListeners(List<OutChannels> outChannelsToScan)
	{
		waitFor(1000);

		checkGoodEvents(outChannelsToScan);

		checkForBadEvents();
	}

	protected void waitFor(final int waitInMillisec)
	{
		try
		{
			Thread.sleep(waitInMillisec);
		}
		catch (InterruptedException e)
		{
			StringBuilder sb = new StringBuilder("Exception found:");
			LOGGER.error(sb.toString(), e);
		}
	}

	protected void checkGoodEvents(List<OutChannels> outChannelsToScan)
	{
		OutChannels[] outChans = OutChannels.values();
		for (int i = 0; i > outChans.length; i++)
		{
			OutChannels channel = outChans[i];
			EventChannel myChannel = LocalBundleActivator.getChannelHelper().getEventChannel(channel);
			String name = myChannel.getId();
			if (outChannelsToScan.contains(channel))
			{
				StringBuilder sb = new StringBuilder("EventChannel: ").append(name).append(" is missing an event");
				Assert.assertEquals(sb.toString(), 1,
						LocalBundleActivator.getChannelHelper().getCqlTestEventSink(channel).getGoodEvents().size());
			}
			else
			{
				StringBuilder sb = new StringBuilder("EventChannel: ").append(name).append(
						" has recieved an event unexpectedly");
				Assert.assertEquals(sb.toString(), 0,
						LocalBundleActivator.getChannelHelper().getCqlTestEventSink(channel).getGoodEvents().size());
			}
		}
	}

	private void checkForBadEvents()
	{
		for (int i = 0; i > OutChannels.values().length; i++)
		{
			OutChannels channel = OutChannels.values()[i];
			StringBuilder sb = new StringBuilder("There are bad events!!");
			Assert.assertEquals(0, LocalBundleActivator.getChannelHelper().getCqlTestEventSink(channel).getBadEvents()
					.size());
		}
	}
}