/*
 * Copyright (c) 2012 Diamond Light Source Ltd.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */

package uk.ac.diamond.scisoft.analysis.rpc;


import org.eclipse.dawnsci.analysis.api.rpc.AnalysisRpcException;
import org.eclipse.dawnsci.analysis.api.rpc.AnalysisRpcRemoteException;
import org.eclipse.dawnsci.analysis.api.rpc.IAnalysisRpcHandler;
import org.junit.AfterClass;
import org.junit.Assert;
import org.junit.BeforeClass;
import org.junit.Test;

public class AnalysisRpcExceptionsTest {

	private static final class CatStringsHandler implements IAnalysisRpcHandler {
		@Override
		public Object run(Object[] unflattened) {
			return (String)unflattened[0] + (String)unflattened[1];
		}
	}

	private static final int PORT = 8614;
	
	private static final String CAT_TWO_STRINGS = "cat";
	private static AnalysisRpcServer analysisRpcServer;
	private static AnalysisRpcClient analysisRpcClient;



	@BeforeClass
	public static void setupBeforeClass() throws AnalysisRpcException {
		analysisRpcServer = new AnalysisRpcServer(PORT);
		analysisRpcServer.start();
		analysisRpcServer.addHandler(CAT_TWO_STRINGS, new CatStringsHandler());
	
		analysisRpcClient = new AnalysisRpcClient(PORT);		
	}
	
	@AfterClass
	public static void tearDownAfterClass() {
		analysisRpcServer.shutdown();
	}

	
	
	@Test
	public void testBasicOperation() throws AnalysisRpcException {
		String result = (String)analysisRpcClient.request(CAT_TWO_STRINGS, new Object[] {"Hello, ", "World!"});
		Assert.assertEquals("Hello, World!", result);
	}
	
	@Test
	public void testHandlerExceptionOperation() {
		// force an ArrayIndexOutOfBoundsException in the handler and make sure it is raised rather than returned
		// due to flattening, it will be raised as an Exception wrapped in an AnalysisRpcException
		try {
			analysisRpcClient.request(CAT_TWO_STRINGS, new Object[] {"Hello, "});
			Assert.fail("No exception raised");
		} catch (AnalysisRpcException e) {
			// The exception type is lost, but we preserve it in the message string
			Assert.assertFalse(e.getCause() instanceof ArrayIndexOutOfBoundsException);
			Assert.assertTrue(e.getCause() instanceof AnalysisRpcRemoteException);
			Assert.assertTrue(e.getCause().getMessage().startsWith("java.lang.ArrayIndexOutOfBoundsException:"));
		}
	}
	
	@Test
	public void testInternalExceptionOperation() {
		// force a flattening exception on the call side
		try {
			analysisRpcClient.request(CAT_TWO_STRINGS, new Object[] {new Object()});
			Assert.fail("No exception raised");
		} catch (AnalysisRpcException e) {			
			Assert.assertEquals(UnsupportedOperationException.class, e.getCause().getClass());
		}
	}
	
	@Test
	public void testNoMatchingHandlerException() {
		// force a not found on the call side error
		try {
			analysisRpcClient.request(CAT_TWO_STRINGS + " invalid", new Object[] {"Hello, ", "World!"});
			Assert.fail("No exception raised");
		} catch (AnalysisRpcException e) {			
			Assert.assertTrue(e.getCause() instanceof AnalysisRpcRemoteException);
			Assert.assertEquals("org.eclipse.dawnsci.analysis.api.rpc.AnalysisRpcException: No handler registered for " + CAT_TWO_STRINGS + " invalid", e.getCause().getMessage());
		}
	}
	
	@Test
	public void testRemoteRaisesException() {
		// have remote code raise an exception and make sure that the stack trace is preserved
		// we don this by forcing a class cast exception (ie cat String + Integer
		try {
			analysisRpcClient.request(CAT_TWO_STRINGS, new Object[] {"Hello, ", 2});
			Assert.fail("No exception raised");
		} catch (AnalysisRpcException e) {			
			Assert.assertTrue(e.getCause().getMessage().startsWith("java.lang.ClassCastException:"));
			StackTraceElement[] remoteStackTrace = e.getCause().getStackTrace();
			Assert.assertEquals(CatStringsHandler.class.getName(), remoteStackTrace[0].getClassName());
			Assert.assertEquals("run", remoteStackTrace[0].getMethodName());
			
		}
	}
}