/*******************************************************************************
 * Copyright (c) 2008 Chase Technology Ltd - http://www.chasetechnology.co.uk
 * 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
 *
 * Contributors:
 *     Doug Satchwell (Chase Technology Ltd) - initial API and implementation
 *******************************************************************************/

package org.eclipse.wst.xsl.internal.core.tests;

import java.io.IOException;
import java.net.URL;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.Map;

import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;

import junit.framework.TestCase;

import org.apache.xpath.jaxp.XPathFactoryImpl;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IProjectDescription;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IWorkspace;
import org.eclipse.core.resources.IWorkspaceRoot;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.FileLocator;
import org.eclipse.core.runtime.IPath;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.Platform;
import org.eclipse.wst.sse.core.StructuredModelManager;
import org.eclipse.wst.sse.core.internal.provisional.IStructuredModel;
import org.eclipse.wst.xml.core.internal.provisional.document.IDOMModel;
import org.eclipse.wst.xml.core.internal.provisional.document.IDOMNode;
import org.eclipse.wst.xml.core.internal.validation.core.ValidationMessage;
import org.eclipse.wst.xsl.core.XSLCore;
import org.eclipse.wst.xsl.core.internal.model.StylesheetModel;
import org.eclipse.wst.xsl.core.internal.validation.XSLValidationMessage;
import org.eclipse.wst.xsl.core.internal.validation.XSLValidationReport;
import org.eclipse.wst.xsl.core.internal.validation.XSLValidator;
import org.eclipse.wst.xsl.core.tests.XSLCoreTestsPlugin;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

/**
 * An abstract class to help with the testing. 
 * It reads an XSL file, runs the validation on it, and then parses the document looking for comment nodes where the comment starts with ERROR or WARN. 
 * For each comment node found, it determines whether the validation found a corresponding error or warning at the given comment node parent's line number. 
 * It also checks to make sure that no unexpected errors/warnings are found (ones that don't have comment nodes).
 * 
 * @author Doug Satchwell
 */
public abstract class AbstractValidationTest extends TestCase
{
	protected static IProject fTestProject;
	private static boolean fTestProjectInitialized;
	private static final String TEST_PROJECT_NAME = "testproject";

	protected void setUp() throws Exception
	{
		super.setUp();
		if (!fTestProjectInitialized)
		{
			getAndCreateProject();

			// URL installLocation = Platform.getBundle(XSLCoreTestsPlugin.PLUGIN_ID).getEntry("/");
			Enumeration<String> e = Platform.getBundle(XSLCoreTestsPlugin.PLUGIN_ID).getEntryPaths("/projectfiles");// (path, filePattern, recurse)("/projectfiles", null, true);
			while (e.hasMoreElements())
			{
				String path = e.nextElement();
				URL url = Platform.getBundle(XSLCoreTestsPlugin.PLUGIN_ID).getEntry(path);
				if (!url.getFile().endsWith("/"))
				{
					url = FileLocator.resolve(url);
					path = path.substring("projectfiles".length());
					IFile destFile = fTestProject.getFile(path);
					System.out.println(destFile.getLocation()+" --> "+url.toExternalForm());
					destFile.createLink(url.toURI(), IResource.REPLACE, new NullProgressMonitor());
				}
			}
			fTestProject.refreshLocal(IResource.DEPTH_INFINITE, null);
			fTestProjectInitialized = true;
		}
	}
	
	
	protected IFile getFile(String path)
	{
		return fTestProject.getFile(new Path(path));
	}
	
	/**
	 * Validate the file
	 * 
	 * @param file
	 * @return
	 * @throws CoreException
	 * @throws XPathExpressionException
	 * @throws IOException
	 */
	protected XSLValidationReport validate(IFile file) throws CoreException, XPathExpressionException, IOException
	{
		XSLValidationReport report = new XSLValidationReport(file.getLocationURI().toString());
		XSLValidator.getInstance().validate(file,report,true);
		StylesheetModel model = XSLCore.getInstance().getStylesheet(file);		
		assertFalse("Stylesheet model is null",model == null);
		Map<Integer,String> expectedErrors = calculateErrorsAndWarnings(file);
		validateErrors(model,report,expectedErrors);
		return report;
	}
	
	private void validateErrors(StylesheetModel model, XSLValidationReport report, Map<Integer,String> expectedErrors)
	{
		expectedErrors = new HashMap<Integer, String>(expectedErrors);
		for (ValidationMessage msg : report.getValidationMessages())
		{
			XSLValidationMessage error = (XSLValidationMessage)msg;
			assertTrue("Error report must be for the current stylesheet only", error.getNode().getStylesheet() == model.getStylesheet());
			String comment = expectedErrors.remove(error.getLineNumber());
			assertNotNull("Unxpected error at line "+error.getLineNumber()+": "+error,comment);
			assertFalse("Incorrect error level for error at line "+error.getLineNumber()+": "+error,comment.startsWith("ERROR") && msg.getSeverity() != ValidationMessage.SEV_HIGH);
			assertFalse("Incorrect error level for error at line "+error.getLineNumber()+": "+error,comment.startsWith("WARN") && msg.getSeverity() == ValidationMessage.SEV_HIGH);
		}
		for (Map.Entry<Integer, String> entry : expectedErrors.entrySet())
		{	
			assertTrue("Expected error "+entry.getValue()+" at line "+entry.getKey(), false);
		}
	}
	
	private Map<Integer,String> calculateErrorsAndWarnings(IFile file) throws XPathExpressionException, IOException, CoreException
	{
		Map<Integer,String> expectedErrors = new HashMap<Integer,String>();
		IStructuredModel smodel = null;
		try
		{
			smodel = StructuredModelManager.getModelManager().getModelForRead(file);
			if (smodel != null && smodel instanceof IDOMModel)
			{
				IDOMModel model = (IDOMModel) smodel;
				XPathExpression xp = XPathFactoryImpl.newInstance().newXPath().compile("//comment()"); 
				NodeList nodeSet = (NodeList)xp.evaluate(model.getDocument(), XPathConstants.NODESET);
				for (int i=0; i<nodeSet.getLength(); i++)
				{
					Node commentNode = nodeSet.item(i);
					String comment = commentNode.getNodeValue().trim();
					if (comment.startsWith("ERROR") || comment.startsWith("WARN"))
					{
						IDOMNode parent = (IDOMNode)commentNode.getParentNode();
						int line = model.getStructuredDocument().getLineOfOffset(parent.getStartOffset()) + 1;
						expectedErrors.put(line,comment);
					}
				}
			}
		}
		finally
		{
			if (smodel != null)
				smodel.releaseFromRead();
		}
		return expectedErrors;
	}

	private static void getAndCreateProject() throws CoreException
	{
		IWorkspace workspace = getWorkspace();
		IWorkspaceRoot root = workspace.getRoot();
		fTestProject = root.getProject(TEST_PROJECT_NAME);

		createProject(fTestProject, null, null);
		fTestProject.refreshLocal(IResource.DEPTH_INFINITE, null);
		assertTrue(fTestProject.exists());
	}

	private static void createProject(IProject project, IPath locationPath, IProgressMonitor monitor) throws CoreException
	{
		if (monitor == null)
		{
			monitor = new NullProgressMonitor();
		}
		monitor.beginTask("creating test project", 10);
		// create the project
		try
		{
			if (!project.exists())
			{
				IProjectDescription desc = project.getWorkspace().newProjectDescription(project.getName());
				if (Platform.getLocation().equals(locationPath))
				{
					locationPath = null;
				}
				desc.setLocation(locationPath);
				project.create(desc, monitor);
				monitor = null;
			}
			if (!project.isOpen())
			{
				project.open(monitor);
				monitor = null;
			}
		}
		finally
		{
			if (monitor != null)
			{
				monitor.done();
			}
		}
	}

	/**
	 * Returns the workspace instance.
	 */
	public static IWorkspace getWorkspace()
	{
		return ResourcesPlugin.getWorkspace();
	}
}