/*******************************************************************************
 * Copyright (c) 2007, 2008 Oracle. 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:
 *     Oracle - initial API and implementation
 ******************************************************************************/
package org.eclipse.jpt.core.internal.validation;

import java.util.Iterator;
import org.eclipse.core.resources.IMarker;
import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.jpt.core.IResourcePart;
import org.eclipse.jpt.core.JpaProject;
import org.eclipse.jpt.core.JptCorePlugin;
import org.eclipse.jpt.utility.internal.iterators.SingleElementIterator;
import org.eclipse.wst.validation.AbstractValidator;
import org.eclipse.wst.validation.ValidationResult;
import org.eclipse.wst.validation.ValidationState;
import org.eclipse.wst.validation.ValidatorMessage;
import org.eclipse.wst.validation.internal.ValConstants;
import org.eclipse.wst.validation.internal.core.ValidationException;
import org.eclipse.wst.validation.internal.provisional.core.IMessage;
import org.eclipse.wst.validation.internal.provisional.core.IProjectValidationContext;
import org.eclipse.wst.validation.internal.provisional.core.IReporter;
import org.eclipse.wst.validation.internal.provisional.core.IValidationContext;
import org.eclipse.wst.validation.internal.provisional.core.IValidator;

/**
 * This class is referenced in the JPA extension for the
 * WTP validator extension point.
 */
public class JpaValidator extends AbstractValidator implements IValidator {

	
	// ********** IValidator implementation **********

	public void validate(IValidationContext context, IReporter reporter) throws ValidationException {
		validate(reporter, project(context));
	}
	
	public void cleanup(IReporter reporter) {
		// nothing to do
	}
	
	
	// **************** AbstractValidator impl *********************************
	
	@Override
	public ValidationResult validate(IResource resource, int kind, ValidationState state, IProgressMonitor monitor) {
		if (resource.getType() != IResource.FILE)
			return null;
		ValidationResult result = new ValidationResult();
		IReporter reporter = result.getReporter(monitor);
		IProject project = resource.getProject();
		try {
			clearMarkers(project);
		}
		catch (CoreException ce) {
			JptCorePlugin.log(ce);
		}
		result.setSuspendValidation(project);
		validate(reporter, project);
		return result;
	}
	
	
	// **************** internal conv. *****************************************
	
	private void clearMarkers(IProject project) throws CoreException {
		IMarker[] markers = project.findMarkers(ValConstants.ProblemMarker, true, IResource.DEPTH_INFINITE);
		String valId = JptCorePlugin.VALIDATOR_ID;
		for (IMarker marker : markers) {
			String id = marker.getAttribute(ValidatorMessage.ValidationId, null);
			if (valId.equals(id)) marker.delete();
		}
	}
	
	private void validate(IReporter reporter, IProject project) {
		reporter.removeAllMessages(this);
		
		for (Iterator<IMessage> stream = this.validationMessages(project); stream.hasNext(); ) {
			reporter.addMessage(this, adjustMessage(stream.next()));
		}
	}
	
	private IProject project(IValidationContext context) {
		return ((IProjectValidationContext) context).getProject();
	}
	
	private Iterator<IMessage> validationMessages(IProject project) {
		JpaProject jpaProject = JptCorePlugin.getJpaProject(project);
		if (jpaProject != null) {
			return jpaProject.validationMessages();
		}
		return new SingleElementIterator<IMessage>(
			DefaultJpaValidationMessages.buildMessage(
			IMessage.HIGH_SEVERITY,
			JpaValidationMessages.NO_JPA_PROJECT,
			project
		));
	}
	
	private IMessage adjustMessage(IMessage message) {
		IAdaptable targetObject = (IAdaptable) message.getTargetObject();
		IResource targetResource = ((IResourcePart) targetObject.getAdapter(IResourcePart.class)).getResource();
		message.setTargetObject(targetResource);
		if (message.getLineNumber() == IMessage.LINENO_UNSET) {
			message.setAttribute(IMarker.LOCATION, " ");
		}
		return message;
	}
}