/*******************************************************************************
 * Copyright (c) 2009 IBM Corporation and others.
 * 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:
 *     IBM Corporation - initial API and implementation
 *     Zend Technologies
 *******************************************************************************/
package org.eclipse.php.internal.core.codeassist.strategies;

import java.util.*;

import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.dltk.core.*;
import org.eclipse.dltk.core.index2.search.ISearchEngine.MatchRule;
import org.eclipse.dltk.core.search.IDLTKSearchScope;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.php.core.codeassist.ICompletionContext;
import org.eclipse.php.internal.core.codeassist.contexts.NamespaceMemberContext;
import org.eclipse.php.internal.core.model.PHPModelAccess;

public class NamespaceExceptionClassInstantiationStrategy extends NamespaceClassInstantiationStrategy {

	private static final String CORE_PHP = "Core.php"; //$NON-NLS-1$
	private static final String BASIC_PHP = "basic.php"; //$NON-NLS-1$
	private static final String EXCEPTION = "Exception"; //$NON-NLS-1$

	private IType exceptionType;

	public NamespaceExceptionClassInstantiationStrategy(ICompletionContext context) {
		super(context);
	}

	public IType[] getTypes(NamespaceMemberContext context) throws BadLocationException {
		IType exceptionType = getExceptionType();
		if (exceptionType == null)
			return super.getTypes(context);
		List<IType> result = new LinkedList<IType>();
		ITypeHierarchy typeHierarchy;
		ISourceModule sourceModule = context.getSourceModule();
		IScriptProject scriptProject = sourceModule.getScriptProject();
		try {
			if (scriptProject != null) {
				typeHierarchy = exceptionType.newTypeHierarchy(scriptProject, new NullProgressMonitor());
			} else {
				typeHierarchy = exceptionType.newTypeHierarchy(new NullProgressMonitor());
			}

			IType[] classes = typeHierarchy.getAllSubtypes(exceptionType);
			Set<IType> set = new HashSet<IType>();
			set.add(exceptionType);
			set.addAll(Arrays.asList(classes));
			// String prefix = context.getPrefix();
			// if (prefix.trim().length() != 0) {
			IType[] types = super.getTypes(context);
			for (int i = 0; i < types.length; i++) {
				IType type = types[i];
				if (set.contains(type)) {
					result.add(type);
				}
			}
			// } else {
			// result.addAll(set);
			// }

		} catch (ModelException e) {
			return super.getTypes(context);
		}

		return (IType[]) result.toArray(new IType[result.size()]);
	}

	protected IType getExceptionType() {
		if (exceptionType != null)
			return exceptionType;
		IDLTKSearchScope scope = createSearchScope();
		IType[] exceptionTypes = PHPModelAccess.getDefault().findTypes(EXCEPTION, MatchRule.EXACT, 0, 0, scope, null);
		for (int i = 0; i < exceptionTypes.length; i++) {
			if (isExctptionType(exceptionTypes[i])) {
				exceptionType = exceptionTypes[i];
				break;
			}
		}
		return exceptionType;
	}

	private boolean isExctptionType(IType iType) {
		if (EXCEPTION.equals(iType.getElementName()) && (CORE_PHP.equals(iType.getParent().getElementName())
				|| BASIC_PHP.equals(iType.getParent().getElementName())))
			return true;
		return false;
	}
}