/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package net.sourceforge.phpdt.internal.core;

import net.sourceforge.phpdt.core.IJavaElement;
import net.sourceforge.phpdt.core.IOpenable;
import net.sourceforge.phpdt.core.IPackageFragment;
import net.sourceforge.phpdt.core.JavaModelException;
import net.sourceforge.phpdt.internal.core.util.Util;

import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IFolder;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;

/**
 * This operation deletes a collection of resources and all of their children.
 * It does not delete resources which do not belong to the Java Model (eg GIF
 * files).
 */
public class DeleteResourceElementsOperation extends MultiOperation {
	/**
	 * When executed, this operation will delete the given elements. The
	 * elements to delete cannot be <code>null</code> or empty, and must have
	 * a corresponding resource.
	 */
	protected DeleteResourceElementsOperation(IJavaElement[] elementsToProcess,
			boolean force) {
		super(elementsToProcess, force);
	}

	/**
	 * Deletes the direct children of <code>frag</code> corresponding to its
	 * kind (K_SOURCE or K_BINARY), and deletes the corresponding folder if it
	 * is then empty.
	 */
	private void deletePackageFragment(IPackageFragment frag)
			throws JavaModelException {
		IResource res = frag.getResource();
		if (res != null && res.getType() == IResource.FOLDER) {
			// collect the children to remove
			IJavaElement[] childrenOfInterest = frag.getChildren();
			if (childrenOfInterest.length > 0) {
				IResource[] resources = new IResource[childrenOfInterest.length];
				// remove the children
				for (int i = 0; i < childrenOfInterest.length; i++) {
					resources[i] = childrenOfInterest[i]
							.getCorrespondingResource();
				}
				deleteResources(resources, force);
			}

			// Discard non-java resources
			// Object[] nonJavaResources = frag.getNonJavaResources();
			// int actualResourceCount = 0;
			// for (int i = 0, max = nonJavaResources.length; i < max; i++){
			// if (nonJavaResources[i] instanceof IResource)
			// actualResourceCount++;
			// }
			// IResource[] actualNonJavaResources = new
			// IResource[actualResourceCount];
			// for (int i = 0, max = nonJavaResources.length, index = 0; i <
			// max; i++){
			// if (nonJavaResources[i] instanceof IResource)
			// actualNonJavaResources[index++] = (IResource)nonJavaResources[i];
			// }
			// deleteResources(actualNonJavaResources, fForce);

			// delete remaining files in this package (.class file in the case
			// where Proj=src=bin)
			IResource[] remainingFiles;
			try {
				remainingFiles = ((IFolder) res).members();
			} catch (CoreException ce) {
				throw new JavaModelException(ce);
			}
			boolean isEmpty = true;
			for (int i = 0, length = remainingFiles.length; i < length; i++) {
				IResource file = remainingFiles[i];
				if (file instanceof IFile) {
					this.deleteResource(file, IResource.FORCE
							| IResource.KEEP_HISTORY);
				} else {
					isEmpty = false;
				}
			}
			if (isEmpty) {
				// delete recursively empty folders
				IResource fragResource = frag.getResource();
				if (fragResource != null) {
					deleteEmptyPackageFragment(frag, false, fragResource
							.getParent());
				}
			}
		}
	}

	/**
	 * @see MultiOperation
	 */
	protected String getMainTaskName() {
		return Util.bind("operation.deleteResourceProgress"); //$NON-NLS-1$
	}

	/**
	 * @see MultiOperation. This method delegate to <code>deleteResource</code>
	 *      or <code>deletePackageFragment</code> depending on the type of
	 *      <code>element</code>.
	 */
	protected void processElement(IJavaElement element)
			throws JavaModelException {
		switch (element.getElementType()) {
		case IJavaElement.CLASS_FILE:
		case IJavaElement.COMPILATION_UNIT:
			deleteResource(element.getResource(), force ? IResource.FORCE
					| IResource.KEEP_HISTORY : IResource.KEEP_HISTORY);
			break;
		case IJavaElement.PACKAGE_FRAGMENT:
			deletePackageFragment((IPackageFragment) element);
			break;
		default:
			throw new JavaModelException(new JavaModelStatus(
					JavaModelStatus.INVALID_ELEMENT_TYPES, element));
		}
		// ensure the element is closed
		if (element instanceof IOpenable) {
			((IOpenable) element).close();
		}
	}

	/**
	 * @see MultiOperation
	 */
	protected void verify(IJavaElement element) throws JavaModelException {
		if (element == null || !element.exists())
			error(JavaModelStatus.ELEMENT_DOES_NOT_EXIST, element);

		int type = element.getElementType();
		if (type <= IJavaElement.PACKAGE_FRAGMENT_ROOT
				|| type > IJavaElement.COMPILATION_UNIT)
			error(JavaModelStatus.INVALID_ELEMENT_TYPES, element);
		// else if (type == IJavaElement.PACKAGE_FRAGMENT && element instanceof
		// JarPackageFragment)
		// error(JavaModelStatus.INVALID_ELEMENT_TYPES, element);
		IResource resource = element.getResource();
		if (resource instanceof IFolder) {
			if (resource.isLinked()) {
				error(JavaModelStatus.INVALID_RESOURCE, element);
			}
		}
	}
}
