/*******************************************************************************
 * 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.ui.text.correction.proposals;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.dltk.core.ISourceModule;
import org.eclipse.dltk.internal.ui.DLTKUIStatus;
import org.eclipse.jface.text.IDocument;
import org.eclipse.php.core.ast.nodes.Program;
import org.eclipse.php.internal.core.ast.rewrite.ASTRewrite;
import org.eclipse.php.internal.core.ast.rewrite.ImportRewrite;
import org.eclipse.swt.graphics.Image;
import org.eclipse.text.edits.TextEdit;

/**
 * A proposal for quick fixes and quick assists that works on a AST rewriter.
 * Either a rewriter is directly passed in the constructor or method
 * {@link #getRewrite()} is overridden to provide the AST rewriter that is
 * evaluated to the document when the proposal is applied.
 * 
 * @since 3.2
 */
public class ASTRewriteCorrectionProposal extends CUCorrectionProposal {

	private ASTRewrite fRewrite;

	private ImportRewrite fImportRewrite;

	/**
	 * Constructs a AST rewrite correction proposal.
	 * 
	 * @param name
	 *            the display name of the proposal.
	 * @param cu
	 *            the compilation unit that is modified.
	 * @param rewrite
	 *            the AST rewrite that is invoked when the proposal is applied
	 *            or <code>null</code> if {@link #getRewrite()} is overridden.
	 * @param relevance
	 *            The relevance of this proposal.
	 * @param image
	 *            The image that is displayed for this proposal or
	 *            <code>null</code> if no image is desired.
	 */
	public ASTRewriteCorrectionProposal(String name, ISourceModule cu, ASTRewrite rewrite, int relevance, Image image) {
		super(name, cu, relevance, image);
		fRewrite = rewrite;
	}

	/**
	 * Returns the import rewriter used for this compilation unit. <code>
	 * 
	 * @return the import rewriter or <code>null</code> if no import rewriter is
	 *         set
	 */
	public ImportRewrite getImportRewrite() {
		return fImportRewrite;
	}

	/**
	 * Sets the import rewriter used for this compilation unit.
	 * 
	 * @param rewrite
	 *            the import rewriter
	 */
	public void setImportRewrite(ImportRewrite rewrite) {
		fImportRewrite = rewrite;
	}

	/**
	 * Sets the import rewriter used for this compilation unit.
	 * 
	 * @param astRoot
	 *            the AST for the current CU
	 * @return returns the create import rewriter
	 */
	public ImportRewrite createImportRewrite(Program astRoot) {
		fImportRewrite = ImportRewrite.create(astRoot, true);
		return fImportRewrite;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.jdt.internal.ui.text.correction.CUCorrectionProposal#addEdits
	 * (org.eclipse.jface.text.IDocument)
	 */
	@Override
	protected void addEdits(IDocument document, TextEdit editRoot) throws CoreException {
		super.addEdits(document, editRoot);
		ASTRewrite rewrite = getRewrite();
		if (rewrite != null) {
			try {
				TextEdit edit = rewrite.rewriteAST(document, null);
				editRoot.addChild(edit);
			} catch (IllegalArgumentException e) {
				throw new CoreException(DLTKUIStatus.createError(IStatus.ERROR, e));
			}
		}
		if (fImportRewrite != null) {
			editRoot.addChild(fImportRewrite.rewriteImports(new NullProgressMonitor()));
		}
	}

	/**
	 * Returns the rewriter that has been passed in the constructor.
	 * Implementors can override this method to create the rewriter lazy. This
	 * method will only be called once.
	 * 
	 * @return returns the rewriter to be used.
	 * @throws CoreException
	 *             an exception is thrown when the rewriter could not be
	 *             created.
	 */
	protected ASTRewrite getRewrite() throws CoreException {
		if (fRewrite == null) {
			IStatus status = DLTKUIStatus.createError(IStatus.ERROR, Messages.ASTRewriteCorrectionProposal_0, null);
			throw new CoreException(status);
		}
		return fRewrite;
	}
}