/*******************************************************************************
 * Copyright (c) 2000, 2011 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
 *******************************************************************************/
package org.eclipse.che.ide.ext.java.jdt.internal.text.correction.proposals;

import org.eclipse.che.ide.ext.java.jdt.Images;
import org.eclipse.che.ide.ext.java.jdt.JavaUIStatus;
import org.eclipse.che.ide.ext.java.jdt.core.dom.CompilationUnit;
import org.eclipse.che.ide.ext.java.jdt.core.dom.rewrite.ASTRewrite;
import org.eclipse.che.ide.ext.java.jdt.core.dom.rewrite.ImportRewrite;
import org.eclipse.che.ide.ext.java.jdt.internal.corext.codemanipulation.StubUtility;
import org.eclipse.che.ide.ext.java.worker.WorkerMessageHandler;
import org.eclipse.che.ide.ext.java.jdt.text.Document;
import org.eclipse.che.ide.ext.java.jdt.text.edits.TextEdit;
import org.eclipse.che.ide.runtime.CoreException;
import org.eclipse.che.ide.runtime.IStatus;


/**
 * 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, ASTRewrite rewrite, int relevance, Document document, Images image) {
        super(name, relevance, document, 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(CompilationUnit astRoot) {
        fImportRewrite = StubUtility.createImportRewrite(document, 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(Document document, TextEdit editRoot) throws CoreException {
        super.addEdits(document, editRoot);
        ASTRewrite rewrite = getRewrite();
        if (rewrite != null) {
            try {
                TextEdit edit = rewrite.rewriteAST(document, WorkerMessageHandler.get().getOptions());
                editRoot.addChild(edit);
            } catch (IllegalArgumentException e) {
                throw new CoreException(JavaUIStatus.createError(IStatus.ERROR, e));
            }
        }
        if (fImportRewrite != null) {
            editRoot.addChild(fImportRewrite.rewriteImports());
        }
    }

    /**
     * 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 = JavaUIStatus.createError(IStatus.ERROR, "Rewriter not initialized", null); //$NON-NLS-1$
            throw new CoreException(status);
        }
        return fRewrite;
    }
}