/*******************************************************************************
 * Copyright (c) 2006 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
 * Port to the D programming language:
 *     Frank Benoit <benoit@tionex.de>
 *******************************************************************************/
module org.eclipse.core.commands.operations.IAdvancedUndoableOperation2;

import org.eclipse.core.commands.ExecutionException;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;

import java.lang.all;

/**
 * <p>
 * IAdvancedUndoableOperation2 defines a method for computing the validity of
 * executing an operation before attempting to execute it. It also defines a way
 * for clients to specify that computing status should be done quietly, without
 * consulting the user. This interface is useful when implementing
 * {@link IOperationApprover2}, or any other object that performs validation of
 * the undo history. It also allows operations to specify whether they should be
 * run in the UI thread.
 * </p>
 *
 * @since 3.3
 *
 */
public interface IAdvancedUndoableOperation2 {
    /**
     * Return a status indicating the projected outcome of executing the
     * receiver.
     *
     * This method should be used to report the possible outcome of executing an
     * operation when computing the validity of an execute is too expensive to
     * perform in {@link IUndoableOperation#canExecute()}. It is not called by
     * the operation history, but instead is used by clients (such as
     * implementers of {@link IOperationApprover2}) who wish to perform
     * advanced validation of an operation before attempting to execute it.
     *
     * If the result of this method is the discovery that an operation can in
     * fact not be executed, then the operation is expected to correctly answer
     * <code>false</code> on subsequent calls to
     * {@link IUndoableOperation#canExecute()}.
     *
     * @param monitor
     *            the progress monitor (or <code>null</code>) to use for
     *            reporting progress to the user while computing the validity.
     *
     * @return the IStatus indicating the validity of the execute. The status
     *         severity should be set to <code>OK</code> if the execute can
     *         successfully be performed, and <code>ERROR</code> if it cannot.
     *         Any other severity is assumed to represent an ambiguous state.
     * @throws ExecutionException
     *             if an exception occurs while computing the validity.
     */
    IStatus computeExecutionStatus(IProgressMonitor monitor);

    /**
     * Set a bool that instructs whether the computation of the receiver's
     * execution, undo, or redo status should quietly compute status without
     * consulting or prompting the user. The default value is <code>false</code>.
     * This flag should only be set to <code>true</code> while the execution,
     * undo, or redo status computations are being performed in the background,
     * and should be restored to <code>false</code> when complete.
     * <p>
     * If the status computation methods typically need to consult the user in
     * order to determine the severity of a particular situation, the least
     * severe status that could be chosen by the user should be returned when
     * this flag is <code>true</code>. This can help to prevent overzealous
     * disposal of the operation history when an operation is in an ambiguous
     * state. Typically, the status computation methods are invoked with this
     * flag set to <code>false</code> just before the actual execution, undo,
     * or redo occurs, so the user can be consulted for the final outcome.
     *
     * @param quiet
     *            <code>true</code> if it is inappropriate to consult or
     *            otherwise prompt the user while computing status, and
     *            <code>false</code> if the user may be prompted.
     *
     * @see #computeExecutionStatus(IProgressMonitor)
     * @see IAdvancedUndoableOperation#computeUndoableStatus(IProgressMonitor)
     * @see IAdvancedUndoableOperation#computeRedoableStatus(IProgressMonitor)
     */
    public void setQuietCompute(bool quiet);

    /**
     * Return a bool that instructs whether the operation should be executed,
     * undone, or redone in a background thread.
     *
     * @return <code>true</code> if the operation should be run in the
     *         background, <code>false</code> if it should not.
     */
    public bool runInBackground();
}