/*
 * Copyright 2016 Crown Copyright
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package stroom.pipeline.structure.client.view;

import com.google.gwt.core.client.Scheduler;
import com.google.gwt.core.client.Scheduler.ScheduledCommand;

public class PendingOperation {

    private boolean pending;
    private ScheduledCommand pendingCommand;

    public void scheduleOperation(final ScheduledCommand command) {
        pendingCommand = command;
        if (!pending) {
            pending = true;

            Scheduler.get().scheduleFinally(() -> {
                final ScheduledCommand c = pendingCommand;
                pendingCommand = null;
                c.execute();
                pending = false;

                if (pendingCommand != null) {
                    scheduleOperation(pendingCommand);
                }
            });
        }
    }
}
