/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.brooklyn.util.core.task;

import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ExecutionException;

import org.apache.brooklyn.api.mgmt.Task;

import com.google.common.collect.ImmutableList;


/** runs tasks in order, waiting for one to finish before starting the next; return value here is TBD;
 * (currently is all the return values of individual tasks, but we
 * might want some pipeline support and eventually only to return final value...) */
public class SequentialTask<T> extends CompoundTask<T> {

    public SequentialTask(Object... tasks) { super(tasks); }
    
    public SequentialTask(Map<String,?> flags, Collection<? extends Object> tasks) { super(flags, tasks); }
    public SequentialTask(Collection<? extends Object> tasks) { super(tasks); }
    
    public SequentialTask(Map<String,?> flags, Iterable<? extends Object> tasks) { super(flags, ImmutableList.copyOf(tasks)); }
    public SequentialTask(Iterable<? extends Object> tasks) { super(ImmutableList.copyOf(tasks)); }
    
    protected List<T> runJobs() throws InterruptedException, ExecutionException {
        setBlockingDetails("Executing "+
                (children.size()==1 ? "1 child task" :
                children.size()+" children tasks sequentially") );

        List<T> result = new ArrayList<T>();
        for (Task<? extends T> task : children) {
            submitIfNecessary(task);
            // throw exception (and cancel subsequent tasks) on error
            result.add(task.get());
        }
        return result;
    }
}