/*
 * Copyright (c) 2011-2015 EPFL DATA Laboratory
 * Copyright (c) 2014-2015 The Squall Collaboration (see NOTICE)
 *
 * All rights reserved.
 *
 * 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 ch.epfl.data.squall.query_plans;

import java.util.Map;

import ch.epfl.data.squall.components.Component;

/*
 * QueryPlan is for new imperative interface (such as HyracksPlan)
 * Backward-compatible with old interface (which was using only QueryBuilder)
 */
public abstract class QueryPlan {
    private final QueryBuilder _queryBuilder = new QueryBuilder();

    public QueryPlan(String dataPath, String extension, Map conf) {
	build(createQueryPlan(dataPath, extension, conf));
    }

    public QueryPlan() {
    }

    // _queryBuilder expects components in the parent->child order
    // root is the leaf child
    public void build(Component root) {
	if (root == null)
	    return;
	Component[] parents = root.getParents();
	if (parents != null) {
	    for (Component parent : parents) {
		build(parent);
	    }
	}
	_queryBuilder.add(root);
    }

    // This returns the last component: it assumes there is only one last
    // component
    // TODO: put it back to abstract and update plans
    // public abstract Component createQueryPlan(String dataPath, String
    // extension, Map conf);
    public Component createQueryPlan(String dataPath, String extension, Map conf) {
	return null;
    }

    // QueryBuilder is expected from the outside world
    public QueryBuilder getQueryPlan() {
	return _queryBuilder;
    }
}