/** 
 * ============LICENSE_START=======================================================
 * org.onap.aai
 * ================================================================================
 * Copyright © 2017-18 AT&T Intellectual Property. 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.
 * ============LICENSE_END=========================================================
 */

package org.onap.aai.edges;

/**
 * Helper class to produce alphabetized keys for EdgeIngestor and EdgeValidator
 */
public class TypeAlphabetizer {
	/**
	 * Builds key for edge rules, where nodetypes are alphabetically sorted
	 * (ignoring dashes).
	 * 
	 * @param nodeA - first nodetype
	 * @param nodeB - second nodetype
	 * @return {alphabetically first nodetype}|{alphabetically second nodetype}
	 * 		ex: buildAlphabetizedKey("l-interface", "logical-link") -> "l-interface|logical-link"
	 * 			buildAlphabetizedKey("logical-link", "l-interface") -> "l-interface|logical-link"
	 * 
	 * This is alphabetical order to normalize the keys, as sometimes there will be multiple
	 * rules for a pair of node types but the from/to value in the json is flipped for some of them.
	 */
	public String buildAlphabetizedKey(String nodeA, String nodeB) {
		if (nodeA == null) {
			nodeA = "";
		}
		if (nodeB == null) {
			nodeB = "";
		}
		
		//normalize
		String normalizedNodeA = nodeA.replace("-", "");
		String normalizedNodeB = nodeB.replace("-", "");
		int cmp = normalizedNodeA.compareTo(normalizedNodeB);
		
		StringBuilder sb = new StringBuilder();
		if (cmp <= 0) {
			sb.append(nodeA);
			sb.append("|");
			sb.append(nodeB);
		} else {
			sb.append(nodeB);
			sb.append("|");
			sb.append(nodeA);
		}
		return sb.toString();
	}
}