content: /*
   * 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 org.accordproject.ergo.runtime;
  
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Set;
  
  import com.google.gson.*;
  
  public class Inheritance {
  	public Inheritance(Map<String, Set<String>> h) {
  		this.inheritance = h;
  	}
  
  	public Inheritance(JsonArray h) {
  		this.inheritance = mkInheritance(h);
  	}
  
  	private static Map<String, Set<String>> mkInheritance(JsonArray h) {
  		final Map<String, Set<String>> res = new HashMap<String, Set<String>>();
  		for(int i = 0; i < h.size(); i ++) {
  			final JsonObject elem = h.get(i).getAsJsonObject();
  			final String sub = elem.get("sub").getAsString();
  			final String sup = elem.get("sup").getAsString();
  			Set<String> parentSet = res.get(sub);
  			if(parentSet == null) {
  				parentSet = new HashSet<String>();
  				res.put(sub, parentSet);
  			}
  			parentSet.add(sup);
  		}
  		return res;
  	}
  
  	/**
  	 * returns true if the child can be safely cast to the parent 
  	 * @param parent the "Parent" brands
  	 * @param child the "Child" brands
  	 * @return
  	 */
  	public boolean isAssignableFrom(Collection<String> parent, Collection<String> child) {
  		PARENT: for (final String oneparent : parent) {
  			for(String onechild : child) {
  				if(onechild.equals(oneparent)) {
  					continue PARENT;
  				}
  				Set<String> childsParents = inheritance.get(onechild);
  				if(childsParents != null && childsParents.contains(oneparent)) {
  					continue PARENT;
  				}
  			}
  			// if no child claims this parent as an ancestor, then we return false
  			return false;
  		}
  	return true;
  	}
  
  	// maps children to parents
  	private Map<String, Set<String>> inheritance;
  }
  