/*
    * Copyright 2012-2013 the original author or authors.
    *
    * 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
    *
    *      https://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.springframework.security.oauth2.provider.approval;
  
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashSet;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.concurrent.ConcurrentMap;
  
  /**
   * @author Dave Syer
   * 
   */
  public class InMemoryApprovalStore implements ApprovalStore {
  
  	private ConcurrentMap<Key, Collection<Approval>> map = new ConcurrentHashMap<Key, Collection<Approval>>();
  
  	@Override
  	public boolean addApprovals(Collection<Approval> approvals) {
  		for (Approval approval : approvals) {
  			Collection<Approval> collection = getApprovals(approval);
  			collection.add(approval);
  		}
  		return true;
  	}
  
  	@Override
  	public boolean revokeApprovals(Collection<Approval> approvals) {
  		boolean success = true;
  		for (Approval approval : approvals) {
  			Collection<Approval> collection = getApprovals(approval);
  			boolean removed = collection.remove(approval);
  			if (!removed) {
  				success = false;
  			}
  		}
  		return success;
  	}
  
  	private Collection<Approval> getApprovals(Approval approval) {
  		Key key = new Key(approval.getUserId(), approval.getClientId());
  		if (!map.containsKey(key)) {
  			map.putIfAbsent(key, new HashSet<Approval>());
  		}
  		return map.get(key);
  	}
  
  	@Override
  	public Collection<Approval> getApprovals(String userId, String clientId) {
  		Approval approval = new Approval();
  		approval.setUserId(userId);
  		approval.setClientId(clientId);
  		return Collections.unmodifiableCollection(getApprovals(approval));
  	}
  	
  	public void clear() {
  		map.clear();
  	}
  
  	private static class Key {
  
  		String userId;
  
  		String clientId;
  
  		public Key(String userId, String clientId) {
  			this.userId = userId;
  			this.clientId = clientId;
  		}
  
  		@Override
  		public int hashCode() {
  			final int prime = 31;
  			int result = 1;
  			result = prime * result + ((clientId == null) ? 0 : clientId.hashCode());
  			result = prime * result + ((userId == null) ? 0 : userId.hashCode());
  			return result;
  		}
  
  		@Override
  		public boolean equals(Object obj) {
  			if (this == obj)
  				return true;
  			if (obj == null)
 				return false;
 			if (getClass() != obj.getClass())
 				return false;
 			Key other = (Key) obj;
 			if (clientId == null) {
 				if (other.clientId != null)
 					return false;
 			}
 			else if (!clientId.equals(other.clientId))
 				return false;
 			if (userId == null) {
 				if (other.userId != null)
 					return false;
 			}
 			else if (!userId.equals(other.userId))
 				return false;
 			return true;
 		}
 
 	}
 
 }