/**
 * Licensed to jclouds, Inc. (jclouds) under one or more
 * contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  jclouds 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.jclouds.util;

import static com.google.common.base.Preconditions.checkNotNull;

import org.jclouds.javax.annotation.Nullable;

import org.jclouds.crypto.Pems;
import org.jclouds.domain.Credentials;


/**
 * 
 * 
 * @author Adrian Cole
 */
public class CredentialUtils {

   public static Credentials overrideCredentialsIfSupplied(Credentials defaultCredentials,
         @Nullable Credentials overridingCredentials) {
      if (overridingCredentials == null)
         return defaultCredentials;
      String identity = overridingCredentials.identity != null ? overridingCredentials.identity : checkNotNull(
            defaultCredentials, "defaultCredentials").identity;
      String credential = overridingCredentials.credential != null ? overridingCredentials.credential : checkNotNull(
            defaultCredentials, "defaultCredentials").credential;
   
      return new Credentials(identity, credential);
   }

   public static boolean isPrivateKeyCredential(Credentials credentials) {
      return credentials != null && isPrivateKeyCredential(credentials.credential);
   }

   public static boolean isPrivateKeyCredential(String credential) {
      return credential != null
            && (credential.startsWith(Pems.PRIVATE_PKCS1_MARKER) || credential.startsWith(Pems.PRIVATE_PKCS8_MARKER));
   }

   public static boolean isPrivateKeyEncrypted(byte[] privateKey) {
      return new String(privateKey).contains("Proc-Type: 4,ENCRYPTED");
   }

}
