content: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF 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.apache.camel.component.google.calendar;
  
  import java.io.File;
  import java.io.IOException;
  import java.util.Collection;
  
  import com.google.api.client.auth.oauth2.Credential;
  import com.google.api.client.googleapis.auth.oauth2.GoogleCredential;
  import com.google.api.client.googleapis.javanet.GoogleNetHttpTransport;
  import com.google.api.client.http.HttpTransport;
  import com.google.api.client.http.javanet.NetHttpTransport;
  import com.google.api.client.json.jackson2.JacksonFactory;
  import com.google.api.services.calendar.Calendar;
  import org.apache.camel.CamelContext;
  import org.apache.camel.RuntimeCamelException;
  import org.apache.camel.support.ResourceHelper;
  
  public class BatchGoogleCalendarClientFactory implements GoogleCalendarClientFactory {
      private NetHttpTransport transport;
      private JacksonFactory jsonFactory;
  
      public BatchGoogleCalendarClientFactory() {
          this.transport = new NetHttpTransport();
          this.jsonFactory = new JacksonFactory();
      }
  
      @Override
      public Calendar makeClient(
              String clientId, String clientSecret, Collection<String> scopes, String applicationName, String refreshToken,
              String accessToken,
              String emailAddress, String p12FileName, String user) {
          // if emailAddress and p12FileName values are present, assume Google
          // Service Account
          boolean serviceAccount
                  = null != emailAddress && !emailAddress.isEmpty() && null != p12FileName && !p12FileName.isEmpty();
  
          if (!serviceAccount && (clientId == null || clientSecret == null)) {
              throw new IllegalArgumentException("clientId and clientSecret are required to create Google Calendar client.");
          }
  
          try {
              Credential credential;
              if (serviceAccount) {
                  credential = authorizeServiceAccount(emailAddress, p12FileName, scopes, user);
              } else {
                  credential = authorize(clientId, clientSecret);
                  if (refreshToken != null && !refreshToken.isEmpty()) {
                      credential.setRefreshToken(refreshToken);
                  }
                  if (accessToken != null && !accessToken.isEmpty()) {
                      credential.setAccessToken(accessToken);
                  }
              }
              return new Calendar.Builder(transport, jsonFactory, credential).setApplicationName(applicationName).build();
          } catch (Exception e) {
              throw new RuntimeCamelException("Could not create Google Calendar client.", e);
          }
      }
  
      // Authorizes the installed application to access user's protected data.
      private Credential authorize(String clientId, String clientSecret) {
          // authorize
          return new GoogleCredential.Builder()
                  .setJsonFactory(jsonFactory)
                  .setTransport(transport)
                  .setClientSecrets(clientId, clientSecret)
                  .build();
      }
  
      // authorize with P12-Certificate file
      private Credential authorizeServiceAccount(String emailAddress, String p12FileName, Collection<String> scopes, String user)
              throws Exception {
          HttpTransport httpTransport = GoogleNetHttpTransport.newTrustedTransport();
          // set the service account user when provided
          return new GoogleCredential.Builder()
                  .setTransport(httpTransport)
                  .setJsonFactory(jsonFactory)
                  .setServiceAccountId(emailAddress)
                  .setServiceAccountPrivateKeyFromP12File(new File(p12FileName))
                  .setServiceAccountScopes(scopes)
                  .setServiceAccountUser(user)
                  .build();
      }
  
      @Override
      public Calendar makeClient(
              CamelContext camelContext, String serviceAccountKey, Collection<String> scopes, String applicationName,
              String delegate) {
          if (serviceAccountKey == null) {
              throw new IllegalArgumentException("serviceAccountKey is required to create Google Calendar client.");
          }
          try {
              Credential credential = authorizeServiceAccount(camelContext, serviceAccountKey, delegate, scopes);
              return new Calendar.Builder(transport, jsonFactory, credential).setApplicationName(applicationName).build();
          } catch (Exception e) {
              throw new RuntimeCamelException("Could not create Google Calendar client.", e);
          }
      }
  
      // authorize with JSON-Credentials
      private Credential authorizeServiceAccount(
              CamelContext camelContext, String serviceAccountKey, String delegate, Collection<String> scopes) {
          // authorize
          try {
              GoogleCredential cred = GoogleCredential
                      .fromStream(ResourceHelper.resolveMandatoryResourceAsInputStream(camelContext, serviceAccountKey),
                              transport,
                              jsonFactory)
                      .createScoped(scopes != null && !scopes.isEmpty() ? scopes : null).createDelegated(delegate);
              cred.refreshToken();
              return cred;
          } catch (IOException e) {
              throw new RuntimeException(e);
          }
      }
  }
  