/**
    * Copyright 2010-2014 The Kuali Foundation
    *
    * Licensed under the Educational Community 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.opensource.org/licenses/ecl2.php
    *
   * 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.kuali.common.util.wait;
  
  import static com.google.common.base.Preconditions.checkState;
  import static java.lang.System.currentTimeMillis;
  import static org.apache.commons.lang3.StringUtils.leftPad;
  import static org.kuali.common.util.base.Threads.sleep;
  import static org.kuali.common.util.log.Loggers.newLogger;
  
  import org.kuali.common.util.FormatUtils;
  import org.kuali.common.util.condition.Condition;
  import org.slf4j.Logger;
  
  public class DefaultWaitService implements WaitService {
  
  	private static final Logger logger = newLogger();
  
  	@Override
  	public WaitResult wait(WaitContext context, Condition condition) {
  		long start = currentTimeMillis();
  		long timeout = start + context.getTimeoutMillis();
  		sleep(context.getInitialPauseMillis());
  		while (!condition.isTrue()) {
  			long now = currentTimeMillis();
  			checkState(now <= timeout, "Timed out waiting");
  			String elapsed = leftPad(FormatUtils.getTime(now - start), 7, " ");
  			String timeoutString = leftPad(FormatUtils.getTime(timeout - now), 7, " ");
  			logger.info("[elapsed: {}  timeout: {}]", elapsed, timeoutString);
  			sleep(context.getSleepMillis());
  		}
  		return WaitResult.create(start, currentTimeMillis());
  	}
  
  }