/**
    * Copyright 2004-2013 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.kpme.core.service.timezone;
  
  import java.util.List;
  
  import org.apache.commons.lang.StringUtils;
  import org.joda.time.DateTimeZone;
  import org.joda.time.LocalDate;
  import org.kuali.kpme.core.job.Job;
  import org.kuali.kpme.core.location.Location;
  import org.kuali.kpme.core.principal.PrincipalHRAttributes;
  import org.kuali.kpme.core.service.HrServiceLocator;
  import org.kuali.kpme.core.util.HrContext;
  import org.kuali.kpme.core.util.TKUtils;
  import org.kuali.rice.krad.util.GlobalVariables;
  
  public class TimezoneServiceImpl implements TimezoneService {
  
      @Override
      public String getUserTimezone(String principalId) {
          PrincipalHRAttributes principalCalendar = HrServiceLocator.getPrincipalHRAttributeService().getPrincipalCalendar(principalId, LocalDate.now());
          if(principalCalendar != null && principalCalendar.getTimezone() != null){
              return principalCalendar.getTimezone();
          }
          List<Job> jobs = HrServiceLocator.getJobService().getJobs(principalId, LocalDate.now());
          if (jobs.size() > 0) {
              // Grab the location off the first job in the list
              Location location = HrServiceLocator.getLocationService().getLocation(jobs.get(0).getLocation(), LocalDate.now());
              if (location!=null){
                  if(StringUtils.isNotBlank(location.getTimezone())){
                      return location.getTimezone();
                  }
              }
          }
          return TKUtils.getSystemTimeZone();
      }
  
      /**
  	 * Used to determine if an override condition exists for a user timezone
  	 */
  	@Override
  	public String getUserTimezone() {
  		String timezone = "";
  		if (GlobalVariables.getUserSession() != null) {
  			timezone = getUserTimezone(GlobalVariables.getUserSession().getPrincipalId());
  		}
          return timezone;
  	}
  
      @Override
      public DateTimeZone getUserTimezoneWithFallback() {
          String tzid = getUserTimezone();
          if (StringUtils.isEmpty(tzid)) {
              return TKUtils.getSystemDateTimeZone();
          } else {
              return DateTimeZone.forID(tzid);
          }
      }
      
      @Override
      public DateTimeZone getTargetUserTimezoneWithFallback() {
          String tzid = getTargetUserTimezone();
          if (StringUtils.isEmpty(tzid)) {
              return TKUtils.getSystemDateTimeZone();
          } else {
              return DateTimeZone.forID(tzid);
          }
      }
      
      @Override
  	public String getTargetUserTimezone() {
  		String timezone = "";
  		if (GlobalVariables.getUserSession() != null) {
  			// Logic in getTargetPrincipalId returns target principal id if the user is targeting an employee, otherwise returns the current user's id
  			timezone = getUserTimezone(HrContext.getTargetPrincipalId());
  		}
          return timezone;
  	}
      
  	@Override
  	public boolean isSameTimezone() {
  		String userTimezone = getUserTimezone();
  		if(StringUtils.isNotBlank(userTimezone)) {
  			return StringUtils.equals(TKUtils.getSystemTimeZone(), userTimezone);
  		}
 		return true;
 	}
 
 	@Override
 	public String getApproverTimezone(String principalId) {
 		PrincipalHRAttributes principalCalendar = HrServiceLocator.getPrincipalHRAttributeService().getPrincipalCalendar(principalId, LocalDate.now());
 	    if(principalCalendar != null && principalCalendar.getTimezone() != null){
 	        return principalCalendar.getTimezone();
 	    }
 		return TKUtils.getSystemTimeZone();
 	}
 
 }