/**
    *
    * Copyright (C) 2011 Cloud Conscious, LLC. <info@cloudconscious.com>
    *
    * ====================================================================
    * 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
    *
   * 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.ec2.xml;
  
  import static org.jclouds.util.SaxUtils.currentOrNull;
  import static org.jclouds.util.SaxUtils.equalsOrSuffix;
  
  import java.util.Date;
  import java.util.Set;
  
  import javax.annotation.Resource;
  import javax.inject.Inject;
  
  import org.jclouds.aws.util.AWSUtils;
  import org.jclouds.date.DateService;
  import org.jclouds.ec2.domain.Attachment;
  import org.jclouds.ec2.domain.BlockDevice;
  import org.jclouds.ec2.domain.InstanceState;
  import org.jclouds.ec2.domain.Reservation;
  import org.jclouds.ec2.domain.RootDeviceType;
  import org.jclouds.ec2.domain.RunningInstance;
  import org.jclouds.ec2.domain.RunningInstance.Builder;
  import org.jclouds.http.functions.ParseSax.HandlerForGeneratedRequestWithResult;
  import org.jclouds.location.Region;
  import org.jclouds.logging.Logger;
  import org.xml.sax.Attributes;
  
  import com.google.common.collect.Sets;
  import com.google.inject.Provider;
  
  /**
   * 
   * @author Adrian Cole
   */
  public abstract class BaseReservationHandler<T> extends HandlerForGeneratedRequestWithResult<T> {
  
     @Resource
     protected Logger logger = Logger.NULL;
  
     protected final DateService dateService;
     protected final String defaultRegion;
     protected final Provider<Builder> builderProvider;
  
     @Inject
     public BaseReservationHandler(DateService dateService, @Region String defaultRegion,
           Provider<RunningInstance.Builder> builderProvider) {
        this.dateService = dateService;
        this.defaultRegion = defaultRegion;
        this.builderProvider = builderProvider;
        this.builder = builderProvider.get();
     }
  
     protected StringBuilder currentText = new StringBuilder();
  
     protected Builder builder;
  
     protected int itemDepth;
     boolean inInstancesSet;
     // attachments
     private String volumeId;
     private Attachment.Status attachmentStatus;
     private Date attachTime;
     private boolean deleteOnTermination;
     private String deviceName;
  
     // reservation stuff
     private Set<String> groupIds = Sets.newLinkedHashSet();
     private String ownerId;
     private String requesterId;
     private String reservationId;
  
     private Set<RunningInstance> instances = Sets.newLinkedHashSet();
  
     public void startElement(String uri, String name, String qName, Attributes attrs) {
        if (equalsOrSuffix(qName, "item")) {
           itemDepth++;
        } else if (equalsOrSuffix(qName, "instancesSet")) {
           inInstancesSet = true;
        }
     }
  
     public void endElement(String uri, String name, String qName) {
        if (equalsOrSuffix(qName, "item")) {
          inItem();
          itemDepth--;
       } else if (equalsOrSuffix(qName, "instancesSet")) {
          inInstancesSet = false;
       } else if (equalsOrSuffix(qName, "groupId")) {
          groupIds.add(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "ownerId")) {
          ownerId = currentOrNull(currentText);
       } else if (equalsOrSuffix(qName, "requesterId")) {
          requesterId = currentOrNull(currentText);
       } else if (equalsOrSuffix(qName, "reservationId")) {
          reservationId = currentOrNull(currentText);
       } else if (equalsOrSuffix(qName, "amiLaunchIndex")) {
          builder.amiLaunchIndex(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "dnsName")) {
          String dnsName = currentOrNull(currentText);
          // Eucalyptus
          if (!"0.0.0.0".equals(dnsName))
             builder.dnsName(dnsName);
       } else if (equalsOrSuffix(qName, "imageId")) {
          builder.imageId(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "instanceId")) {
          builder.instanceId(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "name")) {
          builder.instanceState(InstanceState.fromValue(currentOrNull(currentText)));
       } else if (equalsOrSuffix(qName, "instanceType")) {
          builder.instanceType(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "ipAddress")) {
          builder.ipAddress(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "kernelId")) {
          builder.kernelId(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "keyName")) {
          builder.keyName(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "launchTime")) {
          builder.launchTime(parseDate());
       } else if (equalsOrSuffix(qName, "availabilityZone")) {
          builder.availabilityZone(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "virtualizationType")) {
          builder.virtualizationType(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "platform")) {
          builder.platform(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "privateDnsName")) {
          String privateDnsName = currentOrNull(currentText);
          // Eucalyptus
          if (!"0.0.0.0".equals(privateDnsName))
             builder.privateDnsName(privateDnsName);
       } else if (equalsOrSuffix(qName, "privateIpAddress")) {
          builder.privateIpAddress(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "ramdiskId")) {
          builder.ramdiskId(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "reason")) {
          builder.reason(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "rootDeviceType")) {
          builder.rootDeviceType(RootDeviceType.fromValue(currentOrNull(currentText)));
       } else if (equalsOrSuffix(qName, "rootDeviceName")) {
          builder.rootDeviceName(currentOrNull(currentText));
       } else if (equalsOrSuffix(qName, "deviceName")) {
          deviceName = currentOrNull(currentText);
       } else if (equalsOrSuffix(qName, "volumeId")) {
          volumeId = currentOrNull(currentText);
       } else if (equalsOrSuffix(qName, "status")) {
          attachmentStatus = Attachment.Status.fromValue(currentText.toString().trim());
       } else if (equalsOrSuffix(qName, "attachTime")) {
          attachTime = dateService.iso8601DateParse(currentText.toString().trim());
       } else if (equalsOrSuffix(qName, "deleteOnTermination")) {
          deleteOnTermination = Boolean.parseBoolean(currentText.toString().trim());
       } else if (equalsOrSuffix(qName, "ebs")) {
          builder.device(deviceName, new BlockDevice(volumeId, attachmentStatus, attachTime, deleteOnTermination));
          this.deviceName = null;
          this.volumeId = null;
          this.attachmentStatus = null;
          this.attachTime = null;
          this.deleteOnTermination = true;
       }
       currentText = new StringBuilder();
    }
 
    protected Date parseDate() {
       try {
          return dateService.iso8601DateParse(currentOrNull(currentText));
       } catch (RuntimeException e) {
          // Eucalyptus
          return dateService.iso8601SecondsDateParse(currentOrNull(currentText));
       }
    }
 
    protected void inItem() {
       if (endOfInstanceItem()) {
          refineBuilderBeforeAddingInstance();
          instances.add(builder.build());
          builder = builderProvider.get();
       }
    }
 
    protected void refineBuilderBeforeAddingInstance() {
       String region = getRequest() != null ? AWSUtils.findRegionInArgsOrNull(getRequest()) : null;
 
       // Eucalyptus
       if (builder.getIpAddress() == null && builder.getDnsName() != null && builder.getDnsName().matches(".*[0-9]$")) {
          builder.ipAddress(builder.getDnsName());
          builder.dnsName(null);
       }
       if (builder.getPrivateIpAddress() == null && builder.getPrivateDnsName() != null
             && builder.getPrivateDnsName().matches(".*[0-9]$")) {
          builder.privateIpAddress(builder.getPrivateDnsName());
          builder.privateDnsName(null);
       }
 
       builder.region((region == null) ? defaultRegion : region);
       builder.groupIds(groupIds);
    }
 
    protected Builder builder() {
       return builder;
    }
 
    protected boolean endOfInstanceItem() {
       return itemDepth <= 2 && inInstancesSet;
    }
 
    public void characters(char ch[], int start, int length) {
       currentText.append(ch, start, length);
    }
 
    protected Reservation<? extends RunningInstance> newReservation() {
       String region = getRequest() != null ? AWSUtils.findRegionInArgsOrNull(getRequest()) : null;
       if (region == null)
          region = defaultRegion;
       Reservation<? extends RunningInstance> info = new Reservation<RunningInstance>(region, groupIds, instances,
             ownerId, requesterId, reservationId);
       this.groupIds = Sets.newLinkedHashSet();
       this.instances = Sets.newLinkedHashSet();
       this.ownerId = null;
       this.requesterId = null;
       this.reservationId = null;
       return info;
    }
 
 }