/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you 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://opensource.org/licenses/ecl2.txt
   *
   * 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.opencastproject.smil.impl;
  
  import org.opencastproject.smil.api.SmilException;
  import org.opencastproject.smil.api.SmilResponse;
  import org.opencastproject.smil.entity.SmilImpl;
  import org.opencastproject.smil.entity.SmilObjectImpl;
  import org.opencastproject.smil.entity.api.Smil;
  import org.opencastproject.smil.entity.api.SmilObject;
  import org.opencastproject.util.XmlSafeParser;
  
  import org.apache.commons.io.IOUtils;
  import org.xml.sax.SAXException;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.StringWriter;
  
  import javax.xml.bind.JAXBContext;
  import javax.xml.bind.JAXBException;
  import javax.xml.bind.Marshaller;
  import javax.xml.bind.Unmarshaller;
  import javax.xml.bind.annotation.XmlAccessType;
  import javax.xml.bind.annotation.XmlAccessorType;
  import javax.xml.bind.annotation.XmlElement;
  import javax.xml.bind.annotation.XmlElementRef;
  import javax.xml.bind.annotation.XmlRootElement;
  
  /**
   * {@link SmilResponse} implementation.
   */
  @XmlAccessorType(XmlAccessType.NONE)
  @XmlRootElement(name = "smil-response", namespace = "http://smil.opencastproject.org")
  public class SmilResponseImpl implements SmilResponse {
  
    /**
     * Smil
     */
    private Smil smil;
    /**
     * Entities
     */
    private SmilObject[] entities;
  
    /**
     * Empty constructor (needed for JAXB).
     */
    private SmilResponseImpl() {
      smil = null;
      entities = null;
    }
  
    /**
     * Constructor
     *
     * @param smil to set
     */
    public SmilResponseImpl(Smil smil) {
      this(smil, new SmilObject[]{});
    }
  
    /**
     * Constructor.
     *
     * @param smil to set
     * @param entity to set
     */
    public SmilResponseImpl(Smil smil, SmilObject entity) {
      this(smil, new SmilObject[]{entity});
    }
  
    /**
     * Constructor.
     *
     * @param smil to set
     * @param entities to set
     */
    public SmilResponseImpl(Smil smil, SmilObject[] entities) {
      this.smil = smil;
     this.entities = entities;
   }
 
   /**
    * {@inheritDoc }
    */
   @XmlElement(type = SmilImpl.class, required = true)
   @Override
   public Smil getSmil() {
     return smil;
   }
 
   /**
    * Set {@link Smil}.
    *
    * @param smil to set
    */
   private void setSmil(Smil smil) {
     this.smil = smil;
   }
 
   /**
    * {@inheritDoc }
    */
   @Override
   public int getEntitiesCount() {
     if (entities == null) {
       return 0;
     } else {
       return entities.length;
     }
   }
 
   /**
    * {@inheritDoc }
    */
   @Override
   public SmilObject getEntity() throws SmilException {
     if (entities.length == 0) {
       throw new SmilException("There is no entity.");
     }
     if (entities.length > 1) {
       throw new SmilException("There is more than one entity.");
     }
     return entities[0];
   }
 
   /**
    * {@inheritDoc }
    */
   @Override
   public SmilObject[] getEntities() throws SmilException {
     if (entities.length == 0) {
       throw new SmilException("There are no entities.");
     }
     return entities;
   }
 
   /**
    * {@inheritDoc }
    */
   @Override
   public String toXml() throws JAXBException {
     StringWriter writer = new StringWriter();
     JAXBContext ctx = JAXBContext.newInstance(SmilResponseImpl.class);
     Marshaller marshaller = ctx.createMarshaller();
     // marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);
     marshaller.marshal(this, writer);
     return writer.toString();
   }
 
   /**
    * Deserialize {@link SmilResponse} from XML.
    *
    * @param smilResponseXml {@link SmilResponse} as XML
    * @return {@link SmilResponse} object
    * @throws JAXBException if deserialization fail
    */
   public static SmilResponse fromXml(String smilResponseXml) throws JAXBException {
     InputStream smilStream = IOUtils.toInputStream(smilResponseXml);
     try {
       return fromXml(smilStream);
     } finally {
       IOUtils.closeQuietly(smilStream);
     }
   }
 
   /**
    * Deserialize {@link SmilResponse} from XML.
    *
    * @param smilResponseXml {@link SmilResponse} as XML {@link InputStream}
    * @return {@link SmilResponse} object
    * @throws JAXBException if deserialization fail
    */
   protected static SmilResponse fromXml(InputStream smilResponseXml) throws JAXBException {
     JAXBContext ctx = JAXBContext.newInstance(SmilResponseImpl.class);
     Unmarshaller unmarshaller = ctx.createUnmarshaller();
     try {
       return (SmilResponse) unmarshaller.unmarshal(XmlSafeParser.parse(smilResponseXml));
     } catch (IOException | SAXException e) {
       throw new JAXBException(e);
     }
 
   }
 
   /**
    * JAXB helper method.
    *
    * @return
    */
   @XmlElementRef
   private SmilResponseEntity<SmilObject>[] getResponseEntities() {
     SmilResponseEntity[] entitiesWrapped = new SmilResponseEntity[entities.length];
     for (int i = 0; i < entities.length; i++) {
       entitiesWrapped[i] = new SmilResponseEntity(entities[i]);
     }
     return entitiesWrapped;
   }
 
   /**
    * JAXB helper method.
    *
    * @param entities
    */
   private void setResponseEntities(SmilResponseEntity<SmilObject>[] entities) {
     this.entities = new SmilObject[entities.length];
     for (int e = 0; e < entities.length; e++) {
       this.entities[e] = entities[e].getEntity();
     }
   }
 
   /**
    * {@link SmilObject} wrapper class for serialization.
    *
    * @param <SmilObject>
    */
   @XmlRootElement(name = "entity", namespace = "http://smil.opencastproject.org")
   private static class SmilResponseEntity<SmilObject> {
 
     private SmilObject entity;
 
     SmilResponseEntity() {
     }
 
     SmilResponseEntity(SmilObject entity) {
       this.entity = entity;
     }
 
     @XmlElementRef(type = SmilObjectImpl.class)
     public SmilObject getEntity() {
       return entity;
     }
 
     private void setEntity(SmilObject entity) {
       this.entity = entity;
     }
   }
 }