VariableConverter.java

/*
 * Copyright (c) 2017 OBiBa. All rights reserved.
 *
 * This program and the accompanying materials
 * are made available under the terms of the GNU Public License v3.0.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package org.obiba.magma.xstream.converter;

import org.obiba.magma.Attribute;
import org.obiba.magma.Category;
import org.obiba.magma.ValueType;
import org.obiba.magma.Variable;

import com.thoughtworks.xstream.converters.MarshallingContext;
import com.thoughtworks.xstream.converters.UnmarshallingContext;
import com.thoughtworks.xstream.io.HierarchicalStreamReader;
import com.thoughtworks.xstream.io.HierarchicalStreamWriter;
import com.thoughtworks.xstream.mapper.Mapper;

/**
 * Converts an {@code Variable} instance.
 * <p/>
 * Resulting XML:
 * <p/>
 * <pre>
 * <variable name="HQ.SMOKER" valueType="text" entityType="Participant">
 *   <attributes>
 *     <attribute name="label" valueType="text" locale="en">
 *       <value>Do you smoke?</value>
 *     </attribute>
 *     <attribute name="label" valueType="text" locale="fr">
 *       <value>Fumez-vous?</value>
 *     </attribute>
 *     ...
 *   </attributes>
 *   <categories>
 *     <category name="YES" code="1">
 *       <attributes>
 *         <attribute name="label" valueType="text" locale="en">
 *           <value>Yes</value>
 *         </attribute>
 *         <attribute name="label" valueType="text" locale="fr">
 *           <value>Oui</value>
 *         </attribute>
 *       </attributes>
 *     </category>
 *     ...
 *   </categories>
 * </variable>
 * </pre>
 */
public class VariableConverter extends AbstractAttributeAwareConverter {

  public VariableConverter(Mapper mapper) {
    super(mapper);
  }

  @Override
  @SuppressWarnings({ "unchecked", "rawtypes" })
  public boolean canConvert(Class type) {
    return Variable.class.isAssignableFrom(type);
  }

  @Override
  public void marshal(Object source, HierarchicalStreamWriter writer, MarshallingContext context) {
    Variable variable = (Variable) source;
    writer.addAttribute("name", variable.getName());
    writer.addAttribute("valueType", variable.getValueType().getName());
    writer.addAttribute("entityType", variable.getEntityType());

    if(variable.getUnit() != null) {
      writer.addAttribute("unit", variable.getUnit());
    }

    if(variable.getMimeType() != null) {
      writer.addAttribute("mimeType", variable.getMimeType());
    }

    if(variable.getReferencedEntityType()!= null) {
      writer.addAttribute("referencedEntityType", variable.getReferencedEntityType());
    }

    writer.addAttribute("index", Integer.toString(variable.getIndex()));

    if(variable.isRepeatable()) {
      writer.addAttribute("repeatable", "true");
      if(variable.getOccurrenceGroup() != null) {
        writer.addAttribute("occurrenceGroup", variable.getOccurrenceGroup());
      }
    }
    marshallAttributes(variable, writer, context);
    marshallCategories(variable, writer, context);
  }

  @Override
  public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext context) {
    Variable.Builder builder = Variable.Builder
        .newVariable(reader.getAttribute("name"), ValueType.Factory.forName(reader.getAttribute("valueType")),
            reader.getAttribute("entityType"));
    if(reader.getAttribute("repeatable") != null) {
      try {
        if (Boolean.parseBoolean(reader.getAttribute("repeatable"))) {
          builder.repeatable().occurrenceGroup(reader.getAttribute("occurrenceGroup"));
        }
      } catch(Exception e) {}
    }
    if(reader.getAttribute("unit") != null) {
      builder.unit(reader.getAttribute("unit"));
    }
    if(reader.getAttribute("mimeType") != null) {
      builder.mimeType(reader.getAttribute("mimeType"));
    }
    if(reader.getAttribute("referencedEntityType") != null) {
      builder.referencedEntityType(reader.getAttribute("referencedEntityType"));
    }
    if(reader.getAttribute("index") != null) {
      builder.index(reader.getAttribute("index"));
    }
    unmarshalChildren(reader, context, builder);

    return builder.build();
  }

  private void unmarshalChildren(HierarchicalStreamReader reader, UnmarshallingContext context,
      Variable.Builder builder) {
    while(reader.hasMoreChildren()) {
      reader.moveDown();
      if(isAttributesNode(reader.getNodeName())) {
        unmarshallAttributes(builder, reader, context);
      } else if("categories".equals(reader.getNodeName())) {
        while(reader.hasMoreChildren()) {
          Category category = readChildItem(reader, context, builder);
          builder.addCategory(category);
        }
      }
      reader.moveUp();
    }
  }

  @Override
  void addAttribute(Object current, Attribute attribute) {
    Variable.Builder builder = (Variable.Builder) current;
    builder.addAttribute(attribute);
  }

  protected void marshallCategories(Variable variable, HierarchicalStreamWriter writer, MarshallingContext context) {
    if(variable.hasCategories()) {
      writer.startNode("categories");
      for(Category c : variable.getCategories()) {
        writeItem(c, context, writer);
      }
      writer.endNode();
    }
  }

}