FilterPanel.java

/*
 * 
 * This program is free software; you can redistribute it and/or modify it under the 
 * terms of the GNU General Public License, version 2 as published by the Free Software 
 * Foundation.
 *
 * You should have received a copy of the GNU General Public License along with this 
 * program; if not, you can obtain a copy at http://www.gnu.org/licenses/gpl-2.0.html 
 * or from the Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
 * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 *
 * Copyright 2005 - 2008 Pentaho Corporation.  All rights reserved. 
 * 
 * @created Aug 31, 2005 
 * @author James Dixon
 */

package org.pentaho.platform.uifoundation.component.xml;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.dom4j.Document;
import org.dom4j.Element;
import org.pentaho.platform.api.engine.ILogger;
import org.pentaho.platform.api.engine.IPentahoSession;
import org.pentaho.platform.api.util.XmlParseException;
import org.pentaho.platform.engine.core.system.PentahoSystem;
import org.pentaho.platform.engine.services.solution.PentahoEntityResolver;
import org.pentaho.platform.uifoundation.component.FilterDefinition;
import org.pentaho.platform.uifoundation.messages.Messages;
import org.pentaho.platform.util.UUIDUtil;
import org.pentaho.platform.util.xml.XForm;
import org.pentaho.platform.util.xml.dom4j.XmlDom4JHelper;

/**
 * This class stores the defintion of filters that are used by FilterComponent
 * to generate content for user interfaces.
 * 
 * This object supports mulitple filters. It stores information about the
 * sources of the values for each filters. It generates an XForm snippet to
 * represent the selections.
 * 
 * @author James Dixon
 * 
 */
public class FilterPanel {

  public static final boolean debug = PentahoSystem.debug;

  // TODO, move to Java 5, generic as ArrayList<FilterDefinition>
  ArrayList filterList;

  String error;

  String name;

  ILogger logger;

  // TODO sbarkdull, this may be worth reimplementing, and not using a DOM Document
  // but using SAX to parse the document. Note that the document is parsed in this
  // constructor, and then thrown away. This is usually a good sign that SAX
  // is a more optimal solution. On the other hand, these documents are small, and there
  // are few of them, so maybe it is no big deal.
  public FilterPanel(final IPentahoSession session, final Document document, final ILogger logger)
      throws FilterPanelException {
    this.logger = logger;
    filterList = new ArrayList();
    if (document != null) {
      // create the filter definitions
      List filterNodes = document.selectNodes("filters/filter"); //$NON-NLS-1$
      Iterator filtersIterator = filterNodes.iterator();
      while (filtersIterator.hasNext()) {
        Element filterNode = (Element) filtersIterator.next();
        FilterDefinition filterDefinition = FilterDefinitionFactory.create(filterNode, session, logger);
        filterList.add(filterDefinition);
      }
      if (filterList.size() == 0) {
        error = Messages.getInstance().getString("FilterPanel.ERROR_0001_NO_FILTERS"); //$NON-NLS-1$
        return;
      }
    }
  }

  public List getFilters() {
    return filterList;
  }

  public boolean populate(final Map parameterProviders, final Map defaultValues) {
    int ok = 0;
    int fail = 0;
    if (filterList != null) {
      Iterator filtersIterator = filterList.iterator();
      while (filtersIterator.hasNext()) {
        FilterDefinition filterDefinition = (FilterDefinition) filtersIterator.next();
        if (filterDefinition.populate(parameterProviders, (String[]) defaultValues.get(filterDefinition.getName()))) {
          ok++;
        } else {
          fail++;
        }
      }
    }
    return (fail == 0);
  }

  public Document getXForm(final String actionUrl) {

    StringBuffer content = new StringBuffer();
    Document document = null;

    // String strUuid = UUID.randomUUID().toString().replaceAll( "-", "_");
    String strUuid = UUIDUtil.getUUIDAsString().replaceAll("-", "_"); //$NON-NLS-1$ //$NON-NLS-2$

    content.append("<filters xmlns:xf=\"http://www.w3.org/2002/xforms\"><id>" + strUuid + "</id><title><![CDATA[" + //$NON-NLS-1$ //$NON-NLS-2$
        Messages.getInstance().getEncodedString(name) + "]]></title><description></description><help></help>" + //$NON-NLS-1$
        "<action><![CDATA[" + actionUrl + "]]></action>"); //$NON-NLS-1$ //$NON-NLS-2$

    if (error != null) {
      content.append("<error>"); //$NON-NLS-1$
      content.append(error);
      content.append("</error>"); //$NON-NLS-1$
    } else if (filterList == null) {
      content.append("<error>"); //$NON-NLS-1$
      content.append(Messages.getInstance().getString("FilterPanel.ERROR_0003_NO_FILTER_VALUES")); //$NON-NLS-1$
      content.append("</error>"); //$NON-NLS-1$
    } else {
      try {
        Iterator filtersIterator = filterList.iterator();
        StringBuffer xformHeader = new StringBuffer();
        String formName = null;
        while (filtersIterator.hasNext()) {
          FilterDefinition filterDefinition = (FilterDefinition) filtersIterator.next();
          String filterName = filterDefinition.getName();
          if (formName == null) {
            formName = filterName;
          }
          String title = filterDefinition.getTitle();
          StringBuffer xformBody = new StringBuffer();
          //                    XForm.createXFormHeader(name, xformHeader);
          filterDefinition.getXForm(xformHeader, xformBody);
          //                    XForm.completeXForm(XForm.OUTPUT_HTML, filterName, new StringBuffer(), xformBody);
          // content.append( "<filter name=\""+filterName+"\">"
          // ).append(filterContent).append( "</filter>" );
          // //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$

          content.append("<filter><name><![CDATA[" + filterName + "]]></name>") //$NON-NLS-1$ //$NON-NLS-2$
              .append("<title><![CDATA[" + title + "]]></title><control>") //$NON-NLS-1$ //$NON-NLS-2$
              .append(xformBody).append("</control></filter>"); //$NON-NLS-1$
        }
        XForm.completeXFormHeader(formName, xformHeader);
        content.append(xformHeader);
      } catch (Exception e) {
        logger.error(Messages.getInstance().getErrorString("FilterPanel.ERROR_0004_COULD_NOT_CREATE_CONTENT"), e); //$NON-NLS-1$
      }

    }
    content.append("</filters>"); //$NON-NLS-1$
    if (FilterPanel.debug) {
      logger.debug(content.toString());
    }
    try {
      document = XmlDom4JHelper.getDocFromString(content.toString(), new PentahoEntityResolver());
    } catch(XmlParseException e) {
      logger.error(Messages.getInstance().getErrorString("FilterPanel.ERROR_0004_COULD_NOT_CREATE_CONTENT"), e); //$NON-NLS-1$
    }
    return document;
  }

}