/*
 * Copyright (C) 2003-2007 eXo Platform SAS.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or (at your option) any later version.
 *
 * 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.
 *
 * 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.exoplatform.services.workflow.impl.jbpm;

import java.io.InputStream;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
import org.exoplatform.services.log.ExoLogger;
import org.exoplatform.services.log.Log;
import org.exoplatform.services.workflow.Form;
import org.exoplatform.services.workflow.WorkflowFormsService;
import org.exoplatform.services.workflow.WorkflowServiceContainer;
import org.jbpm.JbpmContext;
import org.jbpm.file.def.FileDefinition;
import org.jbpm.graph.def.ProcessDefinition;

/**
 * Created y the eXo platform team User: Benjamin Mestrallet Date: 17 mai 2004
 */
public class WorkflowFormsServiceImpl implements WorkflowFormsService {

  /**
   * double nested map : definitionId's --> stateName's --> Form's
   */
  private static Map                   allForms = new HashMap();

  private WorkflowServiceContainerImpl container;

  private static final Log LOG = ExoLogger.getLogger(WorkflowFormsServiceImpl.class);

  public WorkflowFormsServiceImpl(WorkflowServiceContainer workflowServiceContainer) {
    this.container = (WorkflowServiceContainerImpl) workflowServiceContainer;
  }

  public Form getForm(String definitionStringId, String stateName, Locale locale) {
    long definitionId = Long.parseLong(definitionStringId);
    Form formConfiguration = null;
    if (stateName == null)
      throw new NullPointerException("stateName is null in Form.getForm");
    Map stateNameToForms = (Map) allForms.get(new Long(definitionId));
    if (stateNameToForms == null) {
      addForms(definitionId, locale);
      stateNameToForms = (Map) allForms.get(new Long(definitionId));
    }

    formConfiguration = (Form) stateNameToForms.get(stateName);
    if (stateNameToForms == null)
      throw new IllegalArgumentException("no form was specified for state '" + stateName
          + "' in definition '" + definitionId + "'");

    return formConfiguration;
  }

  private void addForms(long definitionId, Locale locale) {
    if (!allForms.containsKey(new Long(definitionId))) {
      Map stateNameToForms = new HashMap();
      //JbpmSession session = null;
      try {
        // session = container.openSession();
        JbpmContext jbpmContext = container.openJbpmContext();
        ProcessDefinition pD = jbpmContext.getGraphSession().loadProcessDefinition(definitionId);
        FileDefinition fD = pD.getFileDefinition();
        InputStream iS = fD.getInputStream("forms.xml");
        SAXReader reader = new SAXReader();
        Document document = reader.read(iS);
        Element rootElement = document.getRootElement();
        List list = rootElement.elements("form");
        for (Iterator iter = list.iterator(); iter.hasNext();) {
          Element element = (Element) iter.next();
          Form formConfiguration = new FormImpl(fD, element, locale);

          stateNameToForms.put(formConfiguration.getStateName(), formConfiguration);
        }
        allForms.put(new Long(definitionId), stateNameToForms);
      } catch (DocumentException e) {
        LOG.warn(e.getMessage(), e);
      }
    }
  }

  public void removeForms(String processDefinitionId) {
    allForms.remove(new Long(processDefinitionId));
  }
}
