/*
    * $Header: /cvsroot/jdbforms/dbforms/src/org/dbforms/config/DbFormsErrors.java,v 1.7 2004/10/20 10:51:26 hkollmann Exp $
    * $Revision: 1.7 $
    * $Date: 2004/10/20 10:51:26 $
    *
    * DbForms - a Rapid Application Development Framework
    * Copyright (C) 2001 Joachim Peer <joepeer@excite.com>
    *
    * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library 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
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   */
  package org.dbforms.config;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.dbforms.util.StringUtil;
  
  import java.util.Hashtable;
  import java.util.Vector;
  
  import javax.servlet.ServletConfig;
  import javax.servlet.ServletContext;
  
  
  
  /***
   * <p>
   * This class gets populated with data from the dbforms-errors.xml file by the
   * ConfigServlet. This class is a kind of "single point of entry" for error
   * messages: it contains the definitions of error message id's, descriptions,
   * severity etc.
   * </p>
   *
   * @author Philip Grunikiewicz
   */
  public class DbFormsErrors {
     private static Log logCat = LogFactory.getLog(DbFormsErrors.class.getName()); // logging category for this class
  
     /*** DOCUMENT ME! */
     public static final String ERRORS = "dbformsErrors";
  
     /*** DOCUMENT ME! */
     public static final char PARAMETER_DELIMITER = '%';
     private Hashtable        errorIDHash; // for quicker lookup by ID
     private ServletConfig    servletConfig;
  
     /***
      * Creates a new DbFormsErrors object.
      */
     public DbFormsErrors() {
        logCat.info("Create instance of DbFormsErrors");
        errorIDHash = new Hashtable();
     }
  
     /***
      * DOCUMENT ME!
      *
      * @param id DOCUMENT ME!
      *
      * @return DOCUMENT ME!
      */
     public Error getErrorById(String id) {
        return (Error) errorIDHash.get(id);
     }
  
  
     /***
      * DOCUMENT ME!
      *
      * @param servletConfig DOCUMENT ME!
      */
     public void setServletConfig(ServletConfig servletConfig) {
        this.servletConfig = servletConfig;
     }
  
  
     /***
      * get access to configuration of config servlet
      *
      * @return DOCUMENT ME!
      */
     public ServletConfig getServletConfig() {
        return servletConfig;
     }
  
  
     /***
      * get access to servlet context in order to interoperate with other
     * components of the web application
     *
     * @return DOCUMENT ME!
     */
    public ServletContext getServletContext() {
       return servletConfig.getServletContext();
    }
 
 
    /***
     * DOCUMENT ME!
     *
     * @param message DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getXMLErrorMessage(String message) {
       String                   langCode   = null;
       String                   language   = null;
       String                   errorCode  = null;
       String                   paramList  = null;
       org.dbforms.config.Error anError    = null;
       String                   xmlMessage = null;
 
       // If message is empty, return immediately
       if ((message == null) || (message.trim().length() == 0)) {
          return null;
       }
 
       // Extract Language , Error Code ID, and parameters
       // ie: English-001:FieldName,200
       // ie: ORA-00001:Oracle Message
       try {
          langCode     = getEmbeddedStringForErrors(message, 0, ':');
          language     = getEmbeddedStringForErrors(langCode, 0, '-');
          errorCode    = getEmbeddedStringForErrors(langCode, 1, '-');
          paramList    = getEmbeddedStringForErrors(message, 1, ':');
       } catch (Exception e) {
          //
          logCat.error("Not in proper format - do not try to convert!");
       }
 
       // Reference to listing of predefined errors (xml file)
       if (errorCode != null) {
          // Error does not contain an id, ignore!				
          if (errorCode.trim().length() == 0) {
             return "";
          }
 
          anError = getErrorById(errorCode);
       }
 
       // Get message associated to language
       if (anError != null) {
          xmlMessage = anError.getMessage(language);
 
          if (xmlMessage != null) {
             // Replace placeholder with supplied parameters
             xmlMessage = insertParametersInString(xmlMessage, paramList);
          } else {
             xmlMessage = "No message defined! - check dbForms-error.xml";
          }
 
          return xmlMessage;
       }
 
       // An error has occured, 
       // however a custom error messages is not available		
       return message;
    }
 
 
    /***
     * DOCUMENT ME!
     *
     * @param error DOCUMENT ME!
     */
    public void addError(Error error) {
       logCat.info("error added: " + error);
       errorIDHash.put(error.getId(), error);
    }
 
 
    /***
     * <p>
     * Method for parsing substring embedded by constant delimeters
     * </p>
     *
     * <p>
     * consider the following string s: English-001:param1, param2
     * </p>
     *
     * <p>
     * <pre>
     *  </pre>
     * </p>
     *
     * @param str DOCUMENT ME!
     * @param afterDelims DOCUMENT ME!
     * @param delim DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    private String getEmbeddedStringForErrors(String str, int afterDelims,
       char delim) {
       int lastIndex = 0;
 
       for (int i = 0; i < afterDelims; i++) {
          lastIndex = str.indexOf(delim, lastIndex) + 1; // search end of cutting
       }
 
       int nextIndex = str.indexOf(delim, lastIndex); // end of cutting
 
       if (nextIndex == -1) {
          nextIndex = str.length();
       }
 
       return str.substring(lastIndex, nextIndex);
    }
 
 
    /***
     * Grunikiewicz.philip  2001-12-04 Replace placeholders by parameters Make
     * sure that parameters required = parameters provided!
     *
     * @param xmlMessage DOCUMENT ME!
     * @param paramList DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    private String insertParametersInString(String xmlMessage, String paramList) {
       // Check if their are parameters expected
       int pos = xmlMessage.indexOf(PARAMETER_DELIMITER);
 
       if ((pos < 0) || (paramList == null)) {
          return xmlMessage; // No parameters found!
       }
 
       // Sort parameter list
       Vector v     = StringUtil.splitString(paramList, ",");
       int    count = 0;
 
       while (pos >= 0) {
          // Replace
          String prefix = xmlMessage.substring(0, pos);
          String suffix = xmlMessage.substring(pos + 1);
          xmlMessage = prefix + (String) v.elementAt(count);
          xmlMessage += suffix;
          pos = xmlMessage.indexOf(PARAMETER_DELIMITER);
          count++;
       }
 
       return xmlMessage;
    }
 }