package com.elseforif.servlet;

import com.elseforif.servlet.utility.constraint.JVCServletParameterConstraints;
import com.elseforif.servlet.utility.constraint.ServletParameters;
import com.elseforif.servlet.utility.ElseForIfHTMLWriter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import java.io.PrintWriter;

/**
 * This is the base class for the servlets of which elseforif.com is composed.
 * It incorporates a menu mode, which merely governs which menu items are
 * enabled for each page.  This also integrates a custom print writer,
 * which references the aforementioned menu mode via 'getMenuMode()',
 * among other things.
 *
 * @author Jason Van Cleve
 */
abstract public class ElseForIfServlet extends JVCServlet
  {

  public static final int MENU_MODE_NONE = 0;
  public static final int MENU_MODE_HOME = 1;
  public static final int MENU_MODE_PRODUCTS = 2;
  public static final int MENU_MODE_SERVICES = 3;
  public static final int MENU_MODE_DEVELOPMENT = 4;
  public static final int MENU_MODE_CONTACT = 5;

  public static final String P_SENDER = "sender";
  public static final String P_CATEGORY = "category";
  public static final String P_BODY = "body";
  public static final String P_CONFIRMED = "confirmed";
  public static final String ATTRIBUTE_CONTACT_EMAIL_PARAMETERS = "attributeContactEmail";

  protected JVCServletParameterConstraints m_parameterConstraints = null;
  protected int m_menuMode = MENU_MODE_NONE;



  /**
   * Return my "menu mode", an integer indicating how the menu (and the "penu")
   * reflect individual pages.
   *
   * @return my menu mode indicator
   */
  public int getMenuMode()
    {
    return m_menuMode;
    }


  /**
   * Initialize this servlet for use.  Subclasses should remember to call
   * this method when overriding it, even though they may reset some of the
   * values defined here.
   *
   * @param servletConfig an object containing this servlet's configuration
   */
  public void init(ServletConfig servletConfig) throws ServletException
    {
    super.init(servletConfig);
    m_title = "This is Else For If.";
    m_description = "Else For If, an independent, full-service Web site"
          + " construction shop.  We build dynamic, data-driven Web sites"
          + " based on open source software, HTML and XHTML, Java servlets"
          + ", CSS, JavaScript and applets, and we do database design"
          + ", imaging, and more.";
    m_keywords = "else for if, elseforif, web site, web design, web development"
          + ", independent, pacific northwest, construction, solutions, training"
          + ", imaging, open-source, full-service, full service"
          + ", software development, consulting, scalable, interactive"
          + ", data-driven, java, servlets, applets, javascript, html, xhtml"
          + ", xml, linux, apache, lamp, open standards";
    m_truncateClassNamePrefix = "com.elseforif.servlet.";
    }


  /**
   * Create an ElseForIfHTMLWriter and call a form of 'doBoth()' that includes
   * it.  Flush and close the writer upon return.  This method is called by
   * my superclass, JVCServlet.
   *
   * @param request a servlet request
   * @param response a servlet response
   * @param session the user's session
   */
  protected void doBoth(HttpServletRequest request, HttpServletResponse response,
        HttpSession session, PrintWriter printWriter) throws Exception
    {
    ServletParameters in = (m_parameterConstraints != null)
        ? m_parameterConstraints.getParameters(request) : null;
    ElseForIfHTMLWriter out = new ElseForIfHTMLWriter(printWriter, in);
    doBoth(request, response, session, in, out);
    }


  /**
   * This is the default service method for Else For If servlets, adding
   * an explicit ElseForIfHTMLWriter to the signature.  Most subclasses
   * will override this method.
   *
   * @param request a servlet request
   * @param response the response for that request
   * @param session the user's session object
   * @param out a custom HTML output writer
   */
  protected abstract void doBoth(HttpServletRequest request, HttpServletResponse response,
        HttpSession session, ServletParameters in, ElseForIfHTMLWriter out) throws Exception;

  }