package org.andromda.taglibs.breadcrumbs;
   
   import javax.servlet.http.HttpServletRequest;
   import javax.servlet.jsp.JspException;
   import javax.servlet.jsp.PageContext;
   import javax.servlet.jsp.tagext.Tag;
   import javax.servlet.jsp.tagext.TagSupport;
   
   /**
   *
   */
  public class AddTag extends TagSupport
  {
      private static final long serialVersionUID = 34L;
      private String value = null;
  
      /**
       * @return value
       */
      public String getValue()
      {
          return value;
      }
  
      /**
       * @param value
       */
      public void setValue(String value)
      {
          this.value = value;
      }
  
      /**
       * @see javax.servlet.jsp.tagext.TagSupport#doStartTag()
       */
      public int doStartTag() throws JspException
      {
          Object breadCrumbsObject = this.pageContext.getAttribute(BreadCrumbs.SESSION_KEY, PageContext.SESSION_SCOPE);
  
          if (breadCrumbsObject == null)
          {
              BreadCrumbs breadCrumbs = new BreadCrumbs();
              this.pageContext.setAttribute(BreadCrumbs.SESSION_KEY, breadCrumbs, PageContext.SESSION_SCOPE);
              addToBreadCrumbs(breadCrumbs);
          }
          else if (breadCrumbsObject instanceof BreadCrumbs)
          {
              addToBreadCrumbs((BreadCrumbs) breadCrumbsObject);
          }
  
          return Tag.SKIP_BODY;
      }
  
      private void addToBreadCrumbs(BreadCrumbs breadCrumbs)
      {
          HttpServletRequest request = (HttpServletRequest) this.pageContext.getRequest();
  
          BreadCrumb newCrumb = new BreadCrumb(request.getRequestURL().toString(), value);
  
          if (breadCrumbs.isEmpty() == false)
          {
              BreadCrumb lastCrumb = (BreadCrumb) breadCrumbs.getLast();
              if (lastCrumb.hasSimilarProperties(newCrumb))
              {
                  breadCrumbs.set(breadCrumbs.size() - 1, newCrumb);
                  return;
              }
          }
          breadCrumbs.add(newCrumb);
      }
  }