/*
 * Copyright (C) 2005 Alfresco, Inc.
 *
 * Licensed under the Mozilla Public License version 1.1 
 * with a permitted attribution clause. You may obtain a
 * copy of the License at
 *
 *   http://www.alfresco.org/legal/license.txt
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the
 * License.
 */
package org.alfresco.web.bean;

import java.io.PrintWriter;
import java.io.StringWriter;

import javax.servlet.ServletException;

/**
 * Bean used by the error page, holds the last exception to be thrown by the system
 * 
 * @author gavinc
 */
public class ErrorBean
{
   public static final String ERROR_BEAN_NAME = "alfresco.ErrorBean";
   
   private String returnPage;
   private Throwable lastError;

   /**
    * @return Returns the page to go back to after the error has been displayed
    */
   public String getReturnPage()
   {
      return returnPage;
   }

   /**
    * @param returnPage The page to return to after showing the error
    */
   public void setReturnPage(String returnPage)
   {
      this.returnPage = returnPage;
   }

   /**
    * @return Returns the lastError.
    */
   public Throwable getLastError()
   {
      return lastError;
   }

   /**
    * @param lastError The lastError to set.
    */
   public void setLastError(Throwable lastError)
   {
      this.lastError = lastError;
   }
   
   /**
    * @return Returns the last error to occur in string form
    */
   public String getLastErrorMessage()
   {
      String message = "No error currently stored";
      
      if (this.lastError != null)
      {
         StringBuilder builder = null;
         Throwable cause = null;
         if (this.lastError instanceof ServletException && 
             ((ServletException)this.lastError).getRootCause() != null)
         {
            // servlet exception puts the actual error in root cause!!
            Throwable actualError = ((ServletException)this.lastError).getRootCause();
            builder = new StringBuilder(actualError.toString());
            cause = actualError.getCause();
         }
         else
         {
            builder = new StringBuilder(this.lastError.toString());
            cause = this.lastError.getCause(); 
         }
         
         while (cause != null)
         {
            builder.append("<br/><br/>caused by:<br/>");
            builder.append(cause.toString());
            
            if (cause instanceof ServletException && 
             ((ServletException)cause).getRootCause() != null)
            {
               cause = ((ServletException)cause).getRootCause();
            }
            else
            {
               cause = cause.getCause();
            }  
         }
         
         message = builder.toString();
      }
      
      return message;
   }
   
   /**
    * @return Returns the stack trace for the last error
    */
   public String getStackTrace()
   {
      StringWriter stringWriter = new StringWriter();
      PrintWriter writer = new PrintWriter(stringWriter);
      
      if (this.lastError instanceof ServletException && 
          ((ServletException)this.lastError).getRootCause() != null)
      {
         Throwable actualError = ((ServletException)this.lastError).getRootCause();
         actualError.printStackTrace(writer);
      }
      else
      {
         this.lastError.printStackTrace(writer);
      }
      
      return stringWriter.toString().replaceAll("\r\n", "<br/>");
   }
}