/*
    * Copyright 2007 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 1.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl1.php
    *
   * 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.kuali.student.common.ui.client.security;
  
  import org.kuali.student.common.ui.client.application.Application;
  import org.kuali.student.common.ui.client.application.ApplicationContext;
  import org.kuali.student.common.ui.client.widgets.KSErrorDialog;
  import org.kuali.student.common.ui.client.widgets.KSLightBox;
  
  import com.google.gwt.event.dom.client.ClickEvent;
  import com.google.gwt.event.dom.client.ClickHandler;
  import com.google.gwt.http.client.Request;
  import com.google.gwt.http.client.RequestBuilder;
  import com.google.gwt.http.client.RequestCallback;
  import com.google.gwt.http.client.RequestException;
  import com.google.gwt.http.client.Response;
  import com.google.gwt.http.client.URL;
  import com.google.gwt.user.client.ui.Button;
  import com.google.gwt.user.client.ui.FlexTable;
  import com.google.gwt.user.client.ui.Label;
  import com.google.gwt.user.client.ui.PasswordTextBox;
  import com.google.gwt.user.client.ui.TextBox;
  import com.google.gwt.user.client.ui.VerticalPanel;
  
  /**
   * This implements the SessionTimeoutHandler. The timeout is handled by displaying a spring
   * security login panel.  
   * 
   * @author Kuali Student Team
   *
   */
  public class SpringSecurityLoginDialogHandler implements SessionTimeoutHandler{
  	final static ApplicationContext context = Application.getApplicationContext();
  	static  boolean CASrequiresAPageRefreshViaJavascript = Boolean.TRUE;
  	public final String TIMEOUT_MSG = "Your session has timed out. Please login again.";
  	
  	protected KSLightBox lightbox;
      protected TextBox username;
      protected PasswordTextBox password;
      protected Label errorLabel;
      
    private native void reload() /*-{
      $wnd.location.reload();
     }-*/;
  
  	@Override
  	public boolean isSessionTimeout(Throwable error) {
          boolean InvocationException = error.toString().contains("com.google.gwt.user.client.rpc.InvocationException");
          boolean CAS = error.toString().contains(""); // The return login page will from cas because spring filter it
          boolean normalLogin =    error.toString().contains("Login"); // the return login will from normal spring Authentication
  
          //until I havent had a chance to see what the CAS loging looks like I am making it default that the javascript do
          // a page refresh rather than showing a login dialogbox. Thus we will be taken to login.jsp screen correlating with
          // the chosen filter {cas or normal spring form}
  
          if(CAS )
          {
              CASrequiresAPageRefreshViaJavascript = true;
          }
  
      	return CAS || normalLogin ;
      }
      
      @Override
  	public void handleSessionTimeout() {
          if(!CASrequiresAPageRefreshViaJavascript){
      	if (lightbox == null){
      		createLoginPanel();
      	} else {
      		resetLoginPanel();
      	}
      	lightbox.setSize(460, 220);
          lightbox.show();
          }else{reload();}
  	}
  
  	private void createLoginPanel(){
  		lightbox = new KSLightBox();
          VerticalPanel panel = new VerticalPanel();
  
          FlexTable table = new FlexTable();
  
          errorLabel = new Label();
          errorLabel.setText(TIMEOUT_MSG);
          errorLabel.setStyleName("KSError");
          
         username = new TextBox();
         username.setName("j_username");
 
         password = new PasswordTextBox();
         password.setName("j_password");
         
         table.setText(0, 0, "Username");
         table.setWidget(0, 1, username);
 
         table.setText(1,0, "Password");
         table.setWidget(1,1, password);
                              
         table.setWidget(2,0,(new Button("Login", new ClickHandler() {   
             public void onClick(ClickEvent event) {
                 
                 StringBuffer postData = new StringBuffer();
                 postData.append(URL.encode("j_username")).append("=").append(username.getText());
                 postData.append("&").append(URL.encode("j_password")).append("=").append(password.getText());
                 
                 RequestBuilder builder = new RequestBuilder(RequestBuilder.POST, context.getApplicationContextUrl() + "/j_spring_security_check");
                 builder.setHeader("Content-type", "application/x-www-form-urlencoded");
 
                 try{
                     builder.sendRequest(postData.toString(), new RequestCallback(){
 
                         @Override
                         public void onError(Request req, Throwable caught) {
                         	lightbox.hide();
                         	KSErrorDialog.show(caught);
                         }
 
                         @Override
                         public void onResponseReceived(Request req, Response res) {
                             if (res.getStatusCode() == Response.SC_OK && !res.getText().contains("Bad credentials")){
                             	lightbox.hide();
                             } else {
                                 errorLabel.setText("Your login attempt was not successful, try again.");
                             }
                         }});
                 } catch (RequestException e) {
                 	KSErrorDialog.show(e);
                 }                
             }
         }
         )));
                 
         panel.add(errorLabel);
         panel.add(table);
  
         panel.setStyleName("KSLoginPanel");
         lightbox.setWidget(panel);
     }
 	
 	private void resetLoginPanel(){
 		username.setText("");
 		password.setText("");
 		errorLabel.setText(TIMEOUT_MSG);		
 	}
     
 }