function login(){

var usernameField = new Ext.form.TextField({
                fieldLabel: 'User Name',
                labelWidth:50,
                name: 'username',
                allowBlank:false
        });

var passwordField = new Ext.form.TextField({
                fieldLabel: 'Password',
                labelWidth:50,
                inputType:'password',
                name: 'password',
                allowBlank:false
        });

var loginForm = new Ext.form.FormPanel({
                id:'objFormField',
                layout:'form',
                height:80,
                frame:true,
                        items: [
                        {
                                layout:'form',
                                items:[
                                        usernameField.show(),
                                        passwordField.show()
                                ]
                        }]
});


var cp = new Ext.state.CookieProvider({
       path: "/deepsky",
       domain: "nersc.gov"
});


var loginWin = new Ext.Window({
        id: 'login',
        title: 'NERSC LDAP Login',
        width: 450,
        autoHeight:true,
        minWidth: 450,
        layout: 'form',
        plain:true,
        bodyStyle:'padding:5px;',
        buttonAlign:'center',
        items: [loginForm
                ],
                buttons: [{
                        text: 'Cancel',
                        handler:function(){
                                loginWin.close();
                        }
                },{
                        text: 'Login',
                        handler:function(){
                            loginForm.form.submit({
                              method:'POST',
                              waitTitle:'Please wait',
                              waitMsg:'Authenticating...',
                              url:'../ldapvalidation_json.php',
                              timeout:300000,
                              success:function(f,a){
                                  if (a.response.responseText == "0"){
                                      Ext.Msg.alert('Response','No Search Results Found');
                                  }else{
                                      var respData = Ext.util.JSON.decode(a.response.responseText);
                                      //Ext.Msg.alert('Success',respData.uservalidation[0].valid);
                                      if (respData.uservalidation[0].valid == '1'){
                                        cp.set('deepskyuser',{'validated':'1'});
                                        loginWin.close();
                                        //spotlight.destroy();
                                      }else{
                                           Ext.Msg.alert('Invalid Login',respData.uservalidation[0].message);
                                      }

                                  }
                              },
                              failure:function(form, action){
                                        if(action.failureType == 'server'){
                                                obj = Ext.util.JSON.decode(action.response.responseText);
                                                Ext.Msg.alert('Oops!', obj.errors.reason);
                                        }else{
                                                Ext.Msg.alert('Message', 'Please make sure the indicated fields have valid data.');
                                        }
                                         Ext.Msg.alert('Message','There are difficulties displaying the results. '+action.response.responseText);


                                },
                            });
                        }
                }]
});

// Check session cookie to see if currently logged in
Ext.state.Manager.setProvider(cp);
var objVal = cp.get("deepskyuser");
   if (!objVal){
       cp.set('deepskyuser',{'validated':'0'});
        loginWin.show();
        //spotlight.show(Ext.get("login"));
   }else{
        if (objVal.validated == '0'){
                // show login window if not logged in
                loginWin.show();
                //spotlight.show(Ext.get("login"));
        }
   }



}