function Logout()
{
   var http = GetXmlHttpObject()
   if (!http)
      return

   http.onreadystatechange = function()
   {
      if (http.readyState == 4 && http.status == 200)
      {
         window.location = "/"
      }
   }
   var url = "/Login.php?Logout";
   SendGetRequest(http, url);
}

function DisplayLoggedInMessage()
{
   var LoginResult = ById("iLoginResult")
   LoginResult.innerHTML = "You are logged in as an Administrator. "
      + '<a href="javascript:Logout()">Logout</a>'
   LoginResult.style.color = "#080"
}

function ClearLoginFields()
{
   ById("iLoginInput").value = ""
   ById("iPasswordInput").value = ""
}

function CLoginQuery()
{
   var http = GetXmlHttpObject()
   if (!http)
      return

   http.onreadystatechange = function()
   {
      if (http.readyState == 4 && http.status == 200)
      {
         ProcessResponse(http.responseText)
      }
   }

   function ProcessResponse(text)
   {
      if (Trim(text) == "true")
      {
         g_IsLoggedIn = true
         DisplayLoggedInMessage()
         LoadAllTextItems()
         ClearLoginFields()
      }
      else if (Trim(text) == "false")
      {
         var ResultDiv = ById("iLoginResult")
         ResultDiv.innerHTML = "Your login attempt failed."
         ResultDiv.style.color = "#800";
         ClearLoginFields()
      }
   }

   var Login = ById("iLoginInput").value
   var Password = ById("iPasswordInput").value

   if (Trim(Login) == "" || Trim(Password) == "")
      return

   var url = "/Login.php";
   var params = "Login=" + Login + "&Password=" + Password;
   SendPostRequest(http, url, params);
}

function Login()
{
   new CLoginQuery()
}