function ajax()
{
	var obj;
	if (window.XMLHttpRequest){ // Firefox et autres
		obj = new XMLHttpRequest();
	}
	else if (window.ActiveXObject){ // Internet Explorer (Merci IE...)
		var ieversions = [	'Msxml2.XMLHTTP',
							'Microsoft.XMLHTTP',
							'Msxml2.XMLHTTP.5.0',
							'Msxml2.XMLHTTP.4.0',
							'Msxml2.XMLHTTP.3.0'];

		for (var i=0; !obj && i<ieversions.length; i++){
			try {
				obj = new ActiveXObject(ieversions[i]);
			} catch (e){
				obj = null;
			}
		}
	}

	return obj;
}

function $(id){
	return document.getElementById(id);
}

function ajaxLogin(){
	if ($('lgfrm_login') && $('lgfrm_mdp')){
		var xhr = new ajax();
		
		if ($('lgfrm_btn')){
			var btn_original = $('lgfrm_btn').innerHTML;
			
			$('lgfrm_btn').innerHTML = '<img src="images/ajax-loader.gif" alt="" /> Patientez...';
			xhr.open('POST', 'ajax_login.php', true);
			xhr.onreadystatechange = function(){
				if (xhr.readyState == 4){
					if (xhr.responseText == 'OK'){
						document.location.href = document.location.href; 
						$('lgfrm_btn').innerHTML = '<img src="images/ajax-loader.gif" alt="" /> Redirection...';
					} else {
						alert(xhr.responseText);
						$('lgfrm_btn').innerHTML = btn_original;
					}
				}
			}
			xhr.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');
			xhr.send('login='+escape($('lgfrm_login').value)+'&mdp='+escape($('lgfrm_mdp').value));
		}
	}
}

/* Préload de l'image ajax */
var img = new Image();
img.src = 'images/ajax-loader.gif';