var ajaxRequete;

function initialiserFormulaire() {

	var objMarque1, objVehicule1, objModele1, objAnnee1;
	var objMarque2, objVehicule2, objModele2, objAnnee2;
	var objMarque3, objVehicule3, objModele3, objAnnee3;
	var objMarque4, objVehicule4, objModele4, objAnnee4;

	try {	// Opera 8.0+, Firefox, Safari
		ajaxRequete = new XMLHttpRequest();
	} catch (e){
		try {	// Internet Explorer
			ajaxRequete = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try {
				ajaxRequete = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e){
				return;
			}
		}
	}

	objMarque1 		= document.getElementById("marque1");
	objAnnee1 		= document.getElementById("annee1");
	objVehicule1 	= document.getElementById("vehicule1");
	objModele1 		= document.getElementById("modele1");
	
	objMarque2 		= document.getElementById("marque2");
	objAnnee2 		= document.getElementById("annee2");
	objVehicule2 	= document.getElementById("vehicule2");
	objModele2 		= document.getElementById("modele2");
	
	objMarque3 		= document.getElementById("marque3");
	objAnnee3 		= document.getElementById("annee3");
	objVehicule3 	= document.getElementById("vehicule3");
	objModele3 		= document.getElementById("modele3");
	
	objMarque4 		= document.getElementById("marque4");
	objAnnee4 		= document.getElementById("annee4");
	objVehicule4 	= document.getElementById("vehicule4");
	objModele4 		= document.getElementById("modele4");
	
	if (objMarque1) {
		
		if (objMarque1.selectedIndex < 1) {
			objAnnee1.options.length = 1;
			objAnnee1.disabled = true;
		}
		
		if (objAnnee1.selectedIndex < 1) {
			objVehicule1.options.length = 1;
			objVehicule1.disabled = true;
		}
		
		if (objVehicule1.selectedIndex < 1) {
			objModele1.options.length = 1;
			objModele1.disabled = true;
		}
		
		objMarque1.onchange 	= function(){afficher_annee(objMarque1, objAnnee1, objVehicule1, objModele1)};
		objAnnee1.onchange 		= function(){afficher_vehicule(objMarque1, objAnnee1, objVehicule1, objModele1)};
		objVehicule1.onchange 	= function(){afficher_modele(objMarque1, objAnnee1, objVehicule1, objModele1)};
	}
	
	if (objMarque2) {
		
		if (objMarque2.selectedIndex < 1) {
			objAnnee2.options.length = 1;
			objAnnee2.disabled = true;
		}
		
		if (objAnnee2.selectedIndex < 1) {
			objVehicule2.options.length = 1;
			objVehicule2.disabled = true;
		}
		
		if (objVehicule2.selectedIndex < 1) {
			objModele2.options.length = 1;
			objModele2.disabled = true;
		}
		
		objMarque2.onchange 	= function(){afficher_annee(objMarque2, objAnnee2, objVehicule2, objModele2)};
		objAnnee2.onchange 		= function(){afficher_vehicule(objMarque2, objAnnee2, objVehicule2, objModele2)};
		objVehicule2.onchange 	= function(){afficher_modele(objMarque2, objAnnee2, objVehicule2, objModele2)};
	}
	
	if (objMarque3) {
		
		if (objMarque3.selectedIndex < 1) {
			objAnnee3.options.length = 1;
			objAnnee3.disabled = true;
		}
		
		if (objAnnee3.selectedIndex < 1) {
			objVehicule3.options.length = 1;
			objVehicule3.disabled = true;
		}
		
		if (objVehicule3.selectedIndex < 1) {
			objModele3.options.length = 1;
			objModele3.disabled = true;
		}
		
		objMarque3.onchange 	= function(){afficher_annee(objMarque3, objAnnee3, objVehicule3, objModele3)};
		objAnnee3.onchange 		= function(){afficher_vehicule(objMarque3, objAnnee3, objVehicule3, objModele3)};
		objVehicule3.onchange 	= function(){afficher_modele(objMarque3, objAnnee3, objVehicule3, objModele3)};
	}
	
	if (objMarque4) {
		
		if (objMarque4.selectedIndex < 1) {
			objAnnee4.options.length = 1;
			objAnnee4.disabled = true;
		}
		
		if (objAnnee4.selectedIndex < 1) {
			objVehicule4.options.length = 1;
			objVehicule4.disabled = true;
		}
		
		if (objVehicule4.selectedIndex < 1) {
			objModele4.options.length = 1;
			objModele4.disabled = true;
		}
		
		objMarque4.onchange 	= function(){afficher_annee(objMarque4, objAnnee4, objVehicule4, objModele4)};
		objAnnee4.onchange 		= function(){afficher_vehicule(objMarque4, objAnnee4, objVehicule4, objModele4)};
		objVehicule4.onchange 	= function(){afficher_modele(objMarque4, objAnnee4, objVehicule4, objModele4)};
	}
	
}

function afficher_annee(objMarque, objAnnee, objVehicule, objModele){

	var index_marque = objMarque.selectedIndex;
	var data;
	
	if (index_marque < 1) {
		objAnnee.options.length = 1;
		objAnnee.disabled = true;
		objVehicule.options.length = 1;
		objVehicule.disabled = true;
		objModele.options.length = 1;
		objModele.disabled = true;
	} else {		

		ajaxRequete.open("POST", "/includes/ajax_annees.php", true);
		ajaxRequete.onreadystatechange = function(){
			if(ajaxRequete.readyState == 4){
				//alert(ajaxRequete.responseText);
				eval(ajaxRequete.responseText);
			}
		}

		ajaxRequete.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); 
		data = 	"marque="+escape(objMarque.options[index_marque].value);
		ajaxRequete.send(data);
	}
}

function afficher_vehicule(objMarque, objAnnee, objVehicule, objModele){

	var index_marque = objMarque.selectedIndex;
	var index_annee = objAnnee.selectedIndex;
	var data;
	
	if (index_annee < 1) {
		objVehicule.options.length = 1;
		objVehicule.disabled = true;
		objModele.options.length = 1;
		objModele.disabled = true;
	} else {		

		ajaxRequete.open("POST", "/includes/ajax_vehicules.php", true);
		ajaxRequete.onreadystatechange = function(){
			if(ajaxRequete.readyState == 4){
				//alert(ajaxRequete.responseText);
				eval(ajaxRequete.responseText);
			}
		}

		ajaxRequete.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); 
		data = "marque="+escape(objMarque.options[index_marque].value)+
			   "&annee="+escape(objAnnee.options[index_annee].value); 
		ajaxRequete.send(data);
	}
}

function afficher_modele(objMarque, objAnnee, objVehicule, objModele){

	var index_marque = objMarque.selectedIndex;
	var index_annee = objAnnee.selectedIndex;
	var index_vehicule = objVehicule.selectedIndex;
	var data;
	
	if (index_vehicule < 1) {
		objModele.options.length = 1;
		objModele.disabled = true;
	} else {		

		ajaxRequete.open("POST", "/includes/ajax_modeles.php", true);
		ajaxRequete.onreadystatechange = function(){
			if(ajaxRequete.readyState == 4){
				//alert(ajaxRequete.responseText);
				eval(ajaxRequete.responseText);
			}
		}

		ajaxRequete.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); 
		data = 	"marque="+escape(objMarque.options[index_marque].value)+
				"&annee="+escape(objAnnee.options[index_annee].value)+
				"&vehicule="+escape(objVehicule.options[index_vehicule].value); 
		ajaxRequete.send(data);
	}
}

if (window.addEventListener) {
  window.addEventListener("load", initialiserFormulaire, false);
} else if (window.attachEvent) {
  window.attachEvent("onload", initialiserFormulaire);
} else {
  window.onload = initialiserFormulaire;
}