//Variable


var nb_elements= new Array();
nb_elements[1]=3;
nb_elements[2]=3;

var oldscrollposition=0;
var scrolling=true;
var diff=0;
var actpos=0;
var corrpos=0;
var addedpos=0;
var scroll_statut = true;



var repere_scroll = new Array();

// Methode init_repere_scroll : initialise le tableau repere_scroll

function init_repere_scroll(){
  for (var a=1; a<=(nb_elements.length-1); a++){
    repere_scroll[a] = 1;
  }
}


// Methode move : deplace le menu (effet de scrolling) appel recusif

function move() {
   if ((diff>0.5)||(diff<-0.5)){	
  	
    obj_data.style.left=oldscrollposition+(diff/4);		
    oldscrollposition += diff/4;		
    diff -= diff/4;		
    aktiv = window.setTimeout("move()",20);
  }else{			  
    window.clearTimeout(aktiv);		
    var temp=parseInt(obj_data.style.left);		
    corrpos = actpos + addedpos;
    obj_data.style.left = corrpos;
    scrolling=true;
    scroll_statut=true;
  }
}


// Methode visBouton : qui modifie la visibilité des deux boutons

function visBouton (n){
  var totalcount = nb_elements[n]; // 2
  var presobj = document.getElementById("pres"+n);
  var suivobj = document.getElementById("suiv"+n);
  
  
  if (nb_elements[n]==1)
  {
	    presobj.style.visibility = "hidden";
	    suivobj.style.visibility = "hidden";
	   
  }
  else
  {
	  	if(repere_scroll[n] == 1)
	  	{	
	    	presobj.style.visibility = "hidden";
	    	suivobj.style.visibility = "visible";
	  	}
	  	else 
	  		if(repere_scroll[n] == totalcount)
	  		{
			    presobj.style.visibility = "visible";
			    suivobj.style.visibility = "hidden";
			}
			else
			{
	  			presobj.style.visibility="visible";
	    		suivobj.style.visibility="visible";	
	   		} 
  }
}


// Methode moveLeft : qui permet deplacer le menu vers la gauche

function MoveLeft(num,cwidth){
  if(scroll_statut){
    scroll_statut = false;
    obj_data = document.getElementById("data_scroll_"+num);
    oldscrollposition=parseInt(obj_data.style.left);
    repere_scroll[num] = repere_scroll[num]-1;
    visBouton(num);
    if((parseInt(obj_data.style.left))<0){
      moveScroll(cwidth);
    }
  }  
}

// Methode moveRight : qui permet deplacer le menu vers la droite 

function MoveRight(num,cwidth){
  if(scroll_statut){
  // On desactive la fonctionalité 
    scroll_statut = false;
   
    obj_data = document.getElementById("data_scroll_"+num);
    repere_scroll[num] = repere_scroll[num]+1;
    oldscrollposition=parseInt(obj_data.style.left);
    visBouton(num);
    if((parseInt(obj_data.style.left))>-((cwidth*nb_elements[num])-cwidth)){
     
      moveScroll(-cwidth);
    }
  } 
}

// Methode moveScroll : qui permet deplacer le menu  
 
function moveScroll(newposition){
  if(scrolling){
    diff=newposition;
	addedpos=newposition;
    scrolling=false;
	actpos = parseInt(obj_data.style.left);	
    move();
  }
}
init_repere_scroll();