window.onload = init;

var idimgprincipal = "imgbig";

var descarg = '';
var impresion;
var ident;
var imagenes_array = new Array();
var imagenActual;


//CREA UN OBJETO JAVASCRIPT DE TIPO IMAGEN
function Imagen(id,baja,alta,imp,id_gal, pos){ 
   this.id = id;      this.baja = baja;      this.alta = alta;     
   this.imp = imp;      this.id_gal = id_gal;      this.pos = pos;      
}

function init(){
   
   var fotoinicial = getURLParam("fini");
   if(!isEmpty(fotoinicial) || fotoinicial=="" || fotoinicial==null ){
      fotoinicial = 1;
   }
   cargarImgsArray();
   recargarFotos(fotoinicial);

}

function recargarFotos(posicion){
   cargarFotoPrincipal(posicion);
   recargarThumbNails(posicion);
}

function cargarFotoPrincipal(posicion){

   ponerCargando();
  
   imagenActual = posicion;
  
   var imgreturn = document.createElement("img");
   
   imgreturn.border = "0";
   imgreturn.id = idimgprincipal;
   imgreturn.src = imagenes_array[posicion].alta;

   imgreturn.onload = function (){
		document.getElementById(idimgprincipal).parentNode.replaceChild(imgreturn,document.getElementById(idimgprincipal));
   }

   
}

function ponerCargando(){
	var elemimg = document.createElement("img");
	elemimg.id = idimgprincipal;
	elemimg.src = "/images/ajax-loader.gif";
	document.getElementById(idimgprincipal).parentNode.replaceChild(elemimg,document.getElementById(idimgprincipal));
}

function recargarThumbNails(posicion){
   var franja = document.getElementById("filadefotos_des");
   franja.innerHTML = "";

   

   var imgselec = crearThumbNail(posicion);

   franja.appendChild(imgselec);
   
   var imgcrear = imgselec; 
   var imgtmp;
   var num_mostrar = 4;
   var tmp_posicion = posicion;
    
   if(imagenes_array.length<=3) num_mostrar=imagenes_array.length-1;
    
      var realubic = (tmp_posicion*1)+1;
   for(i=(tmp_posicion*1)+1, control=0; control<num_mostrar; i++, control++){
         if(realubic>(imagenes_array.length-1))realubic=0;
         if(imagenes_array[realubic]!=null){
            imgtmp = crearThumbNail(realubic);
            franja.insertBefore(imgtmp,imgcrear.nextSibling);               imgcrear = imgtmp;
         }
         realubic++;
   }
   
   imgcrear = imgselec;
   
   var nums_mostrar = imagenes_array.length-(num_mostrar+1);
   if(nums_mostrar>4)nums_mostrar=4;
   var tmps_posicion = posicion;
   
   var realpos = tmps_posicion-1; 
      
   for(i=tmps_posicion-1, control=0; control<nums_mostrar; i--, control++){
      if(realpos<0)realpos = imagenes_array.length-1;
      if(imagenes_array[realpos]!=null){   
         imgtmp = crearThumbNail(realpos);
         franja.insertBefore(imgtmp,imgcrear);
         imgcrear = imgtmp;
      }
      realpos--;
   }
   
   var divcliar = document.createElement("div");
   divcliar.className = "clear";
   
   franja.appendChild(divcliar);
}

function crearThumbNail(postmp){

   var divtmp = document.createElement("div");
   divtmp.className="modimgsgalerias_des";

   var atmp = document.createElement("a");
   atmp.href = "javascript:recargarFotos("+postmp+")";
   
   var imgreturn = document.createElement("img");
   
   imgreturn.height = "75";
   imgreturn.width = "100";
   //imgreturn.height = "62";
   //imgreturn.width = "90";
   imgreturn.border = "0";
   imgreturn.src = imagenes_array[postmp].baja;
   
   atmp.appendChild(imgreturn);
   divtmp.appendChild(atmp);
      
   return divtmp;
}


function getURLParam(strParamName){
	var strReturn = null;
	var strHref = window.location.href;
	if ( strHref.indexOf("?") > -1 ){
		var strQueryString = strHref.substr(strHref.indexOf("?")).toLowerCase();
		var aQueryString = strQueryString.split("&");
		for ( var iParam = 0; iParam < aQueryString.length; iParam++ ){
			if (
					aQueryString[iParam].indexOf(strParamName.toLowerCase() + "=") > -1 ){
				var aParam = aQueryString[iParam].split("=");
				strReturn = aParam[1];
				break;
			}
		}
	}
	return unescape(strReturn);
}