var ie = (!window.opera && document.all);
var dom = (!document.all && document.getElementById);
var gallery_index = 0;
var description_index = 0;

function ajaxManager()
        {
        var args = ajaxManager.arguments;
        switch (args[0])
                {
                
                case "load_page":
                        var x = (window.ActiveXObject) ? new ActiveXObject("Microsoft.XMLHTTP") : new XMLHttpRequest();
                        pageWidth = (dom) ? innerWidth : document.body.clientWidth;
                        preload = document.getElementById("preloadLYR");
                        gallery = document.getElementById("galleryLYR");
	   gallery_index = args[1];
                        if (x)
                                {
                                x.onreadystatechange = function()
                                        {
                                        if (x.readyState == 0)
                                                {
                                                preload.innerHTML = "инициализация";
                                                }
                                        else if (x.readyState == 1)
                                                {
                                                preload.innerHTML = "отправка запроса";
                                                }
                                        else if (x.readyState == 2)
                                                {
                                                preload.innerHTML = "request acknowledged";
                                                }
                                        else if (x.readyState == 3)
                                                {
                                                preload.innerHTML = "загрузка...";
                                                setOpacity(0, 'galleryLYR');
                                                }
                                        else if (x.readyState == 4 && x.status == 200)
                                                {
                                                el = document.getElementById(args[2]);
                                                el.innerHTML = x.responseText;
                                                preload.innerHTML = "";
                                                setTimeout("fadeIn('galleryLYR', 0, '99.99')", 1200);
                                                }
                                        }
                                eval("x.open('GET', 'show_photo.php?photo="+galleryArray[gallery_index]+"', true)");
                                x.send(null);
                                }
                        break;

                case "cycle_gallery":
                        if (args[1] == 'forw' && gallery_index != galleryArray.length - 1)
                                {
                                gallery_index++;
                                ajaxManager('load_page', gallery_index, 'galleryLYR');
                                }
                        else if (args[1] == 'rev' && gallery_index != 0)
                                {
                                gallery_index--;
                                ajaxManager('load_page', gallery_index, 'galleryLYR');
                                }
                        break;
                case "hide_access":
                        document.getElementById('accessLYR').style.visibility = "hidden";
                        break;
                case "load_fx":
                        document.getElementById('accessLYR').style.visibility = "hidden";
                        break;
                }
        }


function fadeIn(id, startfade, endfade)
        {
        timer = 0;
        if (startfade < endfade)
                {
                for (i = startfade; i <= endfade; i++)
                        {
                        setTimeout("setOpacity(" + i + ",'" + id + "')", (timer * 20));
                        timer++;
                        }
                }
        }

function setOpacity(opacity, id)
        {
        var el = document.getElementById(id).style;
        el.opacity = (opacity / 100);
        el.MozOpacity = (opacity / 100);
        el.KhtmlOpacity = (opacity / 100);
        el.filter = "alpha(opacity=" + opacity + ")";
        }