var refActuel = 0, position = -30, opaque = 0, liensTab = [], taille, liensIndice = -1, liensTimer, isIE = !!document.all;
function move(elem){
    if (!liensTimer && elem == liensIndice) {
        return false;
    }
    if (liensTimer) {
        clearInterval(liensTimer);
        liensTimer = null;
    }
    var dir = liensTab[elem] > position ? 1 : -1;
    var menu_ref = _$('menu_item');
    if (liensIndice >= 0) {
        menu_ref.getElementsByTagName('li')[liensIndice].className = '';
    }
    function actionTimer(){
        if (Math.abs(liensTab[elem] - position) > 4) {
            position += 5 * dir;
            menu_ref.style.backgroundPosition = '10px ' + position + 'px';
        }
        else {
            clearInterval(liensTimer);
            position = liensTab[elem];
            menu_ref.style.backgroundPosition = '10px ' + position + 'px';
            liensIndice = elem;
            menu_ref.getElementsByTagName('li')[liensIndice].className = 'active';
            liensTimer = null;
        }
    }
    liensTimer = setInterval(actionTimer, 10);
}

function inc(){
    if (isIE) {
        _$('chg_flux').filters[0].opacity = opaque;
        _$('ajout').filters[0].opacity = (opaque * 2);
    }
    else {
        _$('chg_flux').style.opacity = opaque / 100;
        _$('ajout').style.opacity = opaque / 50;
    }
    opaque += 5;
    if (opaque > 50) {
        opaque = 50;
        getFlux();
    }
    else {
        setTimeout(inc, 50);
    }
}

function dec(){
    if (isIE) {
        _$('chg_flux').filters[0].opacity = opaque;
        _$('ajout').filters[0].opacity = (opaque * 2);
    }
    else {
        _$('chg_flux').style.opacity = opaque / 100;
        _$('ajout').style.opacity = opaque / 50;
    }
    opaque -= 5;
    if (opaque < 0) {
        opaque = 0;
        _$('chg_flux').style.display = 'none';
        _$('ajout').style.display = 'none';
    }
    else {
        setTimeout(dec, 50);
    }
}

function navRSS(reference){
    if (refActuel == reference) {
        return false;
    }
    _$('navTab').getElementsByTagName('div')[reference].style.backgroundPosition = 'bottom';
    _$('navTab').getElementsByTagName('div')[refActuel].style.backgroundPosition = 'top';
    refActuel = reference;
    taille = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;
    _$('chg_flux').style.height = Math.max(taille, document.body.offsetHeight) + 'px';
    opaque = 0;
    _$('chg_flux').style.display = 'block';
    _$('ajout').style.display = 'block';
    if (isIE) {
        _$('chg_flux').style.filter = 'alpha(opacity=0)';
        _$('ajout').style.filter = 'alpha(opacity=0)';
    }
    inc();
    return;
}

function getFlux(){
    var nombre = refActuel ? 10 : 2;
    var xhr = getXHR();
    xhr.onreadystatechange = function(){
        if (xhr.readyState == 4 && xhr.status == 200) {
            _$('corps').innerHTML = xhr.responseText;
            taille = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;
            if (taille < _$('corps').offsetHeight + 125) {
                _$('footer').style.position = 'static';
            }
            else {
                _$('footer').style.position = 'absolute';
                _$('footer').style.bottom = '10px';
            }
            dec();
        }
    };
    xhr.open("POST", '/cicerone/actu_ajx.php', true);
    xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;charset=iso-8859-1");
    xhr.send('flux=' + refActuel + '&nb=' + nombre);
}

function getXHR(){
    var xhr = null;
    if (window.XMLHttpRequest) {
        try {
            xhr = new XMLHttpRequest();
        } 
        catch (e) {
        }
    }
    else 
        if (window.ActiveXObject) {
            try {
                xhr = new ActiveXObject("Msxml2.XMLHTTP");
            } 
            catch (e1) {
                try {
                    xhr = new ActiveXObject("Microsoft.XMLHTTP");
                } 
                catch (e2) {
                }
            }
        }
    return xhr;
}

function _$(un_id){
    return document.getElementById(un_id);
}

var init = function(){
    _$('actif').onclick = function(){
        return false;
    };
    var liens = _$('menu').getElementsByTagName('li');
    var i = liens.length;
    while (i) {
        i--;
        liensTab[i] = isIE && !navigator.appVersion.match('MSIE 8') ? liens[i].offsetTop : liens[i].offsetTop - _$('menu').offsetTop;
        liens[i].ref = i;
        liens[i].onmouseover = function(){
            move(this.ref);
        };
        liens[i].onmouseout = function(){
            move(_$('actif').ref);
        };
    }
    move(_$('actif').ref);
    if (isIE) {
        _$('chg_flux').style.filter = 'alpha(opacity=0)';
        _$('ajout').style.filter = 'alpha(opacity=0)';
    }
    else {
        _$('chg_flux').style.opacity = 0;
        _$('ajout').style.opacity = 0;
    }
    var listeItem = _$('navTab').getElementsByTagName('div');
    i = listeItem.length;
    while (i) {
        i--;
        listeItem[i].ref = i;
        listeItem[i].onclick = function(){
            navRSS(this.ref);
        };
    }
    liens = null;
    listeItem = null;
}();