//animate the opening of the branch (span.grower jQueryElement)
function openBranch(jQueryElement, noAnimation) {
    jQueryElement.addClass('OPEN').removeClass('CLOSE');
    if(noAnimation)
        jQueryElement.parent().find('ul:first').show();
    else
        jQueryElement.parent().find('ul:first').slideDown();
}
//animate the closing of the branch (span.grower jQueryElement)
function closeBranch(jQueryElement, noAnimation) {
    jQueryElement.addClass('CLOSE').removeClass('OPEN');
    if(noAnimation)
        jQueryElement.parent().find('ul:first').hide();
    else
        jQueryElement.parent().find('ul:first').slideUp();
}

//animate the closing or opening of the branch (ul jQueryElement)
function toggleBranch(jQueryElement, noAnimation) {
    if(jQueryElement.hasClass('OPEN'))
        closeBranch(jQueryElement, noAnimation);
    else
        openBranch(jQueryElement, noAnimation);
}

//when the page is loaded...
$(document).ready(function () {
    //to do not execute this script as much as it's called...
    if(!$('ul.tree.dhtml').hasClass('dynamized'))
    {
        //add growers to each ul.tree elements
        $('ul.tree.dhtml ul').prev().each (function () {
            $(this).replaceWith ('<span class="grower OPEN ' + $(this).attr('class') + '">' + $(this).html() + '</span>')
        });

        //dynamically add the '.last' class on each last item of a branch
        $('ul.tree.dhtml ul li:last-child, ul.tree.dhtml li:last-child').addClass('last');

        //collapse every expanded branch
        $('ul.tree.dhtml span.grower.OPEN').addClass('CLOSE').removeClass('OPEN').parent().find('ul:first').hide();
        $('ul.tree.dhtml').show();

        //open the tree for the selected branch
        $('ul.tree.dhtml .selected').parents().each( function() {
            if ($(this).is('ul'))
                toggleBranch($(this).prev(), true);
        });
        toggleBranch( $('ul.tree.dhtml .selected').prev(), true);

        //add a fonction on clicks on growers
        $('ul.tree.dhtml span.grower').click(function(){
            state = $(this).hasClass('OPEN');
            // close all branchs
            $('ul.tree li span').each(function(){closeBranch($(this));});
            // toggle clicked branch
            if (!state)
                openBranch($(this));
        });
        //mark this 'ul.tree' elements as already 'dynamized'
        $('ul.tree.dhtml').addClass('dynamized');

        $('ul.tree.dhtml').removeClass('dhtml');
    }
});