/*
    showhide(sectionID, showButtonID, hideButtonID)
        toggle style.display for the section, and which button is showing



*/

function showhide(sectionID, showButtonID, hideButtonID){
    /*
        toggle style.display for the section, and which button is showing
        if section.style.display = none (section is hidden)
            set section.style.display to '' (show it)
            set showButton.style.display to 'none'
            set hideButton.style.display to '' (show it)
        else (section is showing)
            set section.style.display to 'none'
            set showButton.style.display to '' (show it)
            set hideButton.style.display to 'none'
    */
    var o_section = eval(sectionID);
    var o_showButton = eval(showButtonID);
    var o_hideButton = eval(hideButtonID);
    
    if (o_section.style.display == 'none'){
        o_section.style.display = '';
        o_showButton.style.display = 'none';
        o_hideButton.style.display = '';
    }
    else{
        o_section.style.display = 'none';
        o_showButton.style.display = '';
        o_hideButton.style.display = 'none';
    }
}

function popup_page(url) {
    window.open(url,"","height=450,width=600,directories=no,location=no,menubar=no", true);
}