// JScript File

function toggleBox(szDivID, iState) // 1 visible, 0 hidden
{
   var obj = document.layers ? document.layers[szDivID] :
   document.getElementById ? document.getElementById(szDivID).style :
   document.all[szDivID].style;
   obj.visibility = document.layers ? (iState ? "show" : "hide") :
   (iState ? "visible" : "hidden");
}

function checkZoekTerm(form) {
    var zoekTerm = trimAll(form.ZoekTerm.value);
    form.ZoekTerm.value = zoekTerm;
    if(zoekTerm == '') {
        alert('U heeft geen zoekterm gespecificeerd.');
        form.ZoekTerm.focus();
        return false;
    }
    
    if(!checkSelection(form.products)) {
        return false;
    }
}

function checkAdvanced(form) {
    var advancedAnd = trimAll(form.AdvancedAnd.value);
    var advancedOr = trimAll(form.AdvancedOr.value);
    var advancedPhrase = trimAll(form.AdvancedPhrase.value);
    var advancedWithout = trimAll(form.AdvancedWithout.value);
    var titel = trimAll(form.titel.value);
    var auteur = trimAll(form.auteur.value);
    var jaartal = trimAll(form.jaartal.value);
    var jaartalopties = trimAll(form.jaartalopties.value);

    form.AdvancedAnd.value = advancedAnd;
    form.AdvancedOr.value = advancedOr;
    form.AdvancedPhrase.value = advancedPhrase;
    form.AdvancedWithout.value = advancedWithout;
    form.titel.value = titel;
    form.auteur.value = auteur;
    form.jaartal.value = jaartal;

    if(advancedAnd == '' && advancedOr == '' && advancedPhrase == '' && advancedWithout == '' && titel == '' && auteur == '' && jaartal == '') {
       alert('U dient minimaal 1 zoekveld in te vullen.');
       form.AdvancedAnd.focus();
       return false;
    }
    
    if(!checkSelection(document.getElementById('form2').products)) {
        toggleBox('advanced_search',0);
        return false;
    } 
}

function trimAll(sString) {
    while (sString.substring(0,1) == ' ' || sString.substring(0,1) == ',') {
        sString = sString.substring(1, sString.length);
    }
    while (sString.substring(sString.length-1, sString.length) == ' ' || sString.substring(sString.length-1, sString.length) == ',') {
        sString = sString.substring(0,sString.length-1);
    }
    return sString;
}

function checkAll(field) {
    for (i = 0; i < field.length; i++) {
        field[i].checked = true;
    }
}

function uncheckAll(field) {
    for (i = 0; i < field.length; i++) {
        field[i].checked = false;
    }
}

function copyEditions(field, toField) {        
    if(field.length > 0) {
        var products = '';            
        for (i = 0; i < field.length; i++) {	            
            if(field[i].checked) {
                products += field[i].value+';';	                
            }
        }
        toField.value = products;
    }
}

function checkSelection(field) {        
    if(field.length > 0) {
        for (i = 0; i < field.length; i++) {	            
            if(field[i].checked) {
                return true;
            }
        }
        alert('U heeft geen uitgaven aangevinkt.\nKies a.u.b. één of meerdere uitgave(n)');
        return false;
    }
    return true;
}

function addInputSubmitEvent(form, input) {
    input.onkeydown = function(e) {
        e = e || window.event;
        if (e.keyCode == 13) {
            form.submit();
            return false;
        }
    };
}

window.onload = function() {
    var forms = document.getElementsByTagName('form');

    for (var i=0;i < forms.length;i++) {
        var inputs = forms[i].getElementsByTagName('input');

        for (var j=0;j < inputs.length;j++)
            addInputSubmitEvent(forms[i], inputs[j]);
    }
};