function gebi(id){
	return document.getElementById(id);
}

function cr_change(id) {
	var cr_sel = gebi('cr_select');
	var new_item_id = id ? id : cr_sel.value;
	if (cr_sel) {
		var new_select = 0;
		for (i=0; i<cr_rate.length; i++) {
			var obj = gebi('cr_'+cr_rate[i].id);
			if (obj) obj.className = '';
			if (cr_rate[i].id == new_item_id) {
				new_select = i;
			}
		}
		var active = gebi('cr_'+new_item_id);
		if (active) active.className = 'choosen';
		cr_sel.selectedIndex = new_select;
		gebi('cr_rate').innerHTML = cr_rate[new_select].rate;
		gebi('cr_title').innerHTML = cr_rate[new_select].title;
		gebi('cr_unit').innerHTML = cr_rate[new_select].unit;
	}
}

function trim0(str) {
	return str.replace(/0*$/, '').replace(/\.*$/, '');
}

function de_money(str) {
	if (lang == 'de') {
		return str.replace(/\./, ',');
	} else {
		return str.replace(/\,/, '.');
	}
}

function recalc_unit() {
	var obj = gebi('amount');
	if (!obj) return true;
	var v = obj.value;
	if (v.match(/[^0-9.,]/)) v = v.replace(/[^0-9,].*$/, '');
	v = v.replace(/,/, '.');
	v = (isNaN(v) || v <= 0) ? 0 : (rate * (1.0*v).toFixed(2)).toFixed(2);
	gebi('unit').value = v ? de_money(trim0(v)) : '';
}

function recalc_amount() {
	var obj = gebi('unit');
	if (!obj) return true;
	var v = obj.value;
	if (v.match(/[^0-9.,]/)) v = v.replace(/[^0-9,].*$/, '');
	v = v.replace(/,/, '.');
	v = (isNaN(v) || v <= 0) ? 0 : ((1.0*v).toFixed(2) / rate).toFixed(2);
	gebi('amount').value = v ? de_money(trim0(v)) : '';
}