function checkDate(arrivalOrDeparture)
{
    if (!arrivalOrDeparture) {
        var ddPrefix="a"
    } else {
        var ddPrefix="d"
    }
    var dateSelect = document.forms.datesForm.elements[ddPrefix+"D"]
}

// arrivalOrDeparture is a boolean: 0=arr; 1=dep
function refreshWeekday(arrivalOrDeparture)
{
    if (!arrivalOrDeparture) {
        var ddPrefix="a"
		var outputText= "Llegada:"
        var labelDivId="arriving"
    } else {
        var ddPrefix="d"
        var outputText= "Salida:"
        var labelDivId="leaving"
    }
    var weekdaysArray = new Array("Domingo","Lunes","Martes","Miércoles","Jueves","Viernes","Sábado");
    var els = document.forms.datesForm.elements
    var thisDate = selectedDate(els, ddPrefix)
    if (!isNaN(thisDate) && typeof(thisDate.getDay()) != "undefined") {
        rewriteText(labelDivId, outputText+' <strong>'+weekdaysArray[thisDate.getDay()]+'</strong>')
    } else {
        rewriteText(labelDivId, outputText)
    }
}


function rewriteText(divId, text) {
    if (document.layers) {
        var obj = document.layers[divId].document;
        obj.open();
        obj.write(text);
        obj.close();
    }
    else if (document.all) {
        document.all[divId].innerHTML = text;
    }
    else if (document.documentElement) {
        document.getElementById(divId).innerHTML = text;
    }
}

function selectedDate(els, ddPrefix) {
    var monthYear = els[ddPrefix+"MY"].options[els[ddPrefix+"MY"].selectedIndex].value
    dateList = monthYear.split('-')
    chosenMonth = parseInt(dateList.shift())
    chosenYear = parseInt(dateList.shift())
    var chosenDay = parseInt(els[ddPrefix+"D"].options[els[ddPrefix+"D"].selectedIndex].value)
    if (isNaN(chosenDay)) { return chosenDay}
    var thisDate = new Date(chosenYear, chosenMonth-1, chosenDay, 0, 0, 0, 0)
    return (thisDate)
    }

function updateDepartureDropdown(langCode) {
    checkDate(0);
    var els = document.forms.datesForm.elements
    var newArrDate = selectedDate(els, "a")
    var newDepDate = new Date(newArrDate.getFullYear(), newArrDate.getMonth(), newArrDate.getDate()+1)
    document.getElementById('dD').selectedIndex = newDepDate.getDate();
    var depMonthYear = els['dMY']
    
    for (var i=0; i < depMonthYear.options.length; i++ ) {
        dateString = depMonthYear.options[i].value
        dateList = dateString.split('-')
        month = dateList.shift()
        year = dateList.shift()
        if (month == newDepDate.getMonth() + 1) {
            if (year == newDepDate.getFullYear()) {
            document.getElementById('dMY').selectedIndex = i
            break }
            } 
        }
    refreshWeekday(1,langCode);            
    }

function refreshWeekdays(langCode) {
    refreshWeekday(0,langCode);
    refreshWeekday(1,langCode);
    }