var decimalPlaces = 0;

function calculateScore()
{
    var iScore = 0;
    var dPercent = 0;
    for (iQuestion = 1; iQuestion <= 13; iQuestion++)
    {
        if(!(isYesSelected(iQuestion)||isNoSelected(iQuestion)))
        {
            alert('Please answer all of the questions.');
            iScore = -1;
            break;
        }
        if(isYesSelected(iQuestion)) iScore++;
    }
    if(iScore!=-1)
    {   
        dPercent = roundNumber(iScore/0.13, decimalPlaces);
        getElement('spanScore').innerHTML = iScore;
        getElement('spanPercent').innerHTML = dPercent;
        getElement('divScore').style.display = 'block';
        switch(true)
        {
            case(dPercent==0):
                getElement('divResult4').style.display = 'block'
                break;
            case((dPercent>0)&&(dPercent<25)):
                getElement('divResult3').style.display = 'block'
                break;
            case((dPercent>=25)&&(dPercent<=50)):
                getElement('divResult2').style.display = 'block'
                break;
            case(dPercent>50):
                getElement('divResult1').style.display = 'block'
                break;
            default:
                alert('An error occurred. Please reload the page and try again.')
        }
        for (iQuestion = 1; iQuestion <= 13; iQuestion++)
        {
            getYesOption(iQuestion).disabled = true;
            getNoOption(iQuestion).disabled = true;
        }
        getElement('btnCalculate').disabled = true;
        getElement('divReset').style.display = 'block';
    }
}

function resetQuestions()
{
    for (iQuestion = 1; iQuestion <= 13; iQuestion++)
    {
        getYesOption(iQuestion).disabled = false;
        getYesOption(iQuestion).checked = false;
        getNoOption(iQuestion).disabled = false;
        getNoOption(iQuestion).checked = false;
    }
    getElement('btnCalculate').disabled = false;
    getElement('divScore').style.display = 'none';
    getElement('divResult1').style.display = 'none'
    getElement('divResult2').style.display = 'none'
    getElement('divResult3').style.display = 'none'
    getElement('divResult4').style.display = 'none'
    getElement('divReset').style.display = 'none';
}

function isYesSelected(iQuestion)
{
    return getYesOption(iQuestion).checked;
}

function isNoSelected(iQuestion)
{
    return getNoOption(iQuestion).checked;
}

function getYesOption(iQuestion)
{
    return getElement('radQ'+iQuestion+'Y');
}

function getNoOption(iQuestion)
{
    return getElement('radQ'+iQuestion+'N');
}

function getElement(sId)
{
    return document.getElementById(sId);
}

function roundNumber(dNumber, iPlaces)
{
	var dResult;
	if (dNumber > 8191 && dNumber < 10485) 
	{
		dNumber = dNumber - 5000;
		dResult = Math.round(dNumber*Math.pow(10,iPlaces))/Math.pow(10,iPlaces);
		dResult = dResult + 5000;
	} 
	else
	{
		dResult = Math.round(dNumber*Math.pow(10,iPlaces))/Math.pow(10,iPlaces);
	}
	return dResult;
}