var currentQuestion = -1;
var testTitle = "";		
var inProgress = false;
var userName = "";
var questions = new Array();
var answersReceived = new Array();
var main = window;
window.onload=init;

function Question() {
	this.answers = new Array();
	this.text = "";
	this.type = "";
	this.page = "";
	this.rat = "";
	this.correctIndex = -1;
	
	this.setText = Question_setText;
	this.getText = Question_getText;
	this.setType = Question_setType;
	this.getType = Question_getType;
	this.setPage = Question_setPage;
	this.getPage = Question_getPage;
	this.setRationale = Question_setRationale;
	this.getRationale = Question_getRationale;
	this.setCorrectAnswer = Question_setCorrectAnswer;
	this.getCorrectAnswer = Question_getCorrectAnswer;
	this.addAnswer = Question_addAnswer;
	
}
function Question_setText(atext) {
	this.text = atext;
}
function Question_getText() {
	return this.text;
}
function Question_setType(atype) {
	this.type = atype;
}
function Question_getType() {
	return this.type;
}

function Question_setPage(apage) {
	this.page = apage;
}
function Question_getPage() {
	return this.page;
}
function Question_setRationale(arat) {
	this.rat = arat;
}
function Question_getRationale() {
	return this.rat;
}
function Question_setCorrectAnswer(aindex) {
	this.correctIndex = aindex;
}
function Question_getCorrectAnswer() {
	return this.correctIndex;
}
function Question_addAnswer(aanswer) {
	this.answers[this.answers.length] = aanswer;
}

function addQuestion(question) {
	questions[questions.length] = question;
}

function init() {
	if (questions.length > 0) {
		answersReceived = new Array(questions.length);
		currentQuestion = 0;
		inProgress = true;	
	}
}

function displayQuestion() {
	if (main.questions.length > 0) {
		var question = questions[currentQuestion];
		
		TestPanel.questionNumber.innerHTML="Question " + (currentQuestion+1) + " out of " + questions.length;
		TestPanel.section.innerHTML = question.getText();
		if (question.getType() == "tf") {
			TestPanel.panel.innerHTML = '<form name=answer><TABLE cellpadding=5 cellspacing=5 border=0><TR><TD><INPUT TYPE="radio" NAME="radioAnswer" ' +
			((answersReceived[currentQuestion] == 0)?"CHECKED":"") +
			'></TD><TD>True</TD></TR><TR><TD><INPUT TYPE="radio" NAME="radioAnswer" ' +
			((answersReceived[currentQuestion] == 1)?"CHECKED":"") +
			'></TD><TD>False</TD></TR></TABLE></form>';
		} else if (question.getType() == "mc" || question.getType() == "g") {
			var answers = question.answers;
			var html = "<form name=answer><TABLE cellpadding=5 cellspacing=5 border=0>";
			for (var i=0; i < answers.length; i++) {
				html += '<TR><TD><INPUT TYPE="radio" NAME="radioAnswer" ' + 
				((answersReceived[currentQuestion] == i)?"CHECKED":"") +'></TD><TD>' + answers[i] +"</TD></TR>";
			}
			html += "</TABLE></form>";
			TestPanel.panel.innerHTML = html;
		} else if (question.getType() == "sa") {
			var answers = question.answers;
			var html =  "<form name=answer>" + question.text + "</form>";
			for (var i=0; i < answers.length; i++) {
				textBox = '<INPUT TYPE="text" NAME="textAnswer' + i + '" VALUE="' + 
				((!answersReceived[currentQuestion])?"":answersReceived[currentQuestion][i]) +'">';
				html = html.replace(/\_+/, textBox);
			}
			TestPanel.panel.innerHTML = html;
		}
	}
}

function nextQuestion() {
	if (inProgress) {
		if (recordAnswer()) {
			if (currentQuestion < questions.length - 1) {
				currentQuestion++;
				displayQuestion();
			} else {
				calculateScore();
			}
		} else {
			alert("Please provide answer to proceed.\nYou can use the \"Back\" button to review or change your answers");
		}
	}
}

function previousQuestion() {
	if (inProgress) {
		recordAnswer();
		if (currentQuestion > 0)
			currentQuestion--;
		displayQuestion();
	}
}

function recordAnswer() {
	var bGotAnswer = false;
	var question = questions[currentQuestion];
	if (question.type == "mc" || question.type == "g") {
		for (var i=0; i < question.answers.length; i++) {
			if (TestPanel.answer.radioAnswer[i].checked) {
				answersReceived[currentQuestion] = i;
				bGotAnswer = true;
			}
				
		}
	} else
	if (question.type == "tf") {
		for (var i=0; i < 2; i++) {
			if (TestPanel.answer.radioAnswer[i].checked) {
				answersReceived[currentQuestion] = i;
				bGotAnswer = true;
			}

		}
	} else {
		answersReceived[currentQuestion] = new Array();
		for (var i=0; i < question.answers.length; i++) {
			answersReceived[currentQuestion][i] = 
				TestPanel.answer.elements["textAnswer" + i].value;
			bGotAnswer = true;
		}
	}
	return bGotAnswer;
}

function calculateScore() {
	inProgress= false;
	
	var count = 0;
	var countTotal = 0;
	var result = "";
	var emailBody = "";
	
	for (var i = 0; i < questions.length; i++) {
		var question = questions[i];
		result += (i + 1) + ". " + question.text + "<P>";
		emailBody += (i + 1) + ". " + question.text + "\n";
		if (question.type == "mc" || question.type == "g") {
			var correctAnswer = question.getCorrectAnswer();
			var userAnswer = answersReceived[i];
			result += "Your answer: <B>" + ((!question.answers[userAnswer])?"":question.answers[userAnswer]) + "</B><BR>";
			result += "Correct answer: <B>" + question.answers[correctAnswer] + "</B><BR>";
			if (correctAnswer == userAnswer) {
				result += '<IMG SRC="check.gif"><SPAN class=correct>Correct</SPAN>';
				emailBody += "+ ";
				count++;
			} else {
				emailBody += "- ";
				result += '<IMG SRC="wrong.gif"><SPAN class=incorrect>Incorrect</SPAN>';
			}
			result += "<P>";
			emailBody += ((question.answers[userAnswer])?"":question.answers[userAnswer]);
			countTotal++;
		} else
		if (question.type == "tf") {
			var correctAnswer = question.getCorrectAnswer();
			var userAnswer = answersReceived[i];
			result += "Your answer: <B>" + ((userAnswer==0)?"True":((userAnswer==1)?"False":"")) + "</B><BR>";
			result += "Correct answer: <B>" + ((correctAnswer==0)?"True":"False") + "</B><BR>";
			if (correctAnswer == userAnswer) {
				result += '<IMG SRC="check.gif">';
				emailBody += "+ ";
				count++;
			} else {
				result += '<IMG SRC="wrong.gif"><BR><U>Rationale</U><I>: ' + question.rationale + '</I>';
				emailBody += "- ";
			}
			result += "<P>";
			emailBody += ((userAnswer==0)?"True":((userAnswer==1)?"False":""));
			countTotal++;
		} else
		if (question.type == "sa") {
			var userAnswers = answersReceived[i];
			var userAnswer = "";
			for (var j=0; j < userAnswers.length; j++) {
				if (userAnswer == "") {
					userAnswer = userAnswers[j]
				} else {
					userAnswer += ", " + userAnswers[j]
				}
			}
			result += "Your answer: <B>" + userAnswer + "</B><BR>";

			var correctAnswer = "";
			for (var j=0; j < question.answers.length; j++) {
				if (correctAnswer == "") {
					correctAnswer = question.answers[j]
				} else {
					correctAnswer += ", " + question.answers[j]
				}
			}
			result += "Correct answer: <B>" + correctAnswer + "</B><BR>";

			if (correctAnswer.toUpperCase() == userAnswer.toUpperCase()) {
				result += '<IMG SRC="check.gif">';
				emailBody += "+ ";
				count++;
			} else {
				result += '<IMG SRC="wrong.gif"><BR><U>Rationale</U><I>: ' + question.rationale + '</I>';
				emailBody += "- ";
			}
			result += "<P>";
			emailBody += userAnswer;
			countTotal++;
		}
		emailBody += "\n\n";
	}
	result += "<TABLE BORDER=1 CELLPADDING=10><TR><TD>Correct: <B>" + count + "</B> out of " + countTotal + "&nbsp;&nbsp;&nbsp;&nbsp;" + (Math.round(100 * count/countTotal)) + "%</TD></TR></TABLE>";
	TestPanel.buttons.innerHTML = "You may now exit your browser or go to a different page."; 
	if (main.showScore) {
		TestPanel.questionNumber.innerHTML="Correct: " + count + " out of " + countTotal + "&nbsp;&nbsp;&nbsp;&nbsp;" + (Math.round(100 * count/countTotal)) + "%" + "<BR><BR>You have completed this test! Your score and results summary are displayed below. Please print this page for your records. If your instructor chose to receive your test results via e-mail, they have been automatically submitted.";
		TestPanel.section.innerHTML = result;
		TestPanel.panel.innerHTML = "";
	} else {
		
		TestPanel.questionNumber.innerHTML = "You have completed this test";
		TestPanel.section.innerHTML = "You have completed this test! Your test results have been automatically scored and submitted to your instructor via e-mail";
		TestPanel.panel.innerHTML = "";
	}

	emailBody = testTitle + "\n" +
		"Student: " + userName + "\n" +
		"Correct: " + count + " out of " + countTotal + " " + (Math.round(100 * count/countTotal)) + "%\n\n" +
		emailBody;
	sendEmail(emailBody);
}
function sendEmail(emailBody) {
	PROCESSOR.document.forms["MAIL"].ToName.value=testAuthor;
	PROCESSOR.document.forms["MAIL"].ToEmail.value=testAuthorEmail;
	PROCESSOR.document.forms["MAIL"].Subject.value="Test Result: " + userName;
	PROCESSOR.document.forms["MAIL"].BodyText.value=emailBody;
	/*
	alert(
		"To: " + PROCESSOR.document.forms["MAIL"].ToName.value + 
		" <" + PROCESSOR.document.forms["MAIL"].ToEmail.value + ">" +
		"\nSubject: " + PROCESSOR.document.forms["MAIL"].Subject.value + 
		"\nBody: " + PROCESSOR.document.forms["MAIL"].BodyText.value
	);
	*/
	PROCESSOR.document.forms["MAIL"].submit();
}
function authenticate(fname,lname)
{
	main.userName = fname + " " + lname;
	TestPanel.location.href = "test.html";
}