var presentation = ["<phrase>Imagine being a crew member, hundreds of years ago, sailing in southern waters. Your captain is searching for food while exploring unfamiliar waters. Your job is to watch the sea off the ship's side for ice, guiding the pilot to avoid a wreck. White, floating ice in a dark-blue ocean stretches as far as you can see. The wind is cold on your face. Alongside the ship, a fish darts past. Another slows to a stop and raises its head above the water to look at you. How could a fish do that?<\/phrase>","<word>fish with feathers or swimming birds<\/word>","<word>birds that developed the ability to swim<\/word>","<phrase>Did the sailors see <strong data-readahead=\"fish with feathers or swimming birds\" class=\"presentation_word\">fish with feathers or swimming birds<\/strong>? Today, we know that the sailors saw <strong data-readahead=\"birds that developed the ability to swim\" class=\"presentation_word\">birds that developed the ability to swim<\/strong>. Their wings became flippers, and they could \"fly\" through the water with amazing agility.<\/phrase>","<word>17 types of penguins<\/word>","<word>Adelie penguins<\/word>","<word>Emperor penguins<\/word>","<phrase>Sometimes, people joke that there are two types of penguins-the black ones walking away from you and the white ones walking toward you! In fact, there are <strong data-readahead=\"17 types of penguins\" class=\"presentation_word\">17 types of penguins<\/strong>. Only two kinds raise their young on the continent of Antarctica. <strong data-readahead=\"Adelie penguins\" class=\"presentation_word\">Adelie penguins<\/strong> grow to 29 inches tall and have a white ring around each eye. <strong data-readahead=\"Emperor penguins\" class=\"presentation_word\">Emperor penguins<\/strong> have yellow-orange coloring near their necks. Standing about 35 inches tall, they are the tallest penguins living today.<\/phrase>","<word>Emperor penguins<\/word>","<word>portable nests<\/word>","<phrase><strong data-readahead=\"Emperor penguins\" class=\"presentation_word\">Emperor penguins<\/strong> have <strong data-readahead=\"portable nests\" class=\"presentation_word\">portable nests<\/strong>-the tops of their feet. Father <strong data-readahead=\"Emperor penguins\">Emperor penguins<\/strong> keep the egg on top of their feet for more than two months, until the egg is ready to hatch. The mother penguin goes out for food during this time. Imagine holding an egg on your feet for two months until someone returns with the groceries!<\/phrase>","<word>good parents<\/word>","<word>a creche<\/word>","<word>1,000 fluffy chicks<\/word>","<phrase>Male and female penguins are both <strong data-readahead=\"good parents\" class=\"presentation_word\">good parents<\/strong>. Once the chicks hatch, both parents travel long distances to find food for them in the sea. When chicks are big enough to be left alone, they huddle together in a group, called <strong data-readahead=\"a creche\" class=\"presentation_word\">a creche<\/strong> (pronounced \"kresh\"), to keep warm. Sometimes, <strong data-readahead=\"a creche\">a creche<\/strong> contains more than <strong data-readahead=\"1,000 fluffy chicks\" class=\"presentation_word\">1,000 fluffy chicks<\/strong>.<\/phrase>","<word>storing so much food in their tummies<\/word>","<phrase>It may be days before the parents return and the chicks eat again. When they return with food, the fun really begins. Chicks chase their parents, begging for food. Penguin chicks eat huge amounts at one time, <strong data-readahead=\"storing so much food in their tummies\" class=\"presentation_word\">storing so much food in their tummies<\/strong> that they look like sagging bags of laundry!<\/phrase>","<word>forcing the children to grow up<\/word>","<phrase>Eventually, the adult penguins stop feeding the chicks. This is nature's way of <strong data-readahead=\"forcing the children to grow up\" class=\"presentation_word\">forcing the children to grow up<\/strong>. When the penguin chicks are hungry enough, they find their way to the sea. Without any swimming lessons, they make their way into the icy waters, and they swim as only penguins do.<\/phrase>"];
	var currentPosition = 0;
	var totalPositions = 0;
	var timePerWord = 1500;
	var timePerPhraseWord = 120
	var readAheadPlayerTimer;
	var autoPlay = true;
	var setMinimized = false;

	var wordSpeedOptions = {'Slower':2000,'Moderate':1200,'Fast':800};
	var phraseSpeedOptions = {'Slower':280,'Moderate':200,'Fast':80};
	var defaultWordSpeedOption = 'Moderate';
	var defaultPhraseSpeedOption = 'Moderate';
	var logToLTI = false;

	$(window).load(function(){
		totalPositions = presentation.length;
		if (totalPositions > 0){
			$('body').prepend('<div id="read_ahead_player_back"></div>');
			$('body').prepend('<div id="read_ahead_player"></div>');
			$('#read_ahead_player').prepend('<div id="read_ahead_player_field" class="read_ahead_word_section"></div>');
			initializeReadAheadControls();
			initializeReadAheadSlider();
			initializeReadAheadSpeedOptions();
			currentReadAheadControls();
			resumeReadAheadPlayback();
		}
	});

	$(document).keyup(function(e){
		switch(e.which) {
			case 37: 
				pauseReadAheadPresentation();
				priorReadAheadPresentationItem();
				break;
			case 39:
				pauseReadAheadPresentation();
				nextReadAheadPresentationItem();
				break;
			default:
				break;
		}

	});

	function initializeReadAheadControls(){
		var s = '';
		s += '<a href="javascript:void(0)" onclick="read_ahead_switch_min_max(true);" id="read_ahead_player_max_min" class="player-icons" aria-label="minimize/maximize player">';
		s += '<span class="fa-stack fa-lg " aria-hidden><i class="fa fa-circle fa-stack-2x"></i><i class="fa fa-minus fa-stack-1x fa-inverse"></i></span>';
		s += '</a>';
		s += '<div id="read_ahead_controls">';
		s += '<a href="javascript:void(0)" onclick="priorReadAheadPresentationItem()" id="read_ahead_player_previous_word" class="player-icons" aria-label="previous keyword">';
		s += '<span class="fa-stack fa-lg " aria-hidden><i class="fa fa-circle fa-stack-2x"></i><i class="fa fa-backward fa-stack-1x fa-inverse"></i></span>';
		s += '</a>';
		s += '<a href="javascript:void(0)" onclick="pauseReadAheadPresentation()" id="read_ahead_player_pause_play" class="player-icons" aria-label="play/pause">';
		s += '<span class="fa-stack fa-lg " aria-hidden><i class="fa fa-circle fa-stack-2x"></i><i class="fa fa-pause fa-stack-1x fa-inverse"></i></span>';
		s += '</a>';
		s += '<a href="javascript:void(0)" onclick="nextReadAheadPresentationItem()" id="read_ahead_player_next_word" class="player-icons" aria-label="next keyword">';
		s += '<span class="fa-stack fa-lg " aria-hidden><i class="fa fa-circle fa-stack-2x"></i><i class="fa fa-forward fa-stack-1x fa-inverse"></i></span>';
		s += '</a>';
		s += '</div>';
		$('#read_ahead_player').append(s);
	}

	function initializeReadAheadSlider(){
		var s = '';
		s += '<div class="read_ahead_slider" id="readAheadSlider">';
		s += '<div class="read_ahead_slider_bar" id="readAheadSliderBar"></div>';
		s += '</div>';
		$('#read_ahead_controls').prepend(s);
		updateReadAheadSliderPosition();
	}

	function initializeReadAheadSpeedOptions(){
		var s = '<div id="read_ahead_player_options">';
		s += '<div class="slider_control" id="slider_control_word_speed">';
		s += ' Word Speed<br/>';
		s += '<div class="slider_bar">';
		optionCount = 0;
		for (index in wordSpeedOptions) { optionCount++; }
		optionWidth = 100 / optionCount;
		for (index in wordSpeedOptions) {
			var option = wordSpeedOptions[index];
			if (index == defaultWordSpeedOption) {
				s += '<a href="javascript:void(0)" id="slider_control_word_speed_'+option+'" onclick="updateReadAheadWordSpeed('+option+',this)" style="width:'+optionWidth+'%;" title="'+index+'" data-speed="'+option+'" class="current_speed" aria-label="'+index+'"></a>';
				updateReadAheadWordSpeed(option);
			} else {
				s += '<a href="javascript:void(0)" id="slider_control_word_speed_'+option+'" onclick="updateReadAheadWordSpeed('+option+',this)" style="width:'+optionWidth+'%;" title="'+index+'" data-speed="'+option+'" aria-label="'+index+'"></a>';
			}
		}
		s += '</div>';
		s += '</div>';
		s += '<div class="slider_control" id="slider_control_phrase_speed">';
		s += ' Phrase Speed<br/>';
		s += '<div class="slider_bar">';
		optionCount = 0;
		for (index in phraseSpeedOptions) { optionCount++; }
		optionWidth = 100 / optionCount;
		for (index in phraseSpeedOptions) {
			var option = phraseSpeedOptions[index];
			if (index == defaultWordSpeedOption) {
				s += '<a href="javascript:void(0)" id="slider_control_phrase_speed_'+option+'" onclick="updateReadAheadPhraseSpeed('+option+',this)" style="width:'+optionWidth+'%;" title="'+index+'" data-speed="'+option+'" class="current_speed" aria-label="'+index+'"></a>';
				updateReadAheadPhraseSpeed(option);
			} else {
				s += '<a href="javascript:void(0)" id="slider_control_phrase_speed_'+option+'" onclick="updateReadAheadPhraseSpeed('+option+',this)" style="width:'+optionWidth+'%;" title="'+index+'" data-speed="'+option+'" aria-label="'+index+'"></a>';
			}
		}
		s += '</div>';
		s += '</div>';
		s += '</div>';
		$('#read_ahead_controls').append(s);
	}

	function updateReadAheadWordSpeed(microseconds,sender) {
		microseconds = microseconds != undefined && microseconds > 0 ? microseconds : 0;
		if (microseconds > 0) { timePerWord = microseconds; }
		if (sender!=undefined) { 
			$('#slider_control_word_speed').find('a').removeClass('current_speed');
			$(sender).addClass('current_speed');
		}
		logReadAheadPlayerAction('updateReadAheadWordSpeed','Presentation',microseconds);
	}

	function updateReadAheadPhraseSpeed(microseconds,sender) {
		microseconds = microseconds != undefined && microseconds > 0 ? microseconds : 0;
		if (microseconds > 0 ) { timePerPhraseWord = microseconds; }
		if (sender!=undefined) { 
			$('#slider_control_phrase_speed').find('a').removeClass('current_speed');
			$(sender).addClass('current_speed');
		}
		logReadAheadPlayerAction('updateReadAheadPhraseSpeed','Presentation',microseconds);
	}

	function updateReadAheadSliderPosition(){
		var currentSliderBarWidth = 100 - (100 / totalPositions * (currentPosition + 1));
		$('#readAheadSliderBar').css('width',currentSliderBarWidth+'%');
	}

	function currentReadAheadControls(){
		$('#read_ahead_player_pause_play').show();
		if (currentPosition < totalPositions - 1)	{
			$('#read_ahead_player_next_word').removeClass('disabled');
		} else {
			$('#read_ahead_player_next_word').addClass('disabled');
		}
		if (currentPosition > 0) {
			$('#read_ahead_player_previous_word').removeClass('disabled');
		} else {
			$('#read_ahead_player_previous_word').addClass('disabled');
		}
	}

	function restartReadAheadPresentation(){
		currentPosition = 0;
		logReadAheadPlayerAction('restartReadAheadPresentation','Presentation','');
		resumeReadAheadPlayback();
	}

	function resumeReadAheadPlayback(){
		$('.fa-repeat').removeClass('fa-repeat').addClass('fa-play');
		$('#read_ahead_player_pause_play').each(function(){
			$(this).find('.fa-play').removeClass('fa-play').addClass('fa-pause');
			$(this).off('click');
			$(this).attr('onclick','pauseReadAheadPresentation()');
		});
		logReadAheadPlayerAction('resumeReadAheadPlayback','Presentation','');
		playReadAheadPresentation();
	}

	function pauseReadAheadPresentation(){
		$('#read_ahead_player_pause_play').each(function(){
			$(this).find('.fa-pause').removeClass('fa-pause').addClass('fa-play');
			$(this).off('click');
			$(this).attr('onclick','resumeReadAheadPlayback()');
		});
		logReadAheadPlayerAction('pauseReadAheadPresentation','Presentation','');
		read_ahead_pause();
	}

	function endReadAheadPresentation(){
		$('.fa-play').removeClass('fa-play').addClass('fa-repeat');
		$('.fa-pause').removeClass('fa-pause').addClass('fa-repeat');
		$('#read_ahead_player_pause_play').each(function(){
			$(this).off('click');
			$(this).attr('onclick','restartReadAheadPresentation()');
		});
		logReadAheadPlayerAction('endReadAheadPresentation','Presentation','');
		logLTIEndPresentation();
	}

	function playReadAheadPresentation(){
		autoPlay=true;
		currentPosition--;
		logReadAheadPlayerAction('playReadAheadPresentation','Presentation','');
		nextReadAheadPresentationItem(); 
	}

	function startReadAheadStepper(timeDisplayWord){
		clearInterval(readAheadPlayerTimer);
		readAheadPlayerTimer = setTimeout(function() { read_ahead_step(); },timeDisplayWord);
	}

	function stopReadAheadStepper(){
		clearInterval(readAheadPlayerTimer);
	}

	function read_ahead_step(){
		if (autoPlay) {
			nextReadAheadPresentationItem();
		}
	}

	function read_ahead_pause(){
		autoPlay=false;
		stopReadAheadStepper();
	}

	function showReadAheadPresentationItem(index){
		currentPosition = index;
		currentPresentationItem = presentation[currentPosition] != undefined ? presentation[currentPosition].trim() : "";
		if (currentPresentationItem != "") {
			currentItemWordCount = presentation[currentPosition].replace("\n","").split(" ").length;
			if (currentPresentationItem.startsWith("<word>")){
				startReadAheadStepper(currentItemWordCount*timePerWord);
				$('#read_ahead_player_field').html('<div class="read_ahead_word" style="display:block;">'+currentPresentationItem+'</div>');
				logReadAheadPlayerAction('showReadAheadPresentationItem','Word',currentPresentationItem);
		
			} else {
				startReadAheadStepper(currentItemWordCount*timePerPhraseWord);
				$('#read_ahead_player_field').html('<div class="read_ahead_text_box" style="display:block;"><div class="read_ahead_text">'+currentPresentationItem.replace("\n","<br />")+'</div></div>');
				logReadAheadPlayerAction('showReadAheadPresentationItem','Phrase','');
		
			}
		} else {
			if (currentPosition < totalPositions) {
				nextReadAheadPresentationItem();
			} else {
				endReadAheadPresentation();
				read_ahead_minimize();
			}
		}
		currentReadAheadControls();
		updateReadAheadSliderPosition();
		saveReadAheadPosition();
	}

	function priorReadAheadPresentationItem(){
		stopReadAheadStepper();
		logReadAheadPlayerAction('priorReadAheadPresentationItem','Controls','');
		showReadAheadPresentationItem(currentPosition-1);
	}


	function nextReadAheadPresentationItem(){
		stopReadAheadStepper();
		logReadAheadPlayerAction('nextReadAheadPresentationItem','Controls','');
		showReadAheadPresentationItem(currentPosition+1);
	}

	function read_ahead_playAgain(){
		currentWordIndex = 0;
		logReadAheadPlayerAction('read_ahead_playAgain','Controls','');
		playReadAheadPresentation();
	}


	function read_ahead_minimize(){
		setMinimized = true;
		logReadAheadPlayerAction('read_ahead_minimize','Controls','');
		read_ahead_switch_min_max();
	}

	function read_ahead_maximize(){
		setMinimized = false;
		logReadAheadPlayerAction('read_ahead_maximize','Controls','');
		read_ahead_switch_min_max();
	}

	function read_ahead_switch_min_max(forceSwitch){
		forceSwitch = forceSwitch != undefined ? forceSwitch : false;
		if (forceSwitch) { setMinimized = !setMinimized; }

		if (setMinimized) {
			$('#read_ahead_player_back').fadeOut();
			$('#read_ahead_player').addClass('minimize');
			$('.player-icons .fa-stack').removeClass('fa-lg').addClass('fa-sm');
			$('.player-icons .fa-minus').removeClass('fa-minus').addClass('fa-expand');
			logReadAheadPlayerAction('read_ahead_switch_min_max','Min','');
			//$('#read_ahead_player_max_min').each(function(){
			//	$(this).off('click');
			//	$(this).attr('onclick','read_ahead_maximize()');
			//});
		} else {
			$('#read_ahead_player_back').fadeIn();
			$('#read_ahead_player').removeClass('minimize');
			$('.player-icons .fa-stack').removeClass('fa-sm').addClass('fa-lg');
			$('.player-icons .fa-expand').removeClass('fa-expand').addClass('fa-minus');
			logReadAheadPlayerAction('read_ahead_switch_min_max','Max','');
			//$('#read_ahead_player_max_min').each(function(){
			//	$(this).off('click');
			//	$(this).attr('onclick','read_ahead_minimize()');
			//});
		}

	}

	function saveReadAheadPosition(){
		$.ajax({
			type:'POST',
			url:'/ajax/save_user_presentation_position.php',
			data: { 'id':1779,
					'position': currentPosition
				}
		})
		.done(function(results){
		})
		.fail(function( jqXHR, textStatus ) {
			alert( "Request failed: " + textStatus );
		});

	}

	function logLTIEndPresentation(action) {
		if (!logToLTI) {
			return;
		}

		$.ajax({
			type:'POST',
			url:'/lti/presentationEnded.php',
			data: { 'documentId':1779,
					'userId':0,
				}
		})
	}

	function logReadAheadPlayerAction(action,area,details){
		var d = new Date();
		var t = d.getTime();
		action = action != undefined ? action.trim() : 'UNKNOWN';
		area = area != undefined ? area.trim() : '';
		details = details != undefined ? details : '';

		// If we are about to show a new word, increase the number of keywords
		// reinforced so we can log that for the Dashboard page.
		if (area == 'Word') {
			window.keywordCount++;
		}

		$.ajax({
			type:'POST',
			url:'/logging/logPlayerAction.php',
			data: { 'documentId':1779,
					'userId':0,
					'playerAction':action,
					'playerArea':area,
					'details':details,
					'timestamp': t
				}
		})
		.done(function(results){
		})
		.fail(function( jqXHR, textStatus ) {
			alert( "Request failed: " + textStatus );
		});

	}