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<!doctype html>
<html lang="en">
	<head>
		<meta charset="utf-8">

		<title>reveal.js - Slide Notes</title>

		<style>
			body {
				font-family: Helvetica;
			}

			#current-slide,
			#upcoming-slide,
			#speaker-controls {
				padding: 6px;
				box-sizing: border-box;
				-moz-box-sizing: border-box;
			}

			#current-slide iframe,
			#upcoming-slide iframe {
				width: 100%;
				height: 100%;
				border: 1px solid #ddd;
			}

			#current-slide .label,
			#upcoming-slide .label {
				position: absolute;
				top: 10px;
				left: 10px;
				font-weight: bold;
				font-size: 14px;
				z-index: 2;
				color: rgba( 255, 255, 255, 0.9 );
			}

			#current-slide {
				position: absolute;
				width: 65%;
				height: 100%;
				top: 0;
				left: 0;
				padding-right: 0;
			}

			#upcoming-slide {
				position: absolute;
				width: 35%;
				height: 40%;
				right: 0;
				top: 0;
			}

			#speaker-controls {
				position: absolute;
				top: 40%;
				right: 0;
				width: 35%;
				height: 60%;
				overflow: auto;

				font-size: 18px;
			}

				.speaker-controls-time.hidden,
				.speaker-controls-notes.hidden {
					display: none;
				}

				.speaker-controls-time .label,
				.speaker-controls-notes .label {
					text-transform: uppercase;
					font-weight: normal;
					font-size: 0.66em;
					color: #666;
					margin: 0;
				}

				.speaker-controls-time {
					border-bottom: 1px solid rgba( 200, 200, 200, 0.5 );
					margin-bottom: 10px;
					padding: 10px 16px;
					padding-bottom: 20px;
					cursor: pointer;
				}

				.speaker-controls-time .reset-button {
					opacity: 0;
					float: right;
					color: #666;
					text-decoration: none;
				}
				.speaker-controls-time:hover .reset-button {
					opacity: 1;
				}

				.speaker-controls-time .timer,
				.speaker-controls-time .clock {
					width: 50%;
					font-size: 1.9em;
				}

				.speaker-controls-time .timer {
					float: left;
				}

				.speaker-controls-time .clock {
					float: right;
					text-align: right;
				}

				.speaker-controls-time span.mute {
					color: #bbb;
				}

				.speaker-controls-notes {
					padding: 10px 16px;
				}

				.speaker-controls-notes .value {
					margin-top: 5px;
					line-height: 1.4;
					font-size: 1.2em;
				}

			.clear {
				clear: both;
			}

			@media screen and (max-width: 1080px) {
				#speaker-controls {
					font-size: 16px;
				}
			}

			@media screen and (max-width: 900px) {
				#speaker-controls {
					font-size: 14px;
				}
			}

			@media screen and (max-width: 800px) {
				#speaker-controls {
					font-size: 12px;
				}
			}

		</style>
	</head>

	<body>

		<div id="current-slide"></div>
		<div id="upcoming-slide"><span class="label">UPCOMING:</span></div>
		<div id="speaker-controls">
			<div class="speaker-controls-time">
				<h4 class="label">Time <span class="reset-button">Click to Reset</span></h4>
				<div class="clock">
					<span class="clock-value">0:00 AM</span>
				</div>
				<div class="timer">
					<span class="hours-value">00</span><span class="minutes-value">:00</span><span class="seconds-value">:00</span>
				</div>
				<div class="clear"></div>
			</div>

			<div class="speaker-controls-notes hidden">
				<h4 class="label">Notes</h4>
				<div class="value"></div>
			</div>
		</div>

		<script src="../../plugin/markdown/marked.js"></script>
		<script>

			(function() {

				var notes,
					notesValue,
					currentState,
					currentSlide,
					upcomingSlide,
					connected = false;

				window.addEventListener( 'message', function( event ) {

					var data = JSON.parse( event.data );

					// Messages sent by the notes plugin inside of the main window
					if( data && data.namespace === 'reveal-notes' ) {
						if( data.type === 'connect' ) {
							handleConnectMessage( data );
						}
						else if( data.type === 'state' ) {
							handleStateMessage( data );
						}
					}
					// Messages sent by the reveal.js inside of the current slide preview
					else if( data && data.namespace === 'reveal' ) {
						if( /ready/.test( data.eventName ) ) {
							// Send a message back to notify that the handshake is complete
							window.opener.postMessage( JSON.stringify({ namespace: 'reveal-notes', type: 'connected'} ), '*' );
						}
						else if( /slidechanged|fragmentshown|fragmenthidden|overviewshown|overviewhidden|paused|resumed/.test( data.eventName ) && currentState !== JSON.stringify( data.state ) ) {
							window.opener.postMessage( JSON.stringify({ method: 'setState', args: [ data.state ]} ), '*' );
						}
					}

				} );

				/**
				 * Called when the main window is trying to establish a
				 * connection.
				 */
				function handleConnectMessage( data ) {

					if( connected === false ) {
						connected = true;

						setupIframes( data );
						setupKeyboard();
						setupNotes();
						setupTimer();
					}

				}

				/**
				 * Called when the main window sends an updated state.
				 */
				function handleStateMessage( data ) {

					// Store the most recently set state to avoid circular loops
					// applying the same state
					currentState = JSON.stringify( data.state );

					// No need for updating the notes in case of fragment changes
					if ( data.notes ) {
						notes.classList.remove( 'hidden' );
						if( data.markdown ) {
							notesValue.innerHTML = marked( data.notes );
						}
						else {
							notesValue.innerHTML = data.notes;
						}
					}
					else {
						notes.classList.add( 'hidden' );
					}

					// Update the note slides
					currentSlide.contentWindow.postMessage( JSON.stringify({ method: 'setState', args: [ data.state ] }), '*' );
					upcomingSlide.contentWindow.postMessage( JSON.stringify({ method: 'setState', args: [ data.state ] }), '*' );
					upcomingSlide.contentWindow.postMessage( JSON.stringify({ method: 'next' }), '*' );

				}

				// Limit to max one state update per X ms
				handleStateMessage = debounce( handleStateMessage, 200 );

				/**
				 * Forward keyboard events to the current slide window.
				 * This enables keyboard events to work even if focus
				 * isn't set on the current slide iframe.
				 */
				function setupKeyboard() {

					document.addEventListener( 'keydown', function( event ) {
						currentSlide.contentWindow.postMessage( JSON.stringify({ method: 'triggerKey', args: [ event.keyCode ] }), '*' );
					} );

				}

				/**
				 * Creates the preview iframes.
				 */
				function setupIframes( data ) {

					var params = [
						'receiver',
						'progress=false',
						'history=false',
						'transition=none',
						'autoSlide=0',
						'backgroundTransition=none'
					].join( '&' );

					var hash = '#/' + data.state.indexh + '/' + data.state.indexv;
					var currentURL = data.url + '?' + params + '&postMessageEvents=true' + hash;
					var upcomingURL = data.url + '?' + params + '&controls=false' + hash;

					currentSlide = document.createElement( 'iframe' );
					currentSlide.setAttribute( 'width', 1280 );
					currentSlide.setAttribute( 'height', 1024 );
					currentSlide.setAttribute( 'src', currentURL );
					document.querySelector( '#current-slide' ).appendChild( currentSlide );

					upcomingSlide = document.createElement( 'iframe' );
					upcomingSlide.setAttribute( 'width', 640 );
					upcomingSlide.setAttribute( 'height', 512 );
					upcomingSlide.setAttribute( 'src', upcomingURL );
					document.querySelector( '#upcoming-slide' ).appendChild( upcomingSlide );

				}

				/**
				 * Setup the notes UI.
				 */
				function setupNotes() {

					notes = document.querySelector( '.speaker-controls-notes' );
					notesValue = document.querySelector( '.speaker-controls-notes .value' );

				}

				/**
				 * Create the timer and clock and start updating them
				 * at an interval.
				 */
				function setupTimer() {

					var start = new Date(),
						timeEl = document.querySelector( '.speaker-controls-time' ),
						clockEl = timeEl.querySelector( '.clock-value' ),
						hoursEl = timeEl.querySelector( '.hours-value' ),
						minutesEl = timeEl.querySelector( '.minutes-value' ),
						secondsEl = timeEl.querySelector( '.seconds-value' );

					function _updateTimer() {

						var diff, hours, minutes, seconds,
							now = new Date();

						diff = now.getTime() - start.getTime();
						hours = Math.floor( diff / ( 1000 * 60 * 60 ) );
						minutes = Math.floor( ( diff / ( 1000 * 60 ) ) % 60 );
						seconds = Math.floor( ( diff / 1000 ) % 60 );

						clockEl.innerHTML = now.toLocaleTimeString( 'en-US', { hour12: true, hour: '2-digit', minute:'2-digit' } );
						hoursEl.innerHTML = zeroPadInteger( hours );
						hoursEl.className = hours > 0 ? '' : 'mute';
						minutesEl.innerHTML = ':' + zeroPadInteger( minutes );
						minutesEl.className = minutes > 0 ? '' : 'mute';
						secondsEl.innerHTML = ':' + zeroPadInteger( seconds );

					}

					// Update once directly
					_updateTimer();

					// Then update every second
					setInterval( _updateTimer, 1000 );

					timeEl.addEventListener( 'click', function() {
						start = new Date();
						_updateTimer();
						return false;
					} );

				}

				function zeroPadInteger( num ) {

					var str = '00' + parseInt( num );
					return str.substring( str.length - 2 );

				}

				/**
				 * Limits the frequency at which a function can be called.
				 */
				function debounce( fn, ms ) {

					var lastTime = 0,
						timeout;

					return function() {

						var args = arguments;
						var context = this;

						clearTimeout( timeout );

						var timeSinceLastCall = Date.now() - lastTime;
						if( timeSinceLastCall > ms ) {
							fn.apply( context, args );
							lastTime = Date.now();
						}
						else {
							timeout = setTimeout( function() {
								fn.apply( context, args );
								lastTime = Date.now();
							}, ms - timeSinceLastCall );
						}

					}

				}

			})();

		</script>
	</body>
</html>