| 1 | import speakerViewHTML from './speaker-view.html?raw' |
| 2 | |
| 3 | import { marked } from 'marked'; |
| 4 | |
| 5 | /** |
| 6 | * Handles opening of and synchronization with the reveal.js |
| 7 | * notes window. |
| 8 | * |
| 9 | * Handshake process: |
| 10 | * 1. This window posts 'connect' to notes window |
| 11 | * - Includes URL of presentation to show |
| 12 | * 2. Notes window responds with 'connected' when it is available |
| 13 | * 3. This window proceeds to send the current presentation state |
| 14 | * to the notes window |
| 15 | */ |
| 16 | const Plugin = () => { |
| 17 | |
| 18 | let connectInterval; |
| 19 | let speakerWindow = null; |
| 20 | let deck; |
| 21 | |
| 22 | /** |
| 23 | * Opens a new speaker view window. |
| 24 | */ |
| 25 | function openSpeakerWindow() { |
| 26 | |
| 27 | // If a window is already open, focus it |
| 28 | if( speakerWindow && !speakerWindow.closed ) { |
| 29 | speakerWindow.focus(); |
| 30 | } |
| 31 | else { |
| 32 | speakerWindow = window.open( 'about:blank', 'reveal.js - Notes', 'width=1100,height=700' ); |
| 33 | speakerWindow.marked = marked; |
| 34 | speakerWindow.document.write( speakerViewHTML ); |
| 35 | |
| 36 | if( !speakerWindow ) { |
| 37 | alert( 'Speaker view popup failed to open. Please make sure popups are allowed and reopen the speaker view.' ); |
| 38 | return; |
| 39 | } |
| 40 | |
| 41 | connect(); |
| 42 | } |
| 43 | |
| 44 | } |
| 45 | |
| 46 | /** |
| 47 | * Reconnect with an existing speaker view window. |
| 48 | */ |
| 49 | function reconnectSpeakerWindow( reconnectWindow ) { |
| 50 | |
| 51 | if( speakerWindow && !speakerWindow.closed ) { |
| 52 | speakerWindow.focus(); |
| 53 | } |
| 54 | else { |
| 55 | speakerWindow = reconnectWindow; |
| 56 | window.addEventListener( 'message', onPostMessage ); |
| 57 | onConnected(); |
| 58 | } |
| 59 | |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Connect to the notes window through a postmessage handshake. |
| 64 | * Using postmessage enables us to work in situations where the |
| 65 | * origins differ, such as a presentation being opened from the |
| 66 | * file system. |
| 67 | */ |
| 68 | function connect() { |
| 69 | |
| 70 | const presentationURL = deck.getConfig().url; |
| 71 | |
| 72 | const url = typeof presentationURL === 'string' ? presentationURL : |
| 73 | window.location.protocol + '//' + window.location.host + window.location.pathname + window.location.search; |
| 74 | |
| 75 | // Keep trying to connect until we get a 'connected' message back |
| 76 | connectInterval = setInterval( function() { |
| 77 | speakerWindow.postMessage( JSON.stringify( { |
| 78 | namespace: 'reveal-notes', |
| 79 | type: 'connect', |
| 80 | state: deck.getState(), |
| 81 | url |
| 82 | } ), '*' ); |
| 83 | }, 500 ); |
| 84 | |
| 85 | window.addEventListener( 'message', onPostMessage ); |
| 86 | |
| 87 | } |
| 88 | |
| 89 | /** |
| 90 | * Calls the specified Reveal.js method with the provided argument |
| 91 | * and then pushes the result to the notes frame. |
| 92 | */ |
| 93 | function callRevealApi( methodName, methodArguments, callId ) { |
| 94 | |
| 95 | let result = deck[methodName].apply( deck, methodArguments ); |
| 96 | speakerWindow.postMessage( JSON.stringify( { |
| 97 | namespace: 'reveal-notes', |
| 98 | type: 'return', |
| 99 | result, |
| 100 | callId |
| 101 | } ), '*' ); |
| 102 | |
| 103 | } |
| 104 | |
| 105 | /** |
| 106 | * Posts the current slide data to the notes window. |
| 107 | */ |
| 108 | function post( event ) { |
| 109 | |
| 110 | let slideElement = deck.getCurrentSlide(), |
| 111 | notesElements = slideElement.querySelectorAll( 'aside.notes' ), |
| 112 | fragmentElement = slideElement.querySelector( '.current-fragment' ); |
| 113 | |
| 114 | let messageData = { |
| 115 | namespace: 'reveal-notes', |
| 116 | type: 'state', |
| 117 | notes: '', |
| 118 | markdown: false, |
| 119 | whitespace: 'normal', |
| 120 | state: deck.getState() |
| 121 | }; |
| 122 | |
| 123 | // Look for notes defined in a slide attribute |
| 124 | if( slideElement.hasAttribute( 'data-notes' ) ) { |
| 125 | messageData.notes = slideElement.getAttribute( 'data-notes' ); |
| 126 | messageData.whitespace = 'pre-wrap'; |
| 127 | } |
| 128 | |
| 129 | // Look for notes defined in a fragment |
| 130 | if( fragmentElement ) { |
| 131 | let fragmentNotes = fragmentElement.querySelector( 'aside.notes' ); |
| 132 | if( fragmentNotes ) { |
| 133 | messageData.notes = fragmentNotes.innerHTML; |
| 134 | messageData.markdown = typeof fragmentNotes.getAttribute( 'data-markdown' ) === 'string'; |
| 135 | |
| 136 | // Ignore other slide notes |
| 137 | notesElements = null; |
| 138 | } |
| 139 | else if( fragmentElement.hasAttribute( 'data-notes' ) ) { |
| 140 | messageData.notes = fragmentElement.getAttribute( 'data-notes' ); |
| 141 | messageData.whitespace = 'pre-wrap'; |
| 142 | |
| 143 | // In case there are slide notes |
| 144 | notesElements = null; |
| 145 | } |
| 146 | } |
| 147 | |
| 148 | // Look for notes defined in an aside element |
| 149 | if( notesElements && notesElements.length ) { |
| 150 | // Ignore notes inside of fragments since those are shown |
| 151 | // individually when stepping through fragments |
| 152 | notesElements = Array.from( notesElements ).filter( notesElement => notesElement.closest( '.fragment' ) === null ); |
| 153 | |
| 154 | messageData.notes = notesElements.map( notesElement => notesElement.innerHTML ).join( '\n' ); |
| 155 | messageData.markdown = notesElements[0] && typeof notesElements[0].getAttribute( 'data-markdown' ) === 'string'; |
| 156 | } |
| 157 | |
| 158 | speakerWindow.postMessage( JSON.stringify( messageData ), '*' ); |
| 159 | |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * Check if the given event is from the same origin as the |
| 164 | * current window. |
| 165 | */ |
| 166 | function isSameOriginEvent( event ) { |
| 167 | |
| 168 | try { |
| 169 | return window.location.origin === event.source.location.origin; |
| 170 | } |
| 171 | catch ( error ) { |
| 172 | return false; |
| 173 | } |
| 174 | |
| 175 | } |
| 176 | |
| 177 | function onPostMessage( event ) { |
| 178 | |
| 179 | // Only allow same-origin messages |
| 180 | // (added 12/5/22 as a XSS safeguard) |
| 181 | if( isSameOriginEvent( event ) ) { |
| 182 | |
| 183 | try { |
| 184 | let data = JSON.parse( event.data ); |
| 185 | if( data && data.namespace === 'reveal-notes' && data.type === 'connected' ) { |
| 186 | clearInterval( connectInterval ); |
| 187 | onConnected(); |
| 188 | } |
| 189 | else if( data && data.namespace === 'reveal-notes' && data.type === 'call' ) { |
| 190 | callRevealApi( data.methodName, data.arguments, data.callId ); |
| 191 | } |
| 192 | } catch (e) {} |
| 193 | |
| 194 | } |
| 195 | |
| 196 | } |
| 197 | |
| 198 | /** |
| 199 | * Called once we have established a connection to the notes |
| 200 | * window. |
| 201 | */ |
| 202 | function onConnected() { |
| 203 | |
| 204 | // Monitor events that trigger a change in state |
| 205 | deck.on( 'slidechanged', post ); |
| 206 | deck.on( 'fragmentshown', post ); |
| 207 | deck.on( 'fragmenthidden', post ); |
| 208 | deck.on( 'overviewhidden', post ); |
| 209 | deck.on( 'overviewshown', post ); |
| 210 | deck.on( 'paused', post ); |
| 211 | deck.on( 'resumed', post ); |
| 212 | deck.on( 'previewiframe', post ); |
| 213 | deck.on( 'previewimage', post ); |
| 214 | deck.on( 'previewvideo', post ); |
| 215 | deck.on( 'closeoverlay', post ); |
| 216 | |
| 217 | // Post the initial state |
| 218 | post(); |
| 219 | |
| 220 | } |
| 221 | |
| 222 | return { |
| 223 | id: 'notes', |
| 224 | |
| 225 | init: function( reveal ) { |
| 226 | |
| 227 | deck = reveal; |
| 228 | |
| 229 | if( !/receiver/i.test( window.location.search ) ) { |
| 230 | |
| 231 | // If the there's a 'notes' query set, open directly |
| 232 | if( window.location.search.match( /(\?|\&)notes/gi ) !== null ) { |
| 233 | openSpeakerWindow(); |
| 234 | } |
| 235 | else { |
| 236 | // Keep listening for speaker view heartbeats. If we receive a |
| 237 | // heartbeat from an orphaned window, reconnect it. This ensures |
| 238 | // that we remain connected to the notes even if the presentation |
| 239 | // is reloaded. |
| 240 | window.addEventListener( 'message', event => { |
| 241 | |
| 242 | if( !speakerWindow && typeof event.data === 'string' ) { |
| 243 | let data; |
| 244 | |
| 245 | try { |
| 246 | data = JSON.parse( event.data ); |
| 247 | } |
| 248 | catch( error ) {} |
| 249 | |
| 250 | if( data && data.namespace === 'reveal-notes' && data.type === 'heartbeat' ) { |
| 251 | reconnectSpeakerWindow( event.source ); |
| 252 | } |
| 253 | } |
| 254 | }); |
| 255 | } |
| 256 | |
| 257 | // Open the notes when the 's' key is hit |
| 258 | deck.addKeyBinding({keyCode: 83, key: 'S', description: 'Speaker notes view'}, function() { |
| 259 | openSpeakerWindow(); |
| 260 | } ); |
| 261 | |
| 262 | } |
| 263 | |
| 264 | }, |
| 265 | |
| 266 | open: openSpeakerWindow |
| 267 | }; |
| 268 | |
| 269 | }; |
| 270 | |
| 271 | export default Plugin; |
| 272 |