( function( window, $, undefined ) {

	'use strict';

	var $window = $( window ),

		$document = $( document ),

		$adminBar = $( '#wpadminbar' ),

		$footer = $( '#wpfooter' );

	/* Autoresize editor. */

	$( function() {

		var $wrap = $( '#postdivrich' ),

			$contentWrap = $( '#wp-content-wrap' ),

			$tools = $( '#wp-content-editor-tools' ),

			$visualTop = $(),

			$visualEditor = $(),

			$textTop = $( '#ed_toolbar' ),

			$textEditor = $( '#content' ),

			$textEditorClone = $( '<div id="content-textarea-clone" class="wp-exclude-emoji"></div>' ),

			$bottom = $( '#post-status-info' ),

			$menuBar = $(),

			$statusBar = $(),

			$sideSortables = $( '#side-sortables' ),

			$postboxContainer = $( '#postbox-container-1' ),

			$postBody = $('#post-body'),

			fullscreen = window.wp.editor && window.wp.editor.fullscreen,

			mceEditor,

			mceBind = function(){},

			mceUnbind = function(){},

			fixedTop = false,

			fixedBottom = false,

			fixedSideTop = false,

			fixedSideBottom = false,

			scrollTimer,

			lastScrollPosition = 0,

			pageYOffsetAtTop = 130,

			pinnedToolsTop = 56,

			sidebarBottom = 20,

			autoresizeMinHeight = 300,

			initialMode = $contentWrap.hasClass( 'tmce-active' ) ? 'tinymce' : 'html',

			advanced = !! parseInt( window.getUserSetting( 'hidetb' ), 10 ),

			// These are corrected when adjust() runs, except on scrolling if already set.

			heights = {

				windowHeight: 0,

				windowWidth: 0,

				adminBarHeight: 0,

				toolsHeight: 0,

				menuBarHeight: 0,

				visualTopHeight: 0,

				textTopHeight: 0,

				bottomHeight: 0,

				statusBarHeight: 0,

				sideSortablesHeight: 0

			};

		$textEditorClone.insertAfter( $textEditor );

		$textEditorClone.css( {

			'font-family': $textEditor.css( 'font-family' ),

			'font-size': $textEditor.css( 'font-size' ),

			'line-height': $textEditor.css( 'line-height' ),

			'white-space': 'pre-wrap',

			'word-wrap': 'break-word'

		} );

		function getHeights() {

			var windowWidth = $window.width();

			heights = {

				windowHeight: $window.height(),

				windowWidth: windowWidth,

				adminBarHeight: ( windowWidth > 600 ? $adminBar.outerHeight() : 0 ),

				toolsHeight: $tools.outerHeight() || 0,

				menuBarHeight: $menuBar.outerHeight() || 0,

				visualTopHeight: $visualTop.outerHeight() || 0,

				textTopHeight: $textTop.outerHeight() || 0,

				bottomHeight: $bottom.outerHeight() || 0,

				statusBarHeight: $statusBar.outerHeight() || 0,

				sideSortablesHeight: $sideSortables.height() || 0

			};

			// Adjust for hidden

			if ( heights.menuBarHeight < 3 ) {

				heights.menuBarHeight = 0;

			}

		}

		function textEditorKeyup( event ) {

			var VK = jQuery.ui.keyCode,

				key = event.keyCode,

				range = document.createRange(),

				selStart = $textEditor[0].selectionStart,

				selEnd = $textEditor[0].selectionEnd,

				textNode = $textEditorClone[0].firstChild,

				buffer = 10,

				offset, cursorTop, cursorBottom, editorTop, editorBottom;

			if ( selStart && selEnd && selStart !== selEnd ) {

				return;

			}

			// These are not TinyMCE ranges.

			try {

				range.setStart( textNode, selStart );

				range.setEnd( textNode, selEnd + 1 );

			} catch ( ex ) {}

			offset = range.getBoundingClientRect();

			if ( ! offset.height ) {

				return;

			}

			cursorTop = offset.top - buffer;

			cursorBottom = cursorTop + offset.height + buffer;

			editorTop = heights.adminBarHeight + heights.toolsHeight + heights.textTopHeight;

			editorBottom = heights.windowHeight - heights.bottomHeight;

			if ( cursorTop < editorTop && ( key === VK.UP || key === VK.LEFT || key === VK.BACKSPACE ) ) {

				window.scrollTo( window.pageXOffset, cursorTop + window.pageYOffset - editorTop );

			} else if ( cursorBottom > editorBottom ) {

				window.scrollTo( window.pageXOffset, cursorBottom + window.pageYOffset - editorBottom );

			}

		}

		function textEditorResize() {

			if ( ( mceEditor && ! mceEditor.isHidden() ) || ( ! mceEditor && initialMode === 'tinymce' ) ) {

				return;

			}

			var textEditorHeight = $textEditor.height(),

				hiddenHeight;

			$textEditorClone.width( $textEditor.width() - 22 );

			$textEditorClone.text( $textEditor.val() + ' ' );

			hiddenHeight = $textEditorClone.height();

			if ( hiddenHeight < autoresizeMinHeight ) {

				hiddenHeight = autoresizeMinHeight;

			}

			if ( hiddenHeight === textEditorHeight ) {

				return;

			}

			$textEditor.height( hiddenHeight );

			adjust();

		}

		// We need to wait for TinyMCE to initialize.

		$document.on( 'tinymce-editor-init.editor-expand', function( event, editor ) {

			var VK = window.tinymce.util.VK,

				hideFloatPanels = _.debounce( function() {

					! $( '.mce-floatpanel:hover' ).length && window.tinymce.ui.FloatPanel.hideAll();

					$( '.mce-tooltip' ).hide();

				}, 1000, true );

			// Make sure it's the main editor.

			if ( editor.id !== 'content' ) {

				return;

			}

			// Copy the editor instance.

			mceEditor = editor;

			// Set the minimum height to the initial viewport height.

			editor.settings.autoresize_min_height = autoresizeMinHeight;

			// Get the necessary UI elements.

			$visualTop = $contentWrap.find( '.mce-toolbar-grp' );

			$visualEditor = $contentWrap.find( '.mce-edit-area' );

			$statusBar = $contentWrap.find( '.mce-statusbar' );

			$menuBar = $contentWrap.find( '.mce-menubar' );

			function mceGetCursorOffset() {

				var node = editor.selection.getNode(),

					range, view, offset;

				if ( editor.wp && editor.wp.getView && ( view = editor.wp.getView( node ) ) ) {

					offset = view.getBoundingClientRect();

				} else {

					range = editor.selection.getRng();

					try {

						offset = range.getClientRects()[0];

					} catch( er ) {}

					if ( ! offset ) {

						offset = node.getBoundingClientRect();

					}

				}

				return offset.height ? offset : false;

			}

			// Make sure the cursor is always visible.

			// This is not only necessary to keep the cursor between the toolbars,

			// but also to scroll the window when the cursor moves out of the viewport to a wpview.

			// Setting a buffer > 0 will prevent the browser default.

			// Some browsers will scroll to the middle,

			// others to the top/bottom of the *window* when moving the cursor out of the viewport.

			function mceKeyup( event ) {

				var key = event.keyCode;

				// Bail on special keys.

				if ( key <= 47 && ! ( key === VK.SPACEBAR || key === VK.ENTER || key === VK.DELETE || key === VK.BACKSPACE || key === VK.UP || key === VK.LEFT || key === VK.DOWN || key === VK.UP ) ) {

					return;

				// OS keys, function keys, num lock, scroll lock

				} else if ( ( key >= 91 && key <= 93 ) || ( key >= 112 && key <= 123 ) || key === 144 || key === 145 ) {

					return;

				}

				mceScroll( key );

			}

			function mceScroll( key ) {

				var offset = mceGetCursorOffset(),

					buffer = 50,

					cursorTop, cursorBottom, editorTop, editorBottom;

				if ( ! offset ) {

					return;

				}

				cursorTop = offset.top + editor.iframeElement.getBoundingClientRect().top;

				cursorBottom = cursorTop + offset.height;

				cursorTop = cursorTop - buffer;

				cursorBottom = cursorBottom + buffer;

				editorTop = heights.adminBarHeight + heights.toolsHeight + heights.menuBarHeight + heights.visualTopHeight;

				editorBottom = heights.windowHeight - ( advanced ? heights.bottomHeight + heights.statusBarHeight : 0 );

				// Don't scroll if the node is taller than the visible part of the editor

				if ( editorBottom - editorTop < offset.height ) {

					return;

				}

				if ( cursorTop < editorTop && ( key === VK.UP || key === VK.LEFT || key === VK.BACKSPACE ) ) {

					window.scrollTo( window.pageXOffset, cursorTop + window.pageYOffset - editorTop );

				} else if ( cursorBottom > editorBottom ) {

					window.scrollTo( window.pageXOffset, cursorBottom + window.pageYOffset - editorBottom );

				}

			}

			function mceFullscreenToggled( event ) {

				if ( ! event.state ) {

					adjust();

				}

			}

			// Adjust when switching editor modes.

			function mceShow() {

				$window.on( 'scroll.mce-float-panels', hideFloatPanels );

				setTimeout( function() {

					editor.execCommand( 'wpAutoResize' );

					adjust();

				}, 300 );

			}

			function mceHide() {

				$window.off( 'scroll.mce-float-panels' );

				setTimeout( function() {

					var top = $contentWrap.offset().top;

					if ( window.pageYOffset > top ) {

						window.scrollTo( window.pageXOffset, top - heights.adminBarHeight );

					}

					textEditorResize();

					adjust();

				}, 100 );

				adjust();

			}

			function toggleAdvanced() {

				advanced = ! advanced;

			}

			mceBind = function() {

				editor.on( 'keyup', mceKeyup );

				editor.on( 'show', mceShow );

				editor.on( 'hide', mceHide );

				editor.on( 'wp-toolbar-toggle', toggleAdvanced );

				// Adjust when the editor resizes.

				editor.on( 'setcontent wp-autoresize wp-toolbar-toggle', adjust );

				// Don't hide the caret after undo/redo.

				editor.on( 'undo redo', mceScroll );

				// Adjust when exiting TinyMCE's fullscreen mode.

				editor.on( 'FullscreenStateChanged', mceFullscreenToggled );

				$window.off( 'scroll.mce-float-panels' ).on( 'scroll.mce-float-panels', hideFloatPanels );

			};

			mceUnbind = function() {

				editor.off( 'keyup', mceKeyup );

				editor.off( 'show', mceShow );

				editor.off( 'hide', mceHide );

				editor.off( 'wp-toolbar-toggle', toggleAdvanced );

				editor.off( 'setcontent wp-autoresize wp-toolbar-toggle', adjust );

				editor.off( 'undo redo', mceScroll );

				editor.off( 'FullscreenStateChanged', mceFullscreenToggled );

				$window.off( 'scroll.mce-float-panels' );

			};

			if ( $wrap.hasClass( 'wp-editor-expand' ) ) {

				// Adjust "immediately"

				mceBind();

				initialResize( adjust );

			}

		} );

		// Adjust the toolbars based on the active editor mode.

		function adjust( event ) {

			// Make sure we're not in fullscreen mode.

			if ( fullscreen && fullscreen.settings.visible ) {

				return;

			}

			var windowPos = $window.scrollTop(),

				type = event && event.type,

				resize = type !== 'scroll',

				visual = mceEditor && ! mceEditor.isHidden(),

				buffer = autoresizeMinHeight,

				postBodyTop = $postBody.offset().top,

				borderWidth = 1,

				contentWrapWidth = $contentWrap.width(),

				$top, $editor, sidebarTop, footerTop, canPin,

				topPos, topHeight, editorPos, editorHeight;

			// Refresh the heights

			if ( resize || ! heights.windowHeight ) {

				getHeights();

			}

			if ( ! visual && type === 'resize' ) {

				textEditorResize();

			}

			if ( visual ) {

				$top = $visualTop;

				$editor = $visualEditor;

				topHeight = heights.visualTopHeight;

			} else {