/**
 * @output wp-admin/js/common.js
 */

/* global setUserSetting, ajaxurl, commonL10n, alert, confirm, pagenow */
/* global columns, screenMeta */

/**
 *  Adds common WordPress functionality to the window.
 *
 *  @param {jQuery} $        jQuery object.
 *  @param {Object} window   The window object.
 *  @param {mixed} undefined Unused.
 */
( function( $, window, undefined ) {
	var $document = $( document ),
		$window = $( window ),
		$body = $( document.body );

/**
 * Removed in 3.3.0, needed for back-compatibility.
 *
 * @since 2.7.0
 * @deprecated 3.3.0
 */
window.adminMenu = {
	init : function() {},
	fold : function() {},
	restoreMenuState : function() {},
	toggle : function() {},
	favorites : function() {}
};

// Show/hide/save table columns.
window.columns = {

	/**
	 * Initializes the column toggles in the screen options.
	 *
	 * Binds an onClick event to the checkboxes to show or hide the table columns
	 * based on their toggled state. And persists the toggled state.
	 *
	 * @since 2.7.0
	 *
	 * @returns {void}
	 */
	init : function() {
		var that = this;
		$('.hide-column-tog', '#adv-settings').click( function() {
			var $t = $(this), column = $t.val();
			if ( $t.prop('checked') )
				that.checked(column);
			else
				that.unchecked(column);

			columns.saveManageColumnsState();
		});
	},

	/**
	 * Saves the toggled state for the columns.
	 *
	 * Saves whether the columns should be shown or hidden on a page.
	 *
	 * @since 3.0.0
	 *
	 * @returns {void}
	 */
	saveManageColumnsState : function() {
		var hidden = this.hidden();
		$.post(ajaxurl, {
			action: 'hidden-columns',
			hidden: hidden,
			screenoptionnonce: $('#screenoptionnonce').val(),
			page: pagenow
		});
	},

	/**
	 * Makes a column visible and adjusts the column span for the table.
	 *
	 * @since 3.0.0
	 * @param {string} column The column name.
	 *
	 * @returns {void}
	 */
	checked : function(column) {
		$('.column-' + column).removeClass( 'hidden' );
		this.colSpanChange(+1);
	},

	/**
	 * Hides a column and adjusts the column span for the table.
	 *
	 * @since 3.0.0
	 * @param {string} column The column name.
	 *
	 * @returns {void}
	 */
	unchecked : function(column) {
		$('.column-' + column).addClass( 'hidden' );
		this.colSpanChange(-1);
	},

	/**
	 * Gets all hidden columns.
	 *
	 * @since 3.0.0
	 *
	 * @returns {string} The hidden column names separated by a comma.
	 */
	hidden : function() {
		return $( '.manage-column[id]' ).filter( '.hidden' ).map(function() {
			return this.id;
		}).get().join( ',' );
	},

	/**
	 * Gets the checked column toggles from the screen options.
	 *
	 * @since 3.0.0
	 *
	 * @returns {string} String containing the checked column names.
	 */
	useCheckboxesForHidden : function() {
		this.hidden = function(){
			return $('.hide-column-tog').not(':checked').map(function() {
				var id = this.id;
				return id.substring( id, id.length - 5 );
			}).get().join(',');
		};
	},

	/**
	 * Adjusts the column span for the table.
	 *
	 * @since 3.1.0
	 *
	 * @param {int} diff The modifier for the column span.
	 */
	colSpanChange : function(diff) {
		var $t = $('table').find('.colspanchange'), n;
		if ( !$t.length )
			return;
		n = parseInt( $t.attr('colspan'), 10 ) + diff;
		$t.attr('colspan', n.toString());
	}
};

$document.ready(function(){columns.init();});

/**
 * Validates that the required form fields are not empty.
 *
 * @since 2.9.0
 *
 * @param {jQuery} form The form to validate.
 *
 * @returns {boolean} Returns true if all required fields are not an empty string.
 */
window.validateForm = function( form ) {
	return !$( form )
		.find( '.form-required' )
		.filter( function() { return $( ':input:visible', this ).val() === ''; } )
		.addClass( 'form-invalid' )
		.find( ':input:visible' )
		.change( function() { $( this ).closest( '.form-invalid' ).removeClass( 'form-invalid' ); } )
		.length;
};

// stub for doing better warnings
/**
 * Shows message pop-up notice or confirmation message.
 *
 * @since 2.7.0
 *
 * @type {{warn: showNotice.warn, note: showNotice.note}}
 *
 * @returns {void}
 */
window.showNotice = {

	/**
	 * Shows a delete confirmation pop-up message.
	 *
	 * @since 2.7.0
	 *
	 * @returns {boolean} Returns true if the message is confirmed.
	 */
	warn : function() {
		var msg = commonL10n.warnDelete || '';
		if ( confirm(msg) ) {
			return true;
		}

		return false;
	},

	/**
	 * Shows an alert message.
	 *
	 * @since 2.7.0
	 *
	 * @param text The text to display in the message.
	 */
	note : function(text) {
		alert(text);
	}
};

/**
 * Represents the functions for the meta screen options panel.
 *
 * @since 3.2.0
 *
 * @type {{element: null, toggles: null, page: null, init: screenMeta.init,
 *         toggleEvent: screenMeta.toggleEvent, open: screenMeta.open,
 *         close: screenMeta.close}}
 *
 * @returns {void}
 */
window.screenMeta = {
	element: null, // #screen-meta
	toggles: null, // .screen-meta-toggle
	page:    null, // #wpcontent

	/**
	 * Initializes the screen meta options panel.
	 *
	 * @since 3.2.0
	 *
	 * @returns {void}
	 */
	init: function() {
		this.element = $('#screen-meta');
		this.toggles = $( '#screen-meta-links' ).find( '.show-settings' );
		this.page    = $('#wpcontent');

		this.toggles.click( this.toggleEvent );
	},

	/**
	 * Toggles the screen meta options panel.
	 *
	 * @since 3.2.0
	 *
	 * @returns {void}
	 */
	toggleEvent: function() {
		var panel = $( '#' + $( this ).attr( 'aria-controls' ) );

		if ( !panel.length )
			return;

		if ( panel.is(':visible') )
			screenMeta.close( panel, $(this) );
		else
			screenMeta.open( panel, $(this) );
	},

	/**
	 * Opens the screen meta options panel.
	 *
	 * @since 3.2.0
	 *
	 * @param {jQuery} panel  The screen meta options panel div.
	 * @param {jQuery} button The toggle button.
	 *
	 * @returns {void}
	 */
	open: function( panel, button ) {

		$( '#screen-meta-links' ).find( '.screen-meta-toggle' ).not( button.parent() ).css( 'visibility', 'hidden' );

		panel.parent().show();

		/**
		 * Sets the focus to the meta options panel and adds the necessary CSS classes.
		 *
		 * @since 3.2.0
		 *
		 * @returns {void}
		 */
		panel.slideDown( 'fast', function() {
			panel.focus();
			button.addClass( 'screen-meta-active' ).attr( 'aria-expanded', true );
		});

		$document.trigger( 'screen:options:open' );
	},

	/**
	 * Closes the screen meta options panel.
	 *
	 * @since 3.2.0
	 *
	 * @param {jQuery} panel  The screen meta options panel div.
	 * @param {jQuery} button The toggle button.
	 *
	 * @returns {void}
	 */
	close: function( panel, button ) {
		/**
		 * Hides the screen meta options panel.
		 *
		 * @since 3.2.0
		 *
		 * @returns {void}
		 */
		panel.slideUp( 'fast', function() {
			button.removeClass( 'screen-meta-active' ).attr( 'aria-expanded', false );
			$('.screen-meta-toggle').css('visibility', '');
			panel.parent().hide();
		});

		$document.trigger( 'screen:options:close' );
	}
};

/**
 * Initializes the help tabs in the help panel.
 *
 * @param {Event} e The event object.
 *
 * @returns {void}
 */
$('.contextual-help-tabs').delegate('a', 'click', function(e) {
	var link = $(this),
		panel;

	e.preventDefault();

	// Don't do anything if the click is for the tab already showing.
	if ( link.is('.active a') )
		return false;

	// Links
	$('.contextual-help-tabs .active').removeClass('active');
	link.parent('li').addClass('active');

	panel = $( link.attr('href') );

	// Panels
	$('.help-tab-content').not( panel ).removeClass('active').hide();
	panel.addClass('active').show();
});

/**
 * Update custom permalink structure via buttons.
 */
var permalinkStructureFocused = false,
    $permalinkStructure       = $( '#permalink_structure' ),
    $permalinkStructureInputs = $( '.permalink-structure input:radio' ),
    $permalinkCustomSelection = $( '#custom_selection' ),
    $availableStructureTags   = $( '.form-table.permalink-structure .available-structure-tags button' );

// Change permalink structure input when selecting one of the common structures.
$permalinkStructureInputs.on( 'change', function() {
	if ( 'custom' === this.value ) {
		return;
	}

	$permalinkStructure.val( this.value );

	// Update button states after selection.
	$availableStructureTags.each( function() {
		changeStructureTagButtonState( $( this ) );
	} );
} );

$permalinkStructure.on( 'click input', function() {
	$permalinkCustomSelection.prop( 'checked', true );
} );

// Check if the permalink structure input field has had focus at least once.
$permalinkStructure.on( 'focus', function( event ) {
	permalinkStructureFocused = true;
	$( this ).off( event );
} );

/**
 * Enables or disables a structure tag button depending on its usage.
 *
 * If the structure is already used in the custom permalink structure,
 * it will be disabled.
 *
 * @param {object} button Button jQuery object.
 */
function changeStructureTagButtonState( button ) {
	if ( -1 !== $permalinkStructure.val().indexOf( button.text().trim() ) ) {
		button.attr( 'data-label', button.attr( 'aria-label' ) );
		button.attr( 'aria-label', button.attr( 'data-used' ) );
		button.attr( 'aria-pressed', true );
		button.addClass( 'active' );
	} else if ( button.attr( 'data-label' ) ) {
		button.attr( 'aria-label', button.attr( 'data-label' ) );
		button.attr( 'aria-pressed', false );
		button.removeClass( 'active' );
	}
}

// Check initial button state.
$availableStructureTags.each( function() {
	changeStructureTagButtonState( $( this ) );
} );

// Observe permalink structure field and disable buttons of tags that are already present.
$permalinkStructure.on( 'change', function() {
	$availableStructureTags.each( function() {
		changeStructureTagButtonState( $( this ) );
	} );
} );

$availableStructureTags.on( 'click', function() {
	var permalinkStructureValue = $permalinkStructure.val(),
	    selectionStart          = $permalinkStructure[ 0 ].selectionStart,
	    selectionEnd            = $permalinkStructure[ 0 ].selectionEnd,
	    textToAppend            = $( this ).text().trim(),
	    textToAnnounce          = $( this ).attr( 'data-added' ),
	    newSelectionStart;

	// Remove structure tag if already part of the structure.
	if ( -1 !== permalinkStructureValue.indexOf( textToAppend ) ) {
		permalinkStructureValue = permalinkStructureValue.replace( textToAppend + '/', '' );

		$permalinkStructure.val( '/' === permalinkStructureValue ? '' : permalinkStructureValue );

		// Announce change to screen readers.
		$( '#custom_selection_updated' ).text( textToAnnounce );

		// Disable button.
		changeStructureTagButtonState( $( this ) );

		return;
	}

	// Input field never had focus, move selection to end of input.
	if ( ! permalinkStructureFocused && 0 === selectionStart && 0 === selectionEnd ) {
		selectionStart = selectionEnd = permalinkStructureValue.length;
	}

	$permalinkCustomSelection.prop( 'checked', true );

	// Prepend and append slashes if necessary.
	if ( '/' !== permalinkStructureValue.substr( 0, selectionStart ).substr( -1 ) ) {
		textToAppend = '/' + textToAppend;
	}

	if ( '/' !== permalinkStructureValue.substr( selectionEnd, 1 ) ) {
		textToAppend = textToAppend + '/';
	}

	// Insert structure tag at the specified position.
	$permalinkStructure.val( permalinkStructureValue.substr( 0, selectionStart ) + textToAppend + permalinkStructureValue.substr( selectionEnd ) );

	// Announce change to screen readers.
	$( '#custom_selection_updated' ).text( textToAnnounce );

	// Disable button.
	changeStructureTagButtonState( $( this ) );

	// If input had focus give it back with cursor right after appended text.
	if ( permalinkStructureFocused && $permalinkStructure[0].setSelectionRange ) {
		newSelectionStart = ( permalinkStructureValue.substr( 0, selectionStart ) + textToAppend ).length;
		$permalinkStructure[0].setSelectionRange( newSelectionStart, newSelectionStart );
		$permalinkStructure.focus();
	}
} );

$document.ready( function() {
	var checks, first, last, checked, sliced, mobileEvent, transitionTimeout, focusedRowActions,
		lastClicked = false,
		pageInput = $('input.current-page'),
		currentPage = pageInput.val(),
		isIOS = /iPhone|iPad|iPod/.test( navigator.userAgent ),
		isAndroid = navigator.userAgent.indexOf( 'Android' ) !== -1,
		isIE8 = $( document.documentElement ).hasClass( 'ie8' ),
		$adminMenuWrap = $( '#adminmenuwrap' ),
		$wpwrap = $( '#wpwrap' ),
		$adminmenu = $( '#adminmenu' ),
		$overlay = $( '#wp-responsive-overlay' ),
		$toolbar = $( '#wp-toolbar' ),
		$toolbarPopups = $toolbar.find( 'a[aria-haspopup="true"]' ),
		$sortables = $('.meta-box-sortables'),
		wpResponsiveActive = false,
		$adminbar = $( '#wpadminbar' ),
		lastScrollPosition = 0,
		pinnedMenuTop = false,
		pinnedMenuBottom = false,
		menuTop = 0,
		menuState,
		menuIsPinned = false,
		height = {
			window: $window.height(),
			wpwrap: $wpwrap.height(),
			adminbar: $adminbar.height(),
			menu: $adminMenuWrap.height()
		},
		$headerEnd = $( '.wp-header-end' );

	/**
	 * Makes the fly-out submenu header clickable, when the menu is folded.
	 *
	 * @param {Event} e The event object.
	 *
	 * @returns {void}
	 */
	$adminmenu.on('click.wp-submenu-head', '.wp-submenu-head', function(e){
		$(e.target).parent().siblings('a').get(0).click();
	});

	/**
	 * Collapses the admin menu.
	 *
	 * @returns {void}
	 */
	$( '#collapse-button' ).on( 'click.collapse-menu', function() {
		var viewportWidth = getViewportWidth() || 961;

		// reset any compensation for submenus near the bottom of the screen
		$('#adminmenu div.wp-submenu').css('margin-top', '');

		if ( viewportWidth < 960 ) {
			if ( $body.hasClass('auto-fold') ) {
				$body.removeClass('auto-fold').removeClass('folded');
				setUserSetting('unfold', 1);
				setUserSetting('mfold', 'o');
				menuState = 'open';
			} else {
				$body.addClass('auto-fold');
				setUserSetting('unfold', 0);
				menuState = 'folded';
			}
		} else {
			if ( $body.hasClass('folded') ) {
				$body.removeClass('folded');
				setUserSetting('mfold', 'o');
				menuState = 'open';
			} else {
				$body.addClass('folded');
				setUserSetting('mfold', 'f');
				menuState = 'folded';
			}
		}

		$document.trigger( 'wp-collapse-menu', { state: menuState } );
	});

	/**
	 * Handles the `aria-haspopup` attribute on the current menu item when it has a submenu.
	 *
	 * @since 4.4.0
	 *
	 * @returns {void}
	 */
	function currentMenuItemHasPopup() {
		var $current = $( 'a.wp-has-current-submenu' );

		if ( 'folded' === menuState ) {
			// When folded or auto-folded and not responsive view, the current menu item does have a fly-out sub-menu.
			$current.attr( 'aria-haspopup', 'true' );
		} else {
			// When expanded or in responsive view, reset aria-haspopup.
			$current.attr( 'aria-haspopup', 'false' );
		}
	}

	$document.on( 'wp-menu-state-set wp-collapse-menu wp-responsive-activate wp-responsive-deactivate', currentMenuItemHasPopup );

	/**
	 * Ensures an admin submenu is within the visual viewport.
	 *
	 * @since 4.1.0
	 *
	 * @param {jQuery} $menuItem The parent menu item containing the submenu.
	 *
	 * @returns {void}
	 */
	function adjustSubmenu( $menuItem ) {
		var bottomOffset, pageHeight, adjustment, theFold, menutop, wintop, maxtop,
			$submenu = $menuItem.find( '.wp-submenu' );

		menutop = $menuItem.offset().top;
		wintop = $window.scrollTop();
		maxtop = menutop - wintop - 30; // max = make the top of the sub almost touch admin bar

		bottomOffset = menutop + $submenu.height() + 1; // Bottom offset of the menu
		pageHeight = $wpwrap.height(); // Height of the entire page
		adjustment = 60 + bottomOffset - pageHeight;
		theFold = $window.height() + wintop - 50; // The fold

		if ( theFold < ( bottomOffset - adjustment ) ) {
			adjustment = bottomOffset - theFold;
		}

		if ( adjustment > maxtop ) {
			adjustment = maxtop;
		}

		if ( adjustment > 1 ) {
			$submenu.css( 'margin-top', '-' + adjustment + 'px' );
		} else {
			$submenu.css( 'margin-top', '' );
		}
	}

	if ( 'ontouchstart' in window || /IEMobile\/[1-9]/.test(navigator.userAgent) ) { // touch screen device
		// iOS Safari works with touchstart, the rest work with click
		mobileEvent = isIOS ? 'touchstart' : 'click';

		/**
		 * Closes any open submenus when touch/click is not on the menu.
		 *
		 * @param {Event} e The event object.
		 *
		 * @returns {void}
		 */
		$body.on( mobileEvent+'.wp-mobile-hover', function(e) {
			if ( $adminmenu.data('wp-responsive') ) {
				return;
			}

			if ( ! $( e.target ).closest( '#adminmenu' ).length ) {
				$adminmenu.find( 'li.opensub' ).removeClass( 'opensub' );
			}
		});

		/**
		 * Handles the opening or closing the submenu based on the mobile click|touch event.
		 *
		 * @param {Event} event The event object.
		 *
		 * @returns {void}
		 */
		$adminmenu.find( 'a.wp-has-submenu' ).on( mobileEvent + '.wp-mobile-hover', function( event ) {
			var $menuItem = $(this).parent();

			if ( $adminmenu.data( 'wp-responsive' ) ) {
				return;
			}

			// Show the sub instead of following the link if:
			//	- the submenu is not open
			//	- the submenu is not shown inline or the menu is not folded
			if ( ! $menuItem.hasClass( 'opensub' ) && ( ! $menuItem.hasClass( 'wp-menu-open' ) || $menuItem.width() < 40 ) ) {
				event.preventDefault();
				adjustSubmenu( $menuItem );
				$adminmenu.find( 'li.opensub' ).removeClass( 'opensub' );
				$menuItem.addClass('opensub');
			}
		});
	}

	if ( ! isIOS && ! isAndroid ) {
		$adminmenu.find( 'li.wp-has-submenu' ).hoverIntent({

			/**
			 * Opens the submenu when hovered over the menu item for desktops.
			 *
			 * @returns {void}
			 */
			over: function() {
				var $menuItem = $( this ),
					$submenu = $menuItem.find( '.wp-submenu' ),
					top = parseInt( $submenu.css( 'top' ), 10 );

				if ( isNaN( top ) || top > -5 ) { // the submenu is visible
					return;
				}

				if ( $adminmenu.data( 'wp-responsive' ) ) {
					// The menu is in responsive mode, bail
					return;
				}

				adjustSubmenu( $menuItem );
				$adminmenu.find( 'li.opensub' ).removeClass( 'opensub' );
				$menuItem.addClass( 'opensub' );
			},

			/**
			 * Closes the submenu when no longer hovering the menu item.
			 *
			 * @returns {void}
			 */
			out: function(){
				if ( $adminmenu.data( 'wp-responsive' ) ) {
					// The menu is in responsive mode, bail
					return;
				}

				$( this ).removeClass( 'opensub' ).find( '.wp-submenu' ).css( 'margin-top', '' );
			},
			timeout: 200,
			sensitivity: 7,
			interval: 90
		});

		/**
		 * Opens the submenu on when focused on the menu item.
		 *
		 * @param {Event} event The event object.
		 *
		 * @returns {void}
		 */
		$adminmenu.on( 'focus.adminmenu', '.wp-submenu a', function( event ) {
			if ( $adminmenu.data( 'wp-responsive' ) ) {
				// The menu is in responsive mode, bail
				return;
			}

			$( event.target ).closest( 'li.menu-top' ).addClass( 'opensub' );

			/**
			 * Closes the submenu on blur from the menu item.
			 *
			 * @param {Event} event The event object.
			 *
			 * @returns {void}
			 */
		}).on( 'blur.adminmenu', '.wp-submenu a', function( event ) {
			if ( $adminmenu.data( 'wp-responsive' ) ) {
				return;
			}

			$( event.target ).closest( 'li.menu-top' ).removeClass( 'opensub' );

			/**
			 * Adjusts the size for the submenu.
			 *
			 * @returns {void}
			 */
		}).find( 'li.wp-has-submenu.wp-not-current-submenu' ).on( 'focusin.adminmenu', function() {
			adjustSubmenu( $( this ) );
		});
	}

	/*
	 * The `.below-h2` class is here just for backward compatibility with plugins
	 * that are (incorrectly) using it. Do not use. Use `.inline` instead. See #34570.
	 * If '.wp-header-end' is found, append the notices after it otherwise
	 * after the first h1 or h2 heading found within the main content.
	 */
	if ( ! $headerEnd.length ) {
		$headerEnd = $( '.wrap h1, .wrap h2' ).first();
	}
	$( 'div.updated, div.error, div.notice' ).not( '.inline, .below-h2' ).insertAfter( $headerEnd );

	/**
	 * Makes notices dismissible.
	 *
	 * @since 4.4.0
	 *
	 * @returns {void}
	 */
	function makeNoticesDismissible() {
		$( '.notice.is-dismissible' ).each( function() {
			var $el = $( this ),
				$button = $( '<button type="button" class="notice-dismiss"><span class="screen-reader-text"></span></button>' ),
				btnText = commonL10n.dismiss || '';

			// Ensure plain text
			$button.find( '.screen-reader-text' ).text( btnText );
			$button.on( 'click.wp-dismiss-notice', function( event ) {
				event.preventDefault();
				$el.fadeTo( 100, 0, function() {
					$el.slideUp( 100, function() {
						$el.remove();
					});
				});
			});

			$el.append( $button );
		});
	}

	$document.on( 'wp-updates-notice-added wp-plugin-install-error wp-plugin-update-error wp-plugin-delete-error wp-theme-install-error wp-theme-delete-error', makeNoticesDismissible );

	// Init screen meta
	screenMeta.init();

	/**
	 * Checks a checkbox.
	 *
	 * This event needs to be delegated. Ticket #37973.
	 *
	 * @returns {boolean} Returns whether a checkbox is checked or not.
	 */
	$body.on( 'click', 'tbody > tr > .check-column :checkbox', function( event ) {
		// Shift click to select a range of checkboxes.
		if ( 'undefined' == event.shiftKey ) { return true; }
		if ( event.shiftKey ) {
			if ( !lastClicked ) { return true; }
			checks = $( lastClicked ).closest( 'form' ).find( ':checkbox' ).filter( ':visible:enabled' );
			first = checks.index( lastClicked );
			last = checks.index( this );
			checked = $(this).prop('checked');
			if ( 0 < first && 0 < last && first != last ) {
				sliced = ( last > first ) ? checks.slice( first, last ) : checks.slice( last, first );
				sliced.prop( 'checked', function() {
					if ( $(this).closest('tr').is(':visible') )
						return checked;

					return false;
				});
			}
		}
		lastClicked = this;

		// Toggle the "Select all" checkboxes depending if the other ones are all checked or not.
		var unchecked = $(this).closest('tbody').find(':checkbox').filter(':visible:enabled').not(':checked');

		/**
		 * Determines if all checkboxes are checked.
		 *
		 * @returns {boolean} Returns true if there are no unchecked checkboxes.
		 */
		$(this).closest('table').children('thead, tfoot').find(':checkbox').prop('checked', function() {
			return ( 0 === unchecked.length );
		});

		return true;
	});

	/**
	 * Controls all the toggles on bulk toggle change.
	 *
	 * When the bulk checkbox is changed, all the checkboxes in the tables are changed accordingly.
	 * When the shift-button is pressed while changing the bulk checkbox the checkboxes in the table are inverted.
	 *
	 * This event needs to be delegated. Ticket #37973.
	 *
	 * @param {Event} event The event object.
	 *
	 * @returns {boolean}
	 */
	$body.on( 'click.wp-toggle-checkboxes', 'thead .check-column :checkbox, tfoot .check-column :checkbox', function( event ) {
		var $this = $(this),
			$table = $this.closest( 'table' ),
			controlChecked = $this.prop('checked'),
			toggle = event.shiftKey || $this.data('wp-toggle');

		$table.children( 'tbody' ).filter(':visible')
			.children().children('.check-column').find(':checkbox')
			/**
			 * Updates the checked state on the checkbox in the table.
			 *
			 * @returns {boolean} True checks the checkbox, False unchecks the checkbox.
			 */
			.prop('checked', function() {
				if ( $(this).is(':hidden,:disabled') ) {
					return false;
				}

				if ( toggle ) {
					return ! $(this).prop( 'checked' );
				} else if ( controlChecked ) {
					return true;
				}

				return false;
			});

		$table.children('thead,  tfoot').filter(':visible')
			.children().children('.check-column').find(':checkbox')

			/**
			 * Syncs the bulk checkboxes on the top and bottom of the table.
			 *
			 * @returns {boolean} True checks the checkbox, False unchecks the checkbox.
			 */
			.prop('checked', function() {
				if ( toggle ) {
					return false;
				} else if ( controlChecked ) {
					return true;
				}

				return false;
			});
	});

	/**
	 * Shows row actions on focus of its parent container element or any other elements contained within.
	 *
	 * @returns {void}
	 */
	$( '#wpbody-content' ).on({
		focusin: function() {
			clearTimeout( transitionTimeout );
			focusedRowActions = $( this ).find( '.row-actions' );
			// transitionTimeout is necessary for Firefox, but Chrome won't remove the CSS class without a little help.
			$( '.row-actions' ).not( this ).removeClass( 'visible' );
			focusedRowActions.addClass( 'visible' );
		},
		focusout: function() {
			// Tabbing between post title and .row-actions links needs a brief pause, otherwise
			// the .row-actions div gets hidden in transit in some browsers (ahem, Firefox).
			transitionTimeout = setTimeout( function() {
				focusedRowActions.removeClass( 'visible' );
			}, 30 );
		}
	}, '.has-row-actions' );

	// Toggle list table rows on small screens
	$( 'tbody' ).on( 'click', '.toggle-row', function() {
		$( this ).closest( 'tr' ).toggleClass( 'is-expanded' );
	});

	$('#default-password-nag-no').click( function() {
		setUserSetting('default_password_nag', 'hide');
		$('div.default-password-nag').hide();
		return false;
	});

	/**
	 * Handles tab keypresses in theme and plugin editor textareas.
	 *
	 * @param {Event} e The event object.
	 *
	 * @returns {void}
	 */
	$('#newcontent').bind('keydown.wpevent_InsertTab', function(e) {
		var el = e.target, selStart, selEnd, val, scroll, sel;

		// After pressing escape key (keyCode: 27), the tab key should tab out of the textarea.
		if ( e.keyCode == 27 ) {
			// when pressing Escape: Opera 12 and 27 blur form fields, IE 8 clears them
			e.preventDefault();
			$(el).data('tab-out', true);
			return;
		}

		// Only listen for plain tab key (keyCode: 9) without any modifiers.
		if ( e.keyCode != 9 || e.ctrlKey || e.altKey || e.shiftKey )
			return;

		// After tabbing out, reset it so next time the tab key can be used again.
		if ( $(el).data('tab-out') ) {
			$(el).data('tab-out', false);
			return;
		}

		selStart = el.selectionStart;
		selEnd = el.selectionEnd;
		val = el.value;

		// If any text is selected, replace the selection with a tab character.
		if ( document.selection ) {
			el.focus();
			sel = document.selection.createRange();
			sel.text = '\t';
		} else if ( selStart >= 0 ) {
			scroll = this.scrollTop;
			el.value = val.substring(0, selStart).concat('\t', val.substring(selEnd) );
			el.selectionStart = el.selectionEnd = selStart + 1;
			this.scrollTop = scroll;
		}

		// Cancel the regular tab functionality, to prevent losing focus of the textarea.
		if ( e.stopPropagation )
			e.stopPropagation();
		if ( e.preventDefault )
			e.preventDefault();
	});

	// Reset page number variable for new filters/searches but not for bulk actions. See #17685.
	if ( pageInput.length ) {

		/**
		 * Handles pagination variable when filtering the list table.
		 *
		 * Set the pagination argument to the first page when the post-filter form is submitted.
		 * This happens when pressing the 'filter' button on the list table page.
		 *
		 * The pagination argument should not be touched when the bulk action dropdowns are set to do anything.
		 *
		 * The form closest to the pageInput is the post-filter form.
		 *
		 * @returns {void}
		 */
		pageInput.closest('form').submit( function() {
			/*
			 * action = bulk action dropdown at the top of the table
			 * action2 = bulk action dropdow at the bottom of the table
			 */
			if ( $('select[name="action"]').val() == -1 && $('select[name="action2"]').val() == -1 && pageInput.val() == currentPage )
				pageInput.val('1');
		});
	}

	/**
	 * Resets the bulk actions when the search button is clicked.
	 *
	 * @returns {void}
	 */
	$('.search-box input[type="search"], .search-box input[type="submit"]').mousedown(function () {
		$('select[name^="action"]').val('-1');
	});

	/**
	 * Scrolls into view when focus.scroll-into-view is triggered.
	 *
	 * @param {Event} e The event object.
	 *
	 * @returns {void}
 	 */
	$('#contextual-help-link, #show-settings-link').on( 'focus.scroll-into-view', function(e){
		if ( e.target.scrollIntoView )
			e.target.scrollIntoView(false);
	});

	/**
	 * Disables the submit upload buttons when no data is entered.
	 *
	 * @returns {void}
	 */
	(function(){
		var button, input, form = $('form.wp-upload-form');

		// Exit when no upload form is found.
		if ( ! form.length )
			return;

		button = form.find('input[type="submit"]');
		input = form.find('input[type="file"]');

		/**
		 * Determines if any data is entered in any file upload input.
		 *
		 * @since 3.5.0
		 *
		 * @returns {void}
		 */
		function toggleUploadButton() {
			// When no inputs have a value, disable the upload buttons.
			button.prop('disabled', '' === input.map( function() {
				return $(this).val();
			}).get().join(''));
		}

		// Update the status initially.
		toggleUploadButton();
		// Update the status when any file input changes.
		input.on('change', toggleUploadButton);
	})();

	/**
	 * Pins the menu while distraction-free writing is enabled.
	 *
	 * @param {Event} event Event data.
	 *
	 * @since 4.1.0
	 *
	 * @returns {void}
	 */
	function pinMenu( event ) {
		var windowPos = $window.scrollTop(),
			resizing = ! event || event.type !== 'scroll';

		if ( isIOS || isIE8 || $adminmenu.data( 'wp-responsive' ) ) {
			return;
		}

		/*
		 * When the menu is higher than the window and smaller than the entire page.
		 * It should be adjusted to be able to see the entire menu.
		 *
		 * Otherwise it can be accessed normally.
		 */
		if ( height.menu + height.adminbar < height.window ||
			height.menu + height.adminbar + 20 > height.wpwrap ) {
			unpinMenu();
			return;
		}

		menuIsPinned = true;

		// If the menu is higher than the window, compensate on scroll.
		if ( height.menu + height.adminbar > height.window ) {
			// Check for overscrolling, this happens when swiping up at the top of the document in modern browsers.
			if ( windowPos < 0 ) {
				// Stick the menu to the top.
				if ( ! pinnedMenuTop ) {
					pinnedMenuTop = true;
					pinnedMenuBottom = false;

					$adminMenuWrap.css({
						position: 'fixed',
						top: '',
						bottom: ''
					});
				}

				return;
			} else if ( windowPos + height.window > $document.height() - 1 ) {
				// When overscrolling at the bottom, stick the menu to the bottom.
				if ( ! pinnedMenuBottom ) {
					pinnedMenuBottom = true;
					pinnedMenuTop = false;

					$adminMenuWrap.css({
						position: 'fixed',
						top: '',
						bottom: 0
					});
				}

				return;
			}

			if ( windowPos > lastScrollPosition ) {
				// When a down scroll has been detected.

				// If it was pinned to the top, unpin and calculate relative scroll.
				if ( pinnedMenuTop ) {
					pinnedMenuTop = false;
					// Calculate new offset position.
					menuTop = $adminMenuWrap.offset().top - height.adminbar - ( windowPos - lastScrollPosition );

					if ( menuTop + height.menu + height.adminbar < windowPos + height.window ) {
						menuTop = windowPos + height.window - height.menu - height.adminbar;
					}

					$adminMenuWrap.css({
						position: 'absolute',
						top: menuTop,
						bottom: ''
					});
				} else if ( ! pinnedMenuBottom && $adminMenuWrap.offset().top + height.menu < windowPos + height.window ) {
					// Pin it to the bottom.
					pinnedMenuBottom = true;

					$adminMenuWrap.css({
						position: 'fixed',
						top: '',
						bottom: 0
					});
				}
			} else if ( windowPos < lastScrollPosition ) {
				// When a scroll up is detected.

				// If it was pinned to the bottom, unpin and calculate relative scroll.
				if ( pinnedMenuBottom ) {
					pinnedMenuBottom = false;

					// Calculate new offset position.
					menuTop = $adminMenuWrap.offset().top - height.adminbar + ( lastScrollPosition - windowPos );

					if ( menuTop + height.menu > windowPos + height.window ) {
						menuTop = windowPos;
					}

					$adminMenuWrap.css({
						position: 'absolute',
						top: menuTop,
						bottom: ''
					});
				} else if ( ! pinnedMenuTop && $adminMenuWrap.offset().top >= windowPos + height.adminbar ) {

					// Pin it to the top.
					pinnedMenuTop = true;

					$adminMenuWrap.css({
						position: 'fixed',
						top: '',
						bottom: ''
					});
				}
			} else if ( resizing ) {
				// Window is being resized.

				pinnedMenuTop = pinnedMenuBottom = false;

				// Calculate the new offset.
				menuTop = windowPos + height.window - height.menu - height.adminbar - 1;

				if ( menuTop > 0 ) {
					$adminMenuWrap.css({
						position: 'absolute',
						top: menuTop,
						bottom: ''
					});
				} else {
					unpinMenu();
				}
			}
		}

		lastScrollPosition = windowPos;
	}

	/**
	 * Determines the height of certain elements.
	 *
	 * @since 4.1.0
	 *
	 * @returns {void}
	 */
	function resetHeights() {
		height = {
			window: $window.height(),
			wpwrap: $wpwrap.height(),
			adminbar: $adminbar.height(),
			menu: $adminMenuWrap.height()
		};
	}

	/**
	 * Unpins the menu.
	 *
	 * @since 4.1.0
	 *
	 * @returns {void}
	 */
	function unpinMenu() {
		if ( isIOS || ! menuIsPinned ) {
			return;
		}

		pinnedMenuTop = pinnedMenuBottom = menuIsPinned = false;
		$adminMenuWrap.css({
			position: '',
			top: '',
			bottom: ''
		});
	}

	/**
	 * Pins and unpins the menu when applicable.
	 *
	 * @since 4.1.0
	 *
	 * @returns {void}
	 */
	function setPinMenu() {
		resetHeights();

		if ( $adminmenu.data('wp-responsive') ) {
			$body.removeClass( 'sticky-menu' );
			unpinMenu();
		} else if ( height.menu + height.adminbar > height.window ) {
			pinMenu();
			$body.removeClass( 'sticky-menu' );
		} else {
			$body.addClass( 'sticky-menu' );
			unpinMenu();
		}
	}

	if ( ! isIOS ) {
		$window.on( 'scroll.pin-menu', pinMenu );
		$document.on( 'tinymce-editor-init.pin-menu', function( event, editor ) {
			editor.on( 'wp-autoresize', resetHeights );
		});
	}

	/**
	 * Changes the sortables and responsiveness of metaboxes.
	 *
	 * @since 3.8.0
	 *
	 *@returns {void}
	 */
	window.wpResponsive = {

		/**
		 * Initializes the wpResponsive object.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		init: function() {
			var self = this;

			// Modify functionality based on custom activate/deactivate event
			$document.on( 'wp-responsive-activate.wp-responsive', function() {
				self.activate();
			}).on( 'wp-responsive-deactivate.wp-responsive', function() {
				self.deactivate();
			});

			$( '#wp-admin-bar-menu-toggle a' ).attr( 'aria-expanded', 'false' );

			// Toggle sidebar when toggle is clicked.
			$( '#wp-admin-bar-menu-toggle' ).on( 'click.wp-responsive', function( event ) {
				event.preventDefault();

				// close any open toolbar submenus.
				$adminbar.find( '.hover' ).removeClass( 'hover' );

				$wpwrap.toggleClass( 'wp-responsive-open' );
				if ( $wpwrap.hasClass( 'wp-responsive-open' ) ) {
					$(this).find('a').attr( 'aria-expanded', 'true' );
					$( '#adminmenu a:first' ).focus();
				} else {
					$(this).find('a').attr( 'aria-expanded', 'false' );
				}
			} );

			// Add menu events.
			$adminmenu.on( 'click.wp-responsive', 'li.wp-has-submenu > a', function( event ) {
				if ( ! $adminmenu.data('wp-responsive') ) {
					return;
				}

				$( this ).parent( 'li' ).toggleClass( 'selected' );
				event.preventDefault();
			});

			self.trigger();
			$document.on( 'wp-window-resized.wp-responsive', $.proxy( this.trigger, this ) );

			// This needs to run later as UI Sortable may be initialized later on $(document).ready().
			$window.on( 'load.wp-responsive', function() {
				var width = navigator.userAgent.indexOf('AppleWebKit/') > -1 ? $window.width() : window.innerWidth;

				if ( width <= 782 ) {
					self.disableSortables();
				}
			});
		},

		/**
		 * Changes properties of body and admin menu.
		 *
		 * Pins and unpins the menu and adds the auto-fold class to the body.
		 * Makes the admin menu responsive and disables the metabox sortables.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		activate: function() {
			setPinMenu();

			if ( ! $body.hasClass( 'auto-fold' ) ) {
				$body.addClass( 'auto-fold' );
			}

			$adminmenu.data( 'wp-responsive', 1 );
			this.disableSortables();
		},

		/**
		 * Changes properties of admin menu and enables metabox sortables.
		 *
		 * Pin and unpin the menu.
		 * Removes the responsiveness of the admin menu and enables the metabox sortables.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		deactivate: function() {
			setPinMenu();
			$adminmenu.removeData('wp-responsive');
			this.enableSortables();
		},

		/**
		 * Sets the responsiveness and enables the overlay based on the viewport width.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		trigger: function() {
			var viewportWidth = getViewportWidth();

			// Exclude IE < 9, it doesn't support @media CSS rules.
			if ( ! viewportWidth ) {
				return;
			}

			if ( viewportWidth <= 782 ) {
				if ( ! wpResponsiveActive ) {
					$document.trigger( 'wp-responsive-activate' );
					wpResponsiveActive = true;
				}
			} else {
				if ( wpResponsiveActive ) {
					$document.trigger( 'wp-responsive-deactivate' );
					wpResponsiveActive = false;
				}
			}

			if ( viewportWidth <= 480 ) {
				this.enableOverlay();
			} else {
				this.disableOverlay();
			}
		},

		/**
		 * Inserts a responsive overlay and toggles the window.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		enableOverlay: function() {
			if ( $overlay.length === 0 ) {
				$overlay = $( '<div id="wp-responsive-overlay"></div>' )
					.insertAfter( '#wpcontent' )
					.hide()
					.on( 'click.wp-responsive', function() {
						$toolbar.find( '.menupop.hover' ).removeClass( 'hover' );
						$( this ).hide();
					});
			}

			$toolbarPopups.on( 'click.wp-responsive', function() {
				$overlay.show();
			});
		},

		/**
		 * Disables the responsive overlay and removes the overlay.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		disableOverlay: function() {
			$toolbarPopups.off( 'click.wp-responsive' );
			$overlay.hide();
		},

		/**
		 * Disables sortables.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		disableSortables: function() {
			if ( $sortables.length ) {
				try {
					$sortables.sortable( 'disable' );
				} catch ( e ) {}
			}
		},

		/**
		 * Enables sortables.
		 *
		 * @since 3.8.0
		 *
		 * @returns {void}
		 */
		enableSortables: function() {
			if ( $sortables.length ) {
				try {
					$sortables.sortable( 'enable' );
				} catch ( e ) {}
			}
		}
	};

	/**
	 * Add an ARIA role `button` to elements that behave like UI controls when JavaScript is on.
	 *
	 * @since 4.5.0
	 *
	 * @returns {void}
	 */
	function aria_button_if_js() {
		$( '.aria-button-if-js' ).attr( 'role', 'button' );
	}

	$( document ).ajaxComplete( function() {
		aria_button_if_js();
	});

	/**
	 * Get the viewport width.
	 *
	 * @since 4.7.0
	 *
	 * @returns {number|boolean} The current viewport width or false if the
	 *                           browser doesn't support innerWidth (IE < 9).
	 */
	function getViewportWidth() {
		var viewportWidth = false;

		if ( window.innerWidth ) {
			// On phones, window.innerWidth is affected by zooming.
			viewportWidth = Math.max( window.innerWidth, document.documentElement.clientWidth );
		}

		return viewportWidth;
	}

	/**
	 * Sets the admin menu collapsed/expanded state.
	 *
	 * Sets the global variable `menuState` and triggers a custom event passing
	 * the current menu state.
	 *
	 * @since 4.7.0
	 *
	 * @returns {void}
	 */
	function setMenuState() {
		var viewportWidth = getViewportWidth() || 961;

		if ( viewportWidth <= 782  ) {
			menuState = 'responsive';
		} else if ( $body.hasClass( 'folded' ) || ( $body.hasClass( 'auto-fold' ) && viewportWidth <= 960 && viewportWidth > 782 ) ) {
			menuState = 'folded';
		} else {
			menuState = 'open';
		}

		$document.trigger( 'wp-menu-state-set', { state: menuState } );
	}

	// Set the menu state when the window gets resized.
	$document.on( 'wp-window-resized.set-menu-state', setMenuState );

	/**
	 * Sets ARIA attributes on the collapse/expand menu button.
	 *
	 * When the admin menu is open or folded, updates the `aria-expanded` and
	 * `aria-label` attributes of the button to give feedback to assistive
	 * technologies. In the responsive view, the button is always hidden.
	 *
	 * @since 4.7.0
	 *
	 * @returns {void}
	 */
	$document.on( 'wp-menu-state-set wp-collapse-menu', function( event, eventData ) {
		var $collapseButton = $( '#collapse-button' ),
			ariaExpanded = 'true',
			ariaLabelText = commonL10n.collapseMenu;

		if ( 'folded' === eventData.state ) {
			ariaExpanded = 'false';
			ariaLabelText = commonL10n.expandMenu;
		}

		$collapseButton.attr({
			'aria-expanded': ariaExpanded,
			'aria-label': ariaLabelText
		});
	});

	window.wpResponsive.init();
	setPinMenu();
	setMenuState();
	currentMenuItemHasPopup();
	makeNoticesDismissible();
	aria_button_if_js();

	$document.on( 'wp-pin-menu wp-window-resized.pin-menu postboxes-columnchange.pin-menu postbox-toggled.pin-menu wp-collapse-menu.pin-menu wp-scroll-start.pin-menu', setPinMenu );

	// Set initial focus on a specific element.
	$( '.wp-initial-focus' ).focus();

	// Toggle update details on update-core.php.
	$body.on( 'click', '.js-update-details-toggle', function() {
		var $updateNotice = $( this ).closest( '.js-update-details' ),
			$progressDiv = $( '#' + $updateNotice.data( 'update-details' ) );

		/*
		 * When clicking on "Show details" move the progress div below the update
		 * notice. Make sure it gets moved just the first time.
		 */
		if ( ! $progressDiv.hasClass( 'update-details-moved' ) ) {
			$progressDiv.insertAfter( $updateNotice ).addClass( 'update-details-moved' );
		}

		// Toggle the progress div visibility.
		$progressDiv.toggle();
		// Toggle the Show Details button expanded state.
		$( this ).attr( 'aria-expanded', $progressDiv.is( ':visible' ) );
	});
});

// Fire a custom jQuery event at the end of window resize.
( function() {
	var timeout;

	/**
	 * Triggers the WP window-resize event.
	 *
	 * @since 3.8.0
	 *
	 * @returns {void}
	 */
	function triggerEvent() {
		$document.trigger( 'wp-window-resized' );
	}

	/**
	 * Fires the trigger event again after 200 ms.
	 *
	 * @since 3.8.0
	 *
	 * @returns {void}
	 */
	function fireOnce() {
		window.clearTimeout( timeout );
		timeout = window.setTimeout( triggerEvent, 200 );
	}

	$window.on( 'resize.wp-fire-once', fireOnce );
}());

// Make Windows 8 devices play along nicely.
(function(){
	if ( '-ms-user-select' in document.documentElement.style && navigator.userAgent.match(/IEMobile\/10\.0/) ) {
		var msViewportStyle = document.createElement( 'style' );
		msViewportStyle.appendChild(
			document.createTextNode( '@-ms-viewport{width:auto!important}' )
		);
		document.getElementsByTagName( 'head' )[0].appendChild( msViewportStyle );
	}
})();

}( jQuery, window ));
