/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.io/license
 */
import { DOCUMENT, CommonModule } from '@angular/common';
import { Inject, Injectable, Optional, SkipSelf, QueryList, Directive, ElementRef, Input, NgZone, InjectionToken, EventEmitter, Output, NgModule, defineInjectable, inject } from '@angular/core';
import { Subject, Subscription, of } from 'rxjs';
import { UP_ARROW, DOWN_ARROW, LEFT_ARROW, RIGHT_ARROW, TAB, A, Z, ZERO, NINE } from '@angular/cdk/keycodes';
import { debounceTime, filter, map, tap, take } from 'rxjs/operators';
import { Platform, supportsPassiveEventListeners, PlatformModule } from '@angular/cdk/platform';
import { coerceBooleanProperty } from '@angular/cdk/coercion';
import { ContentObserver, ObserversModule } from '@angular/cdk/observers';

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */

/** *
 * IDs are deliminated by an empty space, as per the spec.
  @type {?} */
const ID_DELIMINATOR = ' ';
/**
 * Adds the given ID to the specified ARIA attribute on an element.
 * Used for attributes such as aria-labelledby, aria-owns, etc.
 * @param {?} el
 * @param {?} attr
 * @param {?} id
 * @return {?}
 */
function addAriaReferencedId(el, attr, id) {
    /** @type {?} */
    const ids = getAriaReferenceIds(el, attr);
    if (ids.some(existingId => existingId.trim() == id.trim())) {
        return;
    }
    ids.push(id.trim());
    el.setAttribute(attr, ids.join(ID_DELIMINATOR));
}
/**
 * Removes the given ID from the specified ARIA attribute on an element.
 * Used for attributes such as aria-labelledby, aria-owns, etc.
 * @param {?} el
 * @param {?} attr
 * @param {?} id
 * @return {?}
 */
function removeAriaReferencedId(el, attr, id) {
    /** @type {?} */
    const ids = getAriaReferenceIds(el, attr);
    /** @type {?} */
    const filteredIds = ids.filter(val => val != id.trim());
    el.setAttribute(attr, filteredIds.join(ID_DELIMINATOR));
}
/**
 * Gets the list of IDs referenced by the given ARIA attribute on an element.
 * Used for attributes such as aria-labelledby, aria-owns, etc.
 * @param {?} el
 * @param {?} attr
 * @return {?}
 */
function getAriaReferenceIds(el, attr) {
    // Get string array of all individual ids (whitespace deliminated) in the attribute value
    return (el.getAttribute(attr) || '').match(/\S+/g) || [];
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/** *
 * ID used for the body container where all messages are appended.
  @type {?} */
const MESSAGES_CONTAINER_ID = 'cdk-describedby-message-container';
/** *
 * ID prefix used for each created message element.
  @type {?} */
const CDK_DESCRIBEDBY_ID_PREFIX = 'cdk-describedby-message';
/** *
 * Attribute given to each host element that is described by a message element.
  @type {?} */
const CDK_DESCRIBEDBY_HOST_ATTRIBUTE = 'cdk-describedby-host';
/** *
 * Global incremental identifier for each registered message element.
  @type {?} */
let nextId = 0;
/** *
 * Global map of all registered message elements that have been placed into the document.
  @type {?} */
const messageRegistry = new Map();
/** *
 * Container for all registered messages.
  @type {?} */
let messagesContainer = null;
/**
 * Utility that creates visually hidden elements with a message content. Useful for elements that
 * want to use aria-describedby to further describe themselves without adding additional visual
 * content.
 * \@docs-private
 */
class AriaDescriber {
    /**
     * @param {?} _document
     */
    constructor(_document) {
        this._document = _document;
    }
    /**
     * Adds to the host element an aria-describedby reference to a hidden element that contains
     * the message. If the same message has already been registered, then it will reuse the created
     * message element.
     * @param {?} hostElement
     * @param {?} message
     * @return {?}
     */
    describe(hostElement, message) {
        if (!this._canBeDescribed(hostElement, message)) {
            return;
        }
        if (!messageRegistry.has(message)) {
            this._createMessageElement(message);
        }
        if (!this._isElementDescribedByMessage(hostElement, message)) {
            this._addMessageReference(hostElement, message);
        }
    }
    /**
     * Removes the host element's aria-describedby reference to the message element.
     * @param {?} hostElement
     * @param {?} message
     * @return {?}
     */
    removeDescription(hostElement, message) {
        if (!this._canBeDescribed(hostElement, message)) {
            return;
        }
        if (this._isElementDescribedByMessage(hostElement, message)) {
            this._removeMessageReference(hostElement, message);
        }
        /** @type {?} */
        const registeredMessage = messageRegistry.get(message);
        if (registeredMessage && registeredMessage.referenceCount === 0) {
            this._deleteMessageElement(message);
        }
        if (messagesContainer && messagesContainer.childNodes.length === 0) {
            this._deleteMessagesContainer();
        }
    }
    /**
     * Unregisters all created message elements and removes the message container.
     * @return {?}
     */
    ngOnDestroy() {
        /** @type {?} */
        const describedElements = this._document.querySelectorAll(`[${CDK_DESCRIBEDBY_HOST_ATTRIBUTE}]`);
        for (let i = 0; i < describedElements.length; i++) {
            this._removeCdkDescribedByReferenceIds(describedElements[i]);
            describedElements[i].removeAttribute(CDK_DESCRIBEDBY_HOST_ATTRIBUTE);
        }
        if (messagesContainer) {
            this._deleteMessagesContainer();
        }
        messageRegistry.clear();
    }
    /**
     * Creates a new element in the visually hidden message container element with the message
     * as its content and adds it to the message registry.
     * @param {?} message
     * @return {?}
     */
    _createMessageElement(message) {
        /** @type {?} */
        const messageElement = this._document.createElement('div');
        messageElement.setAttribute('id', `${CDK_DESCRIBEDBY_ID_PREFIX}-${nextId++}`);
        messageElement.appendChild(/** @type {?} */ ((this._document.createTextNode(message))));
        this._createMessagesContainer(); /** @type {?} */
        ((messagesContainer)).appendChild(messageElement);
        messageRegistry.set(message, { messageElement, referenceCount: 0 });
    }
    /**
     * Deletes the message element from the global messages container.
     * @param {?} message
     * @return {?}
     */
    _deleteMessageElement(message) {
        /** @type {?} */
        const registeredMessage = messageRegistry.get(message);
        /** @type {?} */
        const messageElement = registeredMessage && registeredMessage.messageElement;
        if (messagesContainer && messageElement) {
            messagesContainer.removeChild(messageElement);
        }
        messageRegistry.delete(message);
    }
    /**
     * Creates the global container for all aria-describedby messages.
     * @return {?}
     */
    _createMessagesContainer() {
        if (!messagesContainer) {
            /** @type {?} */
            const preExistingContainer = this._document.getElementById(MESSAGES_CONTAINER_ID);
            // When going from the server to the client, we may end up in a situation where there's
            // already a container on the page, but we don't have a reference to it. Clear the
            // old container so we don't get duplicates. Doing this, instead of emptying the previous
            // container, should be slightly faster.
            if (preExistingContainer) {
                /** @type {?} */ ((preExistingContainer.parentNode)).removeChild(preExistingContainer);
            }
            messagesContainer = this._document.createElement('div');
            messagesContainer.id = MESSAGES_CONTAINER_ID;
            messagesContainer.setAttribute('aria-hidden', 'true');
            messagesContainer.style.display = 'none';
            this._document.body.appendChild(messagesContainer);
        }
    }
    /**
     * Deletes the global messages container.
     * @return {?}
     */
    _deleteMessagesContainer() {
        if (messagesContainer && messagesContainer.parentNode) {
            messagesContainer.parentNode.removeChild(messagesContainer);
            messagesContainer = null;
        }
    }
    /**
     * Removes all cdk-describedby messages that are hosted through the element.
     * @param {?} element
     * @return {?}
     */
    _removeCdkDescribedByReferenceIds(element) {
        /** @type {?} */
        const originalReferenceIds = getAriaReferenceIds(element, 'aria-describedby')
            .filter(id => id.indexOf(CDK_DESCRIBEDBY_ID_PREFIX) != 0);
        element.setAttribute('aria-describedby', originalReferenceIds.join(' '));
    }
    /**
     * Adds a message reference to the element using aria-describedby and increments the registered
     * message's reference count.
     * @param {?} element
     * @param {?} message
     * @return {?}
     */
    _addMessageReference(element, message) {
        /** @type {?} */
        const registeredMessage = /** @type {?} */ ((messageRegistry.get(message)));
        // Add the aria-describedby reference and set the
        // describedby_host attribute to mark the element.
        addAriaReferencedId(element, 'aria-describedby', registeredMessage.messageElement.id);
        element.setAttribute(CDK_DESCRIBEDBY_HOST_ATTRIBUTE, '');
        registeredMessage.referenceCount++;
    }
    /**
     * Removes a message reference from the element using aria-describedby
     * and decrements the registered message's reference count.
     * @param {?} element
     * @param {?} message
     * @return {?}
     */
    _removeMessageReference(element, message) {
        /** @type {?} */
        const registeredMessage = /** @type {?} */ ((messageRegistry.get(message)));
        registeredMessage.referenceCount--;
        removeAriaReferencedId(element, 'aria-describedby', registeredMessage.messageElement.id);
        element.removeAttribute(CDK_DESCRIBEDBY_HOST_ATTRIBUTE);
    }
    /**
     * Returns true if the element has been described by the provided message ID.
     * @param {?} element
     * @param {?} message
     * @return {?}
     */
    _isElementDescribedByMessage(element, message) {
        /** @type {?} */
        const referenceIds = getAriaReferenceIds(element, 'aria-describedby');
        /** @type {?} */
        const registeredMessage = messageRegistry.get(message);
        /** @type {?} */
        const messageId = registeredMessage && registeredMessage.messageElement.id;
        return !!messageId && referenceIds.indexOf(messageId) != -1;
    }
    /**
     * Determines whether a message can be described on a particular element.
     * @param {?} element
     * @param {?} message
     * @return {?}
     */
    _canBeDescribed(element, message) {
        return element.nodeType === this._document.ELEMENT_NODE && message != null &&
            !!`${message}`.trim();
    }
}
AriaDescriber.decorators = [
    { type: Injectable, args: [{ providedIn: 'root' },] },
];
/** @nocollapse */
AriaDescriber.ctorParameters = () => [
    { type: undefined, decorators: [{ type: Inject, args: [DOCUMENT,] }] }
];
/** @nocollapse */ AriaDescriber.ngInjectableDef = defineInjectable({ factory: function AriaDescriber_Factory() { return new AriaDescriber(inject(DOCUMENT)); }, token: AriaDescriber, providedIn: "root" });
/**
 * \@docs-private \@deprecated \@breaking-change 7.0.0
 * @param {?} parentDispatcher
 * @param {?} _document
 * @return {?}
 */
function ARIA_DESCRIBER_PROVIDER_FACTORY(parentDispatcher, _document) {
    return parentDispatcher || new AriaDescriber(_document);
}
/** *
 * \@docs-private \@deprecated \@breaking-change 7.0.0
  @type {?} */
const ARIA_DESCRIBER_PROVIDER = {
    // If there is already an AriaDescriber available, use that. Otherwise, provide a new one.
    provide: AriaDescriber,
    deps: [
        [new Optional(), new SkipSelf(), AriaDescriber],
        /** @type {?} */ (DOCUMENT)
    ],
    useFactory: ARIA_DESCRIBER_PROVIDER_FACTORY
};

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
// unsupported: template constraints.
/**
 * This class manages keyboard events for selectable lists. If you pass it a query list
 * of items, it will set the active item correctly when arrow events occur.
 * @template T
 */
class ListKeyManager {
    /**
     * @param {?} _items
     */
    constructor(_items) {
        this._items = _items;
        this._activeItemIndex = -1;
        this._wrap = false;
        this._letterKeyStream = new Subject();
        this._typeaheadSubscription = Subscription.EMPTY;
        this._vertical = true;
        /**
         * Predicate function that can be used to check whether an item should be skipped
         * by the key manager. By default, disabled items are skipped.
         */
        this._skipPredicateFn = (item) => item.disabled;
        this._pressedLetters = [];
        /**
         * Stream that emits any time the TAB key is pressed, so components can react
         * when focus is shifted off of the list.
         */
        this.tabOut = new Subject();
        /**
         * Stream that emits whenever the active item of the list manager changes.
         */
        this.change = new Subject();
        // We allow for the items to be an array because, in some cases, the consumer may
        // not have access to a QueryList of the items they want to manage (e.g. when the
        // items aren't being collected via `ViewChildren` or `ContentChildren`).
        if (_items instanceof QueryList) {
            _items.changes.subscribe((newItems) => {
                if (this._activeItem) {
                    /** @type {?} */
                    const itemArray = newItems.toArray();
                    /** @type {?} */
                    const newIndex = itemArray.indexOf(this._activeItem);
                    if (newIndex > -1 && newIndex !== this._activeItemIndex) {
                        this._activeItemIndex = newIndex;
                    }
                }
            });
        }
    }
    /**
     * Sets the predicate function that determines which items should be skipped by the
     * list key manager.
     * @param {?} predicate Function that determines whether the given item should be skipped.
     * @return {?}
     */
    skipPredicate(predicate) {
        this._skipPredicateFn = predicate;
        return this;
    }
    /**
     * Configures wrapping mode, which determines whether the active item will wrap to
     * the other end of list when there are no more items in the given direction.
     * @param {?=} shouldWrap Whether the list should wrap when reaching the end.
     * @return {?}
     */
    withWrap(shouldWrap = true) {
        this._wrap = shouldWrap;
        return this;
    }
    /**
     * Configures whether the key manager should be able to move the selection vertically.
     * @param {?=} enabled Whether vertical selection should be enabled.
     * @return {?}
     */
    withVerticalOrientation(enabled = true) {
        this._vertical = enabled;
        return this;
    }
    /**
     * Configures the key manager to move the selection horizontally.
     * Passing in `null` will disable horizontal movement.
     * @param {?} direction Direction in which the selection can be moved.
     * @return {?}
     */
    withHorizontalOrientation(direction) {
        this._horizontal = direction;
        return this;
    }
    /**
     * Turns on typeahead mode which allows users to set the active item by typing.
     * @param {?=} debounceInterval Time to wait after the last keystroke before setting the active item.
     * @return {?}
     */
    withTypeAhead(debounceInterval = 200) {
        if (this._items.length && this._items.some(item => typeof item.getLabel !== 'function')) {
            throw Error('ListKeyManager items in typeahead mode must implement the `getLabel` method.');
        }
        this._typeaheadSubscription.unsubscribe();
        // Debounce the presses of non-navigational keys, collect the ones that correspond to letters
        // and convert those letters back into a string. Afterwards find the first item that starts
        // with that string and select it.
        this._typeaheadSubscription = this._letterKeyStream.pipe(tap(keyCode => this._pressedLetters.push(keyCode)), debounceTime(debounceInterval), filter(() => this._pressedLetters.length > 0), map(() => this._pressedLetters.join(''))).subscribe(inputString => {
            /** @type {?} */
            const items = this._getItemsArray();
            // Start at 1 because we want to start searching at the item immediately
            // following the current active item.
            for (let i = 1; i < items.length + 1; i++) {
                /** @type {?} */
                const index = (this._activeItemIndex + i) % items.length;
                /** @type {?} */
                const item = items[index];
                if (!this._skipPredicateFn(item) && /** @type {?} */ ((item.getLabel))().toUpperCase().trim().indexOf(inputString) === 0) {
                    this.setActiveItem(index);
                    break;
                }
            }
            this._pressedLetters = [];
        });
        return this;
    }
    /**
     * @param {?} item
     * @return {?}
     */
    setActiveItem(item) {
        /** @type {?} */
        const previousIndex = this._activeItemIndex;
        this.updateActiveItem(item);
        if (this._activeItemIndex !== previousIndex) {
            this.change.next(this._activeItemIndex);
        }
    }
    /**
     * Sets the active item depending on the key event passed in.
     * @param {?} event Keyboard event to be used for determining which element should be active.
     * @return {?}
     */
    onKeydown(event) {
        /** @type {?} */
        const keyCode = event.keyCode;
        switch (keyCode) {
            case TAB:
                this.tabOut.next();
                return;
            case DOWN_ARROW:
                if (this._vertical) {
                    this.setNextItemActive();
                    break;
                }
                else {
                    return;
                }
            case UP_ARROW:
                if (this._vertical) {
                    this.setPreviousItemActive();
                    break;
                }
                else {
                    return;
                }
            case RIGHT_ARROW:
                if (this._horizontal === 'ltr') {
                    this.setNextItemActive();
                    break;
                }
                else if (this._horizontal === 'rtl') {
                    this.setPreviousItemActive();
                    break;
                }
                else {
                    return;
                }
            case LEFT_ARROW:
                if (this._horizontal === 'ltr') {
                    this.setPreviousItemActive();
                    break;
                }
                else if (this._horizontal === 'rtl') {
                    this.setNextItemActive();
                    break;
                }
                else {
                    return;
                }
            default:
                // Attempt to use the `event.key` which also maps it to the user's keyboard language,
                // otherwise fall back to resolving alphanumeric characters via the keyCode.
                if (event.key && event.key.length === 1) {
                    this._letterKeyStream.next(event.key.toLocaleUpperCase());
                }
                else if ((keyCode >= A && keyCode <= Z) || (keyCode >= ZERO && keyCode <= NINE)) {
                    this._letterKeyStream.next(String.fromCharCode(keyCode));
                }
                // Note that we return here, in order to avoid preventing
                // the default action of non-navigational keys.
                return;
        }
        this._pressedLetters = [];
        event.preventDefault();
    }
    /**
     * Index of the currently active item.
     * @return {?}
     */
    get activeItemIndex() {
        return this._activeItemIndex;
    }
    /**
     * The active item.
     * @return {?}
     */
    get activeItem() {
        return this._activeItem;
    }
    /**
     * Sets the active item to the first enabled item in the list.
     * @return {?}
     */
    setFirstItemActive() {
        this._setActiveItemByIndex(0, 1);
    }
    /**
     * Sets the active item to the last enabled item in the list.
     * @return {?}
     */
    setLastItemActive() {
        this._setActiveItemByIndex(this._items.length - 1, -1);
    }
    /**
     * Sets the active item to the next enabled item in the list.
     * @return {?}
     */
    setNextItemActive() {
        this._activeItemIndex < 0 ? this.setFirstItemActive() : this._setActiveItemByDelta(1);
    }
    /**
     * Sets the active item to a previous enabled item in the list.
     * @return {?}
     */
    setPreviousItemActive() {
        this._activeItemIndex < 0 && this._wrap ? this.setLastItemActive()
            : this._setActiveItemByDelta(-1);
    }
    /**
     * @param {?} item
     * @return {?}
     */
    updateActiveItem(item) {
        /** @type {?} */
        const itemArray = this._getItemsArray();
        /** @type {?} */
        const index = typeof item === 'number' ? item : itemArray.indexOf(item);
        this._activeItemIndex = index;
        this._activeItem = itemArray[index];
    }
    /**
     * Allows setting of the activeItemIndex without any other effects.
     * @deprecated Use `updateActiveItem` instead.
     * \@breaking-change 7.0.0
     * @param {?} index The new activeItemIndex.
     * @return {?}
     */
    updateActiveItemIndex(index) {
        this.updateActiveItem(index);
    }
    /**
     * This method sets the active item, given a list of items and the delta between the
     * currently active item and the new active item. It will calculate differently
     * depending on whether wrap mode is turned on.
     * @param {?} delta
     * @return {?}
     */
    _setActiveItemByDelta(delta) {
        this._wrap ? this._setActiveInWrapMode(delta) : this._setActiveInDefaultMode(delta);
    }
    /**
     * Sets the active item properly given "wrap" mode. In other words, it will continue to move
     * down the list until it finds an item that is not disabled, and it will wrap if it
     * encounters either end of the list.
     * @param {?} delta
     * @return {?}
     */
    _setActiveInWrapMode(delta) {
        /** @type {?} */
        const items = this._getItemsArray();
        for (let i = 1; i <= items.length; i++) {
            /** @type {?} */
            const index = (this._activeItemIndex + (delta * i) + items.length) % items.length;
            /** @type {?} */
            const item = items[index];
            if (!this._skipPredicateFn(item)) {
                this.setActiveItem(index);
                return;
            }
        }
    }
    /**
     * Sets the active item properly given the default mode. In other words, it will
     * continue to move down the list until it finds an item that is not disabled. If
     * it encounters either end of the list, it will stop and not wrap.
     * @param {?} delta
     * @return {?}
     */
    _setActiveInDefaultMode(delta) {
        this._setActiveItemByIndex(this._activeItemIndex + delta, delta);
    }
    /**
     * Sets the active item to the first enabled item starting at the index specified. If the
     * item is disabled, it will move in the fallbackDelta direction until it either
     * finds an enabled item or encounters the end of the list.
     * @param {?} index
     * @param {?} fallbackDelta
     * @return {?}
     */
    _setActiveItemByIndex(index, fallbackDelta) {
        /** @type {?} */
        const items = this._getItemsArray();
        if (!items[index]) {
            return;
        }
        while (this._skipPredicateFn(items[index])) {
            index += fallbackDelta;
            if (!items[index]) {
                return;
            }
        }
        this.setActiveItem(index);
    }
    /**
     * Returns the items as an array.
     * @return {?}
     */
    _getItemsArray() {
        return this._items instanceof QueryList ? this._items.toArray() : this._items;
    }
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/**
 * @template T
 */
class ActiveDescendantKeyManager extends ListKeyManager {
    /**
     * @param {?} index
     * @return {?}
     */
    setActiveItem(index) {
        if (this.activeItem) {
            this.activeItem.setInactiveStyles();
        }
        super.setActiveItem(index);
        if (this.activeItem) {
            this.activeItem.setActiveStyles();
        }
    }
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/**
 * @template T
 */
class FocusKeyManager extends ListKeyManager {
    constructor() {
        super(...arguments);
        this._origin = 'program';
    }
    /**
     * Sets the focus origin that will be passed in to the items for any subsequent `focus` calls.
     * @param {?} origin Focus origin to be used when focusing items.
     * @return {?}
     */
    setFocusOrigin(origin) {
        this._origin = origin;
        return this;
    }
    /**
     * @param {?} item
     * @return {?}
     */
    setActiveItem(item) {
        super.setActiveItem(item);
        if (this.activeItem) {
            this.activeItem.focus(this._origin);
        }
    }
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/**
 * Utility for checking the interactivity of an element, such as whether is is focusable or
 * tabbable.
 */
class InteractivityChecker {
    /**
     * @param {?} _platform
     */
    constructor(_platform) {
        this._platform = _platform;
    }
    /**
     * Gets whether an element is disabled.
     *
     * @param {?} element Element to be checked.
     * @return {?} Whether the element is disabled.
     */
    isDisabled(element) {
        // This does not capture some cases, such as a non-form control with a disabled attribute or
        // a form control inside of a disabled form, but should capture the most common cases.
        return element.hasAttribute('disabled');
    }
    /**
     * Gets whether an element is visible for the purposes of interactivity.
     *
     * This will capture states like `display: none` and `visibility: hidden`, but not things like
     * being clipped by an `overflow: hidden` parent or being outside the viewport.
     *
     * @param {?} element
     * @return {?} Whether the element is visible.
     */
    isVisible(element) {
        return hasGeometry(element) && getComputedStyle(element).visibility === 'visible';
    }
    /**
     * Gets whether an element can be reached via Tab key.
     * Assumes that the element has already been checked with isFocusable.
     *
     * @param {?} element Element to be checked.
     * @return {?} Whether the element is tabbable.
     */
    isTabbable(element) {
        // Nothing is tabbable on the the server 😎
        if (!this._platform.isBrowser) {
            return false;
        }
        /** @type {?} */
        const frameElement = getFrameElement(getWindow(element));
        if (frameElement) {
            /** @type {?} */
            const frameType = frameElement && frameElement.nodeName.toLowerCase();
            // Frame elements inherit their tabindex onto all child elements.
            if (getTabIndexValue(frameElement) === -1) {
                return false;
            }
            // Webkit and Blink consider anything inside of an <object> element as non-tabbable.
            if ((this._platform.BLINK || this._platform.WEBKIT) && frameType === 'object') {
                return false;
            }
            // Webkit and Blink disable tabbing to an element inside of an invisible frame.
            if ((this._platform.BLINK || this._platform.WEBKIT) && !this.isVisible(frameElement)) {
                return false;
            }
        }
        /** @type {?} */
        let nodeName = element.nodeName.toLowerCase();
        /** @type {?} */
        let tabIndexValue = getTabIndexValue(element);
        if (element.hasAttribute('contenteditable')) {
            return tabIndexValue !== -1;
        }
        if (nodeName === 'iframe') {
            // The frames may be tabbable depending on content, but it's not possibly to reliably
            // investigate the content of the frames.
            return false;
        }
        if (nodeName === 'audio') {
            if (!element.hasAttribute('controls')) {
                // By default an <audio> element without the controls enabled is not tabbable.
                return false;
            }
            else if (this._platform.BLINK) {
                // In Blink <audio controls> elements are always tabbable.
                return true;
            }
        }
        if (nodeName === 'video') {
            if (!element.hasAttribute('controls') && this._platform.TRIDENT) {
                // In Trident a <video> element without the controls enabled is not tabbable.
                return false;
            }
            else if (this._platform.BLINK || this._platform.FIREFOX) {
                // In Chrome and Firefox <video controls> elements are always tabbable.
                return true;
            }
        }
        if (nodeName === 'object' && (this._platform.BLINK || this._platform.WEBKIT)) {
            // In all Blink and WebKit based browsers <object> elements are never tabbable.
            return false;
        }
        // In iOS the browser only considers some specific elements as tabbable.
        if (this._platform.WEBKIT && this._platform.IOS && !isPotentiallyTabbableIOS(element)) {
            return false;
        }
        return element.tabIndex >= 0;
    }
    /**
     * Gets whether an element can be focused by the user.
     *
     * @param {?} element Element to be checked.
     * @return {?} Whether the element is focusable.
     */
    isFocusable(element) {
        // Perform checks in order of left to most expensive.
        // Again, naive approach that does not capture many edge cases and browser quirks.
        return isPotentiallyFocusable(element) && !this.isDisabled(element) && this.isVisible(element);
    }
}
InteractivityChecker.decorators = [
    { type: Injectable, args: [{ providedIn: 'root' },] },
];
/** @nocollapse */
InteractivityChecker.ctorParameters = () => [
    { type: Platform }
];
/** @nocollapse */ InteractivityChecker.ngInjectableDef = defineInjectable({ factory: function InteractivityChecker_Factory() { return new InteractivityChecker(inject(Platform)); }, token: InteractivityChecker, providedIn: "root" });
/**
 * Returns the frame element from a window object. Since browsers like MS Edge throw errors if
 * the frameElement property is being accessed from a different host address, this property
 * should be accessed carefully.
 * @param {?} window
 * @return {?}
 */
function getFrameElement(window) {
    try {
        return /** @type {?} */ (window.frameElement);
    }
    catch (e) {
        return null;
    }
}
/**
 * Checks whether the specified element has any geometry / rectangles.
 * @param {?} element
 * @return {?}
 */
function hasGeometry(element) {
    // Use logic from jQuery to check for an invisible element.
    // See https://github.com/jquery/jquery/blob/master/src/css/hiddenVisibleSelectors.js#L12
    return !!(element.offsetWidth || element.offsetHeight ||
        (typeof element.getClientRects === 'function' && element.getClientRects().length));
}
/**
 * Gets whether an element's
 * @param {?} element
 * @return {?}
 */
function isNativeFormElement(element) {
    /** @type {?} */
    let nodeName = element.nodeName.toLowerCase();
    return nodeName === 'input' ||
        nodeName === 'select' ||
        nodeName === 'button' ||
        nodeName === 'textarea';
}
/**
 * Gets whether an element is an `<input type="hidden">`.
 * @param {?} element
 * @return {?}
 */
function isHiddenInput(element) {
    return isInputElement(element) && element.type == 'hidden';
}
/**
 * Gets whether an element is an anchor that has an href attribute.
 * @param {?} element
 * @return {?}
 */
function isAnchorWithHref(element) {
    return isAnchorElement(element) && element.hasAttribute('href');
}
/**
 * Gets whether an element is an input element.
 * @param {?} element
 * @return {?}
 */
function isInputElement(element) {
    return element.nodeName.toLowerCase() == 'input';
}
/**
 * Gets whether an element is an anchor element.
 * @param {?} element
 * @return {?}
 */
function isAnchorElement(element) {
    return element.nodeName.toLowerCase() == 'a';
}
/**
 * Gets whether an element has a valid tabindex.
 * @param {?} element
 * @return {?}
 */
function hasValidTabIndex(element) {
    if (!element.hasAttribute('tabindex') || element.tabIndex === undefined) {
        return false;
    }
    /** @type {?} */
    let tabIndex = element.getAttribute('tabindex');
    // IE11 parses tabindex="" as the value "-32768"
    if (tabIndex == '-32768') {
        return false;
    }
    return !!(tabIndex && !isNaN(parseInt(tabIndex, 10)));
}
/**
 * Returns the parsed tabindex from the element attributes instead of returning the
 * evaluated tabindex from the browsers defaults.
 * @param {?} element
 * @return {?}
 */
function getTabIndexValue(element) {
    if (!hasValidTabIndex(element)) {
        return null;
    }
    /** @type {?} */
    const tabIndex = parseInt(element.getAttribute('tabindex') || '', 10);
    return isNaN(tabIndex) ? -1 : tabIndex;
}
/**
 * Checks whether the specified element is potentially tabbable on iOS
 * @param {?} element
 * @return {?}
 */
function isPotentiallyTabbableIOS(element) {
    /** @type {?} */
    let nodeName = element.nodeName.toLowerCase();
    /** @type {?} */
    let inputType = nodeName === 'input' && (/** @type {?} */ (element)).type;
    return inputType === 'text'
        || inputType === 'password'
        || nodeName === 'select'
        || nodeName === 'textarea';
}
/**
 * Gets whether an element is potentially focusable without taking current visible/disabled state
 * into account.
 * @param {?} element
 * @return {?}
 */
function isPotentiallyFocusable(element) {
    // Inputs are potentially focusable *unless* they're type="hidden".
    if (isHiddenInput(element)) {
        return false;
    }
    return isNativeFormElement(element) ||
        isAnchorWithHref(element) ||
        element.hasAttribute('contenteditable') ||
        hasValidTabIndex(element);
}
/**
 * Gets the parent window of a DOM node with regards of being inside of an iframe.
 * @param {?} node
 * @return {?}
 */
function getWindow(node) {
    return node.ownerDocument.defaultView || window;
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/**
 * Class that allows for trapping focus within a DOM element.
 *
 * This class currently uses a relatively simple approach to focus trapping.
 * It assumes that the tab order is the same as DOM order, which is not necessarily true.
 * Things like `tabIndex > 0`, flex `order`, and shadow roots can cause to two to misalign.
 */
class FocusTrap {
    /**
     * @param {?} _element
     * @param {?} _checker
     * @param {?} _ngZone
     * @param {?} _document
     * @param {?=} deferAnchors
     */
    constructor(_element, _checker, _ngZone, _document, deferAnchors = false) {
        this._element = _element;
        this._checker = _checker;
        this._ngZone = _ngZone;
        this._document = _document;
        this._hasAttached = false;
        this._enabled = true;
        if (!deferAnchors) {
            this.attachAnchors();
        }
    }
    /**
     * Whether the focus trap is active.
     * @return {?}
     */
    get enabled() { return this._enabled; }
    /**
     * @param {?} val
     * @return {?}
     */
    set enabled(val) {
        this._enabled = val;
        if (this._startAnchor && this._endAnchor) {
            this._startAnchor.tabIndex = this._endAnchor.tabIndex = this._enabled ? 0 : -1;
        }
    }
    /**
     * Destroys the focus trap by cleaning up the anchors.
     * @return {?}
     */
    destroy() {
        if (this._startAnchor && this._startAnchor.parentNode) {
            this._startAnchor.parentNode.removeChild(this._startAnchor);
        }
        if (this._endAnchor && this._endAnchor.parentNode) {
            this._endAnchor.parentNode.removeChild(this._endAnchor);
        }
        this._startAnchor = this._endAnchor = null;
    }
    /**
     * Inserts the anchors into the DOM. This is usually done automatically
     * in the constructor, but can be deferred for cases like directives with `*ngIf`.
     * @return {?} Whether the focus trap managed to attach successfuly. This may not be the case
     * if the target element isn't currently in the DOM.
     */
    attachAnchors() {
        // If we're not on the browser, there can be no focus to trap.
        if (this._hasAttached) {
            return true;
        }
        this._ngZone.runOutsideAngular(() => {
            if (!this._startAnchor) {
                this._startAnchor = this._createAnchor(); /** @type {?} */
                ((this._startAnchor)).addEventListener('focus', () => this.focusLastTabbableElement());
            }
            if (!this._endAnchor) {
                this._endAnchor = this._createAnchor(); /** @type {?} */
                ((this._endAnchor)).addEventListener('focus', () => this.focusFirstTabbableElement());
            }
        });
        if (this._element.parentNode) {
            this._element.parentNode.insertBefore(/** @type {?} */ ((this._startAnchor)), this._element);
            this._element.parentNode.insertBefore(/** @type {?} */ ((this._endAnchor)), this._element.nextSibling);
            this._hasAttached = true;
        }
        return this._hasAttached;
    }
    /**
     * Waits for the zone to stabilize, then either focuses the first element that the
     * user specified, or the first tabbable element.
     * @return {?} Returns a promise that resolves with a boolean, depending
     * on whether focus was moved successfuly.
     */
    focusInitialElementWhenReady() {
        return new Promise(resolve => {
            this._executeOnStable(() => resolve(this.focusInitialElement()));
        });
    }
    /**
     * Waits for the zone to stabilize, then focuses
     * the first tabbable element within the focus trap region.
     * @return {?} Returns a promise that resolves with a boolean, depending
     * on whether focus was moved successfuly.
     */
    focusFirstTabbableElementWhenReady() {
        return new Promise(resolve => {
            this._executeOnStable(() => resolve(this.focusFirstTabbableElement()));
        });
    }
    /**
     * Waits for the zone to stabilize, then focuses
     * the last tabbable element within the focus trap region.
     * @return {?} Returns a promise that resolves with a boolean, depending
     * on whether focus was moved successfuly.
     */
    focusLastTabbableElementWhenReady() {
        return new Promise(resolve => {
            this._executeOnStable(() => resolve(this.focusLastTabbableElement()));
        });
    }
    /**
     * Get the specified boundary element of the trapped region.
     * @param {?} bound The boundary to get (start or end of trapped region).
     * @return {?} The boundary element.
     */
    _getRegionBoundary(bound) {
        /** @type {?} */
        let markers = /** @type {?} */ (this._element.querySelectorAll(`[cdk-focus-region-${bound}], ` +
            `[cdkFocusRegion${bound}], ` +
            `[cdk-focus-${bound}]`));
        for (let i = 0; i < markers.length; i++) {
            // @breaking-change 7.0.0
            if (markers[i].hasAttribute(`cdk-focus-${bound}`)) {
                console.warn(`Found use of deprecated attribute 'cdk-focus-${bound}', ` +
                    `use 'cdkFocusRegion${bound}' instead. The deprecated ` +
                    `attribute will be removed in 7.0.0.`, markers[i]);
            }
            else if (markers[i].hasAttribute(`cdk-focus-region-${bound}`)) {
                console.warn(`Found use of deprecated attribute 'cdk-focus-region-${bound}', ` +
                    `use 'cdkFocusRegion${bound}' instead. The deprecated attribute ` +
                    `will be removed in 7.0.0.`, markers[i]);
            }
        }
        if (bound == 'start') {
            return markers.length ? markers[0] : this._getFirstTabbableElement(this._element);
        }
        return markers.length ?
            markers[markers.length - 1] : this._getLastTabbableElement(this._element);
    }
    /**
     * Focuses the element that should be focused when the focus trap is initialized.
     * @return {?} Whether focus was moved successfuly.
     */
    focusInitialElement() {
        /** @type {?} */
        const redirectToElement = /** @type {?} */ (this._element.querySelector(`[cdk-focus-initial], ` +
            `[cdkFocusInitial]`));
        if (redirectToElement) {
            // @breaking-change 7.0.0
            if (redirectToElement.hasAttribute(`cdk-focus-initial`)) {
                console.warn(`Found use of deprecated attribute 'cdk-focus-initial', ` +
                    `use 'cdkFocusInitial' instead. The deprecated attribute ` +
                    `will be removed in 7.0.0`, redirectToElement);
            }
            redirectToElement.focus();
            return true;
        }
        return this.focusFirstTabbableElement();
    }
    /**
     * Focuses the first tabbable element within the focus trap region.
     * @return {?} Whether focus was moved successfuly.
     */
    focusFirstTabbableElement() {
        /** @type {?} */
        const redirectToElement = this._getRegionBoundary('start');
        if (redirectToElement) {
            redirectToElement.focus();
        }
        return !!redirectToElement;
    }
    /**
     * Focuses the last tabbable element within the focus trap region.
     * @return {?} Whether focus was moved successfuly.
     */
    focusLastTabbableElement() {
        /** @type {?} */
        const redirectToElement = this._getRegionBoundary('end');
        if (redirectToElement) {
            redirectToElement.focus();
        }
        return !!redirectToElement;
    }
    /**
     * Checks whether the focus trap has successfuly been attached.
     * @return {?}
     */
    hasAttached() {
        return this._hasAttached;
    }
    /**
     * Get the first tabbable element from a DOM subtree (inclusive).
     * @param {?} root
     * @return {?}
     */
    _getFirstTabbableElement(root) {
        if (this._checker.isFocusable(root) && this._checker.isTabbable(root)) {
            return root;
        }
        /** @type {?} */
        let children = root.children || root.childNodes;
        for (let i = 0; i < children.length; i++) {
            /** @type {?} */
            let tabbableChild = children[i].nodeType === this._document.ELEMENT_NODE ?
                this._getFirstTabbableElement(/** @type {?} */ (children[i])) :
                null;
            if (tabbableChild) {
                return tabbableChild;
            }
        }
        return null;
    }
    /**
     * Get the last tabbable element from a DOM subtree (inclusive).
     * @param {?} root
     * @return {?}
     */
    _getLastTabbableElement(root) {
        if (this._checker.isFocusable(root) && this._checker.isTabbable(root)) {
            return root;
        }
        /** @type {?} */
        let children = root.children || root.childNodes;
        for (let i = children.length - 1; i >= 0; i--) {
            /** @type {?} */
            let tabbableChild = children[i].nodeType === this._document.ELEMENT_NODE ?
                this._getLastTabbableElement(/** @type {?} */ (children[i])) :
                null;
            if (tabbableChild) {
                return tabbableChild;
            }
        }
        return null;
    }
    /**
     * Creates an anchor element.
     * @return {?}
     */
    _createAnchor() {
        /** @type {?} */
        const anchor = this._document.createElement('div');
        anchor.tabIndex = this._enabled ? 0 : -1;
        anchor.classList.add('cdk-visually-hidden');
        anchor.classList.add('cdk-focus-trap-anchor');
        return anchor;
    }
    /**
     * Executes a function when the zone is stable.
     * @param {?} fn
     * @return {?}
     */
    _executeOnStable(fn) {
        if (this._ngZone.isStable) {
            fn();
        }
        else {
            this._ngZone.onStable.asObservable().pipe(take(1)).subscribe(fn);
        }
    }
}
/**
 * Factory that allows easy instantiation of focus traps.
 */
class FocusTrapFactory {
    /**
     * @param {?} _checker
     * @param {?} _ngZone
     * @param {?} _document
     */
    constructor(_checker, _ngZone, _document) {
        this._checker = _checker;
        this._ngZone = _ngZone;
        this._document = _document;
    }
    /**
     * Creates a focus-trapped region around the given element.
     * @param {?} element The element around which focus will be trapped.
     * @param {?=} deferCaptureElements Defers the creation of focus-capturing elements to be done
     *     manually by the user.
     * @return {?} The created focus trap instance.
     */
    create(element, deferCaptureElements = false) {
        return new FocusTrap(element, this._checker, this._ngZone, this._document, deferCaptureElements);
    }
}
FocusTrapFactory.decorators = [
    { type: Injectable, args: [{ providedIn: 'root' },] },
];
/** @nocollapse */
FocusTrapFactory.ctorParameters = () => [
    { type: InteractivityChecker },
    { type: NgZone },
    { type: undefined, decorators: [{ type: Inject, args: [DOCUMENT,] }] }
];
/** @nocollapse */ FocusTrapFactory.ngInjectableDef = defineInjectable({ factory: function FocusTrapFactory_Factory() { return new FocusTrapFactory(inject(InteractivityChecker), inject(NgZone), inject(DOCUMENT)); }, token: FocusTrapFactory, providedIn: "root" });
/**
 * Directive for trapping focus within a region.
 */
class CdkTrapFocus {
    /**
     * @param {?} _elementRef
     * @param {?} _focusTrapFactory
     * @param {?} _document
     */
    constructor(_elementRef, _focusTrapFactory, _document) {
        this._elementRef = _elementRef;
        this._focusTrapFactory = _focusTrapFactory;
        /**
         * Previously focused element to restore focus to upon destroy when using autoCapture.
         */
        this._previouslyFocusedElement = null;
        this._document = _document;
        this.focusTrap = this._focusTrapFactory.create(this._elementRef.nativeElement, true);
    }
    /**
     * Whether the focus trap is active.
     * @return {?}
     */
    get enabled() { return this.focusTrap.enabled; }
    /**
     * @param {?} value
     * @return {?}
     */
    set enabled(value) { this.focusTrap.enabled = coerceBooleanProperty(value); }
    /**
     * Whether the directive should automatially move focus into the trapped region upon
     * initialization and return focus to the previous activeElement upon destruction.
     * @return {?}
     */
    get autoCapture() { return this._autoCapture; }
    /**
     * @param {?} value
     * @return {?}
     */
    set autoCapture(value) { this._autoCapture = coerceBooleanProperty(value); }
    /**
     * @return {?}
     */
    ngOnDestroy() {
        this.focusTrap.destroy();
        // If we stored a previously focused element when using autoCapture, return focus to that
        // element now that the trapped region is being destroyed.
        if (this._previouslyFocusedElement) {
            this._previouslyFocusedElement.focus();
            this._previouslyFocusedElement = null;
        }
    }
    /**
     * @return {?}
     */
    ngAfterContentInit() {
        this.focusTrap.attachAnchors();
        if (this.autoCapture) {
            this._previouslyFocusedElement = /** @type {?} */ (this._document.activeElement);
            this.focusTrap.focusInitialElementWhenReady();
        }
    }
    /**
     * @return {?}
     */
    ngDoCheck() {
        if (!this.focusTrap.hasAttached()) {
            this.focusTrap.attachAnchors();
        }
    }
}
CdkTrapFocus.decorators = [
    { type: Directive, args: [{
                selector: '[cdkTrapFocus]',
                exportAs: 'cdkTrapFocus',
            },] },
];
/** @nocollapse */
CdkTrapFocus.ctorParameters = () => [
    { type: ElementRef },
    { type: FocusTrapFactory },
    { type: undefined, decorators: [{ type: Inject, args: [DOCUMENT,] }] }
];
CdkTrapFocus.propDecorators = {
    enabled: [{ type: Input, args: ['cdkTrapFocus',] }],
    autoCapture: [{ type: Input, args: ['cdkTrapFocusAutoCapture',] }]
};

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/** @type {?} */
const LIVE_ANNOUNCER_ELEMENT_TOKEN = new InjectionToken('liveAnnouncerElement', {
    providedIn: 'root',
    factory: LIVE_ANNOUNCER_ELEMENT_TOKEN_FACTORY,
});
/**
 * \@docs-private
 * @return {?}
 */
function LIVE_ANNOUNCER_ELEMENT_TOKEN_FACTORY() {
    return null;
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
class LiveAnnouncer {
    /**
     * @param {?} elementToken
     * @param {?} _document
     */
    constructor(elementToken, _document) {
        // We inject the live element and document as `any` because the constructor signature cannot
        // reference browser globals (HTMLElement, Document) on non-browser environments, since having
        // a class decorator causes TypeScript to preserve the constructor signature types.
        this._document = _document;
        this._liveElement = elementToken || this._createLiveElement();
    }
    /**
     * Announces a message to screenreaders.
     * @param {?} message Message to be announced to the screenreader
     * @param {?=} politeness The politeness of the announcer element
     * @return {?} Promise that will be resolved when the message is added to the DOM.
     */
    announce(message, politeness = 'polite') {
        this._liveElement.textContent = '';
        // TODO: ensure changing the politeness works on all environments we support.
        this._liveElement.setAttribute('aria-live', politeness);
        // This 100ms timeout is necessary for some browser + screen-reader combinations:
        // - Both JAWS and NVDA over IE11 will not announce anything without a non-zero timeout.
        // - With Chrome and IE11 with NVDA or JAWS, a repeated (identical) message won't be read a
        //   second time without clearing and then using a non-zero delay.
        // (using JAWS 17 at time of this writing).
        return new Promise(resolve => {
            setTimeout(() => {
                this._liveElement.textContent = message;
                resolve();
            }, 100);
        });
    }
    /**
     * @return {?}
     */
    ngOnDestroy() {
        if (this._liveElement && this._liveElement.parentNode) {
            this._liveElement.parentNode.removeChild(this._liveElement);
        }
    }
    /**
     * @return {?}
     */
    _createLiveElement() {
        /** @type {?} */
        const elementClass = 'cdk-live-announcer-element';
        /** @type {?} */
        const previousElements = this._document.getElementsByClassName(elementClass);
        // Remove any old containers. This can happen when coming in from a server-side-rendered page.
        for (let i = 0; i < previousElements.length; i++) {
            /** @type {?} */ ((previousElements[i].parentNode)).removeChild(previousElements[i]);
        }
        /** @type {?} */
        const liveEl = this._document.createElement('div');
        liveEl.classList.add(elementClass);
        liveEl.classList.add('cdk-visually-hidden');
        liveEl.setAttribute('aria-atomic', 'true');
        liveEl.setAttribute('aria-live', 'polite');
        this._document.body.appendChild(liveEl);
        return liveEl;
    }
}
LiveAnnouncer.decorators = [
    { type: Injectable, args: [{ providedIn: 'root' },] },
];
/** @nocollapse */
LiveAnnouncer.ctorParameters = () => [
    { type: undefined, decorators: [{ type: Optional }, { type: Inject, args: [LIVE_ANNOUNCER_ELEMENT_TOKEN,] }] },
    { type: undefined, decorators: [{ type: Inject, args: [DOCUMENT,] }] }
];
/** @nocollapse */ LiveAnnouncer.ngInjectableDef = defineInjectable({ factory: function LiveAnnouncer_Factory() { return new LiveAnnouncer(inject(LIVE_ANNOUNCER_ELEMENT_TOKEN, 8), inject(DOCUMENT)); }, token: LiveAnnouncer, providedIn: "root" });
/**
 * A directive that works similarly to aria-live, but uses the LiveAnnouncer to ensure compatibility
 * with a wider range of browsers and screen readers.
 */
class CdkAriaLive {
    /**
     * @param {?} _elementRef
     * @param {?} _liveAnnouncer
     * @param {?} _contentObserver
     * @param {?} _ngZone
     */
    constructor(_elementRef, _liveAnnouncer, _contentObserver, _ngZone) {
        this._elementRef = _elementRef;
        this._liveAnnouncer = _liveAnnouncer;
        this._contentObserver = _contentObserver;
        this._ngZone = _ngZone;
        this._politeness = 'off';
    }
    /**
     * The aria-live politeness level to use when announcing messages.
     * @return {?}
     */
    get politeness() { return this._politeness; }
    /**
     * @param {?} value
     * @return {?}
     */
    set politeness(value) {
        this._politeness = value === 'polite' || value === 'assertive' ? value : 'off';
        if (this._politeness === 'off') {
            if (this._subscription) {
                this._subscription.unsubscribe();
                this._subscription = null;
            }
        }
        else if (!this._subscription) {
            this._subscription = this._ngZone.runOutsideAngular(() => {
                return this._contentObserver
                    .observe(this._elementRef)
                    .subscribe(() => {
                    /** @type {?} */
                    const element = this._elementRef.nativeElement;
                    this._liveAnnouncer.announce(element.textContent, this._politeness);
                });
            });
        }
    }
    /**
     * @return {?}
     */
    ngOnDestroy() {
        if (this._subscription) {
            this._subscription.unsubscribe();
        }
    }
}
CdkAriaLive.decorators = [
    { type: Directive, args: [{
                selector: '[cdkAriaLive]',
                exportAs: 'cdkAriaLive',
            },] },
];
/** @nocollapse */
CdkAriaLive.ctorParameters = () => [
    { type: ElementRef },
    { type: LiveAnnouncer },
    { type: ContentObserver },
    { type: NgZone }
];
CdkAriaLive.propDecorators = {
    politeness: [{ type: Input, args: ['cdkAriaLive',] }]
};
/**
 * \@docs-private \@deprecated \@breaking-change 7.0.0
 * @param {?} parentDispatcher
 * @param {?} liveElement
 * @param {?} _document
 * @return {?}
 */
function LIVE_ANNOUNCER_PROVIDER_FACTORY(parentDispatcher, liveElement, _document) {
    return parentDispatcher || new LiveAnnouncer(liveElement, _document);
}
/** *
 * \@docs-private \@deprecated \@breaking-change 7.0.0
  @type {?} */
const LIVE_ANNOUNCER_PROVIDER = {
    // If there is already a LiveAnnouncer available, use that. Otherwise, provide a new one.
    provide: LiveAnnouncer,
    deps: [
        [new Optional(), new SkipSelf(), LiveAnnouncer],
        [new Optional(), new Inject(LIVE_ANNOUNCER_ELEMENT_TOKEN)],
        DOCUMENT,
    ],
    useFactory: LIVE_ANNOUNCER_PROVIDER_FACTORY
};

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
/** @type {?} */
const TOUCH_BUFFER_MS = 650;
/**
 * Monitors mouse and keyboard events to determine the cause of focus events.
 */
class FocusMonitor {
    /**
     * @param {?} _ngZone
     * @param {?} _platform
     */
    constructor(_ngZone, _platform) {
        this._ngZone = _ngZone;
        this._platform = _platform;
        /**
         * The focus origin that the next focus event is a result of.
         */
        this._origin = null;
        /**
         * Whether the window has just been focused.
         */
        this._windowFocused = false;
        /**
         * Map of elements being monitored to their info.
         */
        this._elementInfo = new Map();
        /**
         * A map of global objects to lists of current listeners.
         */
        this._unregisterGlobalListeners = () => { };
        /**
         * The number of elements currently being monitored.
         */
        this._monitoredElementCount = 0;
    }
    /**
     * @param {?} element
     * @param {?=} checkChildren
     * @return {?}
     */
    monitor(element, checkChildren = false) {
        // Do nothing if we're not on the browser platform.
        if (!this._platform.isBrowser) {
            return of(null);
        }
        /** @type {?} */
        const nativeElement = this._getNativeElement(element);
        // Check if we're already monitoring this element.
        if (this._elementInfo.has(nativeElement)) {
            /** @type {?} */
            let cachedInfo = this._elementInfo.get(nativeElement); /** @type {?} */
            ((cachedInfo)).checkChildren = checkChildren;
            return /** @type {?} */ ((cachedInfo)).subject.asObservable();
        }
        /** @type {?} */
        let info = {
            unlisten: () => { },
            checkChildren: checkChildren,
            subject: new Subject()
        };
        this._elementInfo.set(nativeElement, info);
        this._incrementMonitoredElementCount();
        /** @type {?} */
        let focusListener = (event) => this._onFocus(event, nativeElement);
        /** @type {?} */
        let blurListener = (event) => this._onBlur(event, nativeElement);
        this._ngZone.runOutsideAngular(() => {
            nativeElement.addEventListener('focus', focusListener, true);
            nativeElement.addEventListener('blur', blurListener, true);
        });
        // Create an unlisten function for later.
        info.unlisten = () => {
            nativeElement.removeEventListener('focus', focusListener, true);
            nativeElement.removeEventListener('blur', blurListener, true);
        };
        return info.subject.asObservable();
    }
    /**
     * @param {?} element
     * @return {?}
     */
    stopMonitoring(element) {
        /** @type {?} */
        const nativeElement = this._getNativeElement(element);
        /** @type {?} */
        const elementInfo = this._elementInfo.get(nativeElement);
        if (elementInfo) {
            elementInfo.unlisten();
            elementInfo.subject.complete();
            this._setClasses(nativeElement);
            this._elementInfo.delete(nativeElement);
            this._decrementMonitoredElementCount();
        }
    }
    /**
     * Focuses the element via the specified focus origin.
     * @param {?} element Element to focus.
     * @param {?} origin Focus origin.
     * @param {?=} options Options that can be used to configure the focus behavior.
     * @return {?}
     */
    focusVia(element, origin, options) {
        this._setOriginForCurrentEventQueue(origin);
        // `focus` isn't available on the server
        if (typeof element.focus === 'function') {
            // Cast the element to `any`, because the TS typings don't have the `options` parameter yet.
            (/** @type {?} */ (element)).focus(options);
        }
    }
    /**
     * @return {?}
     */
    ngOnDestroy() {
        this._elementInfo.forEach((_info, element) => this.stopMonitoring(element));
    }
    /**
     * Register necessary event listeners on the document and window.
     * @return {?}
     */
    _registerGlobalListeners() {
        // Do nothing if we're not on the browser platform.
        if (!this._platform.isBrowser) {
            return;
        }
        /** @type {?} */
        let documentKeydownListener = () => {
            this._lastTouchTarget = null;
            this._setOriginForCurrentEventQueue('keyboard');
        };
        /** @type {?} */
        let documentMousedownListener = () => {
            if (!this._lastTouchTarget) {
                this._setOriginForCurrentEventQueue('mouse');
            }
        };
        /** @type {?} */
        let documentTouchstartListener = (event) => {
            if (this._touchTimeoutId != null) {
                clearTimeout(this._touchTimeoutId);
            }
            this._lastTouchTarget = event.target;
            this._touchTimeoutId = setTimeout(() => this._lastTouchTarget = null, TOUCH_BUFFER_MS);
        };
        /** @type {?} */
        let windowFocusListener = () => {
            this._windowFocused = true;
            this._windowFocusTimeoutId = setTimeout(() => this._windowFocused = false);
        };
        // Note: we listen to events in the capture phase so we can detect them even if the user stops
        // propagation.
        this._ngZone.runOutsideAngular(() => {
            document.addEventListener('keydown', documentKeydownListener, true);
            document.addEventListener('mousedown', documentMousedownListener, true);
            document.addEventListener('touchstart', documentTouchstartListener, supportsPassiveEventListeners() ? (/** @type {?} */ ({ passive: true, capture: true })) : true);
            window.addEventListener('focus', windowFocusListener);
        });
        this._unregisterGlobalListeners = () => {
            document.removeEventListener('keydown', documentKeydownListener, true);
            document.removeEventListener('mousedown', documentMousedownListener, true);
            document.removeEventListener('touchstart', documentTouchstartListener, supportsPassiveEventListeners() ? (/** @type {?} */ ({ passive: true, capture: true })) : true);
            window.removeEventListener('focus', windowFocusListener);
            // Clear timeouts for all potentially pending timeouts to prevent the leaks.
            clearTimeout(this._windowFocusTimeoutId);
            clearTimeout(this._touchTimeoutId);
            clearTimeout(this._originTimeoutId);
        };
    }
    /**
     * @param {?} element
     * @param {?} className
     * @param {?} shouldSet
     * @return {?}
     */
    _toggleClass(element, className, shouldSet) {
        if (shouldSet) {
            element.classList.add(className);
        }
        else {
            element.classList.remove(className);
        }
    }
    /**
     * Sets the focus classes on the element based on the given focus origin.
     * @param {?} element The element to update the classes on.
     * @param {?=} origin The focus origin.
     * @return {?}
     */
    _setClasses(element, origin) {
        /** @type {?} */
        const elementInfo = this._elementInfo.get(element);
        if (elementInfo) {
            this._toggleClass(element, 'cdk-focused', !!origin);
            this._toggleClass(element, 'cdk-touch-focused', origin === 'touch');
            this._toggleClass(element, 'cdk-keyboard-focused', origin === 'keyboard');
            this._toggleClass(element, 'cdk-mouse-focused', origin === 'mouse');
            this._toggleClass(element, 'cdk-program-focused', origin === 'program');
        }
    }
    /**
     * Sets the origin and schedules an async function to clear it at the end of the event queue.
     * @param {?} origin The origin to set.
     * @return {?}
     */
    _setOriginForCurrentEventQueue(origin) {
        this._ngZone.runOutsideAngular(() => {
            this._origin = origin;
            // Sometimes the focus origin won't be valid in Firefox because Firefox seems to focus *one*
            // tick after the interaction event fired. To ensure the focus origin is always correct,
            // the focus origin will be determined at the beginning of the next tick.
            this._originTimeoutId = setTimeout(() => this._origin = null, 1);
        });
    }
    /**
     * Checks whether the given focus event was caused by a touchstart event.
     * @param {?} event The focus event to check.
     * @return {?} Whether the event was caused by a touch.
     */
    _wasCausedByTouch(event) {
        /** @type {?} */
        let focusTarget = event.target;
        return this._lastTouchTarget instanceof Node && focusTarget instanceof Node &&
            (focusTarget === this._lastTouchTarget || focusTarget.contains(this._lastTouchTarget));
    }
    /**
     * Handles focus events on a registered element.
     * @param {?} event The focus event.
     * @param {?} element The monitored element.
     * @return {?}
     */
    _onFocus(event, element) {
        /** @type {?} */
        const elementInfo = this._elementInfo.get(element);
        if (!elementInfo || (!elementInfo.checkChildren && element !== event.target)) {
            return;
        }
        /** @type {?} */
        let origin = this._origin;
        if (!origin) {
            if (this._windowFocused && this._lastFocusOrigin) {
                origin = this._lastFocusOrigin;
            }
            else if (this._wasCausedByTouch(event)) {
                origin = 'touch';
            }
            else {
                origin = 'program';
            }
        }
        this._setClasses(element, origin);
        this._emitOrigin(elementInfo.subject, origin);
        this._lastFocusOrigin = origin;
    }
    /**
     * Handles blur events on a registered element.
     * @param {?} event The blur event.
     * @param {?} element The monitored element.
     * @return {?}
     */
    _onBlur(event, element) {
        /** @type {?} */
        const elementInfo = this._elementInfo.get(element);
        if (!elementInfo || (elementInfo.checkChildren && event.relatedTarget instanceof Node &&
            element.contains(event.relatedTarget))) {
            return;
        }
        this._setClasses(element);
        this._emitOrigin(elementInfo.subject, null);
    }
    /**
     * @param {?} subject
     * @param {?} origin
     * @return {?}
     */
    _emitOrigin(subject, origin) {
        this._ngZone.run(() => subject.next(origin));
    }
    /**
     * @return {?}
     */
    _incrementMonitoredElementCount() {
        // Register global listeners when first element is monitored.
        if (++this._monitoredElementCount == 1) {
            this._registerGlobalListeners();
        }
    }
    /**
     * @return {?}
     */
    _decrementMonitoredElementCount() {
        // Unregister global listeners when last element is unmonitored.
        if (!--this._monitoredElementCount) {
            this._unregisterGlobalListeners();
            this._unregisterGlobalListeners = () => { };
        }
    }
    /**
     * @param {?} element
     * @return {?}
     */
    _getNativeElement(element) {
        return element instanceof ElementRef ? element.nativeElement : element;
    }
}
FocusMonitor.decorators = [
    { type: Injectable, args: [{ providedIn: 'root' },] },
];
/** @nocollapse */
FocusMonitor.ctorParameters = () => [
    { type: NgZone },
    { type: Platform }
];
/** @nocollapse */ FocusMonitor.ngInjectableDef = defineInjectable({ factory: function FocusMonitor_Factory() { return new FocusMonitor(inject(NgZone), inject(Platform)); }, token: FocusMonitor, providedIn: "root" });
/**
 * Directive that determines how a particular element was focused (via keyboard, mouse, touch, or
 * programmatically) and adds corresponding classes to the element.
 *
 * There are two variants of this directive:
 * 1) cdkMonitorElementFocus: does not consider an element to be focused if one of its children is
 *    focused.
 * 2) cdkMonitorSubtreeFocus: considers an element focused if it or any of its children are focused.
 */
class CdkMonitorFocus {
    /**
     * @param {?} _elementRef
     * @param {?} _focusMonitor
     */
    constructor(_elementRef, _focusMonitor) {
        this._elementRef = _elementRef;
        this._focusMonitor = _focusMonitor;
        this.cdkFocusChange = new EventEmitter();
        this._monitorSubscription = this._focusMonitor.monitor(this._elementRef, this._elementRef.nativeElement.hasAttribute('cdkMonitorSubtreeFocus'))
            .subscribe(origin => this.cdkFocusChange.emit(origin));
    }
    /**
     * @return {?}
     */
    ngOnDestroy() {
        this._focusMonitor.stopMonitoring(this._elementRef);
        this._monitorSubscription.unsubscribe();
    }
}
CdkMonitorFocus.decorators = [
    { type: Directive, args: [{
                selector: '[cdkMonitorElementFocus], [cdkMonitorSubtreeFocus]',
            },] },
];
/** @nocollapse */
CdkMonitorFocus.ctorParameters = () => [
    { type: ElementRef },
    { type: FocusMonitor }
];
CdkMonitorFocus.propDecorators = {
    cdkFocusChange: [{ type: Output }]
};
/**
 * \@docs-private \@deprecated \@breaking-change 7.0.0
 * @param {?} parentDispatcher
 * @param {?} ngZone
 * @param {?} platform
 * @return {?}
 */
function FOCUS_MONITOR_PROVIDER_FACTORY(parentDispatcher, ngZone, platform) {
    return parentDispatcher || new FocusMonitor(ngZone, platform);
}
/** *
 * \@docs-private \@deprecated \@breaking-change 7.0.0
  @type {?} */
const FOCUS_MONITOR_PROVIDER = {
    // If there is already a FocusMonitor available, use that. Otherwise, provide a new one.
    provide: FocusMonitor,
    deps: [[new Optional(), new SkipSelf(), FocusMonitor], NgZone, Platform],
    useFactory: FOCUS_MONITOR_PROVIDER_FACTORY
};

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */

/**
 * Screenreaders will often fire fake mousedown events when a focusable element
 * is activated using the keyboard. We can typically distinguish between these faked
 * mousedown events and real mousedown events using the "buttons" property. While
 * real mousedowns will indicate the mouse button that was pressed (e.g. "1" for
 * the left mouse button), faked mousedowns will usually set the property value to 0.
 * @param {?} event
 * @return {?}
 */
function isFakeMousedownFromScreenReader(event) {
    return event.buttons === 0;
}

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */
class A11yModule {
}
A11yModule.decorators = [
    { type: NgModule, args: [{
                imports: [CommonModule, PlatformModule, ObserversModule],
                declarations: [CdkAriaLive, CdkTrapFocus, CdkMonitorFocus],
                exports: [CdkAriaLive, CdkTrapFocus, CdkMonitorFocus],
            },] },
];

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */

/**
 * @fileoverview added by tsickle
 * @suppress {checkTypes,extraRequire,uselessCode} checked by tsc
 */

export { ARIA_DESCRIBER_PROVIDER_FACTORY, MESSAGES_CONTAINER_ID, CDK_DESCRIBEDBY_ID_PREFIX, CDK_DESCRIBEDBY_HOST_ATTRIBUTE, AriaDescriber, ARIA_DESCRIBER_PROVIDER, ActiveDescendantKeyManager, FocusKeyManager, ListKeyManager, FocusTrap, FocusTrapFactory, CdkTrapFocus, InteractivityChecker, LIVE_ANNOUNCER_PROVIDER_FACTORY, LiveAnnouncer, CdkAriaLive, LIVE_ANNOUNCER_PROVIDER, LIVE_ANNOUNCER_ELEMENT_TOKEN_FACTORY, LIVE_ANNOUNCER_ELEMENT_TOKEN, FOCUS_MONITOR_PROVIDER_FACTORY, TOUCH_BUFFER_MS, FocusMonitor, CdkMonitorFocus, FOCUS_MONITOR_PROVIDER, isFakeMousedownFromScreenReader, A11yModule };
//# sourceMappingURL=a11y.js.map
