ckeditor/ckeditor5-utils

/**
 * @license Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
 */

/* globals navigator:false */

/**
 * @module utils/env
 */

const userAgent = navigator.userAgent.toLowerCase();

/**
 * A namespace containing environment and browser information.
 *
 * @namespace
 */
const env = {
    /**
     * Indicates that the application is running on Macintosh.
     *
     * @static
     * @type {Boolean}
     */
    isMac: isMac( userAgent ),

    /**
     * Indicates that the application is running in Firefox (Gecko).
     *
     * @static
     * @type {Boolean}
     */
    isGecko: isGecko( userAgent ),

    /**
     * Indicates that the application is running in Safari.
     *
     * @static
     * @type {Boolean}
     */
    isSafari: isSafari( userAgent ),

    /**
     * Indicates that the application is running on Android mobile device.
     *
     * @static
     * @type {Boolean}
     */
    isAndroid: isAndroid( userAgent ),

    /**
     * Environment features information.
     *
     * @memberOf module:utils/env~env
     * @namespace
     */
    features: {
        /**
         * Indicates that the environment supports ES2018 Unicode property escapes — like `\p{P}` or `\p{L}`.
         * More information about unicode properties might be found
         * [in Unicode Standard Annex #44](https://www.unicode.org/reports/tr44/#GC_Values_Table).
         *
         * @type {Boolean}
         */
        isRegExpUnicodePropertySupported: isRegExpUnicodePropertySupported()
    }
};

export default env;

/**
 * Checks if User Agent represented by the string is running on Macintosh.
 *
 * @param {String} userAgent **Lowercase** `navigator.userAgent` string.
 * @returns {Boolean} Whether User Agent is running on Macintosh or not.
 */
export function isMac( userAgent ) {
    return userAgent.indexOf( 'macintosh' ) > -1;
}

/**
 * Checks if User Agent represented by the string is Firefox (Gecko).
 *
 * @param {String} userAgent **Lowercase** `navigator.userAgent` string.
 * @returns {Boolean} Whether User Agent is Firefox or not.
 */
export function isGecko( userAgent ) {
    return !!userAgent.match( /gecko\/\d+/ );
}

/**
 * Checks if User Agent represented by the string is Safari.
 *
 * @param {String} userAgent **Lowercase** `navigator.userAgent` string.
 * @returns {Boolean} Whether User Agent is Safari or not.
 */
export function isSafari( userAgent ) {
    return userAgent.indexOf( ' applewebkit/' ) > -1 && userAgent.indexOf( 'chrome' ) === -1;
}

/**
 * Checks if User Agent represented by the string is Android mobile device.
 *
 * @param {String} userAgent **Lowercase** `navigator.userAgent` string.
 * @returns {Boolean} Whether User Agent is Safari or not.
 */
export function isAndroid( userAgent ) {
    return userAgent.indexOf( 'android' ) > -1;
}

/**
 * Checks if the current environment supports ES2018 Unicode properties like `\p{P}` or `\p{L}`.
 * More information about unicode properties might be found
 * [in Unicode Standard Annex #44](https://www.unicode.org/reports/tr44/#GC_Values_Table).
 *
 * @returns {Boolean}
 */
export function isRegExpUnicodePropertySupported() {
    let isSupported = false;

    // Feature detection for Unicode properties. Added in ES2018. Currently Firefox does not support it.
    // See https://github.com/ckeditor/ckeditor5-mention/issues/44#issuecomment-487002174.

    try {
        // Usage of regular expression literal cause error during build (ckeditor/ckeditor5-dev#534).
        isSupported = 'ć'.search( new RegExp( '[\\p{L}]', 'u' ) ) === 0;
    } catch ( error ) {
        // Firefox throws a SyntaxError when the group is unsupported.
    }

    return isSupported;
}