// Copyright (c) 2015 Spinpunch, Inc. All Rights Reserved.
// See License.txt for license information.

var AppDispatcher = require('../dispatcher/app_dispatcher.jsx');
var ChannelStore = require('../stores/channel_store.jsx');
var UserStore = require('../stores/user_store.jsx');
var TeamStore = require('../stores/team_store.jsx');
var Constants = require('../utils/constants.jsx');
var ActionTypes = Constants.ActionTypes;
var AsyncClient = require('./async_client.jsx');
var client = require('./client.jsx');
var Autolinker = require('autolinker');

export function isEmail(email) {
    var regex = /^([a-zA-Z0-9_.+-])+\@(([a-zA-Z0-9-])+\.)+([a-zA-Z0-9]{2,4})+$/;
    return regex.test(email);
}

export function cleanUpUrlable(input) {
    var cleaned = input.trim().replace(/-/g, ' ').replace(/[^\w\s]/gi, '').toLowerCase().replace(/\s/g, '-');
    cleaned = cleaned.replace(/^\-+/, '');
    cleaned = cleaned.replace(/\-+$/, '');
    return cleaned;
}

export function isTestDomain() {
    if ((/^localhost/).test(window.location.hostname)) {
        return true;
    }

    if ((/^dockerhost/).test(window.location.hostname)) {
        return true;
    }

    if ((/^test/).test(window.location.hostname)) {
        return true;
    }

    if ((/^127.0./).test(window.location.hostname)) {
        return true;
    }

    if ((/^192.168./).test(window.location.hostname)) {
        return true;
    }

    if ((/^10./).test(window.location.hostname)) {
        return true;
    }

    if ((/^176./).test(window.location.hostname)) {
        return true;
    }

    return false;
}

export function isInRole(roles, inRole) {
    var parts = roles.split(' ');
    for (var i = 0; i < parts.length; i++) {
        if (parts[i] === inRole) {
            return true;
        }
    }

    return false;
}

export function isAdmin(roles) {
    if (isInRole(roles, 'admin')) {
        return true;
    }

    if (isInRole(roles, 'system_admin')) {
        return true;
    }

    return false;
}

export function getDomainWithOutSub() {
    var parts = window.location.host.split('.');

    if (parts.length === 1) {
        if (parts[0].indexOf('dockerhost') > -1) {
            return 'dockerhost:8065';
        }

        return 'localhost:8065';
    }

    return parts[1] + '.' + parts[2];
}

export function getCookie(name) {
    var value = '; ' + document.cookie;
    var parts = value.split('; ' + name + '=');
    if (parts.length === 2) {
        return parts.pop().split(';').shift();
    }
}

export function notifyMe(title, body, channel) {
    if ('Notification' in window && Notification.permission !== 'denied') {
        Notification.requestPermission(function onRequestPermission(permission) {
            if (Notification.permission !== permission) {
                Notification.permission = permission;
            }

            if (permission === 'granted') {
                var notification = new Notification(title, {body: body, tag: body, icon: '/static/images/icon50x50.gif'});
                notification.onclick = function onClick() {
                    window.focus();
                    if (channel) {
                        switchChannel(channel);
                    } else {
                        window.location.href = TeamStore.getCurrentTeamUrl() + '/channels/town-square';
                    }
                };
                setTimeout(function closeNotificationOnTimeout() {
                    notification.close();
                }, 5000);
            }
        });
    }
}

export function ding() {
    if (!isBrowserFirefox()) {
        var audio = new Audio('/static/images/ding.mp3');
        audio.play();
    }
}

export function getUrlParameter(sParam) {
    var sPageURL = window.location.search.substring(1);
    var sURLVariables = sPageURL.split('&');
    for (var i = 0; i < sURLVariables.length; i++) {
        var sParameterName = sURLVariables[i].split('=');
        if (sParameterName[0] === sParam) {
            return sParameterName[1];
        }
    }
    return null;
}

export function getDateForUnixTicks(ticks) {
    return new Date(ticks);
}

export function displayDate(ticks) {
    var d = new Date(ticks);
    var monthNames = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];

    return monthNames[d.getMonth()] + ' ' + d.getDate() + ', ' + d.getFullYear();
}

export function displayTime(ticks) {
    var d = new Date(ticks);
    var hours = d.getHours();
    var minutes = d.getMinutes();

    var ampm = 'AM';
    if (hours >= 12) {
        ampm = 'PM';
    }

    hours = hours % 12;
    if (!hours) {
        hours = '12';
    }
    if (minutes <= 9) {
        minutes = '0' + minutes;
    }
    return hours + ':' + minutes + ' ' + ampm;
}

export function displayDateTime(ticks) {
    var seconds = Math.floor((Date.now() - ticks) / 1000);

    var interval = Math.floor(seconds / 3600);

    if (interval > 24) {
        return this.displayTime(ticks);
    }

    if (interval > 1) {
        return interval + ' hours ago';
    }

    if (interval === 1) {
        return interval + ' hour ago';
    }

    interval = Math.floor(seconds / 60);
    if (interval > 1) {
        return interval + ' minutes ago';
    }

    return '1 minute ago';
}

export function displayCommentDateTime(ticks) {
    return displayDate(ticks) + ' ' + displayTime(ticks);
}

// returns Unix timestamp in milliseconds
export function getTimestamp() {
    return Date.now();
}

function testUrlMatch(text) {
    var urlMatcher = new Autolinker.matchParser.MatchParser({
        urls: true,
        emails: false,
        twitter: false,
        phone: false,
        hashtag: false
    });
    var result = [];
    function replaceFn(match) {
        var linkData = {};
        var matchText = match.getMatchedText();

        linkData.text = matchText;
        if (matchText.trim().indexOf('http') !== 0) {
            linkData.link = 'http://' + matchText;
        } else {
            linkData.link = matchText;
        }

        result.push(linkData);
    }
    urlMatcher.replace(text, replaceFn, this);
    return result;
}

export function extractLinks(text) {
    var repRegex = new RegExp('<br>', 'g');
    var matches = testUrlMatch(text.replace(repRegex, '\n'));

    if (!matches.length) {
        return {links: null, text: text};
    }

    var links = [];
    for (var i = 0; i < matches.length; i++) {
        links.push(matches[i].link);
    }

    return {links: links, text: text};
}

export function escapeRegExp(string) {
    return string.replace(/([.*+?^=!:${}()|\[\]\/\\])/g, '\\$1');
}

function handleYoutubeTime(link) {
    var timeRegex = /[\\?&]t=([0-9hms]+)/;

    var time = link.trim().match(timeRegex);
    if (!time || !time[1]) {
        return '';
    }

    var hours = time[1].match(/([0-9]+)h/);
    var minutes = time[1].match(/([0-9]+)m/);
    var seconds = time[1].match(/([0-9]+)s/);

    var ticks = 0;

    if (hours && hours[1]) {
        ticks += parseInt(hours[1], 10) * 3600;
    }

    if (minutes && minutes[1]) {
        ticks += parseInt(minutes[1], 10) * 60;
    }

    if (seconds && seconds[1]) {
        ticks += parseInt(seconds[1], 10);
    }

    return '&start=' + ticks.toString();
}

function getYoutubeEmbed(link) {
    var regex = /.*(?:youtu.be\/|v\/|u\/\w\/|embed\/|watch\?v=|watch\?(?:[a-zA-Z-_]+=[a-zA-Z0-9-_]+&)+v=)([^#\&\?]*).*/;

    var youtubeId = link.trim().match(regex)[1];
    var time = handleYoutubeTime(link);

    function onClick(e) {
        var div = $(e.target).closest('.video-thumbnail__container')[0];
        var iframe = document.createElement('iframe');
        iframe.setAttribute('src',
                            'https://www.youtube.com/embed/' +
                            div.id +
                            '?autoplay=1&autohide=1&border=0&wmode=opaque&fs=1&enablejsapi=1' +
                            time);
        iframe.setAttribute('width', '480px');
        iframe.setAttribute('height', '360px');
        iframe.setAttribute('type', 'text/html');
        iframe.setAttribute('frameborder', '0');
        iframe.setAttribute('allowfullscreen', 'allowfullscreen');

        div.parentNode.replaceChild(iframe, div);
    }

    function success(data) {
        if (!data.items.length || !data.items[0].snippet) {
            return;
        }
        var metadata = data.items[0].snippet;
        $('.video-type.' + youtubeId).html('Youtube - ');
        $('.video-uploader.' + youtubeId).html(metadata.channelTitle);
        $('.video-title.' + youtubeId).find('a').html(metadata.title);
    }

    if (global.window.config.GoogleDeveloperKey) {
        $.ajax({
            async: true,
            url: 'https://www.googleapis.com/youtube/v3/videos',
            type: 'GET',
            data: {part: 'snippet', id: youtubeId, key: global.window.config.GoogleDeveloperKey},
            success: success
        });
    }

    return (
        <div className='post-comment'>
            <h4>
                <span className={'video-type ' + youtubeId}>YouTube</span>
                <span className={'video-title ' + youtubeId}><a href={link}></a></span>
            </h4>
            <h4 className={'video-uploader ' + youtubeId}></h4>
            <div
                className='video-div embed-responsive-item'
                id={youtubeId}
                onClick={onClick}
            >
                <div className='embed-responsive embed-responsive-4by3 video-div__placeholder'>
                    <div
                        id={youtubeId}
                        className='video-thumbnail__container'
                    >
                        <img
                            className='video-thumbnail'
                            src={'https://i.ytimg.com/vi/' + youtubeId + '/hqdefault.jpg'}
                        />
                        <div className='block'>
                            <span className='play-button'><span/></span>
                        </div>
                    </div>
                </div>
            </div>
        </div>
    );
}

export function getEmbed(link) {
    var ytRegex = /.*(?:youtu.be\/|v\/|u\/\w\/|embed\/|watch\?v=|watch\?(?:[a-zA-Z-_]+=[a-zA-Z0-9-_]+&)+v=)([^#\&\?]*).*/;

    var match = link.trim().match(ytRegex);
    if (match && match[1].length === 11) {
        return getYoutubeEmbed(link);
    }

    // Generl embed feature turned off for now
    return '';

    // NEEDS REFACTORING WHEN TURNED BACK ON
    /*
    var id = parseInt((Math.random() * 1000000) + 1);

    $.ajax({
        type: 'GET',
        url: 'https://query.yahooapis.com/v1/public/yql',
        data: {
            q: 'select * from html where url="' + link + "\" and xpath='html/head'",
            format: 'json'
        },
        async: true
    }).done(function(data) {
        if(!data.query.results) {
            return;
        }

        var headerData = data.query.results.head;

        var description = ''
        for(var i = 0; i < headerData.meta.length; i++) {
            if(headerData.meta[i].name && (headerData.meta[i].name === 'description' || headerData.meta[i].name === 'Description')){
                description = headerData.meta[i].content;
                break;
            }
        }

        $('.embed-title.'+id).html(headerData.title);
        $('.embed-description.'+id).html(description);
    })

    return (
        <div className='post-comment'>
            <div className={'web-embed-data'}>
                <p className={'embed-title ' + id} />
                <p className={'embed-description ' + id} />
                <p className={'embed-link ' + id}>{link}</p>
            </div>
        </div>
    );
    */
}

export function areStatesEqual(state1, state2) {
    return JSON.stringify(state1) === JSON.stringify(state2);
}

export function replaceHtmlEntities(text) {
    var tagsToReplace = {
        '&amp;': '&',
        '&lt;': '<',
        '&gt;': '>'
    };
    var newtext = text;
    for (var tag in tagsToReplace) {
        if ({}.hasOwnProperty.call(tagsToReplace, tag)) {
            var regex = new RegExp(tag, 'g');
            newtext = newtext.replace(regex, tagsToReplace[tag]);
        }
    }
    return newtext;
}

export function insertHtmlEntities(text) {
    var tagsToReplace = {
        '&': '&amp;',
        '<': '&lt;',
        '>': '&gt;'
    };
    var newtext = text;
    for (var tag in tagsToReplace) {
        if ({}.hasOwnProperty.call(tagsToReplace, tag)) {
            var regex = new RegExp(tag, 'g');
            newtext = newtext.replace(regex, tagsToReplace[tag]);
        }
    }
    return newtext;
}

export function searchForTerm(term) {
    AppDispatcher.handleServerAction({
        type: ActionTypes.RECIEVED_SEARCH_TERM,
        term: term,
        do_search: true
    });
}

export function getFileType(extin) {
    var ext = extin.toLowerCase();
    if (Constants.IMAGE_TYPES.indexOf(ext) > -1) {
        return 'image';
    }

    if (Constants.AUDIO_TYPES.indexOf(ext) > -1) {
        return 'audio';
    }

    if (Constants.VIDEO_TYPES.indexOf(ext) > -1) {
        return 'video';
    }

    if (Constants.SPREADSHEET_TYPES.indexOf(ext) > -1) {
        return 'spreadsheet';
    }

    if (Constants.CODE_TYPES.indexOf(ext) > -1) {
        return 'code';
    }

    if (Constants.WORD_TYPES.indexOf(ext) > -1) {
        return 'word';
    }

    if (Constants.PRESENTATION_TYPES.indexOf(ext) > -1) {
        return 'presentation';
    }

    if (Constants.PDF_TYPES.indexOf(ext) > -1) {
        return 'pdf';
    }

    if (Constants.PATCH_TYPES.indexOf(ext) > -1) {
        return 'patch';
    }

    return 'other';
}

export function getPreviewImagePathForFileType(fileTypeIn) {
    var fileType = fileTypeIn.toLowerCase();

    var icon;
    if (fileType in Constants.ICON_FROM_TYPE) {
        icon = Constants.ICON_FROM_TYPE[fileType];
    } else {
        icon = Constants.ICON_FROM_TYPE.other;
    }

    return '/static/images/icons/' + icon + '.png';
}

export function getIconClassName(fileTypeIn) {
    var fileType = fileTypeIn.toLowerCase();

    if (fileType in Constants.ICON_FROM_TYPE) {
        return Constants.ICON_FROM_TYPE[fileType];
    }

    return 'glyphicon-file';
}

export function splitFileLocation(fileLocation) {
    var fileSplit = fileLocation.split('.');

    var ext = '';
    if (fileSplit.length > 1) {
        ext = fileSplit[fileSplit.length - 1];
        fileSplit.splice(fileSplit.length - 1, 1);
    }

    var filePath = fileSplit.join('.');
    var filename = filePath.split('/')[filePath.split('/').length - 1];

    return {ext: ext, name: filename, path: filePath};
}

export function toTitleCase(str) {
    function doTitleCase(txt) {
        return txt.charAt(0).toUpperCase() + txt.substr(1).toLowerCase();
    }
    return str.replace(/\w\S*/g, doTitleCase);
}

export function applyTheme(theme) {
    if (theme.sidebarBg) {
        changeCss('.sidebar--left', 'background:' + theme.sidebarBg, 1);
        changeCss('@media(max-width: 768px){.search-bar__container', 'background:' + theme.sidebarBg, 1);
    }

    if (theme.sidebarText) {
        changeCss('.sidebar--left .nav li>a, .sidebar--right', 'color:' + theme.sidebarText, 1);
        changeCss('.sidebar--left .nav li>h4, .sidebar--left .add-channel-btn', 'color:' + changeOpacity(theme.sidebarText, 0.8), 1);
        changeCss('.sidebar--left .add-channel-btn:hover, .sidebar--left .add-channel-btn:focus', 'color:' + theme.sidebarText, 1);
        changeCss('.sidebar--left, .sidebar--right .sidebar--right__header', 'border-color:' + changeOpacity(theme.sidebarText, 0.2), 1);
        changeCss('.sidebar--left .status path', 'fill:' + changeOpacity(theme.sidebarText, 0.5), 1);
    }

    if (theme.sidebarUnreadText) {
        changeCss('.sidebar--left .nav li>a.unread-title', 'color:' + theme.sidebarUnreadText + '!important;', 1);
    }

    if (theme.sidebarTextHoverBg) {
        changeCss('.sidebar--left .nav li>a:hover, .sidebar--left .nav li>a:focus', 'background:' + theme.sidebarTextHoverBg, 1);
    }

    if (theme.sidebarTextHoverColor) {
        changeCss('.sidebar--left .nav li>a:hover, .sidebar--left .nav li>a:focus', 'color:' + theme.sidebarTextHoverColor, 2);
    }

    if (theme.sidebarTextActiveBg) {
        changeCss('.sidebar--left .nav li.active a, .sidebar--left .nav li.active a:hover, .sidebar--left .nav li.active a:focus', 'background:' + theme.sidebarTextActiveBg, 1);
    }

    if (theme.sidebarTextActiveColor) {
        changeCss('.sidebar--left .nav li.active a, .sidebar--left .nav li.active a:hover, .sidebar--left .nav li.active a:focus', 'color:' + theme.sidebarTextActiveColor, 2);
    }

    if (theme.sidebarHeaderBg) {
        changeCss('.sidebar--left .team__header, .sidebar--menu .team__header', 'background:' + theme.sidebarHeaderBg, 1);
        changeCss('.modal .modal-header', 'background:' + theme.sidebarHeaderBg, 1);
        changeCss('#navbar .navbar-default', 'background:' + theme.sidebarHeaderBg, 1);
    }

    if (theme.sidebarHeaderTextColor) {
        changeCss('.sidebar--left .team__header .header__info, .sidebar--menu .team__header .header__info', 'color:' + theme.sidebarHeaderTextColor, 1);
        changeCss('.sidebar--left .team__header .user__name, .sidebar--menu .team__header .user__name', 'color:' + changeOpacity(theme.sidebarHeaderTextColor, 0.8), 1);
        changeCss('.sidebar--left .team__header:hover .user__name, .sidebar--menu .team__header:hover .user__name', 'color:' + theme.sidebarHeaderTextColor, 1);
        changeCss('.modal .modal-header .modal-title, .modal .modal-header .modal-title .name, .modal .modal-header button.close', 'color:' + theme.sidebarHeaderTextColor, 1);
        changeCss('#navbar .navbar-default .navbar-brand .heading, ', 'color:' + theme.sidebarHeaderTextColor, 1);
        changeCss('#navbar .navbar-default .navbar-toggle .icon-bar, ', 'background:' + theme.sidebarHeaderTextColor, 1);
    }

    if (theme.onlineIndicator) {
        changeCss('.sidebar--left .status .online--icon', 'fill:' + theme.onlineIndicator, 1);
    }

    if (theme.mentionBj) {
        changeCss('.sidebar--left .nav-pills__unread-indicator', 'background:' + theme.mentionBj, 1);
        changeCss('.sidebar--left .badge', 'background:' + theme.mentionBj, 1);
    }

    if (theme.mentionColor) {
        changeCss('.sidebar--left .nav-pills__unread-indicator', 'color:' + theme.mentionColor, 2);
        changeCss('.sidebar--left .badge', 'color:' + theme.mentionColor, 2);
    }

    if (theme.centerChannelBg) {
        changeCss('.app__content, .markdown__table, .markdown__table tbody tr', 'background:' + theme.centerChannelBg, 1);
        changeCss('#post-list .post-list-holder-by-time', 'background:' + theme.centerChannelBg, 1);
        changeCss('#post-create', 'background:' + theme.centerChannelBg, 1);
        changeCss('.search-bar__container .search__form .search-bar', 'background:' + theme.centerChannelBg, 1);
        changeCss('.date-separator .separator__text, .new-separator .separator__text', 'background:' + theme.centerChannelBg, 1);
        changeCss('.post-image__column .post-image__details', 'background:' + theme.centerChannelBg, 1);
        changeCss('.sidebar--right', 'background:' + theme.centerChannelBg, 1);
    }

    if (theme.centerChannelColor) {
        changeCss('.app__content, .post-create__container .post-create-body .btn-file, .post-create__container .post-create-footer .msg-typing, .loading-screen .loading__content .round', 'color:' + theme.centerChannelColor, 1);
        changeCss('#post-create', 'color:' + theme.centerChannelColor, 2);
        changeCss('.post-body hr', 'background:' + theme.centerChannelColor, 1);
        changeCss('.channel-header .heading', 'color:' + theme.centerChannelColor, 1);
        changeCss('.markdown__table tbody tr:nth-child(2n)', 'background:' + changeOpacity(theme.centerChannelColor, 0.07), 1);
        changeCss('.channel-header__info>div.dropdown .header-dropdown__icon', 'color:' + changeOpacity(theme.centerChannelColor, 0.8), 1);
        changeCss('.channel-header #member_popover', 'color:' + changeOpacity(theme.centerChannelColor, 0.8), 1);
        changeCss('.custom-textarea, .custom-textarea:focus, .preview-container .preview-div, .post-image__column .post-image__details, .sidebar--right .sidebar-right__body, .markdown__table th, .markdown__table td', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
        changeCss('.custom-textarea', 'color:' + theme.centerChannelColor, 1);
        changeCss('.post-image__column', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 2);
        changeCss('.post-image__column .post-image__details', 'color:' + theme.centerChannelColor, 2);
        changeCss('.post-image__column a, .post-image__column a:hover, .post-image__column a:focus', 'color:' + theme.centerChannelColor, 1);
        changeCss('.search-bar__container .search__form .search-bar', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2) + '; color: ' + theme.centerChannelColor, 2);
        changeCss('.search-bar__container .search__form', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
        changeCss('.channel-intro .channel-intro__content', 'background:' + changeOpacity(theme.centerChannelColor, 0.05), 1);
        changeCss('.date-separator .separator__text', 'color:' + theme.centerChannelColor, 2);
        changeCss('.date-separator .separator__hr, .post-right__container .post.post--root hr, .search-item-container', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
        changeCss('.channel-intro', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.2), 1);
        changeCss('.post.current--user .post-body, .post.post--comment.other--root.current--user .post-comment', 'background:' + changeOpacity(theme.centerChannelColor, 0.07), 1);
        changeCss('.post.current--user .post-body, .post.post--comment.other--root.current--user .post-comment, .post.post--comment.other--root .post-comment, .post.same--root .post-body', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.07), 2);
        changeCss('@media(max-width: 1440px){.post.same--root', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.07), 2);
        changeCss('@media(max-width: 1440px){.post.same--root', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.07), 2);
        changeCss('@media(max-width: 1800px){.inner__wrap.move--left .post.post--comment.same--root', 'border-color:' + changeOpacity(theme.centerChannelColor, 0.07), 2);
        changeCss('.post:hover, .sidebar--right .sidebar--right__header', 'background:' + changeOpacity(theme.centerChannelColor, 0.07), 1);
        changeCss('.date-separator.hovered--before:after, .new-separator.hovered--before:after', 'background:' + changeOpacity(theme.centerChannelColor, 0.07), 1);
        changeCss('.date-separator.hovered--after:before, .new-separator.hovered--after:before', 'background:' + changeOpacity(theme.centerChannelColor, 0.07), 1);
        changeCss('.post.current--user:hover .post-body ', 'background: none;', 1);
        changeCss('.sidebar--right', 'color:' + theme.centerChannelColor, 2);
    }

    if (theme.newMessageSeparator) {
        changeCss('.new-separator .separator__text', 'color:' + theme.newMessageSeparator, 1);
        changeCss('.new-separator .separator__hr', 'border-color:' + changeOpacity(theme.newMessageSeparator, 0.5), 1);
    }

    if (theme.linkColor) {
        changeCss('a, a:focus, a:hover', 'color:' + theme.linkColor, 1);
        changeCss('.post .comment-icon__container', 'fill:' + theme.linkColor, 1);
    }

    if (theme.buttonBg) {
        changeCss('.btn.btn-primary', 'background:' + theme.buttonBg, 1);
        changeCss('.btn.btn-primary:hover, .btn.btn-primary:active, .btn.btn-primary:focus', 'background:' + changeColor(theme.buttonBg, -0.25), 1);
    }

    if (theme.buttonColor) {
        changeCss('.btn.btn-primary', 'color:' + theme.buttonColor, 2);
    }
}

export function changeCss(className, classValue, classRepeat) {
    // we need invisible container to store additional css definitions
    var cssMainContainer = $('#css-modifier-container');
    if (cssMainContainer.length === 0) {
        cssMainContainer = $('<div id="css-modifier-container"></div>');
        cssMainContainer.hide();
        cssMainContainer.appendTo($('body'));
    }

    // and we need one div for each class
    var classContainer = cssMainContainer.find('div[data-class="' + className + classRepeat + '"]');
    if (classContainer.length === 0) {
        classContainer = $('<div data-class="' + className + classRepeat + '"></div>');
        classContainer.appendTo(cssMainContainer);
    }

    // append additional style
    classContainer.html('<style>' + className + ' {' + classValue + '}</style>');
}

export function rgb2hex(rgbIn) {
    if (/^#[0-9A-F]{6}$/i.test(rgbIn)) {
        return rgbIn;
    }

    var rgb = rgbIn.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
    function hex(x) {
        return ('0' + parseInt(x, 10).toString(16)).slice(-2);
    }
    return '#' + hex(rgb[1]) + hex(rgb[2]) + hex(rgb[3]);
}

export function placeCaretAtEnd(el) {
    el.focus();
    if (typeof window.getSelection != 'undefined' && typeof document.createRange != 'undefined') {
        var range = document.createRange();
        range.selectNodeContents(el);
        range.collapse(false);
        var sel = window.getSelection();
        sel.removeAllRanges();
        sel.addRange(range);
    } else if (typeof document.body.createTextRange != 'undefined') {
        var textRange = document.body.createTextRange();
        textRange.moveToElementText(el);
        textRange.collapse(false);
        textRange.select();
    }
}

export function getCaretPosition(el) {
    if (el.selectionStart) {
        return el.selectionStart;
    } else if (document.selection) {
        el.focus();

        var r = document.selection.createRange();
        if (r == null) {
            return 0;
        }

        var re = el.createTextRange();
        var rc = re.duplicate();
        re.moveToBookmark(r.getBookmark());
        rc.setEndPoint('EndToStart', re);

        return rc.text.length;
    }
    return 0;
}

export function setSelectionRange(input, selectionStart, selectionEnd) {
    if (input.setSelectionRange) {
        input.focus();
        input.setSelectionRange(selectionStart, selectionEnd);
    } else if (input.createTextRange) {
        var range = input.createTextRange();
        range.collapse(true);
        range.moveEnd('character', selectionEnd);
        range.moveStart('character', selectionStart);
        range.select();
    }
}

export function setCaretPosition(input, pos) {
    setSelectionRange(input, pos, pos);
}

export function getSelectedText(input) {
    var selectedText;
    if (typeof document.selection !== 'undefined') {
        input.focus();
        var sel = document.selection.createRange();
        selectedText = sel.text;
    } else if (typeof input.selectionStart !== 'undefined') {
        var startPos = input.selectionStart;
        var endPos = input.selectionEnd;
        selectedText = input.value.substring(startPos, endPos);
    }

    return selectedText;
}

export function isValidUsername(name) {
    var error = '';
    if (!name) {
        error = 'This field is required';
    } else if (name.length < 3 || name.length > 15) {
        error = 'Must be between 3 and 15 characters';
    } else if (!(/^[a-z0-9\.\-\_]+$/).test(name)) {
        error = "Must contain only letters, numbers, and the symbols '.', '-', and '_'.";
    } else if (!(/[a-z]/).test(name.charAt(0))) {
        error = 'First character must be a letter.';
    } else {
        for (var i = 0; i < Constants.RESERVED_USERNAMES.length; i++) {
            if (name === Constants.RESERVED_USERNAMES[i]) {
                error = 'Cannot use a reserved word as a username.';
                break;
            }
        }
    }

    return error;
}

export function updateTabTitle(name) {
    document.title = name + ' ' + document.title.substring(document.title.lastIndexOf('-'));
}

export function updateAddressBar(channelName) {
    var teamURL = window.location.href.split('/channels')[0];
    history.replaceState('data', '', teamURL + '/channels/' + channelName);
}

export function switchChannel(channel, teammateName) {
    AppDispatcher.handleViewAction({
        type: ActionTypes.CLICK_CHANNEL,
        name: channel.name,
        id: channel.id
    });

    updateAddressBar(channel.name);

    if (channel.type === 'D' && teammateName) {
        updateTabTitle(teammateName);
    } else {
        updateTabTitle(channel.display_name);
    }

    AsyncClient.getChannels(true, true, true);
    AsyncClient.getChannelExtraInfo(true);
    AsyncClient.getPosts(channel.id);

    $('.inner__wrap').removeClass('move--right');
    $('.sidebar--left').removeClass('move--right');

    client.trackPage();

    return false;
}

export function isMobile() {
    return screen.width <= 768;
}

export function isComment(post) {
    if ('root_id' in post) {
        return post.root_id !== '';
    }
    return false;
}

export function getDirectTeammate(channelId) {
    var userIds = ChannelStore.get(channelId).name.split('__');
    var curUserId = UserStore.getCurrentId();
    var teammate = {};

    if (userIds.length !== 2 || userIds.indexOf(curUserId) === -1) {
        return teammate;
    }

    for (var idx in userIds) {
        if (userIds[idx] !== curUserId) {
            teammate = UserStore.getProfile(userIds[idx]);
            break;
        }
    }

    return teammate;
}

Image.prototype.load = function imageLoad(url, progressCallback) {
    var self = this;
    var xmlHTTP = new XMLHttpRequest();
    xmlHTTP.open('GET', url, true);
    xmlHTTP.responseType = 'arraybuffer';
    xmlHTTP.onload = function onLoad() {
        var h = xmlHTTP.getAllResponseHeaders();
        var m = h.match(/^Content-Type\:\s*(.*?)$/mi);
        var mimeType = m[1] || 'image/png';

        var blob = new Blob([this.response], {type: mimeType});
        self.src = window.URL.createObjectURL(blob);
    };
    xmlHTTP.onprogress = function onprogress(e) {
        parseInt(self.completedPercentage = (e.loaded / e.total) * 100, 10);
        if (progressCallback) {
            progressCallback();
        }
    };
    xmlHTTP.onloadstart = function onloadstart() {
        self.completedPercentage = 0;
    };
    xmlHTTP.send();
};

Image.prototype.completedPercentage = 0;

export function changeColor(colourIn, amt) {
    var hex = colourIn;
    var lum = amt;

    // validate hex string
    hex = String(hex).replace(/[^0-9a-f]/gi, '');
    if (hex.length < 6) {
        hex = hex[0] + hex[0] + hex[1] + hex[1] + hex[2] + hex[2];
    }
    lum = lum || 0;

    // convert to decimal and change luminosity
    var rgb = '#';
    var c;
    var i;
    for (i = 0; i < 3; i++) {
        c = parseInt(hex.substr(i * 2, 2), 16);
        c = Math.round(Math.min(Math.max(0, c + (c * lum)), 255)).toString(16);
        rgb += ('00' + c).substr(c.length);
    }

    return rgb;
}

export function changeOpacity(oldColor, opacity) {
    var color = oldColor;
    if (color[0] === '#') {
        color = color.slice(1);
    }

    if (color.length === 3) {
        const tempColor = color;
        color = '';

        color += tempColor[0] + tempColor[0];
        color += tempColor[1] + tempColor[1];
        color += tempColor[2] + tempColor[2];
    }

    var r = parseInt(color.substring(0, 2), 16);
    var g = parseInt(color.substring(2, 4), 16);
    var b = parseInt(color.substring(4, 6), 16);

    return 'rgba(' + r + ',' + g + ',' + b + ',' + opacity + ')';
}

export function getFullName(user) {
    if (user.first_name && user.last_name) {
        return user.first_name + ' ' + user.last_name;
    } else if (user.first_name) {
        return user.first_name;
    } else if (user.last_name) {
        return user.last_name;
    }

    return '';
}

export function getDisplayName(user) {
    if (user.nickname && user.nickname.trim().length > 0) {
        return user.nickname;
    }
    var fullName = getFullName(user);

    if (fullName) {
        return fullName;
    }

    return user.username;
}

//IE10 does not set window.location.origin automatically so this must be called instead when using it
export function getWindowLocationOrigin() {
    var windowLocationOrigin = window.location.origin;
    if (!windowLocationOrigin) {
        windowLocationOrigin = window.location.protocol + '//' + window.location.hostname;
        if (window.location.port) {
            windowLocationOrigin += ':' + window.location.port;
        }
    }
    return windowLocationOrigin;
}

// Converts a file size in bytes into a human-readable string of the form '123MB'.
export function fileSizeToString(bytes) {
    // it's unlikely that we'll have files bigger than this
    if (bytes > 1024 * 1024 * 1024 * 1024) {
        return Math.floor(bytes / (1024 * 1024 * 1024 * 1024)) + 'TB';
    } else if (bytes > 1024 * 1024 * 1024) {
        return Math.floor(bytes / (1024 * 1024 * 1024)) + 'GB';
    } else if (bytes > 1024 * 1024) {
        return Math.floor(bytes / (1024 * 1024)) + 'MB';
    } else if (bytes > 1024) {
        return Math.floor(bytes / 1024) + 'KB';
    }

    return bytes + 'B';
}

// Converts a filename (like those attached to Post objects) to a url that can be used to retrieve attachments from the server.
export function getFileUrl(filename) {
    var url = filename;

    // This is a temporary patch to fix issue with old files using absolute paths
    if (url.indexOf('/api/v1/files/get') !== -1) {
        url = filename.split('/api/v1/files/get')[1];
    }
    url = getWindowLocationOrigin() + '/api/v1/files/get' + url;

    return url;
}

// Gets the name of a file (including extension) from a given url or file path.
export function getFileName(path) {
    var split = path.split('/');
    return split[split.length - 1];
}

// Generates a RFC-4122 version 4 compliant globally unique identifier.
export function generateId() {
    // implementation taken from http://stackoverflow.com/a/2117523
    var id = 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx';

    id = id.replace(/[xy]/g, function replaceRandom(c) {
        var r = Math.floor(Math.random() * 16);

        var v;
        if (c === 'x') {
            v = r;
        } else {
            v = r & 0x3 | 0x8;
        }

        return v.toString(16);
    });

    return id;
}

export function isBrowserFirefox() {
    return navigator && navigator.userAgent && navigator.userAgent.toLowerCase().indexOf('firefox') > -1;
}

// Checks if browser is IE10 or IE11
export function isBrowserIE() {
    if (window.navigator && window.navigator.userAgent) {
        var ua = window.navigator.userAgent;

        return ua.indexOf('Trident/7.0') > 0 || ua.indexOf('Trident/6.0') > 0;
    }

    return false;
}

export function isBrowserEdge() {
    return window.naviagtor && navigator.userAgent && navigator.userAgent.toLowerCase().indexOf('edge') > -1;
}

// Used to get the id of the other user from a DM channel
export function getUserIdFromChannelName(channel) {
    var ids = channel.name.split('__');
    var otherUserId = '';
    if (ids[0] === UserStore.getCurrentId()) {
        otherUserId = ids[1];
    } else {
        otherUserId = ids[0];
    }

    return otherUserId;
}

export function importSlack(file, success, error) {
    var formData = new FormData();
    formData.append('file', file, file.name);
    formData.append('filesize', file.size);
    formData.append('importFrom', 'slack');

    client.importSlack(formData, success, error);
}

export function getTeamURLFromAddressBar() {
    return window.location.href.split('/channels')[0];
}

export function getShortenedTeamURL() {
    const teamURL = getTeamURLFromAddressBar();
    if (teamURL.length > 35) {
        return teamURL.substring(0, 10) + '...' + teamURL.substring(teamURL.length - 12, teamURL.length) + '/';
    }
    return teamURL + '/';
}