app/pages/index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script src="../../../node_modules/jquery/dist/jquery.js"></script>
</head>
<body>
</body>
<script>
    function getLanguageFolder(code) {
        if (code === 'ru') {
            return 'Russian';
        }
        if (code === 'es') {
            return 'Spain';
        }
        if (code === 'cn') {
            return 'Chinese';
        }
        return 'English';
    }
    function getRedirectUrl(languageFolder) {
        var currentUrl = new URL(window.location.href);
        var pathname = currentUrl.pathname || '/';
        var pagesMarker = '/app/pages/';
        var targetPath = '';
        if (pathname.indexOf(pagesMarker) > -1) {
            targetPath = pathname.replace(
                /\/app\/pages(?:\/index\.html|\/)?$/i,
                '/app/pages/' + languageFolder + '/index.html'
            );
            if (targetPath === pathname) {
                targetPath = pathname.split(pagesMarker)[0] + pagesMarker + languageFolder + '/index.html';
            }
        } else {
            var basePath = pathname.replace(/\/?index\.html$/i, '').replace(/\/$/, '');
            if (!basePath || basePath === '/') {
                basePath = '/pc';
            }
            targetPath = basePath + '/app/pages/' + languageFolder + '/index.html';
        }
        currentUrl.pathname = targetPath.replace(/\/{2,}/g, '/');
        return currentUrl.toString();
    }
    function redirectToLanguage(code) {
        var targetUrl = getRedirectUrl(getLanguageFolder(code));
        if (targetUrl !== window.location.href) {
            window.location.replace(targetUrl);
        }
    }
    $.get('http://www.ccdcdf.com:6080/api/index/index', function(res) {
        redirectToLanguage(res && res.data ? res.data.code : '');
    }).fail(function() {
        redirectToLanguage('');
    });
</script>
</html>