(document => {
    'use strict';
    const mangleurls = () => {
        for (let el of document.getElementsByTagName('a')) {
            const href = el.href.replace(/^javascript:location=(.*);void 0$/, '$1');
            el.setAttribute('data-href', el.href);
            if (href != el.href) el.href = eval(href);
            else el.href = 'https://alxu.ca/analytics?url=' + href.replace(/[%&;]/g, s=>'%'+s.charCodeAt(0).toString(16));
        }
    };
    if (location.hostname === 'www.alxu.ca') {
        let timeout, pending = [];
        const flush = () => {
            clearTimeout(timeout);
            navigator.sendBeacon('/analytics', new Blob([JSON.stringify(pending)], {type: 'application/json'}));
            pending = [];
        };
        const queue = (kind, details) => {
            clearTimeout(timeout);
            pending.push({created_ts: Date.now(), kind: kind, details: details});
            timeout = setTimeout(flush, 2000);
        };
        queue('l', '');
        document.addEventListener('visibilitychange', () => {
            queue('v', document.visibilityState);
            if (document.visibilityState === 'hidden')
                flush();
        });
        document.addEventListener('click', e => {
            const a = e.target.closest('a');
            if (a)
                queue('c', a.href);
        });
        window.addEventListener('beforeprint', mangleurls);
        window.addEventListener('afterprint', () => {
            for (let el of document.getElementsByTagName('a')) {
                el.href = el.getAttribute('data-href');
                el.removeAttribute('data-href');
            }
        });
    } else {
        mangleurls();
    }
    const css = document.styleSheets[0];
    if (window.safari) {
        css.insertRule('@media print{@page{margin:10mm}}', css.cssRules.length);
        css.insertRule('@media print{body{margin:-2mm 0 -2mm 0;padding:0 15mm 0 7mm}}', css.cssRules.length);
    }
    else if (window.chrome)
        // changing @page causes chrome to claim layout shift even in non-print
        css.insertRule('@media print{@page{margin-top:auto;margin-bottom:auto}}', css.cssRules.length);
})(document);