var sc = document.currentScript;

(function() {
    var visitTime = null;
    var visitStart = new Date().getTime();
    var url = sc.dataset.endpoint || 'https://img.alceris.com/';
    var debug = !!sc.dataset.debug;

    function _send(type, name, eventData) {
        if (/(bot|spider|crawl)/i.test(navigator.userAgent) || window.navigator.webdriver) return;

        // Overwrite type to link when link tracking is active
        if (sc.dataset.linkTracking) type = 'link';

        var data = {};
        if (type == 'pageview') {
            if (visitTime !== null) {
                data.t = Math.round((new Date().getTime() - visitStart) / 1000);
                visitStart = new Date().getTime();
            }

            visitTime = 0;
            data._ = 'pv';
        } else if (type == 'outgoing_link') {
            data._ = 'ol';
            data.ol = name;
        } else if (type == 'event') {
            data._ = 'ev';
            data.en = name;

            if (eventData) {
                data.ed = eventData;
            }
        } else if (type == 'error') {
            data._ = 'err';

            data.msg = name
            if (eventData) {
                data.err = eventData;
            }
        } else if (type == 'link') {
            data._ = 'l';
            data.link = sc.dataset.linkTracking;
        }

        data.r = document.referrer;
        data.l = navigator.language;
        data.loc = window.location.origin + window.location.pathname + window.location.search;
        data._id = sc.dataset.id;
        
        if (!data._id) return;

        try {
            data.tz = Intl.DateTimeFormat().resolvedOptions().timeZone;
        } catch (err) {
            data.tz = null;
        }
        
        fetch(url, {
            method: 'POST',
            mode: 'no-cors',
            headers: {
                'Content-Type': 'application/json'
            },
            keepalive: true,
            body: JSON.stringify(data)
        });
    };

    function ol(ev) {
        if (!ev) return;

        var target = ev.path && ev.path.find(function(n) { return n.tagName === 'A' });
        if (!target) {
            var elem = ev.target;
            while (elem != null) {
                if (elem.tagName === 'A') {
                    target = elem;
                    break;
                }

                elem = elem.parentElement;
            }
        }

        if(target && target.href.length > 0) {
            if (target.href.indexOf(window.location.origin) === -1) {
                _send('outgoing_link', target.href);
            } else {
                // User navigates to another page
                _send('pageview');
            }
        }
    }

    if (document.readyState === 'complete') {
        _send('pageview');
    } else {
        document.addEventListener('readystatechange', function() {
            if (document.readyState === 'complete') {
                setTimeout(function() {
                    _send('pageview');
                });
            }
        });
    }

    window.document.addEventListener('click', ol);
    window.document.addEventListener('auxclick', ol);
        
    window.addEventListener('visibilitychange', function() {
        if (document.visibilityState == 'visible') {
            visitStart = new Date().getTime();
        } else if (document.visibilityState == 'hidden') {
            _send('pageview');
        }
    });

    window.addEventListener('pagehide', function() {
        _send('pageview');
    });

    window.addEventListener('popstate', function() {
        _send('pageview')
    });

    var pS = window.history.pushState;
    window.history.pushState = function() {
        pS.apply(this, arguments);
        _send('pageview');
    };

    window.alceris = _send;

    if (window._alcerisData && Array.isArray(window._alcerisData)) {
        while (window._alcerisData.length > 0) {
            _send(...window._alcerisData.shift());
        }
    }

    if (sc.dataset.gaCompat) {
        var origGa = window.ga;
        window.ga = function(action, type, eventCategory, eventAction, eventLabel, eventValue, fields) {
            if (origGa) origGa(...arguments);
            
            if (action != 'send') return;

            if (type == 'pageview') _send('pageview');
            if (type == 'event') _send('event', eventCategory, { action: eventAction, label: eventLabel, value: eventValue, ...fields })
            
            // ga('send', 'event', [eventCategory], [eventAction], [eventLabel], [eventValue], [fieldsObject]);
        };

        var origGtag = window.gtag;
        window.gtag = function(type, data) {
            if (origGtag) origGtag(...arguments);

            if (type == 'event') _send('event', data);
        }
    }

    if (sc.dataset.errorReporting) {
        window.addEventListener('error', function(err) {
            try {
                _send('error', err.message, { stack: err.error ? err.error.stack : undefined, fileName: err.filename, lineNo: err.lineno, colNo: err.colno });
            } catch (err) {
                debug && console.error('[Alceris Analytics] Failed to report error', err);
            }
        });
    }
}());