/**
 * AGC Analytics - Lightweight Tracking Script
 * Version: 1.0.0
 * 
 * Include this script in your AGC sites:
 * <script src="proxy.php?url=https%3A%2F%2Fyour-dashboard.com%2Ftracking.js" data-domain="yourdomain.com" async></script>
 */

(function () {
    'use strict';

    // Configuration
    const SCRIPT = document.currentScript;
    const DOMAIN = SCRIPT?.getAttribute('data-domain') || window.location.hostname;
    const ENDPOINT = SCRIPT?.src.replace('/tracking.js', '/api/track') || '/api/track';
    const SESSION_TIMEOUT = 30 * 60 * 1000; // 30 minutes

    // Check for opt-out
    if (localStorage.getItem('agc_optout') === '1') {
        return;
    }

    // Get or create session ID
    function getSessionId() {
        const stored = sessionStorage.getItem('agc_session');
        if (stored) {
            const data = JSON.parse(stored);
            if (Date.now() - data.lastActivity < SESSION_TIMEOUT) {
                data.lastActivity = Date.now();
                sessionStorage.setItem('agc_session', JSON.stringify(data));
                return data.id;
            }
        }

        const newSession = {
            id: Math.random().toString(36).substring(2) + Date.now().toString(36),
            lastActivity: Date.now(),
            pageViews: 0,
        };
        sessionStorage.setItem('agc_session', JSON.stringify(newSession));
        return newSession.id;
    }

    // Parse user agent
    function parseUserAgent() {
        const ua = navigator.userAgent;

        // Browser detection
        let browser = 'Unknown';
        if (ua.includes('Firefox/')) browser = 'Firefox';
        else if (ua.includes('Edg/')) browser = 'Edge';
        else if (ua.includes('Chrome/')) browser = 'Chrome';
        else if (ua.includes('Safari/') && !ua.includes('Chrome')) browser = 'Safari';
        else if (ua.includes('Opera') || ua.includes('OPR/')) browser = 'Opera';

        // OS detection
        let os = 'Unknown';
        if (ua.includes('Windows')) os = 'Windows';
        else if (ua.includes('Mac OS')) os = 'macOS';
        else if (ua.includes('Linux')) os = 'Linux';
        else if (ua.includes('Android')) os = 'Android';
        else if (ua.includes('iOS') || ua.includes('iPhone') || ua.includes('iPad')) os = 'iOS';

        // Device detection
        let device = 'Desktop';
        if (/Mobile|Android|iPhone/i.test(ua)) device = 'Mobile';
        else if (/iPad|Tablet/i.test(ua)) device = 'Tablet';

        return { browser, os, device };
    }

    // Get referrer type
    function getReferrer() {
        const ref = document.referrer;
        if (!ref) return { url: '', type: 'direct' };

        try {
            const refUrl = new URL(ref);
            if (refUrl.hostname === window.location.hostname) {
                return { url: ref, type: 'internal' };
            }

            // Check for search engines
            const searchEngines = ['google', 'bing', 'yahoo', 'duckduckgo', 'baidu', 'yandex'];
            for (const se of searchEngines) {
                if (refUrl.hostname.includes(se)) {
                    return { url: ref, type: 'search', engine: se };
                }
            }

            // Check for social
            const social = ['facebook', 'twitter', 'instagram', 'linkedin', 'pinterest', 'reddit', 'tiktok'];
            for (const s of social) {
                if (refUrl.hostname.includes(s)) {
                    return { url: ref, type: 'social', platform: s };
                }
            }

            return { url: ref, type: 'referral' };
        } catch (e) {
            return { url: ref, type: 'referral' };
        }
    }

    // Get country from Cloudflare trace (most accurate)
    async function getCountryFromCloudflare() {
        try {
            const response = await fetch('https://1.1.1.1/cdn-cgi/trace');
            const text = await response.text();
            // Parse text format: look for "loc=ID" pattern
            const match = text.match(/loc=([A-Z]{2})/);
            return match ? match[1] : 'Unknown';
        } catch (e) {
            // Fallback to timezone-based detection
            return getCountryFromTimezone();
        }
    }

    // Fallback: Get country from browser timezone
    function getCountryFromTimezone() {
        try {
            const tz = Intl.DateTimeFormat().resolvedOptions().timeZone;
            const tzToCountry = {
                'Asia/Jakarta': 'ID', 'Asia/Makassar': 'ID', 'Asia/Jayapura': 'ID',
                'Asia/Singapore': 'SG', 'Asia/Kuala_Lumpur': 'MY', 'Asia/Bangkok': 'TH',
                'Asia/Ho_Chi_Minh': 'VN', 'Asia/Manila': 'PH', 'Asia/Tokyo': 'JP',
                'Asia/Seoul': 'KR', 'Asia/Shanghai': 'CN', 'Asia/Hong_Kong': 'HK',
                'Asia/Kolkata': 'IN', 'Asia/Dubai': 'AE',
                'America/New_York': 'US', 'America/Chicago': 'US', 'America/Los_Angeles': 'US',
                'America/Toronto': 'CA', 'America/Sao_Paulo': 'BR',
                'Europe/London': 'GB', 'Europe/Paris': 'FR', 'Europe/Berlin': 'DE',
                'Europe/Moscow': 'RU', 'Australia/Sydney': 'AU',
            };
            return tzToCountry[tz] || 'Unknown';
        } catch (e) {
            return 'Unknown';
        }
    }

    // Track page view
    async function trackPageView() {
        const session = getSessionId();
        const { browser, os, device } = parseUserAgent();
        const referrer = getReferrer();
        const country = await getCountryFromCloudflare();

        // Update session page views
        const sessionData = JSON.parse(sessionStorage.getItem('agc_session'));
        sessionData.pageViews++;
        sessionStorage.setItem('agc_session', JSON.stringify(sessionData));

        const data = {
            domain: DOMAIN,
            path: window.location.pathname,
            title: document.title,
            referrer: referrer.url,
            referrerType: referrer.type,
            browser: browser,
            os: os,
            device: device,
            screenWidth: window.screen.width,
            screenHeight: window.screen.height,
            language: navigator.language,
            sessionId: session,
            isNewSession: sessionData.pageViews === 1,
            timestamp: Date.now(),
            country: country,
        };

        // Send using sendBeacon for reliability
        if (navigator.sendBeacon) {
            navigator.sendBeacon(ENDPOINT, JSON.stringify(data));
        } else {
            // Fallback to fetch
            fetch(ENDPOINT, {
                method: 'POST',
                body: JSON.stringify(data),
                headers: { 'Content-Type': 'application/json' },
                keepalive: true,
            }).catch(() => { });
        }
    }

    // Track on page load
    if (document.readyState === 'complete') {
        trackPageView();
    } else {
        window.addEventListener('load', trackPageView);
    }

    // Track SPA navigation (if applicable)
    let lastPath = window.location.pathname;
    const observer = new MutationObserver(() => {
        if (window.location.pathname !== lastPath) {
            lastPath = window.location.pathname;
            trackPageView();
        }
    });

    observer.observe(document.body, { childList: true, subtree: true });

    // Track time on page (for session duration)
    let startTime = Date.now();
    window.addEventListener('beforeunload', () => {
        const timeOnPage = Math.round((Date.now() - startTime) / 1000);
        const data = {
            domain: DOMAIN,
            type: 'duration',
            sessionId: getSessionId(),
            duration: timeOnPage,
            path: window.location.pathname,
        };

        if (navigator.sendBeacon) {
            navigator.sendBeacon(ENDPOINT, JSON.stringify(data));
        }
    });

})();