function formatBytes(bytes) {
    if (bytes === 0) return '0 B';
    const k = 1024;
    const sizes = ['B', 'KB', 'MB', 'GB'];
    const i = Math.floor(Math.log(bytes) / Math.log(k));
    return `${parseFloat((bytes / k ** i).toFixed(2))} ${sizes[i]}`;
}

function formatUptime(seconds) {
    const days = Math.floor(seconds / 86400);
    const hours = Math.floor((seconds % 86400) / 3600);
    const mins = Math.floor((seconds % 3600) / 60);
    if (days > 0) return `${days}d ${hours}h`;
    if (hours > 0) return `${hours}h ${mins}m`;
    return `${mins}m`;
}

const regionNames = (typeof Intl !== 'undefined' && Intl.DisplayNames)
    ? new Intl.DisplayNames([navigator.language || 'en'], { type: 'region' })
    : null;

function getCountryName(countryCode) {
    if (!countryCode || countryCode === 'Unknown') return 'Unknown';
    const normalized = String(countryCode).trim().toUpperCase();
    if (!normalized || normalized.length !== 2) return 'Unknown';

    try {
        const name = regionNames?.of(normalized);
        return name || normalized;
    } catch {
        return normalized;
    }
}

function getFlag(countryCode) {
    if (!countryCode || countryCode === 'Unknown') return '🌐';
    const normalized = String(countryCode).trim().toUpperCase();
    if (normalized.length !== 2) return '🌐';
    const codePoints = normalized
        .split('')
        .map(char => 127397 + char.charCodeAt(0));
    return String.fromCodePoint(...codePoints);
}

function formatKB(kbString) {
    const kb = parseFloat(kbString);
    if (kb >= 1024 * 1024) return `${(kb / 1024 / 1024).toFixed(2)} GB`;
    if (kb >= 1024) return `${(kb / 1024).toFixed(2)} MB`;
    return `${kb.toFixed(2)} KB`;
}

async function fetchLogs() {
    try {
        const response = await fetch('/internal/logs');
        const text = await response.text();
        
        const logDiv = document.getElementById('activity-log');
        const lines = text.split('\n')
            .filter(line => line.includes('In the last'))
            .reverse();
        
        if (lines.length === 0) {
            logDiv.innerHTML = '<div class="loading">No activity logs available</div>';
            return;
        }
        
        const rows = lines.map(line => {
            const match = line.match(/(\d{4}\/\d{2}\/\d{2} \d{2}:\d{2}:\d{2}).*?(\d+) completed.*?↓ ([\d.]+) KB \(([\d.]+) KB\/s\).*?↑ ([\d.]+) KB \(([\d.]+) KB\/s\)/);
            if (!match) return '';
            
            const [, timestamp, connections, dlTotal, dlRate, ulTotal, ulRate] = match;
            const utcDate = new Date(`${timestamp.replace(/\//g, '-')}Z`);
            const time = utcDate.toLocaleTimeString([], { hour: '2-digit', minute: '2-digit' });
            const fullDate = utcDate.toLocaleDateString([], { year: 'numeric', month: 'short', day: 'numeric', hour: '2-digit', minute: '2-digit', second: '2-digit' });
            
            return `<tr>
                <td title="${fullDate}">${time}</td>
                <td>${connections}</td>
                <td>${formatKB(dlTotal)} <span class="rate">(${formatKB(dlRate)}/s)</span></td>
                <td>${formatKB(ulTotal)} <span class="rate">(${formatKB(ulRate)}/s)</span></td>
            </tr>`;
        }).join('');
        
        logDiv.innerHTML = `<table class="activity-table">
            <tr>
                <th>Time</th>
                <th>Conns</th>
                <th>Download</th>
                <th>Upload</th>
            </tr>
            ${rows}
        </table>`;
    } catch (_e) {
        document.getElementById('activity-log').innerHTML = '<div class="error">Error loading logs</div>';
    }
}

async function fetchNatType() {
    try {
        const response = await fetch('/internal/nat');
        const text = await response.text();
        const natType = text.trim() || 'Unknown';
        const el = document.getElementById('nat-type');
        const row = document.getElementById('nat-row');

        const isUnknown = !natType || natType.toLowerCase() === 'unknown';
        if (row) row.hidden = isUnknown;
        if (el && !isUnknown) {
            const capitalized = natType.charAt(0).toUpperCase() + natType.slice(1).toLowerCase();
            el.textContent = capitalized;
        }
    } catch (_e) {
        const el = document.getElementById('nat-type');
        const row = document.getElementById('nat-row');
        if (row) row.hidden = false;
        if (el) el.innerHTML = '<span class="error">Error</span>';
    }
}

async function fetchStats() {
    try {
        const response = await fetch('/internal/metrics');
        const text = await response.text();
        
        let total = 0;
        let timeouts = 0;
        let inbound = 0;
        let outbound = 0;
        let torInbound = 0;
        let torOutbound = 0;
        let memory = 0;
        let startTime = 0;
        const countries = {};
        
        text.split('\n').forEach(line => {
            if (line.startsWith('tor_snowflake_proxy_connections_total')) {
                const match = line.match(/country="([^"]*)".*?(\d+)$/);
                if (match) {
                    const country = match[1] || 'Unknown';
                    const count = parseInt(match[2], 10);
                    countries[country] = count;
                    total += count;
                }
            } else if (line.startsWith('tor_snowflake_proxy_connection_timeouts_total')) {
                const match = line.match(/(\d+)$/);
                if (match) timeouts = parseInt(match[1], 10);
            } else if (line.startsWith('process_network_receive_bytes_total')) {
                const match = line.match(/(\d+\.?\d*e?\+?\d*)$/);
                if (match) inbound = parseFloat(match[1]);
            } else if (line.startsWith('process_network_transmit_bytes_total')) {
                const match = line.match(/(\d+\.?\d*e?\+?\d*)$/);
                if (match) outbound = parseFloat(match[1]);
            } else if (line.startsWith('tor_snowflake_proxy_traffic_inbound_bytes_total')) {
                const match = line.match(/(\d+\.?\d*e?\+?\d*)$/);
                if (match) torInbound = parseFloat(match[1]) * 1024;
            } else if (line.startsWith('tor_snowflake_proxy_traffic_outbound_bytes_total')) {
                const match = line.match(/(\d+\.?\d*e?\+?\d*)$/);
                if (match) torOutbound = parseFloat(match[1]) * 1024;
            } else if (line.startsWith('process_resident_memory_bytes')) {
                const match = line.match(/(\d+\.?\d*e?\+?\d*)$/);
                if (match) memory = parseFloat(match[1]);
            } else if (line.startsWith('process_start_time_seconds')) {
                const match = line.match(/(\d+\.?\d*e?\+?\d*)$/);
                if (match) startTime = parseFloat(match[1]);
            }
        });
        
        const attempts = total + timeouts;
        const successRate = attempts > 0 ? ((total / attempts) * 100).toFixed(1) : 0;
        const uptime = startTime > 0 ? Date.now() / 1000 - startTime : 0;
        
        document.getElementById('total').textContent = total;
        document.getElementById('timeouts').textContent = timeouts;
        document.getElementById('success-rate').textContent = `${successRate}%`;
        document.getElementById('total-traffic').textContent = `${formatBytes(inbound)} / ${formatBytes(outbound)}`;
        document.getElementById('tor-traffic').textContent = `${formatBytes(torInbound)} / ${formatBytes(torOutbound)}`;
        document.getElementById('memory').textContent = formatBytes(memory);
        document.getElementById('uptime').textContent = formatUptime(uptime);
        
        const table = document.getElementById('countries');
        table.innerHTML = '<tr><th>Country</th><th>Count</th></tr>';
        Object.entries(countries).sort((a, b) => b[1] - a[1]).forEach(([country, count]) => {
            const row = table.insertRow();
            const displayName = getCountryName(country);

            const countryCell = row.insertCell(0);
            const flagSpan = document.createElement('span');
            flagSpan.className = 'flag';
            flagSpan.textContent = getFlag(country);
            countryCell.appendChild(flagSpan);
            countryCell.appendChild(document.createTextNode(displayName));

            row.insertCell(1).textContent = count;
        });
    } catch (_e) {
        document.getElementById('total').innerHTML = '<span class="error">Error</span>';
    }
}

fetchStats();
fetchLogs();
fetchNatType();
setInterval(fetchStats, 300000);
setInterval(fetchLogs, 300000);