tracking.js

```javascript
// Initialize map
const map = L.map('map').setView([37.5665, 126.9780], 13); // Default to Seoul
L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
}).addTo(map);

// Tracking variables
let tracking = false;
let startTime = null;
let path = [];
let polyline = null;
let totalDistance = 0;
let watchId = null;

// DOM elements
const startBtn = document.getElementById('startBtn');
const stopBtn = document.getElementById('stopBtn');
const saveBtn = document.getElementById('saveBtn');
const distanceEl = document.getElementById('distance');
const durationEl = document.getElementById('duration');
const speedEl = document.getElementById('speed');
const caloriesEl = document.getElementById('calories');
const historyTable = document.getElementById('historyTable');

// Event listeners
startBtn.addEventListener('click', startTracking);
stopBtn.addEventListener('click', stopTracking);
saveBtn.addEventListener('click', saveSession);

function startTracking() {
    tracking = true;
    startTime = new Date();
    path = [];
    totalDistance = 0;
    
    if (polyline) {
        map.removeLayer(polyline);
    }
    
    startBtn.disabled = true;
    stopBtn.disabled = false;
    saveBtn.disabled = true;
    
    watchId = navigator.geolocation.watchPosition(
        updatePosition,
        handleError,
        { enableHighAccuracy: true, maximumAge: 10000, timeout: 5000 }
    );
    
    updateTimer();
    timerInterval = setInterval(updateTimer, 1000);
}

function stopTracking() {
    tracking = false;
    if (watchId) {
        navigator.geolocation.clearWatch(watchId);
    }
    
    startBtn.disabled = false;
    stopBtn.disabled = true;
    saveBtn.disabled = false;
    
    clearInterval(timerInterval);
}

function saveSession() {
    // Save to local storage
    const sessions = JSON.parse(localStorage.getItem('trackingSessions') || '[]');
    const duration = (new Date() - startTime) / 1000;
    
    sessions.push({
        date: new Date().toLocaleString(),
        distance: totalDistance,
        duration: formatTime(duration),
        path: path
    });
    
    localStorage.setItem('trackingSessions', JSON.stringify(sessions));
    updateHistoryTable();
    saveBtn.disabled = true;
}

function updatePosition(position) {
    const { latitude, longitude, speed, altitude } = position.coords;
    const newPoint = [latitude, longitude];
    
    // Add to path
    path.push(newPoint);
    
    // Update polyline
    if (polyline) {
        map.removeLayer(polyline);
    }
    polyline = L.polyline(path, {color: 'blue'}).addTo(map);
    
    // Calculate distance
    if (path.length > 1) {
        const lastPoint = path[path.length - 2];
        const distance = calculateDistance(lastPoint[0], lastPoint[1], latitude, longitude);
        totalDistance += distance;
        distanceEl.textContent = (totalDistance / 1000).toFixed(2);
    }
    
    // Update speed
    const speedKmh = speed ? (speed * 3.6).toFixed(1) : 0;
    speedEl.textContent = speedKmh;
    
    // Estimate calories (very rough estimate)
    const calories = (totalDistance / 1000) * 60; // 60kcal per km
    caloriesEl.textContent = Math.round(calories);
    
    // Center map on current position
    map.setView(newPoint, map.getZoom());
}

function handleError(error) {
    console.error('Geolocation error:', error.message);
    if (tracking) {
        stopTracking();
        alert('Geolocation error: ' + error.message);
    }
}

function updateTimer() {
    if (!startTime) return;
    const elapsed = (new Date() - startTime) / 1000;
    durationEl.textContent = formatTime(elapsed);
}

function formatTime(seconds) {
    const hrs = Math.floor(seconds / 3600);
    const mins = Math.floor((seconds % 3600) / 60);
    const secs = Math.floor(seconds % 60);
    return `${hrs.toString().padStart(2, '0')}:${mins.toString().padStart(2, '0')}:${secs.toString().padStart(2, '0')}`;
}

function calculateDistance(lat1, lon1, lat2, lon2) {
    const R = 6371e3; // Earth radius in meters
    const φ1 = lat1 * Math.PI/180;
    const φ2 = lat2 * Math.PI/180;
    const Δφ = (lat2-lat1) * Math.PI/180;
    const Δλ = (lon2-lon1) * Math.PI/180;

    const a = Math.sin(Δφ/2) * Math.sin(Δφ/2) +
              Math.cos(φ1) * Math.cos(φ2) *
              Math.sin(Δλ/2) * Math.sin(Δλ/2);
    const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));

    return R * c;
}

function updateHistoryTable() {
    const sessions = JSON.parse(localStorage.getItem('trackingSessions') || '[]');
    
    historyTable.innerHTML = sessions.map(session => `
        <tr>
            <td>${session.date}</td>
            <td>${(session.distance / 1000).toFixed(2)} km</td>
            <td>${session.duration}</td>
            <td><button class="btn btn-sm btn-outline-primary">View</button></td>
        </tr>
    `).join('');
}

// Initialize
updateHistoryTable();
```