/**
 * Dashboard animations and interactivity
 */

// Initialize animations when DOM is loaded
document.addEventListener('DOMContentLoaded', () => {
    initializeAnimations();
    initializeCharts();
    initializeEventListeners();
});

// Animation utilities
const animate = {
    fadeIn: (element, delay = 0) => {
        element.style.opacity = '0';
        element.style.transform = 'translateY(20px)';
        
        setTimeout(() => {
            element.style.transition = 'all 0.5s ease';
            element.style.opacity = '1';
            element.style.transform = 'translateY(0)';
        }, delay);
    },
    
    slideIn: (element, direction = 'left', delay = 0) => {
        const transforms = {
            left: 'translateX(-50px)',
            right: 'translateX(50px)',
            up: 'translateY(50px)',
            down: 'translateY(-50px)'
        };
        
        element.style.opacity = '0';
        element.style.transform = transforms[direction];
        
        setTimeout(() => {
            element.style.transition = 'all 0.5s ease';
            element.style.opacity = '1';
            element.style.transform = 'translate(0)';
        }, delay);
    },
    
    pulse: (element) => {
        element.style.transform = 'scale(1)';
        element.style.transition = 'transform 0.2s ease';
        
        element.style.transform = 'scale(1.05)';
        setTimeout(() => {
            element.style.transform = 'scale(1)';
        }, 200);
    }
};

// Initialize animations
function initializeAnimations() {
    // Animate stat cards
    const statCards = document.querySelectorAll('.stat-card');
    statCards.forEach((card, index) => {
        animate.fadeIn(card, index * 100);
    });
    
    // Animate charts
    const charts = document.querySelectorAll('.chart-container');
    charts.forEach((chart, index) => {
        animate.slideIn(chart, 'up', 300 + index * 100);
    });
    
    // Animate session cards
    const sessionCards = document.querySelectorAll('.session-card');
    sessionCards.forEach((card, index) => {
        animate.slideIn(card, 'right', 500 + index * 100);
    });
}

// Initialize Charts
function initializeCharts() {
    // Traffic Chart
    const trafficChart = document.getElementById('traffic-chart');
    if (trafficChart) {
        new Chart(trafficChart, {
            type: 'line',
            data: {
                labels: getLastNHours(24),
                datasets: [{
                    label: 'Upload',
                    data: generateRandomData(24),
                    borderColor: '#4F46E5',
                    tension: 0.4
                }, {
                    label: 'Download',
                    data: generateRandomData(24),
                    borderColor: '#10B981',
                    tension: 0.4
                }]
            },
            options: {
                responsive: true,
                maintainAspectRatio: false,
                plugins: {
                    legend: {
                        position: 'top'
                    }
                },
                scales: {
                    y: {
                        beginAtZero: true
                    }
                }
            }
        });
    }
    
    // Protocol Distribution Chart
    const protocolChart = document.getElementById('protocol-chart');
    if (protocolChart) {
        new Chart(protocolChart, {
            type: 'doughnut',
            data: {
                labels: ['Shadowsocks', 'IKEv2', 'L2TP', 'PPTP'],
                datasets: [{
                    data: [40, 30, 20, 10],
                    backgroundColor: [
                        '#4F46E5',
                        '#10B981',
                        '#F59E0B',
                        '#EF4444'
                    ]
                }]
            },
            options: {
                responsive: true,
                maintainAspectRatio: false,
                plugins: {
                    legend: {
                        position: 'bottom'
                    }
                }
            }
        });
    }
}

// Initialize Event Listeners
function initializeEventListeners() {
    // Quick Action Buttons
    const quickActions = document.querySelectorAll('.quick-action');
    quickActions.forEach(action => {
        action.addEventListener('mouseenter', () => {
            animate.pulse(action);
        });
    });
    
    // Responsive Sidebar Toggle
    const sidebarToggle = document.getElementById('sidebar-toggle');
    const sidebar = document.querySelector('.dashboard-sidebar');
    if (sidebarToggle && sidebar) {
        sidebarToggle.addEventListener('click', () => {
            sidebar.classList.toggle('active');
        });
    }
    
    // Live Data Updates
    setInterval(updateLiveStats, 5000);
}

// Utility Functions
function getLastNHours(n) {
    const hours = [];
    for (let i = n - 1; i >= 0; i--) {
        const d = new Date();
        d.setHours(d.getHours() - i);
        hours.push(d.getHours() + ':00');
    }
    return hours;
}

function generateRandomData(n) {
    return Array.from({length: n}, () => Math.floor(Math.random() * 100));
}

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

// Live Data Updates
function updateLiveStats() {
    fetch('/api/stats')
        .then(response => response.json())
        .then(data => {
            // Update connection status
            const statusIndicator = document.querySelector('.status-indicator');
            if (statusIndicator) {
                statusIndicator.className = `status-indicator ${data.isConnected ? 'online' : 'offline'}`;
                statusIndicator.textContent = data.isConnected ? 'Connected' : 'Disconnected';
            }
            
            // Update traffic stats
            const uploadStat = document.getElementById('upload-stat');
            const downloadStat = document.getElementById('download-stat');
            if (uploadStat) uploadStat.textContent = formatBytes(data.uploadTotal);
            if (downloadStat) downloadStat.textContent = formatBytes(data.downloadTotal);
            
            // Update active sessions
            updateSessionsList(data.sessions);
        })
        .catch(console.error);
}

function updateSessionsList(sessions) {
    const sessionsList = document.getElementById('active-sessions');
    if (!sessionsList) return;
    
    sessions.forEach(session => {
        const existingSession = document.getElementById(`session-${session.id}`);
        if (!existingSession) {
            // Create new session card
            const sessionCard = createSessionCard(session);
            animate.slideIn(sessionCard, 'right');
            sessionsList.appendChild(sessionCard);
        } else {
            // Update existing session
            updateSessionCard(existingSession, session);
        }
    });
}

function createSessionCard(session) {
    const card = document.createElement('div');
    card.id = `session-${session.id}`;
    card.className = 'session-card dashboard-card';
    card.innerHTML = `
        <div class="session-info">
            <h6 class="mb-1">${session.protocol}</h6>
            <small class="text-muted">${session.ip}</small>
        </div>
        <div class="session-stats">
            <div class="mb-1">↑ ${formatBytes(session.upload)}</div>
            <div>↓ ${formatBytes(session.download)}</div>
        </div>
    `;
    return card;
}

function updateSessionCard(card, session) {
    const uploadEl = card.querySelector('.session-stats div:first-child');
    const downloadEl = card.querySelector('.session-stats div:last-child');
    
    uploadEl.textContent = `↑ ${formatBytes(session.upload)}`;
    downloadEl.textContent = `↓ ${formatBytes(session.download)}`;
}