// Main application initialization and global functionality

// Application state
const app = {
    initialized: false,
    currentPage: 'home',
    version: '1.0.0'
};

// Initialize the application
document.addEventListener('DOMContentLoaded', () => {
    console.log('SeReact Frontend v' + app.version + ' - Initializing...');
    
    // Initialize configuration
    initializeApp();
    
    // Set up global event listeners
    setupGlobalEventListeners();
    
    // Check initial configuration state
    checkInitialConfiguration();
    
    app.initialized = true;
    console.log('SeReact Frontend - Initialization complete');
});

// Initialize the application
function initializeApp() {
    // Update navigation state based on configuration
    updateNavigationState();
    
    // Initialize page routing
    initializeRouting();
    
    // Set up periodic health checks
    setupHealthChecks();
    
    // Initialize keyboard shortcuts
    setupKeyboardShortcuts();
}

// Set up global event listeners
function setupGlobalEventListeners() {
    // Handle online/offline status
    window.addEventListener('online', () => {
        showAlert('Connection restored', 'success');
        updateConnectionStatus(true);
    });
    
    window.addEventListener('offline', () => {
        showAlert('Connection lost - working offline', 'warning', true);
        updateConnectionStatus(false);
    });
    
    // Handle visibility changes (tab switching)
    document.addEventListener('visibilitychange', () => {
        if (!document.hidden && config.isConfigured()) {
            // Refresh current page data when tab becomes visible
            refreshCurrentPageData();
        }
    });
    
    // Handle window resize
    window.addEventListener('resize', debounce(() => {
        handleWindowResize();
    }, 250));
    
    // Handle beforeunload for unsaved changes warning
    window.addEventListener('beforeunload', (e) => {
        if (hasUnsavedChanges()) {
            e.preventDefault();
            e.returnValue = '';
        }
    });
}

// Check initial configuration
function checkInitialConfiguration() {
    if (!config.isConfigured()) {
        // Show welcome message for first-time users
        setTimeout(() => {
            showWelcomeMessage();
        }, 1000);
    } else {
        // Test connection on startup
        setTimeout(() => {
            testConnectionSilently();
        }, 500);
    }
}

// Show welcome message for new users
function showWelcomeMessage() {
    const modalBody = `
        <div class="text-center mb-4">
            <i class="fas fa-rocket fa-3x text-primary mb-3"></i>
            <h4>Welcome to SeReact!</h4>
            <p class="lead">AI-powered image management and semantic search platform</p>
        </div>
        
        <div class="row">
            <div class="col-md-6">
                <div class="card h-100">
                    <div class="card-body text-center">
                        <i class="fas fa-cog fa-2x text-primary mb-3"></i>
                        <h6>Configure API</h6>
                        <p class="small">Set up your API connection to get started</p>
                    </div>
                </div>
            </div>
            <div class="col-md-6">
                <div class="card h-100">
                    <div class="card-body text-center">
                        <i class="fas fa-upload fa-2x text-success mb-3"></i>
                        <h6>Upload Images</h6>
                        <p class="small">Start building your image collection</p>
                    </div>
                </div>
            </div>
        </div>
        
        <div class="mt-4 text-center">
            <p class="text-muted">Ready to begin? Let's configure your API connection first.</p>
        </div>
    `;

    const modalFooter = `
        <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Maybe Later</button>
        <button type="button" class="btn btn-primary" onclick="showPage('config')" data-bs-dismiss="modal">
            <i class="fas fa-cog me-1"></i>Configure Now
        </button>
    `;

    const modal = createModal('welcomeModal', 'Welcome to SeReact', modalBody, modalFooter);
    modal.show();
}

// Test connection silently (without showing alerts)
async function testConnectionSilently() {
    try {
        const isHealthy = await apiClient.healthCheck();
        updateConnectionStatus(isHealthy);
    } catch (error) {
        updateConnectionStatus(false);
    }
}

// Update connection status indicator
function updateConnectionStatus(isOnline) {
    // Add a connection status indicator to the navbar
    let statusIndicator = document.getElementById('connectionStatus');
    
    if (!statusIndicator) {
        statusIndicator = document.createElement('div');
        statusIndicator.id = 'connectionStatus';
        statusIndicator.className = 'nav-item';
        
        const navbar = document.querySelector('.navbar-nav');
        if (navbar) {
            navbar.appendChild(statusIndicator);
        }
    }
    
    statusIndicator.innerHTML = `
        <span class="nav-link">
            <i class="fas fa-circle ${isOnline ? 'status-online' : 'status-offline'}" 
               title="${isOnline ? 'Connected' : 'Disconnected'}"></i>
        </span>
    `;
}

// Initialize routing
function initializeRouting() {
    // Handle hash changes for deep linking
    window.addEventListener('hashchange', handleRouteChange);
    
    // Handle initial route
    handleRouteChange();
}

// Handle route changes
function handleRouteChange() {
    const hash = window.location.hash.substring(1);
    const route = hash || 'home';
    
    // Validate route
    const validRoutes = ['home', 'config', 'images', 'search', 'teams', 'users', 'api-keys'];
    
    if (validRoutes.includes(route)) {
        showPage(route);
    } else {
        // Invalid route, redirect to home
        window.location.hash = 'home';
    }
}

// Set up periodic health checks
function setupHealthChecks() {
    if (!config.isConfigured()) return;
    
    // Check health every 5 minutes
    setInterval(async () => {
        if (config.isConfigured() && navigator.onLine) {
            try {
                const isHealthy = await apiClient.healthCheck();
                updateConnectionStatus(isHealthy);
            } catch (error) {
                updateConnectionStatus(false);
            }
        }
    }, 5 * 60 * 1000);
}

// Set up keyboard shortcuts
function setupKeyboardShortcuts() {
    document.addEventListener('keydown', (e) => {
        // Only handle shortcuts when not in input fields
        if (e.target.tagName === 'INPUT' || e.target.tagName === 'TEXTAREA') {
            return;
        }
        
        // Ctrl/Cmd + shortcuts
        if (e.ctrlKey || e.metaKey) {
            switch (e.key) {
                case 'k':
                    e.preventDefault();
                    showPage('search');
                    setTimeout(() => {
                        const searchInput = document.getElementById('searchQuery');
                        if (searchInput) searchInput.focus();
                    }, 100);
                    break;
                case 'u':
                    e.preventDefault();
                    if (app.currentPage === 'images') {
                        showUploadModal();
                    } else {
                        showPage('images');
                        setTimeout(() => showUploadModal(), 100);
                    }
                    break;
                case ',':
                    e.preventDefault();
                    showPage('config');
                    break;
            }
        }
        
        // Number shortcuts for navigation
        if (e.key >= '1' && e.key <= '6' && !e.ctrlKey && !e.metaKey && !e.altKey) {
            const pages = ['home', 'images', 'search', 'teams', 'users', 'api-keys'];
            const pageIndex = parseInt(e.key) - 1;
            if (pages[pageIndex]) {
                e.preventDefault();
                showPage(pages[pageIndex]);
            }
        }
        
        // Escape key to close modals
        if (e.key === 'Escape') {
            const openModals = document.querySelectorAll('.modal.show');
            openModals.forEach(modal => {
                const bsModal = bootstrap.Modal.getInstance(modal);
                if (bsModal) bsModal.hide();
            });
        }
    });
}

// Refresh current page data
function refreshCurrentPageData() {
    switch (app.currentPage) {
        case 'images':
            loadImages(currentPage);
            break;
        case 'teams':
            loadTeams();
            break;
        case 'users':
            loadUsers();
            break;
        case 'api-keys':
            loadApiKeys();
            break;
    }
}

// Handle window resize
function handleWindowResize() {
    // Reinitialize tooltips and popovers after resize
    initializeTooltips();
    initializePopovers();
    
    // Adjust image grid if on images page
    if (app.currentPage === 'images') {
        // Force reflow of image grid
        const imageGrid = document.querySelector('.image-grid');
        if (imageGrid) {
            imageGrid.style.display = 'none';
            imageGrid.offsetHeight; // Trigger reflow
            imageGrid.style.display = 'grid';
        }
    }
}

// Check for unsaved changes
function hasUnsavedChanges() {
    // Check if any forms have been modified
    const forms = document.querySelectorAll('form');
    for (const form of forms) {
        if (form.dataset.modified === 'true') {
            return true;
        }
    }
    return false;
}

// Mark form as modified
function markFormAsModified(formElement) {
    formElement.dataset.modified = 'true';
}

// Mark form as saved
function markFormAsSaved(formElement) {
    formElement.dataset.modified = 'false';
}

// Global error handler
window.addEventListener('error', (e) => {
    console.error('Global error:', e.error);
    
    // Don't show alerts for network errors or script loading errors
    if (e.error && !e.error.message.includes('Loading')) {
        showAlert('An unexpected error occurred. Please refresh the page if problems persist.', 'danger');
    }
});

// Global unhandled promise rejection handler
window.addEventListener('unhandledrejection', (e) => {
    console.error('Unhandled promise rejection:', e.reason);
    
    // Don't show alerts for network-related rejections
    if (e.reason && !e.reason.message?.includes('fetch')) {
        showAlert('An unexpected error occurred. Please try again.', 'danger');
    }
    
    // Prevent the default browser behavior
    e.preventDefault();
});

// Export app object for debugging
window.SeReactApp = app;

// Add helpful console messages
console.log('%cSeReact Frontend', 'color: #0d6efd; font-size: 24px; font-weight: bold;');
console.log('%cVersion: ' + app.version, 'color: #6c757d; font-size: 14px;');
console.log('%cKeyboard Shortcuts:', 'color: #198754; font-size: 16px; font-weight: bold;');
console.log('%c  Ctrl+K: Search', 'color: #6c757d;');
console.log('%c  Ctrl+U: Upload Image', 'color: #6c757d;');
console.log('%c  Ctrl+,: Settings', 'color: #6c757d;');
console.log('%c  1-6: Navigate to pages', 'color: #6c757d;');
console.log('%c  Esc: Close modals', 'color: #6c757d;');