/**
 * Embryo Grading System - Main Application Entry Point
 * Modular structure for better debugging and maintenance
 */

import { initONNXRuntime, loadLabelMappings, loadAllModels } from './models/modelLoader.js';
import { setupEventListeners } from './ui/eventHandlers.js';
import { updateLoadingStatus, hideLoading } from './ui/loading.js';
import { showToast } from './ui/toast.js';
import { initializeStepper } from './ui/stepper.js';
import { initializeCropEditor } from './ui/cropEditor.js';
import { onAuthChange, signOutUser, getCurrentUser } from './utils/firebaseService.js';

/**
 * Check authentication status
 */
function checkAuthentication() {
    return new Promise((resolve) => {
        onAuthChange((user) => {
            if (user) {
                // User is logged in
                const userEmail = document.getElementById('userEmail');
                const userMenu = document.getElementById('userMenu');
                
                if (userEmail) {
                    userEmail.textContent = user.email;
                }
                if (userMenu) {
                    userMenu.style.display = 'flex';
                }
                
                resolve(true);
            } else {
                // User is not logged in, redirect to login
                if (window.location.pathname !== '/login.html' && !window.location.pathname.endsWith('login.html')) {
                    window.location.href = '/login.html';
                }
                resolve(false);
            }
        });
    });
}

/**
 * Setup logout functionality
 */
function setupLogout() {
    const logoutBtn = document.getElementById('logoutBtn');
    if (logoutBtn) {
        logoutBtn.addEventListener('click', async () => {
            try {
                await signOutUser();
                window.location.href = '/'; // Redirect to root which serves login.html
            } catch (error) {
                console.error('Logout error:', error);
                showToast('Failed to logout', 'error');
            }
        });
    }
}

/**
 * Initialize the application
 */
async function init() {
    try {
        // Auto-logout on page refresh/reload
        // Check if this is a page reload (not initial load from login)
        const isPageReload = performance.navigation.type === 1 || 
                            performance.getEntriesByType('navigation')[0]?.type === 'reload';
        
        if (isPageReload) {
            // Page was reloaded, logout and redirect to login
            try {
                await signOutUser();
            } catch (error) {
                console.error('Auto-logout error:', error);
            }
            window.location.href = '/';
            return;
        }
        
        // Check authentication first
        const isAuthenticated = await checkAuthentication();
        if (!isAuthenticated) {
            return; // Will redirect to login
        }
        
        // Setup logout
        setupLogout();
        
        updateLoadingStatus('Initializing ONNX Runtime...', 10);
        
        // Configure ONNX Runtime
        await initONNXRuntime();
        
        // Load label mappings
        await loadLabelMappings();
        
        // Load models
        await loadAllModels();
        
        // Setup UI event listeners
        setupEventListeners();
        
        // Initialize stepper
        initializeStepper();
        
        // Initialize crop editor
        initializeCropEditor();
        
        // Hide loading overlay
        hideLoading();
        
        showToast('AI models loaded successfully!', 'success');
    } catch (error) {
        console.error('Initialization error:', error);
        showToast(`Initialization failed: ${error.message}`, 'error');
        updateLoadingStatus(`Error: ${error.message}`, 100);
    }
}

// Initialize app when DOM is loaded
if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
} else {
    init();
}

export { init };