document.addEventListener('DOMContentLoaded', function() {
    // UI Elements
    const splashScreen = document.getElementById('splashScreen');
    const mainContent = document.getElementById('mainContent');
    const fileModal = document.getElementById('fileModal');
    const modalTitle = document.getElementById('modalTitle');
    const fileInput = document.getElementById('fileInput');
    const cancelBtn = document.getElementById('cancelBtn');
    const confirmBtn = document.getElementById('confirmBtn');
    
    // Button handlers
    document.getElementById('loadConfig').addEventListener('click', () => showFileModal('Настройка'));
    document.getElementById('load1C').addEventListener('click', () => showFileModal('1C Data'));
    document.getElementById('loadFlight').addEventListener('click', () => showFileModal('Flight Data'));
    document.getElementById('loadPosition').addEventListener('click', () => showFileModal('Position Data'));
    document.getElementById('continueBtn').addEventListener('click', continueToMain);
    document.getElementById('exitBtn').addEventListener('click', exitApp);
    
    cancelBtn.addEventListener('click', closeFileModal);
    confirmBtn.addEventListener('click', processFile);
    
    function showFileModal(title) {
        modalTitle.textContent = `Загрузка файла ${title}`;
        fileInput.value = '';
        fileModal.style.display = 'flex';
    }
    
    function closeFileModal() {
        fileModal.style.display = 'none';
    }
    
    function processFile() {
        const file = fileInput.files[0];
        if (!file) return;
        
        // Here we would process the file based on the modal title
        const reader = new FileReader();
        reader.onload = function(e) {
            const data = new Uint8Array(e.target.result);
            const workbook = XLSX.read(data, { type: 'array' });
            
            // Process workbook based on file type
            // TODO: Add specific processing for each file type
            closeFileModal();
        };
        reader.readAsArrayBuffer(file);
    }
    
    function continueToMain() {
        splashScreen.style.display = 'none';
        mainContent.style.display = 'flex';
        // Load initial data here
    }
    
    function exitApp() {
        if (confirm('Вы уверены, что хотите выйти?')) {
            window.close();
        }
    }
    
    // Initialize database
    if (!window.localStorage.getItem('employeeDB')) {
        window.localStorage.setItem('employeeDB', JSON.stringify({
            employees: [],
            lastUpdate: new Date().toISOString()
        }));
    }
});