// PDF Editor - Main JavaScript Functions

// Global variables
let uploadedFiles = [];
let sortableInstance = null;

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

function getFileIcon(filename) {
    const extension = filename.toLowerCase().split('.').pop();
    const iconMap = {
        'pdf': 'fas fa-file-pdf text-danger',
        'jpg': 'fas fa-file-image text-success',
        'jpeg': 'fas fa-file-image text-success',
        'png': 'fas fa-file-image text-success',
        'gif': 'fas fa-file-image text-success',
        'bmp': 'fas fa-file-image text-success',
        'tiff': 'fas fa-file-image text-success',
        'zip': 'fas fa-file-archive text-warning'
    };
    return iconMap[extension] || 'fas fa-file text-muted';
}

// Show notification
function showNotification(message, type = 'info') {
    // Create notification element
    const notification = document.createElement('div');
    notification.className = `alert alert-${type} alert-dismissible fade show position-fixed`;
    notification.style.cssText = 'top: 20px; right: 20px; z-index: 9999; max-width: 400px;';
    notification.innerHTML = `
        ${message}
        <button type="button" class="btn-close" data-bs-dismiss="alert"></button>
    `;
    
    document.body.appendChild(notification);
    
    // Auto remove after 5 seconds
    setTimeout(() => {
        if (notification.parentNode) {
            notification.remove();
        }
    }, 5000);
}

// Show/hide loading state
function setLoadingState(element, loading = true) {
    if (loading) {
        element.disabled = true;
        const originalText = element.innerHTML;
        element.dataset.originalText = originalText;
        element.innerHTML = '<i class="fas fa-spinner fa-spin me-2"></i>Verarbeitung...';
    } else {
        element.disabled = false;
        element.innerHTML = element.dataset.originalText || element.innerHTML;
    }
}

// AJAX helper function
async function makeRequest(url, options = {}) {
    try {
        const response = await fetch(url, {
            headers: {
                'Content-Type': 'application/json',
                ...options.headers
            },
            ...options
        });
        
        if (!response.ok) {
            throw new Error(`HTTP error! status: ${response.status}`);
        }
        
        return await response.json();
    } catch (error) {
        console.error('Request failed:', error);
        throw error;
    }
}

// File upload with progress
async function uploadFiles(files, endpoint, progressCallback) {
    const formData = new FormData();
    
    if (Array.isArray(files)) {
        files.forEach(file => formData.append('files', file));
    } else {
        formData.append('file', files);
    }
    
    return new Promise((resolve, reject) => {
        const xhr = new XMLHttpRequest();
        
        // Upload progress
        xhr.upload.addEventListener('progress', (e) => {
            if (e.lengthComputable && progressCallback) {
                const percentComplete = (e.loaded / e.total) * 100;
                progressCallback(percentComplete);
            }
        });
        
        xhr.addEventListener('load', () => {
            if (xhr.status === 200) {
                try {
                    const response = JSON.parse(xhr.responseText);
                    resolve(response);
                } catch (error) {
                    reject(new Error('Invalid JSON response'));
                }
            } else {
                reject(new Error(`Upload failed with status: ${xhr.status}`));
            }
        });
        
        xhr.addEventListener('error', () => {
            reject(new Error('Upload failed'));
        });
        
        xhr.open('POST', endpoint);
        xhr.send(formData);
    });
}

// Drag and drop functionality
function setupDragAndDrop(element, callback) {
    ['dragenter', 'dragover', 'dragleave', 'drop'].forEach(eventName => {
        element.addEventListener(eventName, preventDefaults, false);
    });
    
    function preventDefaults(e) {
        e.preventDefault();
        e.stopPropagation();
    }
    
    ['dragenter', 'dragover'].forEach(eventName => {
        element.addEventListener(eventName, () => {
            element.classList.add('dragover');
        }, false);
    });
    
    ['dragleave', 'drop'].forEach(eventName => {
        element.addEventListener(eventName, () => {
            element.classList.remove('dragover');
        }, false);
    });
    
    element.addEventListener('drop', (e) => {
        const files = Array.from(e.dataTransfer.files);
        callback(files);
    }, false);
}

// Sortable list functionality
function setupSortable(container, onUpdate) {
    if (typeof Sortable !== 'undefined') {
        return Sortable.create(container, {
            animation: 150,
            ghostClass: 'sortable-ghost',
            chosenClass: 'sortable-chosen',
            dragClass: 'sortable-drag',
            onUpdate: onUpdate
        });
    }
    return null;
}

// Initialize tooltips
function initializeTooltips() {
    const tooltipTriggerList = [].slice.call(document.querySelectorAll('[data-bs-toggle="tooltip"]'));
    tooltipTriggerList.map(function (tooltipTriggerEl) {
        return new bootstrap.Tooltip(tooltipTriggerEl);
    });
}

// Initialize on page load
document.addEventListener('DOMContentLoaded', function() {
    initializeTooltips();
    
    // Add fade-in animation to main content
    const mainContent = document.querySelector('main');
    if (mainContent) {
        mainContent.classList.add('fade-in');
    }
});