/**
 * Simple WYSIWYG Editor
 * Lightweight rich text editor for publication content
 */

class WYSIWYGEditor {
    constructor(textareaId, options = {}) {
        this.textarea = document.getElementById(textareaId);
        this.options = {
            toolbar: ['bold', 'italic', 'underline', '|', 'link', 'image', '|', 'ul', 'ol', '|', 'h1', 'h2', 'h3'],
            ...options
        };
        
        this.selectedImages = [];
        
        this.createEditor();
        this.bindEvents();
        this.setupImageUpload();
    }
    
    createEditor() {
        // Create editor container
        this.container = document.createElement('div');
        this.container.className = 'wysiwyg-container';
        
        // Create toolbar
        this.toolbar = document.createElement('div');
        this.toolbar.className = 'wysiwyg-toolbar';
        this.createToolbarButtons();
        
        // Create content area
        this.content = document.createElement('div');
        this.content.className = 'wysiwyg-content';
        this.content.contentEditable = true;
        
        // Create character count
        this.charCount = document.createElement('div');
        this.charCount.className = 'wysiwyg-char-count';
        
        // Assemble editor
        this.container.appendChild(this.toolbar);
        this.container.appendChild(this.content);
        this.container.appendChild(this.charCount);
        
        // Replace textarea
        this.textarea.parentNode.insertBefore(this.container, this.textarea);
        this.textarea.style.display = 'none';
        
        // Initialize content
        this.content.innerHTML = this.textarea.value;
        this.updateCharCount();
    }
    
    createToolbarButtons() {
        this.options.toolbar.forEach(item => {
            if (item === '|') {
                const separator = document.createElement('div');
                separator.className = 'wysiwyg-separator';
                this.toolbar.appendChild(separator);
            } else {
                const button = document.createElement('button');
                button.className = 'wysiwyg-btn';
                button.type = 'button';
                button.innerHTML = this.getButtonLabel(item);
                button.dataset.command = item;
                
                button.addEventListener('click', () => this.execCommand(item));
                this.toolbar.appendChild(button);
            }
        });
    }
    
    getButtonLabel(command) {
        const labels = {
            'bold': 'B',
            'italic': 'I',
            'underline': 'U',
            'link': '🔗',
            'image': '🖼️',
            'ul': '• List',
            'ol': '1. List',
            'h1': 'H1',
            'h2': 'H2',
            'h3': 'H3'
        };
        return labels[command] || command;
    }
    
    execCommand(command) {
        switch (command) {
            case 'bold':
                document.execCommand('bold', false, null);
                break;
            case 'italic':
                document.execCommand('italic', false, null);
                break;
            case 'underline':
                document.execCommand('underline', false, null);
                break;
            case 'link':
                this.insertLink();
                break;
            case 'image':
                this.insertImage();
                break;
            case 'ul':
                document.execCommand('insertUnorderedList', false, null);
                break;
            case 'ol':
                document.execCommand('insertOrderedList', false, null);
                break;
            case 'h1':
                this.formatHeading('h1');
                break;
            case 'h2':
                this.formatHeading('h2');
                break;
            case 'h3':
                this.formatHeading('h3');
                break;
        }
        
        this.content.focus();
    }
    
    insertLink() {
        const selection = window.getSelection();
        const url = prompt('Enter URL:');
        if (url) {
            document.execCommand('createLink', false, url);
        }
    }
    
    insertImage() {
        this.openImageGallery();
    }
    
    openImageGallery() {
        this.selectedImages = [];
        this.loadGalleryImages();
        document.getElementById('imageGallery').classList.add('open');
    }
    
    closeImageGallery() {
        document.getElementById('imageGallery').classList.remove('open');
        this.selectedImages = [];
        this.updateInsertButton();
    }
    
    showGalleryTab(tab) {
        // Hide all tabs
        document.getElementById('galleryBrowse').style.display = 'none';
        document.getElementById('galleryUpload').style.display = 'none';
        
        // Remove active class from all tabs
        document.querySelectorAll('.gallery-tab').forEach(tab => {
            tab.classList.remove('active');
        });
        
        // Show selected tab and add active class
        if (tab === 'browse') {
            document.getElementById('galleryBrowse').style.display = 'block';
            document.querySelectorAll('.gallery-tab')[0].classList.add('active');
        } else if (tab === 'upload') {
            document.getElementById('galleryUpload').style.display = 'block';
            document.querySelectorAll('.gallery-tab')[1].classList.add('active');
        }
    }
    
    async loadGalleryImages() {
        try {
            const response = await fetch('upload_image.php');
            const data = await response.json();
            
            if (data.success) {
                this.renderGalleryImages(data.images);
            } else {
                console.error('Failed to load images:', data.error);
            }
        } catch (error) {
            console.error('Error loading images:', error);
        }
    }
    
    renderGalleryImages(images) {
        const grid = document.getElementById('galleryGrid');
        grid.innerHTML = '';
        
        images.forEach(image => {
            const item = document.createElement('div');
            item.className = 'gallery-item';
            item.dataset.imageId = image.id;
            item.dataset.imageUrl = image.url;
            item.dataset.imageName = image.original_name;
            
            item.innerHTML = `
                <img src="${image.thumbnail_url}" alt="${image.original_name}" class="gallery-image">
                <div class="gallery-info">
                    <div class="gallery-name">${image.original_name}</div>
                    <div class="gallery-size">${this.formatFileSize(image.size)}</div>
                </div>
            `;
            
            item.addEventListener('click', () => this.selectImage(item));
            grid.appendChild(item);
        });
    }
    
    selectImage(item) {
        const imageId = item.dataset.imageId;
        
        if (item.classList.contains('selected')) {
            item.classList.remove('selected');
            this.selectedImages = this.selectedImages.filter(id => id !== imageId);
        } else {
            item.classList.add('selected');
            this.selectedImages.push(imageId);
        }
        
        this.updateInsertButton();
    }
    
    updateInsertButton() {
        const insertBtn = document.getElementById('galleryInsertBtn');
        insertBtn.disabled = this.selectedImages.length === 0;
    }
    
    insertSelectedImage() {
        if (this.selectedImages.length === 0) return;
        
        const selectedItems = document.querySelectorAll('.gallery-item.selected');
        const images = [];
        
        selectedItems.forEach(item => {
            images.push({
                url: item.dataset.imageUrl,
                name: item.dataset.imageName
            });
        });
        
        // Insert images into editor
        images.forEach(image => {
            const img = document.createElement('img');
            img.src = image.url;
            img.alt = image.name;
            img.style.maxWidth = '100%';
            img.style.height = 'auto';
            
            // Insert at cursor position
            const selection = window.getSelection();
            if (selection.rangeCount > 0) {
                const range = selection.getRangeAt(0);
                range.insertNode(img);
                range.collapse(false);
            } else {
                this.content.appendChild(img);
            }
        });
        
        // Update textarea and close gallery
        this.textarea.value = this.content.innerHTML;
        this.closeImageGallery();
    }
    
    setupImageUpload() {
        const uploadArea = document.getElementById('uploadArea');
        const fileInput = document.getElementById('fileInput');
        
        // Click to upload
        uploadArea.addEventListener('click', () => {
            fileInput.click();
        });
        
        // File selection
        fileInput.addEventListener('change', (e) => {
            this.handleFileUpload(e.target.files);
        });
        
        // Drag and drop
        uploadArea.addEventListener('dragover', (e) => {
            e.preventDefault();
            uploadArea.classList.add('dragover');
        });
        
        uploadArea.addEventListener('dragleave', () => {
            uploadArea.classList.remove('dragover');
        });
        
        uploadArea.addEventListener('drop', (e) => {
            e.preventDefault();
            uploadArea.classList.remove('dragover');
            this.handleFileUpload(e.dataTransfer.files);
        });
    }
    
    async handleFileUpload(files) {
        const formData = new FormData();
        
        for (let i = 0; i < files.length; i++) {
            formData.append('images[]', files[i]);
        }
        
        try {
            this.showUploadProgress();
            
            const response = await fetch('upload_image.php', {
                method: 'POST',
                body: formData
            });
            
            const data = await response.json();
            
            if (data.success) {
                this.showUploadSuccess('Images uploaded successfully!');
                // Refresh gallery
                this.loadGalleryImages();
                // Switch to browse tab
                this.showGalleryTab('browse');
            } else {
                this.showUploadError('Upload failed: ' + data.errors.join(', '));
            }
        } catch (error) {
            this.showUploadError('Upload failed: ' + error.message);
        } finally {
            this.hideUploadProgress();
        }
    }
    
    showUploadProgress() {
        document.getElementById('uploadProgress').classList.add('active');
        document.getElementById('uploadStatus').textContent = 'Uploading...';
        document.getElementById('progressFill').style.width = '50%';
    }
    
    hideUploadProgress() {
        document.getElementById('uploadProgress').classList.remove('active');
        document.getElementById('progressFill').style.width = '0%';
    }
    
    showUploadSuccess(message) {
        const status = document.getElementById('uploadStatus');
        status.textContent = message;
        status.className = 'upload-status success';
        
        setTimeout(() => {
            this.hideUploadProgress();
        }, 3000);
    }
    
    showUploadError(message) {
        const status = document.getElementById('uploadStatus');
        status.textContent = message;
        status.className = 'upload-status error';
        
        setTimeout(() => {
            this.hideUploadProgress();
        }, 5000);
    }
    
    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];
    }
    
    formatHeading(tag) {
        const selection = window.getSelection();
        const range = selection.getRangeAt(0);
        const heading = document.createElement(tag);
        heading.textContent = range.toString();
        range.deleteContents();
        range.insertNode(heading);
    }
    
    bindEvents() {
        // Update textarea when content changes
        this.content.addEventListener('input', () => {
            this.textarea.value = this.content.innerHTML;
            this.updateCharCount();
        });
        
        // Update content when textarea changes (for form submission)
        this.textarea.addEventListener('input', () => {
            this.content.innerHTML = this.textarea.value;
            this.updateCharCount();
        });
        
        // Handle paste events
        this.content.addEventListener('paste', (e) => {
            e.preventDefault();
            const text = e.clipboardData.getData('text/html') || e.clipboardData.getData('text/plain');
            document.execCommand('insertHTML', false, text);
        });
        
        // Keyboard shortcuts
        this.content.addEventListener('keydown', (e) => {
            if (e.ctrlKey || e.metaKey) {
                switch (e.key) {
                    case 'b':
                        e.preventDefault();
                        this.execCommand('bold');
                        break;
                    case 'i':
                        e.preventDefault();
                        this.execCommand('italic');
                        break;
                    case 'u':
                        e.preventDefault();
                        this.execCommand('underline');
                        break;
                }
            }
        });
    }
    
    updateCharCount() {
        const text = this.content.innerText || this.content.textContent || '';
        const count = text.length;
        this.charCount.textContent = `Characters: ${count}`;
    }
    
    getContent() {
        return this.content.innerHTML;
    }
    
    setContent(html) {
        this.content.innerHTML = html;
        this.textarea.value = html;
        this.updateCharCount();
    }
    
    destroy() {
        this.textarea.style.display = 'block';
        this.textarea.value = this.content.innerHTML;
        this.container.remove();
    }
}

// Initialize editor when DOM is ready
document.addEventListener('DOMContentLoaded', () => {
    const editor = new WYSIWYGEditor('content');
    
    // Make editor globally accessible
    window.wysiwygEditor = editor;
    
    // Handle form submission
    const form = document.querySelector('.publication-form');
    if (form) {
        form.addEventListener('submit', () => {
            // Ensure textarea has latest content
            document.getElementById('content').value = editor.getContent();
        });
    }
});