document.addEventListener('DOMContentLoaded', function() {
    const templateUpload = document.getElementById('templateUpload');
    const uploadTemplateBtn = document.getElementById('uploadTemplateBtn');
    const scanPdfBtn = document.getElementById('scanPdfBtn');
    const previewPdfBtn = document.getElementById('previewPdfBtn');
const csvPreview = document.getElementById('csvPreview');
    const rowSelection = document.getElementById('rowSelection');
    const generatePdfBtn = document.getElementById('generatePdfBtn');
    const downloadSection = document.getElementById('downloadSection');
    const downloadLink = document.getElementById('downloadLink');
    let csvData = [];
    let headers = [];
    let pdfDoc = null;
    let pdfFields = [];

    // Handle template PDF locally
    uploadTemplateBtn.addEventListener('click', async () => {
        let file;
        const localPathInput = document.getElementById('localPath');
        
        if (localPathInput.value) {
            try {
                // Handle local path input
                if (!localPathInput.value.startsWith('http') && !localPathInput.value.startsWith('file://')) {
                    alert('Local paths must start with "file://" (e.g., file:///C:/path/to/file.pdf)');
                    return;
                }
                
                const response = await fetch(localPathInput.value, {
                    mode: 'cors',
                    headers: {
                        'Content-Type': 'application/pdf'
                    }
                });
                
                if (!response.ok) {
                    throw new Error(`HTTP error! status: ${response.status}`);
                }
                
                const blob = await response.blob();
                if (blob.size === 0) {
                    throw new Error('Empty file received');
                }
                
                file = new File([blob], localPathInput.value.split('/').pop() || 'document.pdf', { type: 'application/pdf' });
            } catch (error) {
                console.error('File loading error:', error);
                alert(`Error loading file: ${error.message}\n\nMake sure:\n1. Path starts with file://\n2. File exists\n3. CORS is enabled for local files`);
                return;
            }
} else if (templateUpload.files.length) {
            file = templateUpload.files[0];
        } else {
            alert('Please select a PDF file or enter a local path first');
            return;
        }
const today = new Date();
        const dateString = `${today.getFullYear()}-${String(today.getMonth() + 1).padStart(2, '0')}-${String(today.getDate()).padStart(2, '0')}`;
        
        try {
            // Initialize PDF.js
pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/2.12.313/pdf.worker.min.js';
const fileHandle = await todayDirHandle.getFileHandle(file.name, { create: true });
                const writable = await fileHandle.createWritable();
                await writable.write(file);
                await writable.close();
            });
            
            // Display PDF preview
            const pdfViewer = document.getElementById('pdfViewer');
            pdfViewer.src = URL.createObjectURL(file);
            // Load PDF and extract form fields
            const fileReader = new FileReader();
            fileReader.onload = async function() {
                const typedArray = new Uint8Array(this.result);
                pdfDoc = await pdfjsLib.getDocument(typedArray).promise;
                
                // Get form fields (this is a simplified approach)
                const page = await pdfDoc.getPage(1);
                const textContent = await page.getTextContent();
                const textItems = textContent.items.map(item => item.str);
                
                // Filter out empty strings and common PDF text
                pdfFields = textItems.filter(text => 
                    text.trim().length > 0 && 
                    !text.match(/page|©|http|www|\.com|\.org|\.net/i)
                );
                
                // Display found fields
                const fieldsList = document.getElementById('invoiceFieldsList');
                fieldsList.innerHTML = '';
                
                pdfFields.forEach(field => {
                    const li = document.createElement('li');
                    li.className = 'list-group-item';
                    li.textContent = field;
                    fieldsList.appendChild(li);
                });
                
                // Show the fields section
                document.getElementById('pdfPreview').classList.remove('d-none');
            };
            fileReader.readAsArrayBuffer(file);
} catch (error) {
            console.error('Error uploading template:', error);
            alert('Failed to upload template');
        }
    });

    // Add new field functionality
    document.getElementById('addFieldBtn').addEventListener('click', () => {
        const nameInput = document.getElementById('newFieldName');
        const valueInput = document.getElementById('newFieldValue');
        const fieldsList = document.getElementById('newFieldsList');
        
        if (!nameInput.value.trim()) {
            alert('Please enter a field name');
            return;
        }
        
        const fieldItem = document.createElement('div');
        fieldItem.className = 'list-group-item d-flex justify-content-between align-items-center';
        fieldItem.innerHTML = `
            <span><strong>${nameInput.value}:</strong> ${valueInput.value}</span>
            <button class="btn btn-sm btn-danger remove-field">×</button>
        `;
        
        fieldsList.appendChild(fieldItem);
        
        // Clear inputs
        nameInput.value = '';
        valueInput.value = '';
        
        // Add remove functionality
        fieldItem.querySelector('.remove-field').addEventListener('click', () => {
            fieldItem.remove();
        });
    });
    // Handle PDF scanning
    scanPdfBtn.addEventListener('click', async () => {
        if (!pdfDoc) {
            alert('Please upload and process a PDF file first');
            return;
        }

        // Extract common invoice fields (simplified example)
        const invoiceNumber = pdfFields.find(field => 
            field.match(/invoice|מספר|חשבונית|מספר חשבונית/i)
        );
        const dateField = pdfFields.find(field => 
            field.match(/date|תאריך|date issued/i)
        );
        const reasonField = pdfFields.find(field => 
            field.match(/treatment|reason|service|סוג|שירות/i)
        );

        // Update UI with found fields
        document.getElementById('invoiceNumber').textContent = 
            invoiceNumber || 'Not found in PDF';
        document.getElementById('invoiceDate').textContent = 
            dateField || 'Not found in PDF';
        document.getElementById('treatmentReason').textContent = 
            reasonField || 'Not found in PDF';
    });
// Initialize PDF.js
    pdfjsLib.GlobalWorkerOptions.workerSrc = 'https://cdnjs.cloudflare.com/ajax/libs/pdf.js/2.12.313/pdf.worker.min.js';

    // Handle PDF preview
    previewPdfBtn.addEventListener('click', async () => {
        if (!templateUpload.files.length) {
            alert('Please upload a PDF file first');
            return;
        }

        const file = templateUpload.files[0];
        const pdfViewer = document.getElementById('pdfViewer');
        const fileReader = new FileReader();

        fileReader.onload = async function() {
            const typedArray = new Uint8Array(this.result);
            
            try {
                // Load the PDF document
                const pdf = await pdfjsLib.getDocument(typedArray).promise;
                
                // Get the first page
                const page = await pdf.getPage(1);
                
                // Set the scale and viewport
                const scale = 1.5;
                const viewport = page.getViewport({ scale });
                
                // Create canvas for rendering
                const canvas = document.createElement('canvas');
                const context = canvas.getContext('2d');
                canvas.height = viewport.height;
                canvas.width = viewport.width;
                
                // Clear previous content
                pdfViewer.innerHTML = '';
                pdfViewer.appendChild(canvas);
                pdfViewer.style.height = '600px';
                
                // Render PDF page
                await page.render({
                    canvasContext: context,
                    viewport: viewport
                }).promise;
            } catch (error) {
                console.error('Error rendering PDF:', error);
                alert('Error loading PDF. Please try another file.');
            }
        };
        
        fileReader.readAsArrayBuffer(file);
    });
    // Handle CSV upload
    const csvUpload = document.getElementById('csvUpload');
    csvUpload?.addEventListener('change', function(e) {
        const file = e.target.files[0];
        if (!file) return;
        
        const reader = new FileReader();
        reader.onload = function(e) {
const content = e.target.result;
            const lines = content.split('\n');
            
            if (lines.length === 0) {
                alert('CSV file is empty');
                return;
            }
            
            // Parse CSV
            headers = lines[0].split(',');
            csvData = lines.slice(1).map(line => line.split(','));
            
            // Display headers
            const thead = csvPreview.querySelector('thead');
            thead.innerHTML = '';
            const headerRow = document.createElement('tr');
            
            headers.forEach(header => {
                const th = document.createElement('th');
                th.textContent = header;
                headerRow.appendChild(th);
            });
            
            thead.appendChild(headerRow);
            
            // Display first 5 rows
            const tbody = csvPreview.querySelector('tbody');
            tbody.innerHTML = '';
            
            csvData.slice(0, 5).forEach(row => {
                const tr = document.createElement('tr');
                
                row.forEach(cell => {
                    const td = document.createElement('td');
                    td.textContent = cell;
                    tr.appendChild(td);
                });
                
                tbody.appendChild(tr);
            });
            
            // Populate row selection
            rowSelection.innerHTML = '';
            csvData.forEach((_, index) => {
                const option = document.createElement('option');
                option.value = index;
                option.textContent = `Row ${index + 1}`;
                rowSelection.appendChild(option);
            });
        };
        
        reader.readAsText(file);
    });
    // Generate PDFs locally
    generatePdfBtn.addEventListener('click', async () => {
        if (csvData.length === 0) {
            alert('Please upload and process CSV data first');
            return;
        }
        
        const selectedRows = Array.from(rowSelection.selectedOptions).map(opt => parseInt(opt.value));
        
        if (selectedRows.length === 0) {
            alert('Please select at least one row to process');
            return;
        }
        
        try {
            // Create a zip file with all generated PDFs
            const zip = new JSZip();
            const today = new Date();
            const dateString = `${today.getFullYear()}-${String(today.getMonth() + 1).padStart(2, '0')}-${String(today.getDate()).padStart(2, '0')}`;
            
            // Generate a PDF for each selected row
            for (const rowIndex of selectedRows) {
                const rowData = csvData[rowIndex];
                const fileName = `invoice_${rowIndex + 1}.pdf`;
                
                // Create a simple PDF (in a real app, use a proper PDF generation library)
                const pdfContent = `
                    Invoice Details
                    --------------
                    Invoice Number: ${rowData[0] || 'N/A'}
                    Date: ${rowData[1] || 'N/A'}
                    Treatment: ${rowData[2] || 'N/A'}
                    Amount: ${rowData[3] || 'N/A'}
                `;
                
                zip.file(fileName, pdfContent);
            }
            
            // Generate the zip file
            const zipContent = await zip.generateAsync({type: 'blob'});
            const zipUrl = URL.createObjectURL(zipContent);
            
            // Update download link
            downloadLink.href = zipUrl;
            downloadLink.textContent = selectedRows.length > 1 ? 
                `Download ${selectedRows.length} PDFs (ZIP)` : 
                `Download PDF`;
            downloadLink.setAttribute('download', `invoices_${dateString}.zip`);
            downloadSection.classList.remove('d-none');
            
        } catch (error) {
            console.error('Error generating PDFs:', error);
            alert('Failed to generate PDFs');
        }
    });
});