document.addEventListener('DOMContentLoaded', function() {
    // Initialize empty results array
    const scanResults = [];
    
    // Camera and storage access variables
    let cameraStream = null;
    let isCameraActive = false;
    const cameraVideo = document.getElementById('cameraStream');
    const captureCanvas = document.getElementById('captureCanvas');
    const placeholderImage = document.getElementById('placeholderImage');
    const uploadButton = document.getElementById('uploadButton');
    const captureButton = document.getElementById('captureButton');
    const textPreview = document.querySelector('.text-preview');
    
    // Tab switching functionality
    const tabButtons = document.querySelectorAll('.tab-button');
    const tabContents = document.querySelectorAll('.tab-content');

    // Initialize tabs - show home tab by default
    document.getElementById('home').classList.add('active');
    
    tabButtons.forEach(button => {
        button.addEventListener('click', function(e) {
            e.preventDefault();
            const tabId = this.getAttribute('data-tab');

            // Remove active class from all tabs and buttons
            tabButtons.forEach(btn => btn.classList.remove('active'));
            tabContents.forEach(content => content.classList.remove('active'));

            // Add active class to clicked tab and button
            this.classList.add('active');
            document.getElementById(tabId).classList.add('active');
            
            // Stop camera when leaving home tab
            if (tabId !== 'home') {
                stopCamera();
            }
        });
    });

    // Initialize the first tab as active
    const initialTab = document.querySelector('.tab-button[data-tab="home"]');
    if (initialTab) {
        initialTab.classList.add('active');
    }

    // Request camera permission and initialize camera
    async function initializeCamera() {
        try {
            // Stop any existing camera stream
            stopCamera();
            
            // Try environment camera first, then user camera, then any camera
            const constraints = [
                { video: { facingMode: 'environment' } },
                { video: { facingMode: 'user' } },
                { video: true }
            ];
            
            let stream = null;
            for (const constraint of constraints) {
                try {
                    stream = await navigator.mediaDevices.getUserMedia(constraint);
                    break;
                } catch (err) {
                    console.warn(`Camera constraint failed:`, constraint, err);
                    continue;
                }
            }
            
            if (!stream) {
                throw new Error('No camera available');
            }
            
            cameraStream = stream;
            cameraVideo.srcObject = stream;
            isCameraActive = true;
            
            // Wait for video to load metadata
            await new Promise((resolve) => {
                cameraVideo.onloadedmetadata = resolve;
            });
            
            return true;
        } catch (error) {
            console.error('Error accessing camera:', error);
            alert('Camera access is required for capturing images. Please allow camera permissions and ensure a camera is connected.');
            isCameraActive = false;
            return false;
        }
    }

    // Stop camera stream
    function stopCamera() {
        if (cameraStream) {
            const tracks = cameraStream.getTracks();
            tracks.forEach(track => {
                track.stop();
            });
            cameraStream = null;
        }
        isCameraActive = false;
        cameraVideo.style.display = 'none';
        placeholderImage.style.display = 'block';
    }

    // Capture image from camera
    async function captureImage() {
        // Ensure camera is initialized
        if (!isCameraActive) {
            const initialized = await initializeCamera();
            if (!initialized) {
                alert('Failed to access camera. Please check permissions.');
                return;
            }
        }
        
        try {
            // Show camera stream and hide placeholder
            placeholderImage.style.display = 'none';
            cameraVideo.style.display = 'block';
            
            // Small delay to let camera stabilize
            await new Promise(resolve => setTimeout(resolve, 200));
            
            // Set canvas dimensions to match video
            captureCanvas.width = cameraVideo.videoWidth || 640;
            captureCanvas.height = cameraVideo.videoHeight || 480;
            
            const context = captureCanvas.getContext('2d');
            
            // Draw video frame to canvas
            context.drawImage(cameraVideo, 0, 0, captureCanvas.width, captureCanvas.height);
            
            // Get image data URL
            const imageData = captureCanvas.toDataURL('image/jpeg', 0.8);
            
            // Process the captured image
            processCapturedImage(imageData);
            
            // Stop camera after capture
            stopCamera();
        } catch (error) {
            console.error('Error capturing image:', error);
            alert('Failed to capture image. Please try again.');
            stopCamera();
        }
    }

    // Process captured image and show results
    function processCapturedImage(imageData) {
        // Show image preview
        const imagePreviewContainer = document.querySelector('.image-preview-container');
        const previewImage = document.getElementById('preview-image');
        previewImage.src = imageData;
        imagePreviewContainer.style.display = 'block';
        
        // Store and simulate OCR results with sample data
        const result = {
            type: 'scan',
            content: 'The quick brown fox jumps over the lazy dog\n1234567890',
            confidence: '98.7%',
            timestamp: new Date().toISOString(),
            imageData: imageData
        };
        scanResults.push(result);
        
        // Show results with image preview and processed text
        textPreview.innerHTML = `
            <div class="result-header">
                <div class="result-icon">
                    <i class="fas fa-camera"></i>
                </div>
                <h4>Scan Results</h4>
            </div>
            <div class="result-content">
                <p class="ocr-text">The quick brown fox jumps over the lazy dog</p>
                <p class="ocr-text">1234567890</p>
            </div>
            <div class="result-meta">
                <span class="confidence">Confidence: 98.7%</span>
            </div>
            <p class="timestamp">Processed at ${new Date().toLocaleTimeString()}</p>
        `;
        
        // Add processed text section after results
        const processedTextSection = document.createElement('div');
        processedTextSection.className = 'processed-text-section';
        processedTextSection.innerHTML = `
            <h4>Processed Text</h4>
            <div class="processed-text-content">
The quick brown fox jumps over the lazy dog
1234567890
            </div>
        `;
        
        textPreview.appendChild(processedTextSection);
    }

    // Capture button functionality
    captureButton.addEventListener('click', async function() {
        await captureImage();
    });

    // Upload button functionality
    uploadButton.addEventListener('click', function() {
        // Create file input for upload
        const fileInput = document.createElement('input');
        fileInput.type = 'file';
        fileInput.accept = 'image/*';
        fileInput.style.display = 'none';
        document.body.appendChild(fileInput);
        
        fileInput.addEventListener('change', function(e) {
            const file = e.target.files[0];
            if (file) {
                // Stop camera if active
                stopCamera();
                
                // Show upload processing
                textPreview.innerHTML = `
                    <div class="upload-animation">
                        <div class="progress-bar">
                            <div class="progress"></div>
                        </div>
                        <p><i class="fas fa-cloud-upload-alt fa-pulse"></i> Processing image...</p>
                    </div>
                `;
                
                const reader = new FileReader();
                reader.onload = function(event) {
                    setTimeout(() => {
                        // Show image preview
                        const imagePreviewContainer = document.querySelector('.image-preview-container');
                        const previewImage = document.getElementById('preview-image');
                        previewImage.src = event.target.result;
                        imagePreviewContainer.style.display = 'block';
                        
                        // Store and simulate OCR results with sample data
                        const result = {
                            type: 'document',
                            content: 'Invoice #INV-2023-0456\nClient: Acme Corporation\nTotal: $1,245.00\nDue Date: 12/15/2023',
                            timestamp: new Date().toISOString(),
                            imageData: event.target.result
                        };
                        scanResults.push(result);
                        
                        // Show results with image preview and processed text
                        textPreview.innerHTML = `
                            <div class="result-header">
                                <div class="result-icon">
                                    <i class="fas fa-file-alt"></i>
                                </div>
                                <h4>Document Analysis</h4>
                            </div>
                            <div class="result-content">
                                <p class="ocr-text">Invoice #INV-2023-0456</p>
                                <p class="ocr-text">Client: Acme Corporation</p>
                                <p class="ocr-text">Total: $1,245.00</p>
                                <p class="ocr-text">Due Date: 12/15/2023</p>
                            </div>
                            <p class="timestamp">Processed at ${new Date().toLocaleTimeString()}</p>
                        `;
                        
                        // Add processed text section after results
                        const processedTextSection = document.createElement('div');
                        processedTextSection.className = 'processed-text-section';
                        processedTextSection.innerHTML = `
                            <h4>Processed Text</h4>
                            <div class="processed-text-content">
Invoice #INV-2023-0456
Client: Acme Corporation
Total: $1,245.00
Due Date: 12/15/2023
                            </div>
                        `;
                        
                        textPreview.appendChild(processedTextSection);
                    }, 1500);
                };
                reader.readAsDataURL(file);
            }
        });
        
        fileInput.click();
    });

    // Function to close image preview
    window.closeImagePreview = function() {
        const imagePreviewContainer = document.querySelector('.image-preview-container');
        imagePreviewContainer.style.display = 'none';
    };
});
// Add scanning animation styles
const style = document.createElement('style');
style.textContent = `
    .scanning-animation {
        position: relative;
        height: 100%;
        overflow: hidden;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 15px;
    }
    .scan-line {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 2px;
        background: var(--primary-color);
        animation: scan 1.5s linear infinite;
    }
    @keyframes scan {
        0% { top: 0; opacity: 0; }
        10% { opacity: 1; }
        90% { opacity: 1; }
        100% { top: 100%; opacity: 0; }
    }
    .result-header {
        display: flex;
        align-items: center;
        gap: 10px;
        margin-bottom: 12px;
    }
    .result-icon {
        width: 30px;
        height: 30px;
        background: var(--secondary-color);
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        color: var(--primary-color);
    }
    .result-content {
        margin: 10px 0;
    }
    .result-meta {
        margin-top: 8px;
        font-size: 0.8rem;
        color: var(--light-text);
    }
    .confidence {
        background: rgba(37, 99, 235, 0.1);
        padding: 4px 8px;
        border-radius: 4px;
    }
    .upload-animation {
        position: relative;
        height: 100%;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 15px;
    }
    .progress-bar {
        width: 80%;
        height: 8px;
        background: var(--border-color);
        border-radius: 4px;
        overflow: hidden;
    }
    .progress {
        height: 100%;
        width: 0;
        background: linear-gradient(90deg, var(--primary-color), var(--primary-dark));
        animation: progress 2.5s ease-out forwards;
    }
    @keyframes progress {
        0% { width: 0; }
        100% { width: 100%; }
    }
`;
document.head.appendChild(style);