index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Images to PDF</title>
    <style>
        body {
            font-family: Arial, sans-serif;
            margin: 50px;
            text-align: center;
            touch-action: none; /* Prevent default touch behaviors like scrolling */
        }
        #imageContainer {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 10px;
            margin: 20px 0;
            padding: 10px;
            border: 1px solid #ccc;
        }
        .imageWrapper {
            max-width: 200px;
            cursor: move; /* For desktop */
            position: relative;
            user-select: none; /* Prevent text selection during drag/touch */
        }
        .imageWrapper img {
            max-width: 100%;
            height: auto;
            border: 1px solid #ddd;
            border-radius: 5px;
        }
        .imageWrapper.dragging {
            opacity: 0.5; /* Visual feedback during drag/touch */
        }
        .imageWrapper.over {
            border: 2px dashed #4CAF50; /* Visual feedback for drop target */
        }
        button {
            padding: 10px 20px;
            font-size: 16px;
            cursor: pointer;
            background-color: #4CAF50;
            color: white;
            border: none;
            border-radius: 5px;
        }
        button:hover {
            background-color: #45a049;
        }
    </style>
</head>
<body>
    <h1>Images to PDF Converter</h1>
    <input type="file" id="imageInput" accept="image/*" multiple>
    <p>Drag and drop (desktop) or tap and move (mobile) images to reorder them for the PDF.</p>
    <div id="imageContainer"></div>
    <button onclick="generatePDF()">Download as PDF</button>

    <script src="https://cdnjs.cloudflare.com/ajax/libs/jspdf/2.5.1/jspdf.umd.min.js"></script>
    <script>
        const { jsPDF } = window.jspdf;
        const imageInput = document.getElementById('imageInput');
        const imageContainer = document.getElementById('imageContainer');
        let images = [];

        // Handle image uploads
        imageInput.addEventListener('change', (event) => {
            images = [];
            imageContainer.innerHTML = '';
            const files = Array.from(event.target.files);

            files.forEach((file) => {
                const reader = new FileReader();
                reader.onload = (e) => {
                    const img = new Image();
                    img.src = e.target.result;
                    img.onload = () => {
                        images.push({ src: e.target.result, width: img.width, height: img.height });
                        renderImages();
                    };
                };
                reader.readAsDataURL(file);
            });
        });

        // Render images with drag-and-drop and touch functionality
        function renderImages() {
            imageContainer.innerHTML = '';
            images.forEach((image, index) => {
                const wrapper = document.createElement('div');
                wrapper.className = 'imageWrapper';
                wrapper.draggable = true;
                wrapper.dataset.index = index;

                const img = new Image();
                img.src = image.src;
                wrapper.appendChild(img);

                // Desktop drag-and-drop
                wrapper.addEventListener('dragstart', (e) => {
                    wrapper.classList.add('dragging');
                    e.dataTransfer.setData('text/plain', index);
                });

                wrapper.addEventListener('dragend', () => {
                    wrapper.classList.remove('dragging');
                    clearOverStyles();
                });

                wrapper.addEventListener('dragover', (e) => {
                    e.preventDefault();
                    wrapper.classList.add('over');
                });

                wrapper.addEventListener('dragleave', () => {
                    wrapper.classList.remove('over');
                });

                wrapper.addEventListener('drop', (e) => {
                    e.preventDefault();
                    const draggedIndex = parseInt(e.dataTransfer.getData('text/plain'));
                    const dropIndex = parseInt(wrapper.dataset.index);
                    reorderImages(draggedIndex, dropIndex);
                    renderImages();
                });

                // Touch events for mobile
                wrapper.addEventListener('touchstart', (e) => {
                    e.preventDefault();
                    wrapper.classList.add('dragging');
                    startTouchReorder(e, wrapper, index);
                });

                wrapper.addEventListener('touchmove', (e) => {
                    e.preventDefault();
                    handleTouchMove(e, wrapper);
                });

                wrapper.addEventListener('touchend', (e) => {
                    e.preventDefault();
                    wrapper.classList.remove('dragging');
                    endTouchReorder(wrapper, index);
                    clearOverStyles();
                });

                imageContainer.appendChild(wrapper);
            });
        }

        // Touch reordering logic
        let touchStartY = 0;
        let targetIndex = null;

        function startTouchReorder(event, wrapper, index) {
            const touch = event.touches[0];
            touchStartY = touch.clientY;
            targetIndex = index;
        }

        function handleTouchMove(event, wrapper) {
            const touch = event.touches[0];
            const touchY = touch.clientY;

            // Find the element under the touch point
            const elements = document.elementsFromPoint(touch.clientX, touchY);
            const targetWrapper = elements.find(el => el.classList.contains('imageWrapper') && el !== wrapper);

            // Clear previous 'over' styles
            clearOverStyles();

            if (targetWrapper) {
                targetWrapper.classList.add('over');
            }
        }

        function endTouchReorder(wrapper, startIndex) {
            const overElement = document.querySelector('.imageWrapper.over');
            if (overElement) {
                const dropIndex = parseInt(overElement.dataset.index);
                reorderImages(startIndex, dropIndex);
                renderImages();
            }
        }

        function clearOverStyles() {
            document.querySelectorAll('.imageWrapper.over').forEach(el => el.classList.remove('over'));
        }

        function reorderImages(draggedIndex, dropIndex) {
            if (draggedIndex !== dropIndex) {
                const [draggedImage] = images.splice(draggedIndex, 1);
                images.splice(dropIndex, 0, draggedImage);
            }
        }

        // Generate PDF from images
        function generatePDF() {
            if (images.length === 0) {
                alert('Please upload at least one image.');
                return;
            }

            const doc = new jsPDF();
            const pageWidth = doc.internal.pageSize.getWidth();
            const pageHeight = doc.internal.pageSize.getHeight();
            const margin = 10;
            const maxImgWidth = pageWidth - 2 * margin;
            const maxImgHeight = pageHeight - 2 * margin;

            images.forEach((image, index) => {
                if (index > 0) {
                    doc.addPage();
                }

                // Calculate scaling to fit image within page
                let imgWidth = image.width;
                let imgHeight = image.height;
                const ratio = Math.min(maxImgWidth / imgWidth, maxImgHeight / imgHeight);
                imgWidth = imgWidth * ratio;
                imgHeight = imgHeight * ratio;

                // Center the image on the page
                const x = (pageWidth - imgWidth) / 2;
                const y = (pageHeight - imgHeight) / 2;

                doc.addImage(image.src, 'JPEG', x, y, imgWidth, imgHeight);
            });

            doc.save('images.pdf');
        }
    </script>
</body>
</html>