index.js

(function() {
  // Helper: Get query parameters from THIS script’s src URL.
  function getScriptQueryParam(param) {
    var params = new URLSearchParams("");
    if (document.currentScript && document.currentScript.src.indexOf('?') !== -1) {
      var queryString = document.currentScript.src.split('?')[1];
      params = new URLSearchParams(queryString);
    } else {
      params = new URLSearchParams(window.location.search);
    }
    return params.get(param);
  }

  // Read required URLs and optional limits from the query parameters.
  var gifUrl = getScriptQueryParam("gif_url");
  var plyUrl = getScriptQueryParam("ply_url");
  // Optional parameters for zoom and angle limits:
  var minZoom = parseFloat(getScriptQueryParam("minZoom")) || 1.5;
  var maxZoom = parseFloat(getScriptQueryParam("maxZoom")) || 5;
  var minAngle = parseFloat(getScriptQueryParam("minAngle")) || 0;
  var maxAngle = parseFloat(getScriptQueryParam("maxAngle")) || 90;

  // Detect if the device is iOS.
  var isIOS = /iPad|iPhone|iPod/.test(navigator.userAgent) && !window.MSStream;

  // Inject CSS styles into the document head.
  var styleEl = document.createElement('style');
  styleEl.textContent = `
    /* Widget container styling */
    #ply-widget-container {
      position: relative;
      width: 100%;
      height: 0;
      padding-bottom: 100%;
    }
    /* When in fake fullscreen mode (iOS fallback) */
    #ply-widget-container.fake-fullscreen {
      position: fixed !important;
      top: 0 !important;
      left: 0 !important;
      width: 100vw !important;
      height: 100vh !important;
      padding-bottom: 0 !important;
      z-index: 9999 !important;
    }
    /* GIF Preview styling */
    #gif-preview-container {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      border: 1px solid #474558;
      border-radius: 10px;
      overflow: hidden;
      cursor: pointer;
    }
    #gif-preview-container img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    /* Viewer Container styling */
    #viewer-container {
      display: none;
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: #FEFEFD;
      border: 1px solid #474558;
      border-radius: 10px;
    }
    /* Canvas fills the viewer container */
    #canvas {
      width: 100%;
      height: 100%;
      display: block;
    }
    /* Progress dialog styling (as a centered div) */
    #progress-dialog {
      position: absolute;
      top: 50%;
      left: 50%;
      transform: translate(-50%, -50%);
      border: none;
      background: rgba(255,255,255,0.9);
      padding: 20px;
      border-radius: 5px;
      z-index: 1000;
      display: none;
    }
    /* Menu (instructions) content styling */
    #menu-content {
      display: none;
      position: absolute;
      top: 72px;
      right: 15px;
      background: #FFFEF4;
      border: 1px solid #474558;
      border-radius: 5px;
      padding: 10px;
      font-size: 15px;
      line-height: 1.4;
      color: #474558;
    }
    /* Button styling */
    .widget-button {
      position: absolute;
      width: 45px;
      height: 45px;
      background-color: #FFFEF4;
      border: 1px solid #474558;
      border-radius: 50%;
      cursor: pointer;
      font-size: 14px;
      color: #474558;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    /* Positions: Close at top-left, fullscreen at top-right, help (instructions) below fullscreen */
    #close-btn {
      top: 17px;
      left: 15px;
    }
    #fullscreen-toggle {
      top: 17px;
      right: 15px;
    }
    #help-toggle {
      top: 72px;
      right: 15px;
    }
  `;
  document.head.appendChild(styleEl);

  // Create the widget container and set its inner HTML.
  var widgetContainer = document.createElement('div');
  widgetContainer.id = 'ply-widget-container';
  widgetContainer.innerHTML = `
    <!-- GIF Preview Container -->
    <div id="gif-preview-container">
      <img id="preview-image" alt="Preview" crossorigin="anonymous">
    </div>
    <!-- Viewer Container -->
    <div id="viewer-container">
      <canvas id="canvas"></canvas>
      <div id="progress-dialog">
        <progress id="progress-indicator" max="100" value="0"></progress>
      </div>
      <button id="close-btn" class="widget-button">X</button>
      <button id="fullscreen-toggle" class="widget-button">⇱</button>
      <button id="help-toggle" class="widget-button">?</button>
      <div id="menu-content">
        - Rotate with right click<br>
        - Zoom in/out with middle click<br>
        - Translate with left click
      </div>
    </div>
  `;
  // Append widgetContainer to the current script's parent so it appears in place.
  document.currentScript.parentNode.appendChild(widgetContainer);

  // Grab element references.
  var gifPreview = document.getElementById('gif-preview-container');
  var viewerContainer = document.getElementById('viewer-container');
  var previewImage = document.getElementById('preview-image');
  var closeBtn = document.getElementById('close-btn');
  var fullscreenToggle = document.getElementById('fullscreen-toggle');
  var helpToggle = document.getElementById('help-toggle');
  var menuContent = document.getElementById('menu-content');
  var canvas = document.getElementById('canvas');
  var progressDialog = document.getElementById('progress-dialog');
  var progressIndicator = document.getElementById('progress-indicator');

  // Set the preview image if provided.
  if (gifUrl) {
    previewImage.src = gifUrl;
  }

  // --- Button Event Handlers ---

  // When the preview image is clicked, hide it, show the viewer, and initialize the 3D viewer.
  gifPreview.addEventListener('click', function() {
    gifPreview.style.display = 'none';
    viewerContainer.style.display = 'block';
    initializeViewer();
  });

  // Close button: hide the viewer and show the preview.
  closeBtn.addEventListener('click', function() {
    // Exit fullscreen if active.
    if (document.fullscreenElement === widgetContainer) {
      if (document.exitFullscreen) {
        document.exitFullscreen();
      }
    }
    // Remove fake-fullscreen class (for iOS) if present.
    widgetContainer.classList.remove('fake-fullscreen');
    viewerContainer.style.display = 'none';
    gifPreview.style.display = 'block';
  });

  // Fullscreen toggle: use native Fullscreen API if available; otherwise, for iOS, toggle a CSS-based fullscreen.
  fullscreenToggle.addEventListener('click', function() {
    if (isIOS) {
      // Toggle fake fullscreen via CSS on iOS.
      if (!widgetContainer.classList.contains('fake-fullscreen')) {
        widgetContainer.classList.add('fake-fullscreen');
      } else {
        widgetContainer.classList.remove('fake-fullscreen');
      }
      // Update icon based on state.
      fullscreenToggle.textContent = widgetContainer.classList.contains('fake-fullscreen') ? '⇲' : '⇱';
    } else {
      // Non-iOS: use standard Fullscreen API.
      if (!document.fullscreenElement) {
        if (widgetContainer.requestFullscreen) {
          widgetContainer.requestFullscreen();
        } else if (widgetContainer.webkitRequestFullscreen) {
          widgetContainer.webkitRequestFullscreen();
        } else if (widgetContainer.mozRequestFullScreen) {
          widgetContainer.mozRequestFullScreen();
        } else if (widgetContainer.msRequestFullscreen) {
          widgetContainer.msRequestFullscreen();
        }
      } else {
        if (document.exitFullscreen) {
          document.exitFullscreen();
        }
      }
    }
  });

  // Update the fullscreen button icon on fullscreen change (for non-iOS browsers).
  document.addEventListener('fullscreenchange', function() {
    if (document.fullscreenElement === widgetContainer) {
      fullscreenToggle.textContent = '⇲';
    } else {
      fullscreenToggle.textContent = '⇱';
    }
  });

  // Help (instructions) toggle: show/hide the instructions.
  helpToggle.addEventListener('click', function(e) {
    e.stopPropagation();
    menuContent.style.display = (menuContent.style.display === 'block') ? 'none' : 'block';
  });

  // --- Initialize the 3D PLY Viewer ---
  async function initializeViewer() {
    // Dynamically import the gsplat library.
    const SPLAT = await import("https://cdn.jsdelivr.net/npm/gsplat@latest");

    // Display the progress dialog by setting its display style to 'block'
    progressDialog.style.display = 'block';

    // Create renderer, scene, camera, and controls.
    const renderer = new SPLAT.WebGLRenderer(canvas);
    const scene = new SPLAT.Scene();
    const camera = new SPLAT.Camera();
    const controls = new SPLAT.OrbitControls(camera, canvas);

    canvas.style.background = "#FEFEFD";
    controls.maxZoom = maxZoom;
    controls.minZoom = minZoom;
    controls.minAngle = minAngle;
    controls.maxAngle = maxAngle;

    controls.update();

    // Load the PLY model from the provided URL.
    try {
      await SPLAT.PLYLoader.LoadAsync(
        plyUrl,
        scene,
        (progress) => {
          progressIndicator.value = progress * 100;
        }
      );
      // Hide the progress dialog once the model is loaded.
      progressDialog.style.display = 'none';
    } catch (error) {
      console.error("Error loading PLY file:", error);
      progressDialog.innerHTML = `<p style="color: red">Error loading model: ${error.message}</p>`;
    }

    // Render loop and resize handling.
    const handleResize = () => {
      renderer.setSize(canvas.clientWidth, canvas.clientHeight);
    };

    const frame = () => {
      controls.update();
      renderer.render(scene, camera);
      requestAnimationFrame(frame);
    };

    handleResize();
    window.addEventListener("resize", handleResize);
    requestAnimationFrame(frame);
  }
})();