Function processFiles

public/js/upload.js:1048–1163

(filesInput)

   - Used for XHR fallback + grouping in the upload UI.
------------------------------------------------------ */
function processFiles(filesInput) {
  const fileInfoContainer = document.getElementById("fileInfoContainer");
  const files = Array.from(filesInput);

  if (fileInfoContainer) {
    if (files.length > 0) {
      if (files.length === 1) {
        fileInfoContainer.innerHTML = `
          <div id="filePreviewContainer" class="file-preview-container" style="display:inline-block;">
            <span class="material-icons file-icon">insert_drive_file</span>
          </div>
          <span id="fileNameDisplay" class="file-name-display">${escapeHTML(files[0].name || files[0].fileName || "Unnamed File")}</span>
        `;
      } else {
        fileInfoContainer.innerHTML = `
          <div id="filePreviewContainer" class="file-preview-container" style="display:inline-block;">
            <span class="material-icons file-icon">insert_drive_file</span>
          </div>
          <span id="fileCountDisplay" class="file-name-display">${files.length} files selected</span>
        `;
      }
      const previewContainer = document.getElementById("filePreviewContainer");
      if (previewContainer) {
        previewContainer.innerHTML = "";
        displayFilePreview(files[0].file || files[0], previewContainer);
      }
    } else {
      fileInfoContainer.innerHTML = `<span id="fileInfoDefault">No files selected</span>`;
    }
  }

  files.forEach((file, index) => {
    file.uploadIndex = index;
  });

  const progressContainer = document.getElementById("uploadProgressContainer");
  progressContainer.innerHTML = "";

  if (files.length > 0) {
    const maxDisplay = 10;
    const list = document.createElement("ul");
    list.classList.add("upload-progress-list");

    // Check for relative paths (for folder uploads).
    const hasRelativePaths = files.some(file => {
      const rel = file.webkitRelativePath || file.customRelativePath || "";
      return rel.trim() !== "";
    });

    if (hasRelativePaths) {
      // Group files by folder.
      const fileGroups = {};
      files.forEach(file => {
        let folderName = "Root";
        const relativePath = file.webkitRelativePath || file.customRelativePath || "";
        if (relativePath.trim() !== "") {
          const parts = relativePath.split("/");
          if (parts.length > 1) {