Google Apps Script - Drive management

app.js

const parentFolderId = "ID"; // The ID of the main parent folder where files are initially dropped
const parentFolder = DriveApp.getFolderById(parentFolderId);
const parentName = parentFolder.getName()
const files = parentFolder.getFiles();

function moveFiles() {

  while (files.hasNext()) {
    const file = files.next();
    const fileName = file.getName();
    const customerNumber = extractFileNumber(fileName);

    if (customerNumber) {
      const customerFolder = getCustomerFolder(customerNumber, parentFolder);
      const destinationFolder = getDestinationFolder(fileName, customerFolder);

      if (destinationFolder) {
        file.moveTo(destinationFolder);
        Logger.log(`Moved file ${fileName} to folder: ${destinationFolder.getName()}`);
      } else {
        Logger.log(`No destination folder found for file: ${fileName}`);
      }
    } else {
      Logger.log(`File number not found in file name: ${fileName}`);
    }
  }
}

function extractFileNumber(fileName) {
  const match = fileName.match(/_(\d+)$/); // Adjust the regex according to your file naming convention
  return match ? match[1] : null;
}

function getCustomerFolder(customerNumber, parentFolder) {
  const folders = parentFolder.getFoldersByName(`Customer_${customerNumber}`);
  return folders.hasNext() ? folders.next() : null;
}

function getDestinationFolder(fileName, customerFolder) {
  if (!customerFolder) return null;

  // Logic to determine the destination subfolder based on the file name
  // For example, if file name contains "invoice" it goes to "Invoices" subfolder
  if (fileName.toLowerCase().includes("invoice")) {
    return getOrCreateFolder(customerFolder, "Invoice");
  } else if (fileName.toLowerCase().includes("correspondence")) {
    return getOrCreateFolder(customerFolder, "Correspondence");
  } else if (fileName.toLowerCase().includes("contract")) {
    return getOrCreateFolder(customerFolder, "Contract");
  } else {
    return getOrCreateFolder(customerFolder, "Other");
  }
}

function getOrCreateFolder(topFolder, folderName) {
  const folders = topFolder.getFoldersByName(folderName);
  return folders.hasNext() ? folders.next() : topFolder.createFolder(folderName);
}

function moveFilesToParentFolder() {
  const levelOnefolders = parentFolder.getFolders();

  if (levelOnefolders.hasNext()) {
    // Iterate through all customer folders
    while (levelOnefolders.hasNext()) {
      const levelOneFolder = levelOnefolders.next();
      moveFilesFromSubfoldersToParent(levelOneFolder, parentFolder);
    }
  } else {
    Logger.log("No Folders in Parent Folder");
  }
}

function moveFilesFromSubfoldersToParent(folder, rootFolder) {
  const subFolders = folder.getFolders();
  const files = folder.getFiles();

  fileCheckAndMove(files, rootFolder);

  // Iterate through all subfolders - invoice, contracts, etc
  while (subFolders.hasNext()) {
    const subFolder = subFolders.next();
    const subFiles = subFolder.getFiles();
    fileCheckAndMove(subFiles, rootFolder);
    
    if (hasSubFolders(subFolder)) {
      fileCheckAndMove(subFolder, rootFolder)
    }
  }
}

function hasSubFolders(folder) {
  return folder.getFolders().hasNext();
}

function fileCheckAndMove(files, rootFolder) {
  if (!files.hasNext) return null

  while (files.hasNext()) {
    const file = files.next();
    file.moveTo(rootFolder);
    Logger.log(`File ${file.getName()} moved from ${file.getParents()[0]} to ${rootFolder.getName()}`);
  }
}