Copy google spreadsheet with all protected ranges permissions

Copy.gs

function Main() {
  var template = DriveApp.getFileById('YOUR_SPREADSHEET_ID');              //template spreadsheet
  var destination = DriveApp.getFolderById('COPY_DESTINATION_FOLDER_ID');  //the directory to copy the file into
  var curDate = Utilities.formatDate(new Date(), Session.getScriptTimeZone(), "yyyy-MM-dd");
  var copyName = template.getName() + ' copy ' + curDate;                  //the filename that should be applied to the new copy (e.g. "My spreadsheet copy 2019-08-24")

  copyTemplate(template, copyName, destination);
}

/**
 * Copy google spreadsheet with all protected ranges permissions
 *
 * @param {File} template - Template spreadsheet
 * @param {string} [copyName] - The filename that should be applied to the new copy (Optional)
 * @param {Folder} [destination] - The directory to copy the file into (Optional)
 * @param {boolean} [allowDuplicates] - Allow copying if a file with a given name already exists (Optional)
 * @throws Will throw an error if an error occurs ¯\_(ツ)_/¯
 * @example
 *     //creates a copy of the template with the same name, inside the root directory, ignore the duplicates
 *     var myTemplate = DriveApp.getFileById('MY_TEMPLATE_ID');
 *     copyTemplate(myTemplate);
 * @example
 *     //creates a copy of the template with the same name, inside the defined directory, if no duplicates exist
 *     var myTemplate = DriveApp.getFileById('MY_TEMPLATE_ID');
 *     var copyDestination = DriveApp.getFolderById('DESTINATION_DIRECTORY_ID');
 *     copyTemplate(myTemplate, null, copyDestination, false);
 */
function copyTemplate(template, copyName, destination, allowDuplicates) {
  var newSheet, templateSheet, fileIterator;

  //set defaults
  copyName = copyName || template.getName();
  destination = destination || DriveApp.getRootFolder();
  allowDuplicates = allowDuplicates === false ? false : true;
  
  //if duplicates are disallowed and a file with the given name already exists, stop execution
  if(!allowDuplicates) {
    fileIterator = destination.getFilesByName(copyName);
    
    while (fileIterator.hasNext()) {
      if(fileIterator.next().getMimeType() == MimeType.GOOGLE_SHEETS) {
        throw new Error("File already exists");
      }
    }
  }
  
  templateSheet = SpreadsheetApp.open(template);
  newSheet = SpreadsheetApp.open(template.makeCopy(copyName, destination));
  
  //copy protections from the template to the new spreadsheet
  copyProtections(templateSheet, newSheet);
}

/**
 * Copies protections from the origin to the target
 *
 * @param {Spreadsheet} origin - Origin spreadsheet
 * @param {Spreadsheet} target - Target spreadsheet
 */
function copyProtections(origin, target) {
  var sheets = origin.getSheets();
  
  for(var i = 0; i < sheets.length; i++) {
    var newSheet = target.getSheetByName(sheets[i].getName());
    var sheetProtection = sheets[i].getProtections(SpreadsheetApp.ProtectionType.SHEET)[0];
    var newSheetProtection = newSheet.getProtections(SpreadsheetApp.ProtectionType.SHEET)[0];
    var rangeProtections = sheets[i].getProtections(SpreadsheetApp.ProtectionType.RANGE);
    var newRangeProtections = newSheet.getProtections(SpreadsheetApp.ProtectionType.RANGE);
    
    //Recreate sheet protection from scratch
    if(sheetProtection) {
      var unprotected = sheetProtection.getUnprotectedRanges();
      var newUnprotected = [];
      for (var j = 0; j < unprotected.length; j++) {
        newUnprotected.push(newSheet.getRange(unprotected[j].getA1Notation()));
      }
      cloneProperties(sheetProtection, newSheetProtection);
      newSheetProtection.setUnprotectedRanges(newUnprotected);
    }
    
    //Remove range protections in the new sheet
    for(var j = 0; j < newRangeProtections.length; j++) {
      newRangeProtections[j].remove();
    }
    
    //Recereate range protections from scratch
    for (var j = 0; j < rangeProtections.length; j++) {
      var protection = rangeProtections[j];
      var newProtection;
      
      if(protection.getRangeName()) {
        //if protection is set to the named range
        newProtection = target.getRangeByName(protection.getRangeName()).protect();
        newProtection.setRangeName(protection.getRangeName());
      } else {
        newProtection = newSheet.getRange(protection.getRange().getA1Notation()).protect();
      }
      cloneProperties(protection, newProtection);
    }//end of ranges
  }//end of sheets
}

/**
 * Copies protection object basic properties
 *
 * @param {Protection} origin - Protection object of the source
 * @param {Protection} target - Protection object of the target
 */
function cloneProperties(origin, target) {
  target.setDescription(origin.getDescription());
  target.setWarningOnly(origin.isWarningOnly());

  if (!origin.isWarningOnly()) {
    var editors = origin.getEditors();
    var oldEditors = target.getEditors();
 
    for(var i = 0; i < oldEditors.length; i++) {
      target.removeEditor(oldEditors[i]);
    }
    for(var i = 0; i < editors.length; i++) {
      target.addEditor(editors[i]);
    }
    if (origin.canDomainEdit()) {
      target.setDomainEdit(true);
    }
  }
}