contact creation via account

Trigger accCreation on Contact (After Insert){
  switch on Trigger.operationType{
    when BEFORE_INSERT{
      accCreationHelper.createContact(Trigger.new);
    }
  }
}

Public with sharing accCreationHelper{
  public static void createContact(List<Account> accList){
  if(accList != null){
  List<Contact> conUpdate = new List<contact>();
  for(Account a : accList){
  List<contact> conList = new List<contact>();
    for (Integer i = 0 ; i == accList.size() ; i++){
      contact con = new contact();
      con.Id = a.Id;
      con.name = a.name+'i';
      conUpdate.add(con);

    }
  }
  Insert conUpdate;
  }
  }
}