/* VERP address extractor.
   Copyright (C) 2008-2020 Sergey Poznyakoff

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>. */

module 'verp'.
#pragma regex push +extended

func verp_extract_user(string email, string domain)
  returns string
do
  if email matches "(.*)=%domain@.*"
    string s \1
    if s matches '.*\+([^\+]+)$' and validuser(\1)
      return \1
    elif s matches 'sentto-[0-9]{7}-[0-9]{4}-[0-9]{10}-(.*)$' and validuser(\1)
      return \1
    fi
  fi
  return ""
done

#pragma regex pop