{ coreutils, fetchurl, db, openssl, pcre, perl, pkgconfig, stdenv }:

stdenv.mkDerivation rec {
  name = "exim-4.87";

  src = fetchurl {
    url = "http://mirror.switch.ch/ftp/mirror/exim/exim/exim4/${name}.tar.bz2";
    sha256 = "1jbxn13shq90kpn0s73qpjnx5xm8jrpwhcwwgqw5s6sdzw6iwsbl";
  };

  buildInputs = [ coreutils db openssl pcre perl pkgconfig ];

  preBuild = ''
    sed '
      s:^\(BIN_DIRECTORY\)=.*:\1='"$out"'/bin:
      s:^\(CONFIGURE_FILE\)=.*:\1=/etc/exim.conf:
      s:^\(EXIM_USER\)=.*:\1=ref\:nobody:
      s:^\(SPOOL_DIRECTORY\)=.*:\1=/exim-homeless-shelter:
      s:^# \(SUPPORT_MAILDIR\)=.*:\1=yes:
      s:^EXIM_MONITOR=.*$:# &:
      s:^\(FIXED_NEVER_USERS\)=root$:\1=0:
      s:^# \(WITH_CONTENT_SCAN\)=.*:\1=yes:
      s:^# \(AUTH_PLAINTEXT\)=.*:\1=yes:
      s:^# \(SUPPORT_TLS\)=.*:\1=yes:
      s:^# \(USE_OPENSSL_PC=openssl\)$:\1:
      s:^# \(LOG_FILE_PATH=syslog\)$:\1:
      s:^# \(HAVE_IPV6=yes\)$:\1:
      s:^# \(CHOWN_COMMAND\)=.*:\1=${coreutils}/bin/chown:
      s:^# \(CHGRP_COMMAND\)=.*:\1=${coreutils}/bin/chgrp:
      s:^# \(CHMOD_COMMAND\)=.*:\1=${coreutils}/bin/chmod:
      s:^# \(MV_COMMAND\)=.*:\1=${coreutils}/bin/mv:
      s:^# \(RM_COMMAND\)=.*:\1=${coreutils}/bin/rm:
      s:^# \(TOUCH_COMMAND\)=.*:\1=${coreutils}/bin/touch:
      s:^# \(PERL_COMMAND\)=.*:\1=${perl}/bin/perl:
      #/^\s*#.*/d
      #/^\s*$/d
    ' < src/EDITME > Local/Makefile
  '';

  installPhase = ''
    mkdir -p $out/bin $out/share/man/man8
    cp doc/exim.8 $out/share/man/man8

    ( cd build-Linux-*
      cp exicyclog exim_checkaccess exim_dumpdb exim_lock exim_tidydb \
        exipick exiqsumm exigrep exim_dbmbuild exim exim_fixdb eximstats \
        exinext exiqgrep exiwhat \
        $out/bin )

    ( cd $out/bin
      for i in mailq newaliases rmail rsmtp runq sendmail; do
        ln -s exim $i
      done )
  '';

  meta = {
    homepage = http://exim.org/;
    description = "A mail transfer agent (MTA)";
    license = stdenv.lib.licenses.gpl3;
    platforms = stdenv.lib.platforms.linux;
    maintainers = [ stdenv.lib.maintainers.tv ];
  };
}