#! /bin/sh

set -e
if [ $# -ne 3 ]; then
  echo >&2 "usage: $0 install|rm GLOB DIR"
  exit 1
fi

mode=$1 glob=$2 dir=$3
case $mode in
  rm)
    printf "Uninstalling aclocal fragments... "
    awk -v dir="$dir" '
      /\*@-([a-zA-Z0-9][-a-zA-Z0-9_]*)-@\*/ {
        out = $0;
        sub(/^.*\*@-/, "", out);
        sub(/-@\*.*$/, "", out);
        system(sprintf("rm %s/%s.m4", dir, out));
      }' <"$glob"
    echo "done."
    ;;
  install)
    printf "Installing aclocal fragments... "
    awk -v dir="$dir" '
      BEGIN { out = ""; delete files; notice = ""}
      /\*@--NOTICE--@\*/ {
        if (out != "") close(out);
        out = "NOTICE";
        notice = $0 "\n";
        next;
      }
      /\*@-([a-zA-Z0-9][-a-zA-Z0-9_]*)-@\*/ {
        if (out != "") close(out);
        out = $0;
        sub(/^.*\*@-/, "", out);
        sub(/-@\*.*$/, "", out);
        files[out] = 1;
        out = sprintf("%s/%s.new", dir, out);
        printf "%s", notice >(out);
      }
      /\*@--[-a-zA-Z0-9_]*-@\*/ { next; }
      {
        if (out == "NOTICE")
          notice = notice $0 "\n";
        else
          if (out != "") print $0 >(out);
      }
      END {
        for (f in files)
          system(sprintf("mv %s/%s.new %s/%s.m4", dir, f, dir, f));
      }' <"$glob"
      echo "done."
    ;;
  *) echo >&2 "bad mode argument"; exit 1;;
esac