#!/bin/sh

SELF="${0##*/}"

if [ -z "$TMPDIR" ]; then
  TMPDIR=/tmp
elif [ -d "${TMPDIR}/volatile" ]; then
  TMPDIR="${TMPDIR}/volatile"
fi
export TMPDIR
TMPDIR=$(mktemp -dp "$TMPDIR" mutt.XXXXXXXXXX)
cleanup() { cd / && rm -rf "$TMPDIR"; }
trap cleanup 1 2 3 4 5 6 7 8 10 11 12 13 14 15

cd "$TMPDIR"

notify() {
  if [ -x "$(command -v awesome-client)" ]; then
    awesome-client <<-_eof
	local naughty = require("naughty")
	naughty.notify({ preset = naughty.config.presets.low,
		title  = "$3",
		text   = [[stdout:
		$(sed -e 's,\",\\\",g' "$1")
		stderr:
		$(sed -e 's,\",\\\",g' "$2")]]
		})
	_eof
  fi
}

guess_extension() {
  python -c "import mimetypes; print(mimetypes.guess_extension('$1'))"
}

launch_viewer() {
  run-mailcap --action=view "$1":"$2" > output.stdout 2> output.stderr
}

MIMETYPE="$1"
TEMPFILE=$(tempfile -d . -p mutt -s $(guess_extension "$MIMETYPE"))

case "$SELF" in
  (bgrun)
    # make a copy of the file, then launch a shell process in the background
    # to divert to run-mailcap, after which the temporary directory gets
    # cleaned up.
    cat > "$TEMPFILE"
    (
    launch_viewer "$MIMETYPE" "$TEMPFILE"
      if [ -s "$TMPDIR/output.stdout" ] || [ -s "$TMPDIR/output.stderr" ]; then
        notify $TMPDIR/output.stdout $TMPDIR/output.stderr \
          "Output from mutt/$SELF on $BASENAME"
      fi
      cleanup
    ) &
    trap - 1 2 3 4 5 6 7 8 10 11 12 13 14 15
    ;;
  (bgrun-fifo)
    # hack to stay around until the viewer has read the file: make a fifo and
    # wait for the cat process to finish writing to it, which means that it
    # must have been consumed on the other end.
    cat > "$TEMPFILE"
    FIFO="${TEMPFILE%/*}/fifo-${TEMPFILE##*/}"
    mkfifo "$FIFO"
    cat "$TEMPFILE" > "$FIFO" &
    # For some reason, we do have to write a tempfile and cannot seem to
    # redirect stdin directly to the fifo, i.e. this does not work instead of
    # the previous three lines:
    ## cat > "$FIFO" &
    launch_viewer "$MIMETYPE" "${FIFO}"
    wait
    cleanup
    ;;
esac