#! /bin/bash -e

prog=${0##*/}
dev=${DVDRIP_DEVICE-/dev/dvd}
tmp=${DVDRIP_TMPDIR-${HOME?}/tmp/dvdrip}
archive=${DVDRIP_ARCHIVE-jem.distorted.org.uk:/mnt/dvd/archive}
: ${DVD_SECTOR_COPY=dvd-sector-copy}
: ${DVD_ID=dvd-id}
: ${DVDRIP_UPLOAD=dvdrip-upload}
backup=nil ding=nil eject=nil force=nil retry=nil verbose=nil bogus=nil
unset params
usage () {
  cat <<EOF
usage: $prog [-defrv] [-D DEV] [-a ARCH] [-t TMP] TITLE
EOF
}
while getopts "hB:D:a:defrt:v" opt; do
  case $opt in
    h) usage; exit 0 ;;
    B) params=${params+$params,}$OPTARG ;;
    D) dev=$OPTARG ;;
    a) archive=$OPTARG ;;
    d) ding=t ;;
    e) eject=t ;;
    f) force=t ;;
    r) retry=t ;;
    t) tmp=$OPTARG ;;
    v) verbose=t ;;
    *) bogus=t ;;
  esac
done
shift $(( $OPTIND - 1 ))
case $# in 1) title=$1 ;; *) bogus=t ;; esac
case $bogus in t) usage >&2; exit 2 ;; esac
case $verbose in t) set -x ;; esac
case $archive in
  *:*) archhost=${archive%%:*} archpath=${archive#*:} ;;
  *) unset archhost; archpath=$archive ;;
esac

notify () {
  colour=$1 message=$2
  echo "$(tput bold; tput setaf $colour)$message$(tput sgr0; tput op)"
}
fail () { notify 1 "!!! $*"; exit 2; }
warn () { notify 5 "??? $*"; }
info () { notify 6 "--- $*"; }
run_setrc () {
  notify 2 "+++ $*";
  set +e; nice "$@"; rc=$?; set -e
}
run () { run_setrc "$@"; case $rc in 0) ;; *) fail "$1: exit $rc" ;; esac; }

archdo () {
  op=$1; shift
  case ${archhost+t} in
    t)
      qq=
      for a in "$@"; do
	qq="${qq:+$qq }'${a//\'/"'\\''"}'" #" # emacs is confused
      done
      "$op" ssh "$archhost" "$qq"
      ;;
    *)
      "$op" "$@"
      ;;
  esac
}
archrun () { archdo run "$@"; }

tag=${title//\//_}

archdo run_setrc test -f "$archpath/$title.iso"
case $rc,$force in
  0,nil) fail "output file already exists" ;;
  0,t) warn "output file already exists; will overwrite" ;;
esac

mkdir -p "$tmp/$tag"

discid=$("$DVD_ID" -I "$dev")
if [ -f "$tmp/$tag/discid" ]; then
  read oldid <"$tmp/$tag/discid"
  case $force,$oldid in
    t,"$discid" | nil,"$discid")
      ;;
    nil,*)
      fail "discid mismatch: expected \`$oldid' but drive has \`$discid'"
      ;;
    t,*)
      warn "discid mismatch: expected \`$oldid' but drive has \`$discid'; continuing anway"
      ;;
  esac
fi
info "copying \`$discid'"
echo "$discid" >"$tmp/$tag/discid.new"
mv "$tmp/$tag/discid.new" "$tmp/$tag/discid"

if [ -b "$dev" ]; then msz=$(blockdev --getsize64 "$dev")
else msz=nil; fi

echo "$dev" >"$tmp/$tag/device.new"
mv "$tmp/$tag/device.new" "$tmp/$tag/device"

accumulate_badblocks () {
  if [ -f "$tmp/$tag/badblocks.new" ]; then
    if [ ! -f "$tmp/$tag/badblocks" ]; then
      { echo "## bad-blocks region map"; echo; } >"$tmp/$tag/badblocks"
    fi
    sed -n "/^[^#]/p" "$tmp/$tag/badblocks.new" >>"$tmp/$tag/badblocks"
    rm "$tmp/$tag/badblocks.new"
  fi
}

set --
any=nil
for i in "$tmp/$tag/dest.new" "$tmp/$tag/dest" "$tmp/$tag/dest.seen"; do
  if [ -f "$tmp/$tag/dest.new" ]; then any=t; fi
done
case $any in
  nil) printf "%s\n" "$title.iso" >"$tmp/$tag/dest.new" ;;
esac
case $eject in
  t) touch "$tmp/$tag/eject" ;;
  nil) rm -f "$tmp/$tag/eject" ;;
esac
case $ding in
  t) touch "$tmp/$tag/ding" ;;
  nil) rm -f "$tmp/$tag/ding" ;;
esac

accumulate_badblocks
case $retry in
  t)
    if [ -f "$tmp/$tag/badblocks.retry" ]; then
      :
    elif [ -f "$tmp/$tag/badblocks" ]; then
      run mv "$tmp/$tag/badblocks" "$tmp/$tag/badblocks.retry"
    else
      fail "no blocks to retry"
    fi
    set -- "$@" -R"$tmp/$tag/badblocks.retry"
    if [ -f "$tmp/$tag/iso" ]; then
      mv "$tmp/$tag/iso" "$tmp/$tag/iso.new"
    fi
    ;;
esac
if [ ! -f "$tmp/$tag/iso" ]; then
  run "$DVD_SECTOR_COPY" -cs ${params+"-B$params"} \
      -b"$tmp/$tag/badblocks.new" "$@" "$dev" "$tmp/$tag/iso.new"
  run mv "$tmp/$tag/iso.new" "$tmp/$tag/iso"
  accumulate_badblocks
  rm -f "$tmp/$tag/device"
  case $retry in t) rm -f "$tmp/$tag/badblocks.retry" ;; esac
  if [ -f "$tmp/$tag/badblocks" ]; then
    fail "bad sectors found: check \`$tmp/$tag/iso', run again if ok"
  fi
  case $msz in
    nil) ;;
    *)
      newmsz=$(blockdev --getsize64 "$dev")
      case $newmsz in
	$msz) ;;
	*) fail "medium size changed ($msz -> $newmsz): try again" ;;
      esac
      ;;
  esac
fi

rm -f "$tmp/$tag/device"
run mv "$tmp/$tag/dest.new" "$tmp/$tag/dest"
if [ -f "$tmp/$tag/eject" ]; then eject=t; else eject=nil; fi
if [ -f "$tmp/$tag/ding" ]; then ding=t; else ding=nil; fi
run "$DVDRIP_UPLOAD"
case $eject in t) run eject "$dev" ;; esac
case $ding in
  t)
    if [ -t 1 ]; then exec 3>&1
    elif [ -t 2 ]; then exec 3>&2
    else exec 3>/dev/tty
    fi
    printf "\a" >&3
    exec 3>&-
    ;;
esac