#!/bin/sh
#
# po4a-display-man shows a translated manpage, recompiling everything on the fly with po4a.
# Translators can see the effects of their work without reinstalling everything.
#

OPTIONS=""

usage() {
  echo "Usage: $0 -p PO_FILE [-m MASTER_FILE] [-o PO4A_OPT]"
  return 0
}

error () {
  echo "Error: $1" 1>&2
  exit 1
}

while getopts m:p:ho: option
do
  case $option in
    m)
      MASTER="$OPTARG"
      ;;
    p)
      PO="$OPTARG"
      ;;
    o)
      OPTIONS="$OPTIONS $OPTARG"
      ;;
    h)
      usage
      exit 0
      ;;
    [?])
      usage 1>&2
      exit 1
      ;;
  esac
done

if [ -z "$PO" ]
then
  usage 1>&2
  exit 1
fi

if [ ! -f "$PO" ]
then
  error "could not find PO file: $PO"
fi

if [ -z "$MASTER" ]
then
  echo "No manpage specified."
  echo "Trying to find the manpage according to a line reference in the PO."
  MASTER=$(grep -m 1 "^#:" $PO | sed -e 's/^.* \(.*\):.*$/\1/')
fi

find_man()
{
  section="$1"
  man="$2"
  echo -n "Looking for manpage $file"
  [ -n "$section" ] && echo " in section $section" || echo ""
  MAN_NUMBER=`man --all --where --locale=C $section "$man" 2> /dev/null | wc -l`

  if [ "$MAN_NUMBER" = "0" ]
  then
    return 1
  elif [ "$MAN_NUMBER" != "1" ]; then
    MAN_NUMBER=`man --all --where --locale=C $section "$man" 2> /dev/null | \
                grep "\/$man\.$section\(.gz\)\?$" | wc -l`
    if [ "$MAN_NUMBER" = "1" ]
    then
      MASTER=`man --where --locale=C "$section" "$man" | grep "\/$man\.$section\(.gz\)\?$"`
      echo "Multiple manpages in section $section: $(man -aw -L C $section "$man"), only one exactly matches the section."
    else
      error "Too many possible manpages: $(man -aw -L C $section "$man"), you must specify the manpage or the section"
    fi
  else
    MASTER=`man --where --locale=C "$section" "$man"`
  fi

  return 0
}

if [ ! -f "$MASTER" ]
then
  echo "Can't find the master man page $MASTER"
  file=$(basename "$MASTER")
  MASTER=""
  section=""
  if ! find_man "" "$file"
  then
    # Maybe $file contains a section
    # (in the form of file.section.extension)
    section=$(echo "$file" | sed -ne 's/^.*\.\([1-9].*\)$/\1/; s/\..*//; p')
    file=$(echo "$file" | sed -e 's/\.[1-9].*//')
    if ! find_man "$section" "$file"
    then
      # Maybe there is an extension at the end of the manpage (e.g. .man)
      file=$(echo "$file" | sed -e 's/\..*//')
      if ! find_man "$section" "$file"
      then
        echo "No manpage found"
        echo "You must provide the manpage with the -m option"
        MASTER=""
      fi
    fi
  fi
  if [ -n "$MASTER" ]
  then
    echo "Using: $MASTER as the original manpage"
  fi
fi

# checking mandatory options
if [ -z "$MASTER" ]
then
  usage 1>&2
  exit 1
fi

# checking files
if [ ! -e "$MASTER" ]
then
  error "could not find master file: $MASTER"
fi


if [ "${MASTER%.gz}" = "$MASTER" ]
then
  MAINNAME="$MASTER"
else
  MAINNAME=`mktemp`
  trap "rm \"$MAINNAME\"" EXIT INT
  gunzip -c "$MASTER" > "$MAINNAME"
fi

CHARSET_MASTER=`file -i "$MAINNAME" | cut -d "=" -f 2`
CHARSET_PO=`file -i "$PO" | cut -d "=" -f 2`

po4a-translate -f man -k 0 -m "$MAINNAME" -M "$CHARSET_MASTER" \
  -p "$PO" $OPTIONS| iconv -f "$CHARSET_PO" -t // | man -l -

# TODO: man may need some options (e.g. -L)
#       as we cannot detect what options are needed, they will have to be
#       specified on the po4a-display-man command line.