#!/bin/sh
#----------------------------------------------------------------------------
# /var/install/bin/convert-encoding - convert UTF-8 <-> ISO-8859
#
# Creation:     2013-09-24 hbfl
# Last Update:  $Id$
#
# Copyright (c) 2013-@@YEAR@@ the eisfair team, team(at)eisfair(dot)org
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#----------------------------------------------------------------------------


# ---------------------------------------------------------------------------
# usage
# ---------------------------------------------------------------------------
usage ()
{
cat <<EOF

 Usage:
 ${0}

                [filename]

                Example:  convert-encoding "/usr/share/doc/lprng/lprng.txt"
EOF
}
# ---------------------------------------------------------------------------
# get system encoding
# ---------------------------------------------------------------------------
get_system_encoding()
{
    # get LC_CTYPE entry
    _s_encoding=$(grep '^LC_CTYPE' /etc/config.d/environment |
                       sed  "s/^.*=['\"]\(.*\)['\"].*$/\1/")

    # check _s_encoding for .utf8|.utf-8
    if echo "${_s_encoding}" | grep -qE '.[Uu][Tt][Ff]-?8'
    then
        _system_encoding='UTF-8'
    else
        _system_encoding='ISO_8859-15'
    fi
}
# ---------------------------------------------------------------------------
# get file encoding
# ---------------------------------------------------------------------------
get_file_encoding()
{
    __conf_file="${1}"

    # extract file parameter
    if file --help | grep -q 'mime-encoding'
    then
        _opt1='--mime-encoding'
        _opt2=''
    else
        _opt1='--mime'
        _opt2='| cut -d= -f2'
    fi

    # get file encoding
    _f_encoding="$(file -b ${_opt1} "${__conf_file}" ${_opt2})"

    # check _f_encoding for UTF-8
    if [ "${_f_encoding}" = "utf-8" ]
    then
        _file_encoding="UTF-8"
    else
        _file_encoding="ISO_8859-15"
    fi
}
# ---------------------------------------------------------------------------
# convert file encoding
# ---------------------------------------------------------------------------
convert_file_encoding()
{
    __conf_file="${1}"

    # convert given file if non equal
    if [ ${_file_encoding} != ${_system_encoding} ]
    then
        _tmp_file=$(mktemp -t .XXXXXXXXXXXXX)
        iconv -f ${_file_encoding} -t ${_system_encoding} -o ${_tmp_file} ${__conf_file}
        mv -f  ${_tmp_file} ${__conf_file}
    fi
}
# ---------------------------------------------------------------------------
# main
# ---------------------------------------------------------------------------

# check for cmd line input
if [ ${#} -eq 0 ]
then
    usage
    exit 1
fi

while [ ${#} -ne 0 ]
do
    case ${1} in
    -h|--help)
        usage
        shift
        exit 1
        ;;
    *)
        _conf_file="${1}"
        shift
        ;;
    esac
done

if [ -f "${_conf_file}" ]
then
    get_system_encoding

    get_file_encoding "${_conf_file}"

    convert_file_encoding "${_conf_file}"
fi

exit 0
# ---------------------------------------------------------------------------
# end
# ---------------------------------------------------------------------------