#! /bin/sh
#  iscan-registry.in -- adds/removes information from "sub"packages
#  Copyright (C) 2008  SEIKO EPSON CORPORATION
#
#  License: GPLv2+
#  Authors: AVASYS CORPORATION
#
#  This file is part of the 'Image Scan! for Linux' package.
#  This package 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.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#  You ought to have received a copy of the GNU General Public License
#  along with this package.  If not, see <http://www.gnu.org/licenses/>.


STATEDIR=@PKGLOCALSTATEDIR@

#  Output a version blurb.

version () {
    cat <<EOF
`basename $0` (@PACKAGE_NAME@) @PACKAGE_VERSION@
Copyright (C) 2008  @scm_src_vendor@
This is free software.  You may redistribute copies of it under the
terms of the GNU General Public License, version 2 or later.
See <http://www.gnu.org/licenses/gpl.html> for details.

Written by @scm_src_author@.
EOF
    if test xyes = x$1; then
        echo
        usage
    fi
    exit
}

#  Shows script usage documentation and exits the program with the
#  optional status passed as its first argument.

usage () {
    cat <<EOF
'`basename $0`' updates the run-time data for @PACKAGE_NAME@

Usage: $0 --help | --version
       $0 --add <spec>
       $0 --remove <spec>

@PACKAGE_NAME@ plugins may need to (un)register themselves.
This utility gives plugins a common interface to do just that.  You
should not need to use this utility manually.

The following options are supported:

  -h, --help              displays this message and exit
  -v, --version           displays program version and exit

  -a, --add               adds a plugin to the run-time data
  -r, --remove            removes a plugin from the run-time data

The following <spec>s are supported:

  interpreter usb <vendor-id> <product-id> <plugin> [<firmware>]

The <vendor-id> and <product-id> are the USB IDs in hexadecimal
notation, prefixed with '0x'.  <plugin> and optional <firmware>
are pathnames to the corresponding files.
Note that the <plugin> pathname should not include an extension.
EOF
    exit $1
}

show_help=no
show_vers=no

run_mode=

options=`getopt \
    --options hvar \
    --longopt help,version \
    --longopt add,remove \
    -- "$@"`

if test 0 != $?; then
    echo "`basename $0`: error parsing command line options" >&2
    usage 1
fi

#  Sets and makes sure only a single run mode is specified.

set_run_mode () {
    if test x$run_mode != x; then
        echo "`basename $0`: use only one of --add and --remove" >&2
        exit 1
    fi
    run_mode=$1
}

eval set -- "$options"

while test x-- != "x$1"; do
    case "$1" in
        -h|--help)      show_help=yes; shift;;
        -v|--version)   show_vers=yes; shift;;
        -a|--add)       set_run_mode add; shift;;
        -r|--remove)    set_run_mode remove; shift;;
        *)
            echo "`basename $0`: internal inconsistency"
            exit 1
            ;;
    esac
done
shift                           # past the '--' marker

test xyes = x$show_vers && version $show_help
test xyes = x$show_help && usage

#  If --version or --help was specified, we will have exited by now.

if test x$run_mode = x; then
    echo "`basename $0`: at least one option is required" >&2
    exit 1
fi
if test 5 -gt $# || test 6 -lt $#; then
    echo "`basename $0`: not enough parameters" >&2
    exit 1
fi

#  Validate at least the first argument to avoid making arbitrary
#  files in STATEDIR.

case "$1" in
    interpreter)
        config="$STATEDIR/$1"
        chspec="$1 $2 $3 $4"
        plugin="$5"
        fwfile="$6"
        ;;
    *)
        echo "`basename $0`: $1 not supported" >&2
        exit 1
        ;;
esac


case "$run_mode" in
    add)
        test -d "$STATEDIR" || mkdir -p "$STATEDIR"
        echo "$chspec $plugin $fwfile" >> "$config"
        ;;
    remove)
        test -f "$config" || exit 0
        pattern=`echo "$chspec $plugin $fwfile" | sed 's|/|\\\\/|g'`
        first=`sed -n "/$pattern/{ =; q}" "$config"`
        test -n "${first}" && sed -i "${first}d" "$config"
        ;;
    *)
        echo "`basename $0`: internal inconsistency" >&2
        exit 1
        ;;
esac