#!/usr/bin/env bash
#
# lsb_release - collect LSB conformance status about a system
#
# Copyright (C) 2000, 2002, 2004 Free Standards Group, Inc.
# Originally by Dominique MASSONIE <mdomi@users.sourceforge.net>
# Modified for SUSE Linux products by Thorsten Kukuk
#
# Copyright (C) 2023 Nedko Arnaudov
# Modified for LADIOS (LADI project)
#
# 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.
#
# 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 should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Description:
# Collect information from sourceable /etc/lsb-release file (present on
# LSB-compliant systems) : LSB_VERSION, DISTRIB_ID, DISTRIB_RELEASE,
# DISTRIB_CODENAME, DISTRIB_DESCRIPTION (all optional)
# Then (if needed) find and add names from /etc/lsb-release.d


###############################################################################
#     DECLARATIONS
###############################################################################

# This script version
SCRIPTVERSION="3.1-LADI"

# Defines the data files
INFO_LSB_FILE="/etc/lsb-release"              # where to get LSB version
INFO_LSB_DIR="/etc/lsb-release.d"             # where to get LSB addon modules
INFO_DISTRIB_FILE="/etc/os-release"           # <distrib>-<suffix>

# Defines our exit codes
EXIT_STATUS="0"                           # default = Ok :)
ERROR_UNKNOWN="10"                        # unknown error
ERROR_USER="1"                            # program misuse
ERROR_PROGRAM="2"                         # internal error
ERROR_NOANSWER="3"                        # all required info not available
                                          # typically non LSB compliant distro!

# Defines our messages
MSG_LSBVER="LSB Version:\t"
MSG_DISTID="Distributor ID:\t"
MSG_DISTDESC="Description:\t"
MSG_DISTREL="Release:\t"
MSG_DISTCODE="Codename:\t"
MSG_HOMEPAGE_URL="WWW Homepage:\t"
MSG_SUPPORT_URL="Support:\t"
MSG_BUGREPORT_URL="Bug reports:\t"
MSG_LOWERCASE_DISTID="Lowercase Name:\t"
MSG_NA="n/a"
MSG_NONE="(none)"
MSG_RESULT="" # contains the result in case short output selected
MSG_DISTRIBUTOR=""

###############################################################################
#     FUNCTIONS
###############################################################################

# Display Program Version for internal use (needed by help2man)
DisplayProgramVersion() {
    echo "$(basename "$0") v$SCRIPTVERSION"
    echo
    echo "Copyright (C) 2000, 2002, 2004 Free Standards Group, Inc."
    echo "Copyright (C) 2017 SUSE Linux GmbH"
    echo "Copyright (C) 2022 SUSE Software Solutions Germany GmbH"
    echo "Copyright (C) 2023 Nedko Arnaudov"
    echo
    echo "This is free software; see the source for copying conditions.  There is NO"
    echo "warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE."
    echo
    echo "Originally written by Dominique MASSONIE."

    exit $EXIT_STATUS
}

# defines the Usage for lsb_release
Usage() {
    echo "$(basename "$0") v$SCRIPTVERSION prints certain LSB (Linux Standard Base) and"
    echo "Distribution information."
    echo
    echo "Usage: $(basename "$0") [OPTION]..."
    echo "With no OPTION specified defaults to -v."
    echo
    echo "Options:"
    echo "  -v, --version"
    echo "    Display the version of the LSB specification against which the distribution is compliant."
    echo "  -i, --id"
    echo "    Display the string id of the distributor."
    echo "  -d, --description"
    echo "    Display the single line text description of the distribution."
    echo "  -r, --release"
    echo "    Display the release number of the distribution."
    echo "  -c, --codename"
    echo "    Display the codename according to the distribution release."
    echo "  -w, --homepage"
    echo "    Display the distribution WWW homepage URL."
    echo "  -u, --support"
    echo "    Display the distribution sUpport URL."
    echo "  -b, --bugreport"
    echo "    Display the distribution Bugreport URL."
    echo "  -n,--lowercase_name"
    # '(echo $(lsb_release -is)-$(lsb_release -rs) | tr "[:upper:]" "[:lower:]")'
    echo "    Display the distro lowercase name (with revision)."
    echo "  -a, --all"
    echo "    Display all of the above information."
    echo "  -s, --short"
    echo "    Use short output format for information requested by other options (or version if none)."
    echo "  -h, --help"
    echo "    Display this message."

    exit $EXIT_STATUS
}

# Handles the enhanced args (i.e. --something)
EnhancedGetopt() {
    getopt -T >/dev/null 2>&1             # is getopt the enhanced one ?
    if [ $? = 4 ]
    then                                  # Yes, advanced args ALLOWED
        OPT=$(getopt -o acdhirsvpwubn                                         \
--long all,codename,description,help,id,release,short,version,program_version,\
homepage,support,bugreport,lowercase_name \
              -n 'lsb_release'                                                \
              -- "$@")
    else                                  # No, advanced args NOT allowed
        # convert (if needed) the enhanced options into basic ones
        MYARGS=$(echo "$@" | sed -e "/--/s/-\(-[[:alnum:]]\)[[:alnum:]]*/\1/g")
        OPT=$(getopt -o acdhirsvpwubb                                         \
                     -n 'lsb_release'                                         \
                     -- "$MYARGS")
    fi
    if [ $? != 0 ]
    then
        exit $ERROR_PROGRAM
    fi

    NB_ARG=""       # enabled if many args set in one parameter (i.e. -dris)
    eval set -- "$OPT"
    while true ; do
        case "$1" in
        -a|--all) ARG_A="y"; NB_ARG="y"; shift;;
        -c|--codename) ARG_C="y"; NB_ARG="y"; shift;;
        -d|--description) ARG_D="y"; NB_ARG="y"; shift;;
        -i|--id) ARG_I="y"; NB_ARG="y"; shift;;
        -r|--release) ARG_R="y"; NB_ARG="y"; shift;;
        -w|--homepage) ARG_W="y"; shift;;
        -u|--support) ARG_U="y"; shift;;
        -b|--bugreport) ARG_B="y"; shift;;
        -n|--lowecase_name) ARG_N="y"; shift;;
        -s|--short) ARG_S="y"; shift;;
        -v|--version) ARG_V="y"; NB_ARG="y"; shift;;
        -p|--program_version) DisplayProgramVersion;;
	-h|--help) Usage;;
        --) shift; break;;
        *)  EXIT_STATUS=$ERROR_USER
            Usage;;
        esac
    done
}

# Get/Init LSB infos (maybe Distrib infos too)
GetLSBInfo() {
    LSB_VERSION=""
    if [ -f "$INFO_LSB_FILE" ]
    then
        # should init at least LSB_VERSION
        . "$INFO_LSB_FILE"
    fi
    # Always look in the directories
    if [ -d "$INFO_ROOT/$INFO_LSB_DIR" ]
    then
	for tag in "$INFO_ROOT/$INFO_LSB_DIR/"*
	do
	    if [ -z "$LSB_VERSION" ]
	    then
	        LSB_VERSION=$(basename "$tag")
	    else
		LSB_VERSION=$LSB_VERSION:$(basename "$tag")
	    fi
	done
    fi
    if [ -z "$LSB_VERSION" ]
    then
	LSB_VERSION=$MSG_NA
    fi
}

# Get the whole distrib information string (from /etc/os-release)
InitDistribInfo() {

    . $INFO_DISTRIB_FILE
    NO=""                    # is Description string syntax correct ?

    if [ -z "$DISTRIB_DESCRIPTION" ]; then
	if [ -n "$PRETTY_NAME" ]; then
            DISTRIB_DESCRIPTION=$PRETTY_NAME
	else
            DISTRIB_DESCRIPTION=$MSG_NONE
	fi
    fi

    if [ -z "$DISTRIB_ID" ]; then
	if [ -n "$MSG_DISTRIBUTOR" ]; then
	    DISTRIB_ID=$MSG_DISTRIBUTOR
	else
	    case "$PRETTY_NAME" in
		Fedora*)
		    DISTRIB_ID="Fedora"
		    ;;
		CentOS*)
		    DISTRIB_ID="CentOS"
		    ;;
		"Red Hat Enterprise Linux"*)
		    DISTRIB_ID="RedHatEnterprise"
		    ;;
		AlmaLinux*)
		    DISTRIB_ID="AlmaLinux"
		    ;;
		Oracle*)
		    DISTRIB_ID="OracleLinux"
		    ;;
		openSUSE*)
		    DISTRIB_ID="openSUSE"
		    ;;
		SUSE*)
		    DISTRIB_ID="SUSE"
		    ;;
		*)
		    DISTRIB_ID=$MSG_NA
		    ;;
	    esac
	fi
    fi

    if [ -z "$DISTRIB_RELEASE" ]; then
	if [ -n "$VERSION_ID" ]; then
            DISTRIB_RELEASE=$VERSION_ID
	else
            DISTRIB_RELEASE=$MSG_NA
	fi
    fi

    if [ -z "$DISTRIB_CODENAME" ]; then
	if [ -n "$VERSION_CODENAME" ]; then
            DISTRIB_CODENAME=$VERSION_CODENAME
	else
            DISTRIB_CODENAME=$MSG_NA
	fi
    fi
}

# Check missing and requested infos, then find the file and get infos
GetDistribInfo() {
    NO=""  # /etc/lsb-release data are enough to reply what is requested?
    [ -n "$ARG_D" ] && [ -z "$DISTRIB_DESCRIPTION" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_I" ] && [ -z "$DISTRIB_ID" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_R" ] && [ -z "$DISTRIB_RELEASE" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_N" ] && [ -z "$DISTRIB_RELEASE" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_W" ] && [ -z "$HOME_URL" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_U" ] && [ -z "$SUPPORT_URL" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_B" ] && [ -z "$BUG_REPORT_URL" ] && NO="y"
    [ -z "$NO" ] && [ -n "$ARG_C" ] && [ -z "$DISTRIB_CODENAME" ] && NO="y"

    if [ -n "$NO" ]
    then
        InitDistribInfo
    fi
}

# Display version of LSB against which distribution is compliant
DisplayVersion() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_LSBVER$LSB_VERSION"          # at least "n/a"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$LSB_VERSION"
    fi
}

# Display string id of distributor ( i.e. a single word! )
DisplayID() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTID$DISTRIB_ID"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$DISTRIB_ID"
    fi
}

# Diplay single line text description of distribution
DisplayDescription() {
    if [ -z "$DISTRIB_DESCRIPTION" ]
    then
        # should not be empty since GetDistribInfo called on Initialization !
        EXIT_STATUS=$ERROR_PROGRAM
    fi
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTDESC$DISTRIB_DESCRIPTION"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }\"$DISTRIB_DESCRIPTION\""
    fi
}

# Display release number of distribution.
DisplayRelease() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTREL$DISTRIB_RELEASE"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$DISTRIB_RELEASE"
    fi
}

# Display codename according to distribution version.
DisplayCodename() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_DISTCODE$(echo "$DISTRIB_CODENAME" |                    \
                                tr -d "[:blank:]")" # Remove blanks
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$(echo "$DISTRIB_CODENAME" |   \
                                                 tr -d "[:blank:]")"
    fi
}

# Display the distribution WWW homepage URL
DisplayHomepageURL() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_HOMEPAGE_URL${HOME_URL}"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }${HOME_URL}"
    fi
}

# Display the distribution sUpport URL
DisplaySupportURL() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_SUPPORT_URL${SUPPORT_URL}"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }${SUPPORT_URL}"
    fi
}

# Display the distribution Bugreport URL
DisplayBugreportURL() {
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_BUGREPORT_URL${BUG_REPORT_URL}"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }${BUG_REPORT_URL}"
    fi
}

DisplayLowercaseID() {
    # '(echo $(lsb_release -is)-$(lsb_release -rs) | tr "[:upper:]" "[:lower:]")'
    LOWERCASE_DISTRIB_ID=$(echo $DISTRIB_ID | tr "[:upper:]" "[:lower:]")-$DISTRIB_RELEASE
    if [ -z "$ARG_S" ]
    then
        echo -e "$MSG_LOWERCASE_DISTID$LOWERCASE_DISTRIB_ID"
    else
        MSG_RESULT="$MSG_RESULT${MSG_RESULT:+ }$LOWERCASE_DISTRIB_ID"
    fi
}

###############################################################################
#     MAIN
###############################################################################

# Check if any prog argument
if [ -z "$1" ]
then
    ARG_V="y"           # default set to Display LSB Version (not Usage)
else
    EnhancedGetopt "$@" # Parse program args
    if [ -n "$ARG_S" ] && [ -z "$NB_ARG" ]
    then
        ARG_V="y"       # set also default for --short when single arg
    fi
fi

# Update args to All if requested
if [ -n "$ARG_A" ]
then
    [ -z "$ARG_C" ] && ARG_C="y"
    [ -z "$ARG_D" ] && ARG_D="y"
    [ -z "$ARG_I" ] && ARG_I="y"
    [ -z "$ARG_R" ] && ARG_R="y"
    [ -z "$ARG_V" ] && ARG_V="y"
    [ -z "$ARG_W" ] && ARG_W="y"
    [ -z "$ARG_U" ] && ARG_U="y"
    [ -z "$ARG_B" ] && ARG_B="y"
    [ -z "$ARG_N" ] && ARG_N="y"
fi

# Initialization
GetLSBInfo
GetDistribInfo

# Display requested infos (order as follow)
[ -n "$ARG_V" ] && DisplayVersion
[ -n "$ARG_I" ] && DisplayID
[ -n "$ARG_D" ] && DisplayDescription
[ -n "$ARG_R" ] && DisplayRelease
[ -n "$ARG_C" ] && DisplayCodename
[ -n "$ARG_W" ] && DisplayHomepageURL
[ -n "$ARG_U" ] && DisplaySupportURL
[ -n "$ARG_B" ] && DisplayBugreportURL
[ -n "$ARG_N" ] && DisplayLowercaseID

[ -n "$ARG_S" ] && echo "$MSG_RESULT"

exit $EXIT_STATUS