#!/bin/bash -u

#

# Extracts what appears to be the value of %{dist} from the commit message

#

# Might want to drop this in ~/bin/ and chmod u+x it

#####################################################################

usage() {

    echo ''                                               >&2

    echo "$0 [-hr]"                                       >&2

    echo ''                                               >&2

    echo ' -h: This help message'                         >&2

    echo ' -r: Use the Redhat tag rather than centos tag' >&2

    echo ' -q: Suppress warnings'                         >&2

    echo ''                                               >&2

    echo '  Attempt to extract what appears to be the value of %{dist}' >&2

    echo '  from the git.centos.org commit message'       >&2

    exit 1

}

#####################################################################

# setup args in the right order for making getopt evaluation

# nice and easy.  You'll need to read the manpages for more info

args=$(getopt -o hrq -- "$@")

if [[ $? -ne 0 ]]; then

    usage

fi

eval set -- "$args"

RHELTAG=0

QUIET=0

for arg in "$@"; do

    case $1 in

        -- )

            # end of getopt args, shift off the -- and get out of the loop

            shift

            break 2

           ;;

         -r )

            # skip any package with 'centos' in the dist area

            RHELTAG=1

           ;;

         -q )

            # suppress warnings

            QUIET=1

           ;;

         -h )

            # get help

            usage

           ;;

    esac

done

warn () {

    [[ ${QUIET} -eq 1 ]] && return

    echo 1>&2 "$@"

}

if [[ ! -d .git ]] || [[ ! -d SPECS ]]; then

    echo 'You need to run this from inside a sources git repo'

    exit 1

fi

# check metadata file and extract package name

packagename=""

shopt -s nullglob

for fn in .*.metadata

do

    pn=${fn%.metadata}

    pn=${pn#.}

    if [ -e "SPECS/$pn.spec" ]

    then

        packagename="$pn"

        break

    fi

done

if [ -z "$packagename" ]

then

    echo 'Missing metadata or spec. Please run from inside a sources git repo'

    exit 1

fi

filter () {

    # filter used for log messages

    if [[ ${RHELTAG} -eq 1 ]]

    then

        grep -v centos | grep import

    else

        grep import

    fi

}

# extract nvr from commit message of last import

msg=$(git log --pretty=format:"%s" | filter | head -n 1)

set -- $msg

pkg="$2"

# strip .src.rpm if present

nvr1="${pkg%.src.rpm}"

#now get nvr from spec with placeholder dist

mydist="XXXjsdf9ur7qlkasdh4gygXXX"

nvr2=$(rpm --define "dist $mydist" -q --specfile "SPECS/$packagename.spec" --qf '%{n}-%{v}-%{r}\n' 2>/dev/null | head -n 1)

#use our placeholder dist to split the nvr

head=${nvr2%$mydist*}

if [ ".$head" = ".$nvr2" ]

then

    #no dist tag

    echo ""

    exit

fi

tail=${nvr2#*$mydist}

frag=${nvr1#$head}

dist=${frag%$tail}

# sanity check

nvr3=$(rpm --define "dist $dist" -q --specfile "SPECS/$packagename.spec" --qf '%{n}-%{v}-%{r}\n' 2>/dev/null | head -n 1)

if [ ".$nvr3" != ".$nvr1" ]

then

    warn "Warning: $nvr3 != $nvr1"

    warn "Warning: check failed. The %{dist} value may be incorrect"

fi

echo "$dist"