#!/bin/sh

set -e
set -x

detect_distro () {
    DISTRO_VENDOR=$(lsb_release --id -s | awk '{print tolower($0)}')
    DISTRO_NAME=$(lsb_release -c -s)
}


# Get some version information out of the debian/changelog last entry
get_deb_version() {
    PKG_NAME=$(dpkg-parsechangelog -SSource)
    DEB_VERS=$(dpkg-parsechangelog -SVersion)
    NO_EPOC=$(echo ${DEB_VERS} | cut -d":" -f2)
    if echo ${DEB_VERS} | grep -q ':' ; then
        EPOC=$(echo ${DEB_VERS} | cut -d":" -f1)
    fi
    UPSTREAM_VERS=$(echo ${NO_EPOC} | cut -d"-" -f1)
    if [ "${DEB_VERS}" = "${UPSTREAM_VERS}" ] ; then IS_NATIVE="yes" ; else IS_NATIVE="no" ; fi
    ORIG=${PKG_NAME}_${UPSTREAM_VERS}.orig.tar.xz
    CHANGE=${PKG_NAME}_${NO_EPOC}_${ARCH}.changes
    PKG_NAME_FIRST_CHAR=$(echo ${PKG_NAME} | awk '{print substr($0,1,1)}')
}

calc_bpo_version () {
    case ${DISTRO_NAME} in
    jessie)
        BPO_DISTRO_NUM="~bpo8+1"
    ;;
    stretch)
        BPO_DISTRO_NUM="~bpo9+1"
    ;;
    buster)
        BPO_DISTRO_NUM="~bpo10+1"
    ;;
    sid)
        BPO_DISTRO_NUM=""
    ;;
    trusty)
        BPO_DISTRO_NUM="~bpo14.04+1"
    ;;
    xenial)
        BPO_DISTRO_NUM="~bpo16.04+1"
    ;;
    *)
        echo "Distribution not supported!"
        echo "Falling back to no changelog bpo version tag"
        BPO_DISTRO_NUM=""
    ;;
    esac
}

create_orig_tarball () {
    if grep pristine-tar debian/gbp.conf | grep -q -i true ; then
        echo "Nothing special to do with Pristine tar: not generating orig file!"
    else
        if [ "${IS_NATIVE}" = "no" ] ; then
            GENORIG_DEBRULES_TARGET=gen-orig-xz
            if [ -r debian/gbp.conf ] ; then
                COMPRESSION_IN_FILE=$(cat debian/gbp.conf | grep compression | cut -d'=' -f2 | awk '{print $1}')
                if [ "${COMPRESSION_IN_FILE}" = "gz" ] ; then
                    GENORIG_DEBRULES_TARGET=gen-orig-gz
                elif [ "${COMPRESSION_IN_FILE}" = "bzip2" ] ; then
                    GENORIG_DEBRULES_TARGET=gen-orig-bz2
                fi
            fi
            ./debian/rules ${GENORIG_DEBRULES_TARGET}
        fi
    fi
}

detect_branch_name () {
	PACKAGING_BRANCH_NAME=$(grep debian-branch debian/gbp.conf | cut -d= -f2 | awk '{print $1}')
}

build_backport_package () {
    echo "===> Building using git-buildpackage"
    # Edit debian/changelog to show we're building a backport
    LAST_GIT_COMMIT=$(git log | head -n 1 | awk '{print $2}')
    NUM_COMMITS_FROM_LAST_TAG=$(git rev-list --no-merges $(git describe --no-abbrev --candidates=1)..HEAD | wc -l)
    DEBFULLNAME="Jenkins" DEBEMAIL=jenkins@openstack.org dch --newversion ${DEB_VERS}+${NUM_COMMITS_FROM_LAST_TAG}${BPO_DISTRO_NUM} -b --allow-lower-version -m  "Backport rebuilt by Jenkins in OpenStack infra."
    git commit debian/changelog -m "Backport rebuilt by Jenkins in OpenStack infra."
    git checkout -b ${PACKAGING_BRANCH_NAME}

    # Create ssh key
    if ! [ -e ~/.ssh/id_rsa ] ; then
    	ssh-keygen -t rsa -N "" -f ~/.ssh/id_rsa
    fi
    # Copy it to authorized_keys
    cat ~/.ssh/id_rsa.pub >>~/.ssh/authorized_keys
    cat ~/.ssh/id_rsa.pub >>~/.ssh/authorized_keys2

    # Build the package with gbp buildpackage
    echo "===> Building with gbp buildpackage from ${WORKSPACE}"
    if [ "${IS_NATIVE}" = "no" ] ; then
        SAFLAG=" --force-orig-source"
    else
        SAFLAG=""
    fi
    if ! ssh -o "StrictHostKeyChecking no" localhost "cd ${WORKSPACE} ; gbp buildpackage${SAFLAG}" ; then
        git reset --hard ${LAST_GIT_COMMIT}
        echo "Error building the package with gbp buildpackage: exiting."
        exit 1
    else
        git reset --hard ${LAST_GIT_COMMIT}
    fi
}

lintian_test_the_package () {
    echo "===> Starting Lintian check"
    lintian -I -E --pedantic --suppress-tags bad-distribution-in-changes-file ../build-area/*.changes
}

prepare_for_upload () {
    # When we switch to zuul v3, we can use this:
    #UPDIR=../uploads
    # Until then, we must stay in the WORKSPACE
    UPDIR=uploads

    mkdir -p ${UPDIR}/${LAST_GIT_COMMIT}
    cp ../build-area/* ${UPDIR}/${LAST_GIT_COMMIT}
    rm ${UPDIR}/${LAST_GIT_COMMIT}/*.build
    cp -auxf ../build-area .
}


# We need this because we don't re-login, and
# sbuild has just been installed:
newgrp - sbuild
# Then we can start...
detect_distro
calc_bpo_version
get_deb_version
create_orig_tarball
detect_branch_name
build_backport_package
lintian_test_the_package
prepare_for_upload
