#!/bin/bash

# Copyright (C) 2020  Canonical Ltd.
# Author: Iain Lane <iain.lane@canonical.com>

# 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, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

# Compare a given source package with the oem-qemu-meta reference package, to
# see if it complies with the MIR exception granted in
# https://wiki.ubuntu.com/MIRTeam/Exceptions/OEM

set -e
set -u

shopt -s nullglob

THIS="$(basename "${0}")"

ensure_programs() {
    if [ ${#} -gt 0 ] && ! type "${1}" >/dev/null 2>/dev/null; then
        echo "Required program $1 not found." >&2
        exit 1
    fi

    shift

    if [ ${#} -gt 0 ]; then
        ensure_programs "${@}"
    fi
}

if [ ${#} -ne 1 ]; then
        echo -e "Usage: ${THIS} <dsc>\\n" >&2
        cat <<EOM >&2
Compare the given package against the oem-qemu-meta reference package. Check
that all the differences are inconsequential or expected (different modalias,
different package name), and then promote or NEW the package directly to main.

https://wiki.ubuntu.com/MIRTeam/Exceptions/OEM
EOM
        exit 1
fi

ensure_programs pull-lp-source debdiff

if ! [ -e "${1}" ]; then
    echo "${THIS}: ${1} not found" >&2
    exit 1
fi

DSC="$(realpath -e "${1}")"

WORKINGDIR=$(mktemp -d)

trap 'rm -rf ${WORKINGDIR}' EXIT HUP INT QUIT TERM

pushd "${WORKINGDIR}" >/dev/null

# Download the reference package
pull-lp-source oem-qemu-meta -d 2>/dev/null

if [ -t 1 ] && type colordiff >/dev/null 2>/dev/null; then
        debdiff oem-qemu-meta_*.dsc "${DSC}" 2>/dev/null | colordiff
else
        debdiff oem-qemu-meta_*.dsc "${DSC}" 2>/dev/null
fi