#!/usr/bin/env bash
# diff sources unpacked by two ebuilds (works only for simple ebuilds)
# (c) 2019-2024 Michał Górny <mgorny@gentoo.org>
# SPDX-License-Identifier: GPL-2.0-or-later

set -e -x

mode=default
while [[ ${#} -gt 0 ]]; do
	case ${1} in
		--all|-a)
			mode=
			;;
		--build-system|-b)
			mode=build-system
			;;
		*)
			break
			;;
	esac
	shift
done

get_category() {
	local dir=.
	[[ ${1} != */* ]] || dir=${1%/*}
	dir=$( cd "${dir}" && pwd )
	dir="${dir%/*}"
	echo "${dir##*/}"
}

cat1=$(get_category "${1}")
cat2=$(get_category "${2}")
fn1=${1##*/}
fn2=${2##*/}
ver1=$(patom -F '%{fullver}' "=${cat1}/${fn1%.ebuild}")
ver2=$(patom -F '%{fullver}' "=${cat2}/${fn2%.ebuild}")

export PORTAGE_TMPDIR="${TMPDIR:-/tmp}"/mgorny-dev-scripts
export USE="${USE} test"
# use noauto to skip pkg_setup
export FEATURES="${FEATURES} noauto"
# tell ebuilds we don't want everything
mkdir -p "${PORTAGE_TMPDIR}"
PKGBUMPING=${ver1} ebuild "${1}" unpack
PKGBUMPING=${ver2} ebuild "${2}" unpack
s1=$(sed -nr 's/^declare -x S="(.*)"/\1/p' "${PORTAGE_TMPDIR}"/portage/${cat1}/${fn1%.ebuild}/temp/environment)
s2=$(sed -nr 's/^declare -x S="(.*)"/\1/p' "${PORTAGE_TMPDIR}"/portage/${cat2}/${fn2%.ebuild}/temp/environment)

[[ -d ${s1} ]]
[[ -d ${s2} ]]

{
	case "${mode}" in
		build-system)
			find "${s1}" "${s2}" -type f \
				! \( \
						-name 'configure.ac' -o \
						-name '*.m4' -o \
						-name 'meson.build' -o \
						-name 'meson.options' -o \
						-name 'meson_options.txt' -o \
						-name '*.cmake' -o \
						-name 'CMakeLists.txt' -o \
						-name 'setup.py' -o \
						-name 'setup.cfg' -o \
						-name 'pyproject.toml' -o \
						-name 'Makefile.PL' -o \
						-name 'Build.PL' -o \
						-name 'dist.ini' -o \
						-name 'META.yml' -o \
						-name 'META.json' -o \
						-name 'NEWS*' -o \
						-name 'CHANGES*' -o \
						-name 'CHANGELOG*' -o \
						-name 'Gemfile' -o \
						-name 'Gemfile.lock' -o \
						-name 'META' -o \
						-name '*.opam' -o \
						-name 'opam' -o \
						-name 'dune' -o \
						-name 'dune-project' -o \
						-name 'LICENSE*' -o \
						-name 'COPYING*' -o \
						-name 'SConscript' -o \
						-name 'SConstruct' -o \
						-name 'Cargo.lock' -o \
						-name 'Cargo.toml' \
				\) -printf "%f\n"
			;;
		default)
			find "${s1}" "${s2}" -type f \
				\( \
					-name '*.min.*' -o \
					-name 'searchindex.js' \
				\) -printf "%f\n"
			;;
	esac
} | diff --color=always --exclude=".git" --strip-trailing-cr -X - -dupNr "${s1}" "${s2}" | ${PAGER:-less}
