#!/bin/bash
#
# SPDX-License-Identifier: GPL-3.0-or-later

#!/hint/bash
#
# This may be included with or without `set -euE`
#
# SPDX-License-Identifier: GPL-3.0-or-later

[[ -z ${_INCLUDE_COMMON_SH:-} ]] || return 0
_INCLUDE_COMMON_SH="$(set +o|grep nounset)"

set +u +o posix
# shellcheck disable=1091
. /usr/share/makepkg/util.sh
$_INCLUDE_COMMON_SH

# Avoid any encoding problems
export LANG=C

# Set buildtool properties
export BUILDTOOL=devtools
export BUILDTOOLVER=20221002-1-any

# check if messages are to be printed using color
if [[ -t 2 && "$TERM" != dumb ]]; then
	colorize
else
	# shellcheck disable=2034
	declare -gr ALL_OFF='' BOLD='' BLUE='' GREEN='' RED='' YELLOW=''
fi

stat_busy() {
	local mesg=$1; shift
	# shellcheck disable=2059
	printf "${GREEN}==>${ALL_OFF}${BOLD} ${mesg}...${ALL_OFF}" "$@" >&2
}

stat_done() {
	# shellcheck disable=2059
	printf "${BOLD}done${ALL_OFF}\n" >&2
}

_setup_workdir=false
setup_workdir() {
	[[ -z ${WORKDIR:-} ]] && WORKDIR=$(mktemp -d --tmpdir "${0##*/}.XXXXXXXXXX")
	_setup_workdir=true
	trap 'trap_abort' INT QUIT TERM HUP
	trap 'trap_exit' EXIT
}

cleanup() {
	if [[ -n ${WORKDIR:-} ]] && $_setup_workdir; then
		rm -rf "$WORKDIR"
	fi
	exit "${1:-0}"
}

abort() {
	error 'Aborting...'
	cleanup 255
}

trap_abort() {
	trap - EXIT INT QUIT TERM HUP
	abort
}

trap_exit() {
	local r=$?
	trap - EXIT INT QUIT TERM HUP
	cleanup $r
}

die() {
	(( $# )) && error "$@"
	cleanup 255
}

##
#  usage : lock( $fd, $file, $message, [ $message_arguments... ] )
##
lock() {
	# Only reopen the FD if it wasn't handed to us
	if ! [[ "/dev/fd/$1" -ef "$2" ]]; then
		mkdir -p -- "$(dirname -- "$2")"
		eval "exec $1>"'"$2"'
	fi

	if ! flock -n "$1"; then
		stat_busy "${@:3}"
		flock "$1"
		stat_done
	fi
}

##
#  usage : slock( $fd, $file, $message, [ $message_arguments... ] )
##
slock() {
	# Only reopen the FD if it wasn't handed to us
	if ! [[ "/dev/fd/$1" -ef "$2" ]]; then
		mkdir -p -- "$(dirname -- "$2")"
		eval "exec $1>"'"$2"'
	fi

	if ! flock -sn "$1"; then
		stat_busy "${@:3}"
		flock -s "$1"
		stat_done
	fi
}

##
#  usage : lock_close( $fd )
##
lock_close() {
	local fd=$1
	# https://github.com/koalaman/shellcheck/issues/862
	# shellcheck disable=2034
	exec {fd}>&-
}

##
# usage: pkgver_equal( $pkgver1, $pkgver2 )
##
pkgver_equal() {
	if [[ $1 = *-* && $2 = *-* ]]; then
		# if both versions have a pkgrel, then they must be an exact match
		[[ $1 = "$2" ]]
	else
		# otherwise, trim any pkgrel and compare the bare version.
		[[ ${1%%-*} = "${2%%-*}" ]]
	fi
}

##
#  usage: find_cached_package( $pkgname, $pkgver, $arch )
#
#    $pkgver can be supplied with or without a pkgrel appended.
#    If not supplied, any pkgrel will be matched.
##
find_cached_package() {
	local searchdirs=("$PWD" "$PKGDEST") results=()
	local targetname=$1 targetver=$2 targetarch=$3
	local dir pkg packages pkgbasename name ver rel arch r results

	for dir in "${searchdirs[@]}"; do
		[[ -d $dir ]] || continue

		shopt -s extglob nullglob
		mapfile -t packages < <(printf "%s\n" "$dir"/*.pkg.tar?(.!(sig|*.*)))
		shopt -u extglob nullglob

		for pkg in "${packages[@]}"; do
			[[ -f $pkg ]] || continue

			# avoid adding duplicates of the same inode
			for r in "${results[@]}"; do
				[[ $r -ef $pkg ]] && continue 2
			done

			# split apart package filename into parts
			pkgbasename=${pkg##*/}
			pkgbasename=${pkgbasename%.pkg.tar*}

			arch=${pkgbasename##*-}
			pkgbasename=${pkgbasename%-"$arch"}

			rel=${pkgbasename##*-}
			pkgbasename=${pkgbasename%-"$rel"}

			ver=${pkgbasename##*-}
			name=${pkgbasename%-"$ver"}

			if [[ $targetname = "$name" && $targetarch = "$arch" ]] &&
					pkgver_equal "$targetver" "$ver-$rel"; then
				results+=("$pkg")
			fi
		done
	done

	case ${#results[*]} in
		0)
			return 1
			;;
		1)
			printf '%s\n' "${results[0]}"
			return 0
			;;
		*)
			error 'Multiple packages found:'
			printf '\t%s\n' "${results[@]}" >&2
			return 1
	esac
}


check_package_validity(){
	local pkgfile=$1
	if grep -q "packager = Unknown Packager" <(bsdtar -xOqf "$pkgfile" .PKGINFO); then
		die "PACKAGER was not set when building package"
	fi
	hashsum=sha256sum
	pkgbuild_hash=$(awk -v"hashsum=$hashsum" -F' = ' '$1 == "pkgbuild_"hashsum {print $2}' <(bsdtar -xOqf "$pkgfile" .BUILDINFO))
	if [[ "$pkgbuild_hash" != "$($hashsum PKGBUILD|cut -d' ' -f1)" ]]; then
		die "PKGBUILD $hashsum mismatch: expected $pkgbuild_hash"
	fi
}


# usage: grep_pkginfo pkgfile pattern
grep_pkginfo() {
	local _ret=()
	mapfile -t _ret < <(bsdtar -xOqf "$1" ".PKGINFO" | grep "^${2} = ")
	printf '%s\n' "${_ret[@]#${2} = }"
}


# Get the package name
getpkgname() {
	local _name

	_name="$(grep_pkginfo "$1" "pkgname")"
	if [[ -z $_name ]]; then
		error "Package '%s' has no pkgname in the PKGINFO. Fail!" "$1"
		exit 1
	fi

	echo "$_name"
}


# Get the package base or name as fallback
getpkgbase() {
	local _base

	_base="$(grep_pkginfo "$1" "pkgbase")"
	if [[ -z $_base ]]; then
		getpkgname "$1"
	else
		echo "$_base"
	fi
}


getpkgdesc() {
	local _desc

	_desc="$(grep_pkginfo "$1" "pkgdesc")"
	if [[ -z $_desc ]]; then
		error "Package '%s' has no pkgdesc in the PKGINFO. Fail!" "$1"
		exit 1
	fi

	echo "$_desc"
}


is_debug_package() {
	local pkgfile=${1} pkgbase pkgname pkgdesc
	pkgbase="$(getpkgbase "${pkgfile}")"
	pkgname="$(getpkgname "${pkgfile}")"
	pkgdesc="$(getpkgdesc "${pkgfile}")"
	[[ ${pkgdesc} == "Detached debugging symbols for "* && ${pkgbase}-debug = "${pkgname}" ]]
}


usage() {
    cat <<- _EOF_
		Usage: ${BASH_SOURCE[0]##*/} [OPTIONS]

		Searches for a locally built package corresponding to the PKGBUILD, and
		downloads the last version of that package from the Pacman repositories.
		It then compares the list of .so files provided by each version of the
		package and outputs if there are soname differences for the new package.
		A directory is also created using mktemp with files containing a file
		list for both packages and a library list for both packages.

		OPTIONS
		    -r, --rmdir          Remove the temporary directory
		    -w, --warn           Print a warning in case of differences
		    -M, --makepkg-config Set an alternate makepkg configuration file
		    -h, --help           Show this help text
_EOF_
}

RMDIR=0
WARN=0
MAKEPKG_CONF=/etc/makepkg.conf

# option checking
while (( $# )); do
	case $1 in
		-h|--help)
			usage
			exit 0
			;;
		-r|--rmdir)
			RMDIR=1
			shift
			;;
		-w|--warn)
			WARN=1
			shift
			;;
		-M|--makepkg-config)
			MAKEPKG_CONF="$2"
			shift 2
			;;
		--)
			shift
			break
			;;
		-*|--*)
			die "invalid argument: %s" "$1"
			;;
		*)
			break
			;;
	esac
done

# Source makepkg.conf; fail if it is not found
if [[ -r "${MAKEPKG_CONF}" ]]; then
	# shellcheck source=config/makepkg/x86_64.conf
	source "${MAKEPKG_CONF}"
else
	die "${MAKEPKG_CONF} not found!"
fi

# Source user-specific makepkg.conf overrides
if [[ -r "${XDG_CONFIG_HOME:-$HOME/.config}/pacman/makepkg.conf" ]]; then
	# shellcheck source=/dev/null
	source "${XDG_CONFIG_HOME:-$HOME/.config}/pacman/makepkg.conf"
elif [[ -r "$HOME/.makepkg.conf" ]]; then
	# shellcheck source=/dev/null
	source "$HOME/.makepkg.conf"
fi

if [[ ! -f PKGBUILD ]]; then
	die 'This must be run in the directory of a built package.'
fi

# shellcheck source=contrib/makepkg/PKGBUILD.proto
. ./PKGBUILD
if [[ ${arch[0]} == 'any' ]]; then
	CARCH='any'
fi

STARTDIR=$(pwd)
(( RMDIR )) && trap 'rm -rf $TEMPDIR' EXIT INT TERM QUIT
TEMPDIR=$(mktemp -d --tmpdir checkpkg-script.XXXX)

for _pkgname in "${pkgname[@]}"; do
	comparepkg=$_pkgname
	pkgurl=
	target_pkgver=$(get_full_version "$_pkgname")
	if ! pkgfile=$(find_cached_package "$_pkgname" "$target_pkgver" "$CARCH"); then
		die 'tarball not found for package: %s' "${_pkgname}-$target_pkgver"
	fi

	ln -s "$pkgfile" "$TEMPDIR"

	if (( $# )); then
		case $1 in
			*://*)
				pkgurl=$1 ;;
			/*|*/*)
				pkgurl=$(readlink -m "$1") ;;
			*.pkg.tar*)
				pkgurl=$1 ;;
			'')
				;;
			*)
				comparepkg=$1 ;;
		esac
		shift
	fi
	[[ -n $pkgurl ]] || pkgurl=$(pacman -Spdd --print-format '%l' --noconfirm "$comparepkg") ||
		die "Couldn't download previous package for %s." "$comparepkg"

	oldpkg=${pkgurl##*/}

	if [[ ${oldpkg} = "${pkgfile##*/}" ]]; then
		die "The built package (%s) is the one in the repo right now!" "$_pkgname"
	fi

	if [[ $pkgurl = file://* || ( $pkgurl = /* && -f $pkgurl ) ]]; then
		ln -s "${pkgurl#file://}" "$TEMPDIR/$oldpkg"
	elif [[ -f "$PKGDEST/$oldpkg" ]]; then
		ln -s "$PKGDEST/$oldpkg" "$TEMPDIR/$oldpkg"
	elif [[ -f "$STARTDIR/$oldpkg" ]]; then
		ln -s "$STARTDIR/$oldpkg" "$TEMPDIR/$oldpkg"
	else
		curl -fsLC - --retry 3 --retry-delay 3 -o "$TEMPDIR/$oldpkg" "$pkgurl"
	fi

	bsdtar tf "$TEMPDIR/$oldpkg" | sort > "$TEMPDIR/filelist-$_pkgname-old"
	bsdtar tf "$pkgfile" | sort > "$TEMPDIR/filelist-$_pkgname"

	sdiff -s "$TEMPDIR/filelist-$_pkgname-old" "$TEMPDIR/filelist-$_pkgname"

	find-libprovides "$TEMPDIR/$oldpkg" 2>/dev/null | sort > "$TEMPDIR/libraries-$_pkgname-old"
	find-libprovides "$pkgfile" 2>/dev/null | sort > "$TEMPDIR/libraries-$_pkgname"
	if ! diff_output="$(sdiff -s "$TEMPDIR/libraries-$_pkgname-old" "$TEMPDIR/libraries-$_pkgname")"; then
		message="Sonames differ in $_pkgname!"
		(( WARN )) && warning "$message" || msg "$message"
		echo "$diff_output"
	else
		msg "No soname differences for %s." "$_pkgname"
	fi
done

(( RMDIR )) || msg "Files saved to %s" "$TEMPDIR"
