#!/usr/bin/env bash

set -euo pipefail

export DEBIAN_FRONTEND=noninteractive
if [[ -f /etc/apt/sources.list.d/ubuntu.sources ]]
then
	sed -i 's/^Types: deb$/Types: deb deb-src/' \
		/etc/apt/sources.list.d/ubuntu.sources
fi
apt-get update
apt-get install --yes build-essential ca-certificates devscripts dpkg-dev patch xz-utils
apt-get build-dep --yes gamescope

BUILD_ROOT="$(mktemp -d /tmp/ptlinux-gamescope.XXXXXX)"
trap 'rm -rf -- "$BUILD_ROOT"' EXIT
tar --extract \
	--file /sources/gamescope_3.16.20+ds.orig.tar.xz \
	--directory "$BUILD_ROOT"
SOURCE_ROOT="$(find "$BUILD_ROOT" -mindepth 1 -maxdepth 1 -type d -print -quit)"
if [[ -z "$SOURCE_ROOT" ]]
then
	printf '%s\n' "The Gamescope source archive has no top-level directory." >&2
	exit 1
fi
tar --extract \
	--file /sources/gamescope_3.16.20+ds-1.debian.tar.xz \
	--directory "$SOURCE_ROOT"

PATCH_ROOT="/workspace/native/gamescope/patches"
PATCH_SERIES=(
	gamescope-wayland-letterbox-backing.patch
	gamescope-wayland-libdecor-input-scope.patch
	gamescope-lazy-output-images.patch
	gamescope-wayland-live-resize.patch
	gamescope-keep-nested-windows-visible.patch
)
mkdir -p -- "${SOURCE_ROOT}/debian/patches"
touch "${SOURCE_ROOT}/debian/patches/series"
for patch_name in "${PATCH_SERIES[@]}"
do
	install -m 0644 \
		"${PATCH_ROOT}/${patch_name}" \
		"${SOURCE_ROOT}/debian/patches/${patch_name}"
	if ! grep -Fqx -- "$patch_name" "${SOURCE_ROOT}/debian/patches/series"
	then
		printf '%s\n' "$patch_name" >> "${SOURCE_ROOT}/debian/patches/series"
	fi
done

(
	cd "$SOURCE_ROOT"
	DEB_BUILD_OPTIONS=nocheck dpkg-buildpackage --build=binary --no-sign -jauto
)
PACKAGE="$(find "$BUILD_ROOT" -maxdepth 1 -type f \
	-name 'gamescope_*_amd64.deb' -print -quit)"
if [[ -z "$PACKAGE" ]]
then
	printf '%s\n' "The Gamescope build did not produce an amd64 Debian package." >&2
	exit 1
fi
EXTRACT_ROOT="${BUILD_ROOT}/package"
dpkg-deb --extract "$PACKAGE" "$EXTRACT_ROOT"
if [[ -x "${EXTRACT_ROOT}/usr/games/gamescope" ]]
then
	BINARY="${EXTRACT_ROOT}/usr/games/gamescope"
elif [[ -x "${EXTRACT_ROOT}/usr/bin/gamescope" ]]
then
	BINARY="${EXTRACT_ROOT}/usr/bin/gamescope"
else
	printf '%s\n' "The Gamescope Debian package contains no executable." >&2
	exit 1
fi
install -m 0755 "$BINARY" \
	/output/gamescope-3.16.20-ubuntu26.04-amd64
chown "${HOST_UID}:${HOST_GID}" \
	/output/gamescope-3.16.20-ubuntu26.04-amd64