#!/bin/bash

#
#  Singe 3
#  Copyright (C) 2006-2026 Scott Duensing <scott@kangaroopunch.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public Licens
# as published by the Free Software Foundation; either version 3
# 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., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA.
#

# Builds Singe and every vendored library for one platform, or all of them.  The work is done
# by the CMake superbuild (cmake/Superbuild.cmake, one preset per platform in
# CMakePresets.json); this script installs the host packages and calls it:
#
#     ./build-all.sh              every supported platform
#     ./build-all.sh linux x86_64 one platform
#
# Anything cmake --build accepts can follow the platform, so a single library can be redone:
#
#     ./build-all.sh linux x86_64 --target rebuild-ffmpeg

G_BUILDDIR=.builddir
G_INSTALL="$(dirname "$0")/INSTALL"

# The one copy of the host package list.  Everything else that names these packages derives from it.
# Grouped by what wants them, because the SDL3 half is long and a bare list gives no clue why a
# package is here:  SDL3 compiles a backend whenever it finds the headers, so a package missing from
# this list does not fail the build, it quietly drops a backend from the binary.
G_HOSTPACKAGES=(
	# Toolchain
	build-essential
	cmake
	git-lfs
	pkg-config
	perl
	nasm
	llvm
	autoconf
	automake
	libtool
	# Content the build generates:  embedded images, the menu video, the LuaSec table, the manual
	imagemagick
	ffmpeg
	lua5.4
	asciidoctor
	ruby-asciidoctor-pdf
	# Video decode and display
	libva-dev
	libvdpau-dev
	libdrm-dev
	libgl-dev
	libegl-dev
	libgles-dev
	libgbm-dev
	# SDL3 audio backends
	libasound2-dev
	libpulse-dev
	libpipewire-0.3-dev
	libjack-jackd2-dev
	libsndio-dev
	# SDL3 device hotplug, desktop integration and input methods
	libudev-dev
	libdbus-1-dev
	libibus-1.0-dev
	libxkbcommon-dev
	# SDL3 X11 video backend and the extensions it uses
	libx11-dev
	libxext-dev
	libxfixes-dev
	libxi-dev
	libxcursor-dev
	libxrandr-dev
	libxss-dev
	libxtst-dev
	# SDL3 Wayland video backend
	libwayland-dev
	wayland-protocols
	libdecor-0-dev
)

G_INSTALLLEAD="Host packages (what build-all.sh installs):"
G_INSTALLWIDTH=72


function buildAll() {
	local OS=$1
	local ARCH=$2
	shift 2

	# Every platform builds with the zig the build fetches itself; the Pi preset also fetches its
	# platform packages and macOS needs the Apple SDK tarball (see INSTALL).
	# "macos universal" builds both macOS presets and joins them with llvm-lipo.
	if [[ "${OS}" == "macos" && "${ARCH}" == "universal" ]]; then
		buildAll macos aarch64 "$@"
		buildAll macos x86_64 "$@"
		cmake -P cmake/zig/macosUniversal.cmake
		return
	fi

	cmake --preset ${OS}-${ARCH}
	cmake --build --preset ${OS}-${ARCH} "$@"
}


# assets/ holds the artwork, the font and the menu video in Git LFS.  A clone made without git-lfs
# leaves pointer stubs -- a hundred and thirty bytes of text where a video should be -- and the
# resource generators embed them without complaining, so the failure only shows up at run time as a
# menu with no background.  One sentinel is enough to tell the two apart.
function checkoutHydrated() {
	local SENTINEL="$(dirname "$0")/assets/180503_01_PurpleGrid.mp4"

	# A sentinel that is not there at all is not a hydrated checkout either, and saying so beats
	# passing quietly because the path was wrong.
	[[ -f "${SENTINEL}" ]] || return 1
	! head -c 64 "${SENTINEL}" | grep -q "git-lfs.github.com/spec"
}


# The package list as INSTALL wants to read it:  one sentence, wrapped, ending in a full stop.
function installParagraph() {
	local LINE="${G_INSTALLLEAD}"
	local SEP="  "
	local WORD

	for WORD in "${G_HOSTPACKAGES[@]}"; do
		if (( ${#LINE} + ${#SEP} + ${#WORD} > G_INSTALLWIDTH )); then
			printf '%s\n' "${LINE}"
			LINE="${WORD}"
		else
			LINE="${LINE}${SEP}${WORD}"
		fi
		SEP=" "
	done
	printf '%s.\n' "${LINE}"
}


# What INSTALL says today:  from the lead line to the first line that ends the sentence.
function installCurrent() {
	awk -v lead="${G_INSTALLLEAD}" '
		index($0, lead) == 1 { found = 1 }
		found { print; if (/\.$/) exit }
	' "${G_INSTALL}"
}


function installMatches() {
	# A checkout without INSTALL is not worth nagging about; there is nothing to disagree with.
	[[ ! -f "${G_INSTALL}" ]] || [[ "$(installParagraph)" == "$(installCurrent)" ]]
}


# Writes the paragraph back into INSTALL, replacing whatever sentence is there now.
function installSync() {
	local TEMP

	TEMP=$(mktemp)
	awk -v lead="${G_INSTALLLEAD}" -v replacement="$(installParagraph)" '
		index($0, lead) == 1 && !done {
			print replacement
			skip = 1
		}
		skip { if (/\.$/) { skip = 0; done = 1 } next }
		{ print }
	' "${G_INSTALL}" > "${TEMP}"
	mv "${TEMP}" "${G_INSTALL}"
}


# -e = stop script on errors
# -u = stop script on undefined variable
# -o pipefail = stop pipeline if any step fails
set -euo pipefail

case "${1:-}" in
	--packages)
		printf '%s\n' "${G_HOSTPACKAGES[@]}"
		exit 0
		;;
	--sync-install)
		installSync
		echo "INSTALL rewritten from build-all.sh."
		exit 0
		;;
esac

mkdir -p ${G_BUILDDIR}


# Host packages the build needs on a Debian based system.  INSTALL prints the same list for a
# reader who has not run anything yet, so it is written from this one:  --sync-install rewrites
# that paragraph and every build checks it, which is why there is no second list to keep in step.
if ! installMatches; then
	echo "warning:  INSTALL's host package list no longer matches this script."
	echo "          Run ./build-all.sh --sync-install to write it from here."
fi
sudo apt-get install -y "${G_HOSTPACKAGES[@]}"


if ! checkoutHydrated; then
	echo "error:  assets/ holds git-lfs pointer files, not the real artwork, font and video."
	echo "        The build would embed those stubs and produce a broken binary."
	echo "        Fix the checkout with:  git lfs install && git lfs pull"
	exit 1
fi


if [[ $# -ge 2 ]]; then
	buildAll "$@" 2>&1 | tee ${G_BUILDDIR}/$1-$2.log
else
	buildAll linux   x86_64  2>&1 | tee ${G_BUILDDIR}/linux-x86_64.log
	buildAll macos   universal 2>&1 | tee ${G_BUILDDIR}/macos-universal.log
	buildAll linux   aarch64 2>&1 | tee ${G_BUILDDIR}/linux-aarch64.log
	buildAll windows x86_64  2>&1 | tee ${G_BUILDDIR}/windows-x86_64.log
fi