#!/usr/bin/env bash

# Host dependency bootstrap shared by install.sh and release validation.

ptlinux_dependency_family()
{
	local distribution_id="${1,,}"
	local distribution_like=" ${2,,} "

	case "$distribution_id" in
		ubuntu|debian|linuxmint|pop|elementary|zorin)
			printf '%s\n' "debian"
			return 0
			;;
		fedora|nobara)
			printf '%s\n' "fedora"
			return 0
			;;
		arch|cachyos|endeavouros|garuda|manjaro)
			printf '%s\n' "arch"
			return 0
			;;
		opensuse-tumbleweed|opensuse-leap|opensuse|suse)
			printf '%s\n' "suse"
			return 0
			;;
	esac

	case "$distribution_like" in
		*" debian "*|*" ubuntu "*)
			printf '%s\n' "debian"
			;;
		*" fedora "*)
			printf '%s\n' "fedora"
			;;
		*" arch "*)
			printf '%s\n' "arch"
			;;
		*" suse "*)
			printf '%s\n' "suse"
			;;
		*)
			printf '%s\n' "unknown"
			;;
	esac
}

ptlinux_resolve_dependency_packages()
{
	local family="$1"
	shift
	local dependency
	local package
	local -a candidates=()
	local -a packages=()

	for dependency in "$@"
	do
		candidates=()
		case "${family}:${dependency}" in
			debian:python)
				candidates=(python3)
				;;
			debian:python-tk)
				candidates=(python3-tk)
				;;
			debian:wine)
				candidates=(wine wine64 wine32:i386)
				;;
			debian:winetricks)
				candidates=(winetricks)
				;;
			debian:gamescope)
				candidates=(gamescope)
				;;
			debian:cabextract)
				candidates=(cabextract)
				;;
			debian:openssl)
				candidates=(openssl)
				;;
			debian:bubblewrap)
				candidates=(bubblewrap)
				;;
			debian:apparmor)
				candidates=(apparmor)
				;;
			fedora:python)
				candidates=(python3)
				;;
			fedora:python-tk)
				candidates=(python3-tkinter)
				;;
			fedora:wine)
				candidates=(wine)
				;;
			fedora:winetricks)
				candidates=(winetricks)
				;;
			fedora:gamescope)
				candidates=(gamescope)
				;;
			fedora:cabextract)
				candidates=(cabextract)
				;;
			fedora:openssl)
				candidates=(openssl)
				;;
			fedora:bubblewrap)
				candidates=(bubblewrap)
				;;
			arch:python)
				candidates=(python)
				;;
			arch:python-tk)
				candidates=(tk)
				;;
			arch:wine)
				candidates=(wine)
				;;
			arch:winetricks)
				candidates=(winetricks)
				;;
			arch:gamescope)
				candidates=(gamescope)
				;;
			arch:cabextract)
				candidates=(cabextract)
				;;
			arch:openssl)
				candidates=(openssl)
				;;
			arch:bubblewrap)
				candidates=(bubblewrap)
				;;
			arch:umu)
				candidates=(umu-launcher)
				;;
			suse:python)
				candidates=(python3)
				;;
			suse:python-tk)
				candidates=(python3-tk)
				;;
			suse:wine)
				candidates=(wine)
				;;
			suse:winetricks)
				candidates=(winetricks)
				;;
			suse:gamescope)
				candidates=(gamescope)
				;;
			suse:cabextract)
				candidates=(cabextract)
				;;
			suse:openssl)
				candidates=(openssl)
				;;
			suse:bubblewrap)
				candidates=(bubblewrap)
				;;
			*)
				printf 'No package mapping for %s on %s systems.\n' "$dependency" "$family" >&2
				return 1
				;;
		esac

		for package in "${candidates[@]}"
		do
			if [[ " ${packages[*]} " != *" ${package} "* ]]
			then
				packages+=("$package")
			fi
		done
	done

	printf '%s\n' "${packages[*]}"
}

ptlinux_read_distribution()
{
	local release_file="${PTLINUX_OS_RELEASE:-/etc/os-release}"
	local key
	local value
	PTLINUX_DISTRIBUTION_ID="unknown"
	PTLINUX_DISTRIBUTION_LIKE=""

	if [[ ! -r "$release_file" ]]
	then
		return 0
	fi

	while IFS='=' read -r key value
	do
		value="${value%\"}"
		value="${value#\"}"
		value="${value%\'}"
		value="${value#\'}"
		case "$key" in
			ID)
				PTLINUX_DISTRIBUTION_ID="$value"
				;;
			ID_LIKE)
				PTLINUX_DISTRIBUTION_LIKE="$value"
				;;
		esac
	done < "$release_file"
}

ptlinux_has_wine_stack()
{
	local wine_root
	if command -v wine >/dev/null 2>&1 && command -v wineboot >/dev/null 2>&1
	then
		return 0
	fi
	for wine_root in /opt/wine-stable/bin /opt/wine-staging/bin /opt/wine-devel/bin
	do
		if [[ -x "${wine_root}/wine" && -x "${wine_root}/wineboot" ]]
		then
			return 0
		fi
	done
	return 1
}

ptlinux_detect_missing_dependencies()
{
	local python_bin="${PYTHON_BIN:-python3}"
	local family="${1:-}"
	PTLINUX_MISSING_DEPENDENCIES=()

	if ! command -v "$python_bin" >/dev/null 2>&1
	then
		PTLINUX_MISSING_DEPENDENCIES+=(python python-tk)
	elif ! "$python_bin" -c 'import _tkinter' >/dev/null 2>&1
	then
		PTLINUX_MISSING_DEPENDENCIES+=(python-tk)
	fi
	if ! ptlinux_has_wine_stack
	then
		PTLINUX_MISSING_DEPENDENCIES+=(wine)
	fi
	if ! command -v winetricks >/dev/null 2>&1
	then
		PTLINUX_MISSING_DEPENDENCIES+=(winetricks)
	fi
	if ! command -v cabextract >/dev/null 2>&1
	then
		PTLINUX_MISSING_DEPENDENCIES+=(cabextract)
	fi
	if ! command -v openssl >/dev/null 2>&1
	then
		PTLINUX_MISSING_DEPENDENCIES+=(openssl)
	fi
	if [[ ! -x /usr/bin/bwrap ]]
	then
		PTLINUX_MISSING_DEPENDENCIES+=(bubblewrap)
	fi
	if [[ "$family" == "debian" \
		&& ( "${PTLINUX_DISTRIBUTION_ID,,}" == "ubuntu" \
			|| " ${PTLINUX_DISTRIBUTION_LIKE,,} " == *" ubuntu "* ) \
		&& -e /proc/sys/kernel/apparmor_restrict_unprivileged_userns \
		&& ! -x /usr/sbin/apparmor_parser ]]
	then
		PTLINUX_MISSING_DEPENDENCIES+=(apparmor)
	fi
	if [[ "$family" == "arch" ]] && ! command -v umu-run >/dev/null 2>&1
	then
		PTLINUX_MISSING_DEPENDENCIES+=(umu)
	fi
}

ptlinux_select_privilege_command()
{
	PTLINUX_PRIVILEGE_COMMAND=()
	if (( EUID == 0 ))
	then
		return 0
	fi
	if command -v sudo >/dev/null 2>&1
	then
		PTLINUX_PRIVILEGE_COMMAND=(sudo)
		return 0
	fi
	if command -v doas >/dev/null 2>&1
	then
		PTLINUX_PRIVILEGE_COMMAND=(doas)
		return 0
	fi
	if command -v pkexec >/dev/null 2>&1
	then
		PTLINUX_PRIVILEGE_COMMAND=(pkexec)
		return 0
	fi
	printf '%s\n' "Root access is required, but sudo, doas, and pkexec are unavailable." >&2
	return 1
}

ptlinux_print_command()
{
	printf '%s' "  +"
	printf ' %q' "$@"
	printf '\n'
}

ptlinux_run_as_root()
{
	ptlinux_print_command "${PTLINUX_PRIVILEGE_COMMAND[@]}" "$@"
	"${PTLINUX_PRIVILEGE_COMMAND[@]}" "$@"
}

ptlinux_install_resolved_packages()
{
	local family="$1"
	shift
	local -a packages=("$@")
	local architecture
	local has_i386=0
	local package

	ptlinux_select_privilege_command
	case "$family" in
		debian)
			for package in "${packages[@]}"
			do
				if [[ "$package" == "wine32:i386" ]]
				then
					has_i386=1
				fi
			done
			if (( has_i386 == 1 ))
			then
				while IFS= read -r architecture
				do
					if [[ "$architecture" == "i386" ]]
					then
						has_i386=2
					fi
				done < <(dpkg --print-foreign-architectures)
				if (( has_i386 == 1 ))
				then
					ptlinux_run_as_root dpkg --add-architecture i386
				fi
			fi
			ptlinux_run_as_root apt-get update
			ptlinux_run_as_root apt-get install -y "${packages[@]}"
			;;
		fedora)
			if command -v dnf5 >/dev/null 2>&1
			then
				ptlinux_run_as_root dnf5 install -y "${packages[@]}"
			else
				ptlinux_run_as_root dnf install -y "${packages[@]}"
			fi
			;;
		arch)
			ptlinux_run_as_root pacman -S --needed --noconfirm "${packages[@]}"
			;;
		suse)
			ptlinux_run_as_root zypper --non-interactive install "${packages[@]}"
			;;
		*)
			printf 'Unsupported dependency family: %s\n' "$family" >&2
			return 1
			;;
	esac
}

ptlinux_install_host_dependencies()
{
	local dry_run="$1"
	local family
	local package_line
	local -a packages=()

	ptlinux_read_distribution
	family="$(ptlinux_dependency_family "$PTLINUX_DISTRIBUTION_ID" "$PTLINUX_DISTRIBUTION_LIKE")"
	ptlinux_detect_missing_dependencies "$family"
	if (( ${#PTLINUX_MISSING_DEPENDENCIES[@]} == 0 ))
	then
		printf '%s\n' "All required host dependencies are already available."
		return 0
	fi
	if [[ "$family" == "unknown" ]]
	then
		printf 'Unsupported distribution: %s. Re-run with --skip-deps after installing: %s\n' \
			"$PTLINUX_DISTRIBUTION_ID" "${PTLINUX_MISSING_DEPENDENCIES[*]}" >&2
		return 1
	fi
	package_line="$(ptlinux_resolve_dependency_packages \
		"$family" "${PTLINUX_MISSING_DEPENDENCIES[@]}")"
	read -r -a packages <<< "$package_line"

	printf 'Missing host components: %s\n' "${PTLINUX_MISSING_DEPENDENCIES[*]}"
	printf 'Distribution packages: %s\n' "${packages[*]}"
	if (( dry_run == 1 ))
	then
		printf '%s\n' "Dry run: system packages were not changed."
		return 0
	fi

	printf '%s\n' "Installing missing host dependencies (authentication may be requested)."
	ptlinux_install_resolved_packages "$family" "${packages[@]}"
	hash -r
	ptlinux_detect_missing_dependencies "$family"
	if (( ${#PTLINUX_MISSING_DEPENDENCIES[@]} != 0 ))
	then
		printf 'Dependencies remain unavailable after package installation: %s\n' \
			"${PTLINUX_MISSING_DEPENDENCIES[*]}" >&2
		return 1
	fi
	printf '%s\n' "Host dependency installation completed."
}

ptlinux_dependency_main()
{
	if [[ "${1:-}" != "--resolve" || $# -lt 3 ]]
	then
		printf '%s\n' "Usage: install-dependencies.sh --resolve DISTRO DEPENDENCY..." >&2
		return 2
	fi
	shift
	local distribution_id="$1"
	shift
	local family
	family="$(ptlinux_dependency_family "$distribution_id" "")"
	if [[ "$family" == "unknown" ]]
	then
		printf 'Unsupported distribution: %s\n' "$distribution_id" >&2
		return 1
	fi
	ptlinux_resolve_dependency_packages "$family" "$@"
}

if [[ "${BASH_SOURCE[0]}" == "$0" ]]
then
	set -euo pipefail
	ptlinux_dependency_main "$@"
fi