# -*-eselect-*-  vim: ft=eselect
# Copyright 1999-2016 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

DESCRIPTION="Manage the XvMC implementation used by your system"
MAINTAINER="{cardoe,junghans}@gentoo.org"
VERSION="0.4"

init_XVMC_vars() {
	get_libname() {
		case ${OSTYPE} in
			darwin*) echo ${1:+.}${1}.dylib ;;
			*) echo .so${1:+.}${1} ;;
		esac
	}

	XVMCLIBS=(
		"libXvMCNVIDIA_dynamic$(get_libname 1)"
		"libXvMC$(get_libname 1)"
		"libviaXvMC$(get_libname 1)"
		"libviaXvMCPro$(get_libname 1)"
		"libchromeXvMC$(get_libname 1)"
		"libchromeXvMCPro$(get_libname 1)"
		"libXvMCVIA$(get_libname)"
		"libXvMCVIAPro$(get_libname)"
		"libI810XvMC$(get_libname 1)"
		"/usr/lib/libIntelXvMC$(get_libname)"
		"libAMDXvBA$(get_libname 1)"
	)

	XVMCPRETTY=(
		"nvidia"
		"xorg-x11"
		"via"
		"via-pro"
		"openchrome"
		"openchrome-pro"
		"unichrome"
		"unichrome-pro"
		"intel-i810"
		"intel-i915/i965"
		"ati"
	)
}

get_implementation_indices() {
	local ret n
	for (( n = 0; n < ${#XVMCLIBS[@]}; ++n )); do
		[[ -e "${EROOT}/usr/lib/${XVMCLIBS[n]##*/}" ]] && ret+=($n)
	done

	echo ${ret[@]}
}

get_current_implementation_index() {
	local n
	if [[ -f "${EROOT}/etc/X11/XvMCConfig" ]]; then
		local current=$(< "${EROOT}/etc/X11/XvMCConfig")
		for (( n = 0; n < ${#XVMCLIBS[@]}; ++n )); do
			if [[ "${XVMCLIBS[n]}" = "${current}" ]]; then
				echo "${n}"
				return
			fi
		done
	fi

	echo "-1"
}

set_new_implementation() {
	echo -n "Switching to ${XVMCPRETTY[$1]} XvMC implementation..."
	touch "${EROOT}/etc/X11/XvMCConfig" 2>&1 > /dev/null
	if [[ $? -eq 0 ]]; then
		echo "${XVMCLIBS[$1]}" > "${EROOT}/etc/X11/XvMCConfig"
		chmod 644 "${EROOT}/etc/X11/XvMCConfig"
		[[ ${EROOT} == "/" ]] && chown 0:0 "${EROOT}/etc/X11/XvMCConfig"
		echo " done"
	else
		echo " failed!"
		echo "Insufficient privileges"
	fi
}

### list action

## {{{ list stuff
describe_list() {
	echo "List Available XvMC implementations"
}

do_list() {
	local output n
	init_XVMC_vars
	local avail=( $(get_implementation_indices) )
	local current=$(get_current_implementation_index)
	write_list_start \
		"Available XvMC implementations ($(highlight '*') is current):"

	for n in "${avail[@]}"; do
		output[n]=${XVMCPRETTY[n]}
		[[ ${current} -eq ${n} ]] \
			&& output[n]=$(highlight_marker "${output[n]}")
	done
	write_numbered_list -m "(none found)" "${output[@]}"

	return 0
}
## }}}

### show action

## {{{ show stuff
describe_show() {
	echo "Print the current XvMC implementation."
}

do_show() {
	init_XVMC_vars
	local current=$(get_current_implementation_index)
	write_list_start "Current XvMC implementation:"

	if [[ ${current} -ne -1 ]]; then
		echo "${XVMCPRETTY[current]}"
		return 0
	else
		echo "(none)"
		return 2
	fi
}
## }}}

### set action

## {{{ set stuff
describe_set() {
	echo "Select the XvMC implementation"
}

describe_set_parameters() {
	echo "<target>"
}

describe_set_options() {
	echo "<target> : XvMC implementation to activate"
	echo "--use-old : If an implementation is already set, use that one instead"
}

do_set() {
	init_XVMC_vars
	local current=$(get_current_implementation_index)
	local avail=( $(get_implementation_indices) )
	local n new action

	while [[ ${#@} -gt 0 ]]; do
		local opt=${1}
		shift
		case ${opt} in
			--use-old)
				if [[ ${current} -gt -1 ]]; then
					(( ${current} < ${#XVMCPRETTY[@]} )) && action="old-implementation"
				fi
				;;
			*)
				[[ -z ${action} ]] && action="set-implementation"

				if is_number ${opt} ; then
					new=${avail[opt - 1]}
					if [[ -z ${new} ]]; then
						die -q "Unrecognized option: ${opt}"
					fi
				elif has ${opt} ${XVMCPRETTY[@]}; then
					for (( n = 0; n < ${#XVMCPRETTY[@]}; ++n )); do
						[[ "${XVMCPRETTY[n]}" = "${opt}" ]] && new=${n}
					done
				else
					die -q "Unrecognized option: ${opt}"
				fi
				;;
		esac
	done

	case ${action} in
		old-implementation)
			set_new_implementation ${current}
			return $?
		;;
		set-implementation)
			if [[ -n ${new} ]]; then
				set_new_implementation ${new}
				return $?
			else
				die -q "Please specify an implementation to set"
			fi
		;;
		*)
			die -q "Invalid usage of set action."
	esac
}