#!/bin/bash
# Copyright 1999-2004 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: /var/cvsroot/gentoo-x86/x11-base/opengl-update/files/opengl-update-3.0.0,v 1.4 2005/08/17 21:51:02 eradicator Exp $
# Author:  Martin Schlemmer <azarah@gentoo.org>
# Further modifications by Donnie Berkholz <spyderous@gentoo.org>
# Further modifications based off submissions to bug #54984 <cyfred@gentoo.org>
# Further modifications by Jeremy Huddleston <eradicator@gentoo.org>

. /etc/init.d/functions.sh

hasq() {
	local x

	local me=${1}
	shift
        
	for x in "${@}"; do
		if [[ "${x}" == "${me}" ]]; then
			return 0
		fi
	done
	return 1
}

print_usage() {
	cat << FOO
Usage: ${0##*/} [<options>] <GL implementation>
       Set the opengl implementation.
       Valid options:
       --use-old:          If an implementation is already set, use that one.
       --prefix=<val>:     Set the source prefix (default: /usr)
       --dst-prefix=<val>: Set the destination prefix (default: /usr)
       --impl-headers:     Use headers provided by this implementation to
                           override golbal ones provided by opengl-update.

Usage: ${0##*/} --get-implementation
       Print the current implementaion

Notes:
       --impl-headers was default in <opengl-update-2.2.

Examples:
       ${0##*/} xorg-x11
       This will setup things to use libGL.so from X.org.

       ${0##*/} nvidia
       This will setup things to use libGL.so from the nVidia drivers.

WARNING: opengl-update is deprecated and is just a frontend to the opengl
         eselect module.  In the future, opengl-update will be removed
         from portage.  Please see 'eselect opengl help'

FOO
}

get_implementations() {
	local implems
	for dir in ${PREFIX}/lib{,32,64}/opengl/*; do 
		if [[ -d "${dir}" && ${dir##*/} != "global" ]] && ! hasq ${dir##*/} ${implems}; then
			implems=${implems:+${implems} }${dir##*/}
		fi
	done
	echo ${implems}
}

parse_options() {
	local opt
	while [[ ${#} -gt 0 ]]; do
		opt=${1}
		shift
		case ${opt} in
			--use-old)
				if [[ -n "${ACTION}" ]]; then
					ACTION="error"
					eerror "Invalid usage."
				else
					if [[ -n "${CURRENT_GL_IMPLEM}" ]] && hasq ${CURRENT_GL_IMPLEM} ${AVAIL_IMPLEMS}; then
						ACTION="old-implementation"
					fi
				fi				
			;;
			--get-implementation)
				if [[ -n "${ACTION}" ]]; then
					ACTION="error"
					eerror "Invalid usage."
				else
					ACTION="get-implementation"
				fi				
			;;
			--prefix=*)
				PREFIX=${opt#*=}
				AVAIL_IMPLEMS=$(get_implementations)
			;;
			--dst-prefix=*)
				DST_PREFIX=${opt#*=}
			;;
			--impl-headers)
				USE_PROFILE_HEADERS="yes"
			;;
			--help|-h|-?)
				ACION="usage"
			;;
			*)
				if hasq ${opt} ${AVAIL_IMPLEMS}; then
					if [[ "${ACTION}" != "old-implementation" ]]; then
						if [[ -n "${ACTION}" ]]; then
							ACTION="error"
							eerror "Invalid usage."
						else
							ACTION="set-implementation"
							NEW_GL_IMPLEM="${opt}"
						fi
					fi				
				else
					eerror "Unrecognized option: ${opt}"
					ACTION="error"
				fi
			;;
		esac
	done
}

## START PROGRAM ##

NEW_GL_IMPLEM=""
ACTION=""
PREFIX="/usr"
DST_PREFIX="/usr"
AVAIL_IMPLEMS=$(get_implementations)
CURRENT_GL_IMPLEM=$(eselect opengl show)
USE_PROFILE_HEADERS="no"

parse_options ${@}

case ${ACTION} in
	get-implementation)
		eselect opengl show
	;;
	old-implementation)
		ewarn "opengl-update is deprecated and is just a frontend to the opengl"
		ewarn "eselect module.  In the future, opengl-update will be removed"
		ewarn "from portage.  Please see 'eselect opengl help'"

		eselect opengl set --use-old
		exit $?
	;;
	set-implementation)
		ewarn "opengl-update is deprecated and is just a frontend to the opengl"
		ewarn "eselect module.  In the future, opengl-update will be removed"
		ewarn "from portage.  Please see 'eselect opengl help'"

		if [[ ${USE_PROFILE_HEADERS} == "yes" ]] ; then
			eselect opengl set ${NEW_GL_IMPLEM} --prefix="${PREFIX}" --dst-prefix="${DST_PREFIX}" --impl-headers
		else
			eselect opengl set ${NEW_GL_IMPLEM} --prefix="${PREFIX}" --dst-prefix="${DST_PREFIX}"
		fi
	;;
	usage)
		print_usage
		exit 0
	;;
	*)
		print_usage
		exit 1
	;;
esac