#!/bin/bash
# Copyright 1999-2004 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Header: /home/cvsd/magellan-cvs/magellan-src/opengl-update/opengl-update.sh,v 1.10 2007-11-14 19:19:16 niro 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>
#
# hacked for use with magellan-linux
# <niro@magellan-linux.de>
#

hasq()
{
	local x

	local me=$1
	shift

	for x in $@
	do
		[[ ${x} = ${me} ]] && return 0
	done

	return 1
}

check_user()
{
	if [[ $(id -u) -ne 0 ]]
	then
		echo "$0: Must be run as root."
		exit 1
	fi
}

get_current_implem()
{
	local implem

	# jre does always exist!
	if [ -f ${ENV_D_JRE} ]
	then
		source "${ENV_D_JRE}"
		if [[ -n ${JAVA_PROFILE} ]]
		then
			implem="${JAVA_PROFILE}"
		fi
		unset JAVA_PROFILE
	fi

	echo "${implem}"
}

get_implementations()
{
	local implems

	for dir in ${PREFIX}/java/*
	do
		if [ -d ${dir} ] &&
			[[ ${dir##*/} != global ]] &&
			! hasq "${dir##*/}" "${implems}"
		then
			implems="${implems:+${implems} }${dir##*/}"
		fi
	done

	echo "${implems}"
}

print_version()
{
	echo "java-update ${VERSION}"
}

print_usage()
{
	# Get grammar right in message
	local IS_ARE IMPLEM_PLURAL

	if [[ $(echo ${AVAIL_IMPLEMS} | wc -w) -eq 1 ]]
	then
		IS_ARE="is"
		IMPLEM_PLURAL=""
	else
		IS_ARE="are"
		IMPLEM_PLURAL="s"
	fi

	print_version

	cat << FOO
Usage: ${0##*/} [<options>] <Java implementation>
       Set the Java implementation.
       Valid options:
       --help|-h|-?:       Prints this help.
       --version:          Shows the version of this utility.
       --use-old:          If an implementation is already set, use that one.

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

       This utility switches between Java implementations. There ${IS_ARE}
       $(echo ${AVAIL_IMPLEMS} | wc -w) available implementation${IMPLEM_PLURAL}: ${AVAIL_IMPLEMS}

Examples:
       ${0##*/} java6-sun
       This will setup things to use Java Version 6 from Sun.

       ${0##*/} java7-openjdk
       This will setup things to use OpenJDK Version 7.

FOO
	exit 1
}

parse_options()
{
	local opt

	while [[ ${#} -gt 0 ]]
	do
		opt=$1
		shift
		case ${opt} in
			--use-old)
				if [[ -n ${ACTION} ]]
				then
					ACTION="error"
					echo "Invalid usage."
				else
					if [[ -n "${CURRENT_JAVA_IMPLEM}" ]] &&
						hasq "${CURRENT_JAVA_IMPLEM}" "${AVAIL_IMPLEMS}"
					then
						ACTION="old-implementation"
					fi
				fi
				;;

			--get-implementation)
				if [[ -n ${ACTION} ]]
				then
					ACTION="error"
					echo "Invalid usage."
				else
					ACTION="get-implementation"
				fi
				;;

			--help|-h|-?) ACTION="usage" ;;
			--version) ACTION="version" ;;
			*)
				if hasq "${opt}" "${AVAIL_IMPLEMS}"
				then
					if [[ ${ACTION} != old-implementation ]]
					then
						if [[ -n ${ACTION} ]]
						then
							ACTION="error"
							echo "Invalid usage."
						else
							ACTION="set-implementation"
							NEW_JAVA_IMPLEM="${opt}"
						fi
					fi
				else
					echo "Unrecognized option: ${opt}"
					ACTION="error"
				fi
				;;
		esac
	done
}

set_new_implementation()
{
	local JAVA_IMPLEM="$1"
	local JAVA_LOCAL

	check_user

	# Set a sane umask... bug #83115
	umask 022

	if ! hasq "${JAVA_IMPLEM}" "${AVAIL_IMPLEMS}"
	then
		echo "Invalid profile selected."
		exit 1
	fi

	echo "Switching to ${JAVA_IMPLEM} Java interface"

	[ -f ${ENV_D_JRE} ] && rm -f ${ENV_D_JRE}
	[ -f ${ENV_D_JDK} ] && rm -f ${ENV_D_JDK}
	[ -f ${ENV_D_GLOBAL_CLASSPATH} ] && rm -f ${ENV_D_GLOBAL_CLASSPATH}
	[ -f ${ENV_D_EOF_CLASSPATH} ] && rm -f ${ENV_D_EOF_CLASSPATH}

	cat ${PREFIX}/java/${JAVA_IMPLEM}/jre.conf  >> ${ENV_D_JRE}
	echo "JAVA_PROFILE=\"${JAVA_IMPLEM}\"" >> ${ENV_D_JRE}

	# set global classpath
	if [ -f ${PREFIX}/java/${JAVA_IMPLEM}/global-classpath.conf ]
	then
		cat ${PREFIX}/java/${JAVA_IMPLEM}/global-classpath.conf  >> ${ENV_D_GLOBAL_CLASSPATH}
	elif [ -f ${PREFIX}/java/global/global-classpath.conf ]
	then
		cat ${PREFIX}/java/global/global-classpath.conf  >> ${ENV_D_GLOBAL_CLASSPATH}
	else
		echo "Warning: global-classpath.conf is missing!"
	fi

	# set eof classpath
	if [ -f ${PREFIX}/java/${JAVA_IMPLEM}/eof-classpath.conf ]
	then
		cat ${PREFIX}/java/${JAVA_IMPLEM}/eof-classpath.conf  >> ${ENV_D_EOF_CLASSPATH}
	elif [ -f ${PREFIX}/java/global/eof-classpath.conf ]
	then
		cat ${PREFIX}/java/global/eof-classpath.conf  >> ${ENV_D_EOF_CLASSPATH}
	else
		echo "Warning: eof-classpath.conf is missing!"
	fi

	# set jdk too if installed
	if [ -f ${PREFIX}/java/${JAVA_IMPLEM}/jdk.conf ]
	then
		cat ${PREFIX}/java/${JAVA_IMPLEM}/jdk.conf  >> ${ENV_D_JDK}
		echo "JAVA_PROFILE=\"${JAVA_IMPLEM}\"" >> ${ENV_D_JDK}
	fi

	env-rebuild

	return 0
}

## START PROGRAM ##

ENV_D_JRE="/etc/env.d/21java"
ENV_D_JDK="/etc/env.d/22java-jdk"
ENV_D_GLOBAL_CLASSPATH="/etc/env.d/22java-global-classpath"
ENV_D_EOF_CLASSPATH="/etc/env.d/30java-eof-classpath"
NEW_JAVA_IMPLEM=""
ACTION=""
PREFIX="/etc"
AVAIL_IMPLEMS=$(get_implementations)
CURRENT_JAVA_IMPLEM=$(get_current_implem)
VERSION="@@VERSION@@"

parse_options $@

case ${ACTION} in
	get-implementation)
		if [[ -n ${CURRENT_JAVA_IMPLEM} ]]
		then
			echo ${CURRENT_JAVA_IMPLEM}
			retval=0
		else
			retval=2
		fi
		;;

	old-implementation)
		set_new_implementation ${CURRENT_JAVA_IMPLEM}
		retval=$?
		;;

	set-implementation)
		if [[ -n ${NEW_JAVA_IMPLEM} ]]
		then
			set_new_implementation ${NEW_JAVA_IMPLEM}
			retval=$?
		else
			print_usage
			retval=1
		fi
		;;

	version) print_version; retval=0 ;;
	usage) print_usage; retval=0 ;;
	error) print_usage; retval=1 ;;
	*) print_usage; retval=1;;
esac

exit "${retval}"