# Copyright 1999-2005 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2
# $Id: $

DESCRIPTION="Manage /bin/sh implementations"
MAINTAINER="pioto@gentoo.org"
SVN_DATE='$Date: $'
VERSION=$(svn_date_to_version "${SVN_DATE}" )

## Functions ##

# find a list of vi symlink targets, best first
find_targets() {
	local f
	for f in \
			"${ROOT}"/bin/bash \
			"${ROOT}"/bin/busybox \
			"${ROOT}"/bin/dash \
			"${ROOT}"/bin/zsh \
		; do
		if [[ -f "${f}" ]] ; then
			echo $(basename "${f}" )
		fi
	done
}

# try to remove the sh symlink
remove_symlinks() {
	rm -f "${ROOT}"/bin/sh &>/dev/null
}


# set the sh symlink
set_symlinks() {
	local target="${1}" targets
	if is_number "${target}" && [[ ${target} -ge 1 ]] ; then
		targets=( $(find_targets ) )
		target=${targets[$(( ${target} - 1 ))]}
	fi

	#local dir
	#if [[ ${target} == "busybox" ]]; then
	#	dir="${ROOT}/bin"
	#else
	#	dir="${ROOT}/usr/bin"
	#fi

	if [[ -f "${ROOT}/bin/${target}" ]] ; then
		remove_symlinks

		ln -s "${ROOT}/bin/${target}" "${ROOT}/bin/sh" || \
			die "Couldn't set ${target} /bin/sh symlink"
	else
		die -q  "Target \"${1}\" doesn't appear to be valid!"
	fi
}

### show action ###

describe_show() {
	echo "Show the current sh implementation"
}

do_show() {
	[[ -z "${@}" ]] || die -q "Too many parameters"

	write_list_start "Current sh implementation:"
	if [[ -L "${ROOT}/bin/sh" ]] ; then
		write_kv_list_entry "$(basename $(canonicalise ${ROOT}/bin/sh ) )" ""
	elif [[ -e "${ROOT}/bin/sh" ]] ; then
		write_kv_list_entry "(not a symlink)" ""
	else
		write_kv_list_entry "(unset)" ""
	fi
}

### list action ###

describe_list() {
	echo "List available sh implementations"
}

do_list() {
	[[ -z "${@}" ]] || die -q "Too many parameters"

	local i targets
	targets=( $(find_targets ) )
	if [[ -n ${targets[@]} ]] ; then
		for (( i = 0 ; i < ${#targets[@]} ; i = i + 1 )) ; do
			[[ ${targets[${i}]} == $(basename $(canonicalise ${ROOT}/bin/sh ) ) ]] && \
				targets[${i}]="${targets[${i}]} $(highlight '*' )"
		done
		write_list_start "Available sh implementations:"
		write_numbered_list "${targets[@]}"
	else
		write_kv_list_entry "(none found)" ""
	fi
}

### set action ###

describe_set() {
	echo "Set a new sh implementation provider"
}

describe_set_options() {
	echo "target : Target name or number (from 'list' action)"
}

describe_set_parameters() {
	echo "<target>"
}

do_set() {
	if [[ -z "${1}" ]] ; then
		die -q "You didn't give me a provider name"

	elif [[ -n "${2}" ]] ; then
		die -q "Too many parameters"

	elif [[ -L "${ROOT}/usr/bin/vi" ]] ; then
		if ! remove_symlinks ; then
			die -q "Can't remove existing provider"
		elif ! set_symlinks "${1}" ; then
			die -q "Can't set new provider"
		fi

	elif [[ -e "${ROOT}/bin/sh" ]] ; then
		die -q "Sorry, ${ROOT}/bin/sh confuses me"

	else
		set_symlinks "${1}" || die -q "Can't set a new provider"
	fi
}

### update action ###

describe_update() {
	echo "Automatically update the sh provider"
}

describe_update_options() {
	echo "--if-unset : Do not override existing implementation"
}

do_update() {
	[[ -z "${1}" ]] || ( [[ -z "${2}" ]] && [[ "${1}" == "--if-unset" ]] ) || \
		die -q "Usage error"

	if [[ -L "${ROOT}/bin/sh" ]] ; then
		[[ ${1} == "--if-unset" ]] && return
		remove_symlinks || die -q "Can't remove existing link"
	fi
	if [[ -e "${ROOT}/bin/sh" ]] ; then
		die -q "Can't set a new provider"
	elif ! [[ -z $(find_targets ) ]] ; then
		set_symlinks 1 || die -q "Can't set a new provider"
	fi
}

# vim: set ft=eselect :