# -*-eselect-*-  vim: ft=eselect
# Copyright 1999-2017 Gentoo Foundation
# Distributed under the terms of the GNU General Public License v2

DESCRIPTION="Manages the /etc/herbstluftwm/theme symlink"
MAINTAINER="overlay@genthree.io"
VERSION="1.0.0"

# find all installed themes
find_targets() {
	find "${EROOT}"/usr/share/herbstluftwm/themes -mindepth 1 -maxdepth 1 \( -type f -o -type l \) -executable -printf '%P\n'
}

# try to remove the theme symlink
remove_symlink() {
	rm "${EROOT}"/etc/herbstluftwm/theme &>/dev/null
}

# set the theme symlink
set_symlink() {
	local target="${1}"

	if is_number "${target}" && [[ ${target} -ge 1 ]] ; then
		local targets=( $(find_targets) )
		target=${targets[target-1]}
	fi

	if [[ -z ${target} ]]; then
		die -q "Target '$1' doesn't appear to be valid!"
	elif [[ -x ${EROOT}/usr/share/herbstluftwm/themes/${target} ]]; then
		ln -s "/usr/share/herbstluftwm/themes/${target}" "${EROOT}/etc/herbstluftwm/theme"
	else
		die -q "Target '$1' doesn't appear to be valid!"
	fi
}

### show action ###

describe_show() {
	echo "Show the current herbstluftwm theme"
}

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

	write_list_start "Current herbstluftwm theme:"
	if [[ -L "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		write_kv_list_entry "$(basename $(canonicalise ${EROOT}/etc/herbstluftwm/theme ) )" ""
	elif [[ -e "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		write_kv_list_entry "(not a symlink)" ""
	else
		write_kv_list_entry "(unset)" ""
	fi
}

### list action ###

describe_list() {
	echo "List available herbstluftwm themes"
}

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

	local i targets
	targets=( $(find_targets ) )
	for (( i = 0; i < ${#targets[@]}; i++ )); do
		[[ ${targets[i]} = $(basename "$(canonicalise "${EROOT}/etc/herbstluftwm/theme")") ]] \
			&& targets[i]=$(highlight_marker "${targets[i]}")
	done
	write_list_start "Available herbstluftwm themes implementations:"
	write_numbered_list -m "(none found)" "${targets[@]}"
}

### set action ###

describe_set() {
	echo "Set a new herbstluftwm theme"
}

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

describe_set_parameters() {
	echo "<target>"
}

do_set() {
	if [[ -z "${1}" ]] ; then
		die -q "You didn't give me a theme name"
	elif [[ -n "${2}" ]] ; then
		die -q "Too many parameters"
	elif [[ -L "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		if ! remove_symlink ; then
			die -q "Can't remove existing theme"
		elif ! set_symlink "${1}" ; then
			die -q "Can't set new theme"
		fi
	elif [[ -e "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		die -q "Sorry, ${EROOT}/etc/herbstluftwm/theme confuses me"
	else
		set_symlink "${1}" || die -q "Can't set a new theme"
	fi
}

### update action ###

describe_update() {
	echo "Automatically update the herbstluftwm theme"
}

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 "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		[[ ${1} == "--if-unset" ]] && return
		remove_symlink || die -q "Can't remove existing link"
	fi

	if [[ -e "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		die -q "Can't set a new theme"
	elif ! [[ -z $(find_targets ) ]] ; then
		set_symlink 1 || die -q "Can't set a new theme"
	fi
}

### unset action ###

describe_unset() {
	echo "Unset the herbstluftwm theme"
}

do_unset() {
	if [[ -L "${EROOT}/etc/herbstluftwm/theme" ]] ; then
		remove_symlink || die -q "Can't remove existing link"
	fi
}