# -*-eselect-*-  vim: ft=eselect
# Copyright 2005-2013 Gentoo Foundation
# Distributed under the terms of the GNU GPL version 2 or later

DESCRIPTION="Manage contributed bash-completion scripts"
MAINTAINER="eselect@gentoo.org"

COMPLETIONS_DIR=${EROOT%/}/usr/share/bash-completion/completions
# blacklist for system-wide disables
COMPLETIONS_GLOBAL_BLACKLIST=${EROOT%}/etc/bash/completion.blacklist
# whitelist for user re-enables
COMPLETIONS_USER_WHITELIST=~/.config/bash_completion.whitelist
# blacklist for user disables
COMPLETIONS_USER_BLACKLIST=~/.config/bash_completion.blacklist

find_targets() {
	local bc

	# Note: safe to cd, we're in a subshell
	cd "${COMPLETIONS_DIR}" || die
	for bc in *; do
		[[ -f ${bc} && ${bc} != *~ ]] && echo "${bc}"
	done | sort -u
}

is_enabled() {
	local state=1

	[[ -n ${USE_GLOBAL} ]] \
		&& grep -q -s "^${1}\$" "${COMPLETIONS_GLOBAL_BLACKLIST}" \
		&& state=0

	if [[ -n ${USE_USER} ]]; then
		grep -q -s "^${1}\$" "${COMPLETIONS_USER_WHITELIST}" \
			&& state=1
		grep -q -s "^${1}\$" "${COMPLETIONS_USER_BLACKLIST}" \
			&& state=0
	fi

	[[ ${state} == 1 ]]
}

post_update() {
	# adjust permissions if necessary
	if [[ -n ${USE_GLOBAL} ]]; then
		chmod a+r "${COMPLETIONS_GLOBAL_BLACKLIST}" || die
	fi

	echo "For the changes to apply to open shells, you may need to run:"
	echo "  complete -r ${*}"
	echo "in each of them."
}

### list action ###

describe_list() {
	echo "List available completions"
}

describe_list_options() {
	echo "--global : Show only global completion state"
	echo "--user : Show only user completion state"
}

do_list() {
	local targets i
	targets=( $(find_targets) )

	# by default, show 'effective' state
	USE_GLOBAL=1
	USE_USER=1

	case "${1}" in
		--global)
			USE_USER=
			shift
			;;
		--user)
			USE_GLOBAL=
			shift
			;;
	esac
	[[ ${#} -ne 0 ]] && die "Invalid or conflicting options"

	for (( i = 0; i < ${#targets[@]}; i++ )); do
		is_enabled ${opts} "${targets[i]}" \
			&& targets[i]=$(highlight_marker "${targets[i]}")
	done

	write_list_start "Available completions:"
	write_numbered_list -m "(none found)" "${targets[@]}"
}

### enable action ###

describe_enable() {
	echo "Enable specified completion(s)"
}

describe_enable_parameters() {
	echo "<target>"
}

describe_enable_options() {
	echo "--global : Affect only global completion state (default when root)"
	echo "--user : Affect only user completion state (default when not root)"
	echo "<target> : Target name or number (from 'list' action)"
}

do_enable() {
	USE_GLOBAL=
	USE_USER=

	case "${1}" in
		--global)
			USE_GLOBAL=1
			shift
			;;
		--user)
			USE_USER=1
			shift
			;;
		*) # defaults
			[[ ${EUID} == 0 ]] && USE_GLOBAL=1 || USE_USER=1
			;;
	esac

	[[ $# -eq 0 ]] && die -q "You didn't specify any completions to enable."

	local bc target targets=( $(find_targets) ) changed=() need_wl=()

	for bc; do
		target=${bc}
		is_number "${target}" && target=${targets[target-1]}

		[[ -z ${target} || ${target} == */* ]] \
			&& die -q "Target \"${bc}\" doesn't appear to be valid!"

		bc=${target}

		# with --global, check global state
		# with --user, check effective state (global+user)
		if USE_GLOBAL=1 is_enabled "${bc}"; then
			# does it exist?
			if ! has "${bc}" "${targets[@]}"; then
				write_error_msg "${bc} doesn't exist"
				continue
			fi

			write_warning_msg "${bc} is not disabled"

			# maybe it's masked per-user?
			if ! USE_USER=1 is_enabled "${bc}"; then
				need_wl+=( "${bc}" )
			fi

			continue
		fi

		# first, handle blacklist requested (global or user)
		local blacklist
		[[ -n ${USE_GLOBAL} ]] \
			&& blacklist=${COMPLETIONS_GLOBAL_BLACKLIST} \
			|| blacklist=${COMPLETIONS_USER_BLACKLIST}

		# (user blacklist may not exist if whitelist is necessary)
		if [[ -f ${blacklist} ]]; then
			sed -i -e "/^${bc}\$/d" "${blacklist}" || die
		fi

		# then, check if it's still blacklisted for user
		# (need to be whitelisted)
		if ! USE_GLOBAL=1 USE_USER=1 is_enabled "${bc}"; then
			if [[ -n ${USE_USER} ]]; then
				# put it on our whitelist if --user
				echo "${bc}" >> "${COMPLETIONS_USER_WHITELIST}" || die
			else
				# otherwise, warn about it
				need_wl+=( "${bc}" )
			fi
		fi

		changed+=( "${bc}" )
	done

	if [[ -n ${need_wl[@]} ]]; then
		write_warning_msg "Note: some of the listed modules are disabled for your user."
		write_warning_msg "You may want to enable them using:"
		write_warning_msg "  eselect bashcomp enable --user ${need_wl[*]}"
		echo
	fi

	if [[ -n ${changed[@]} ]]; then
		post_update "${changed[@]}"
	fi
}

### disable action ###

describe_disable() {
	echo "Disable specified completion(s)"
}

describe_disable_parameters() {
	echo "<target>"
}

describe_disable_options() {
	echo "--global : Affect only global completion state (default when root)"
	echo "--user : Affect only user completion state (default when not root)"
	echo "<target> : Target name or number (from 'list' action)"
}

do_disable() {
	USE_GLOBAL=
	USE_USER=

	case "${1}" in
		--global)
			USE_GLOBAL=1
			shift
			;;
		--user)
			USE_USER=1
			shift
			;;
		*) # defaults
			[[ ${EUID} == 0 ]] && USE_GLOBAL=1 || USE_USER=1
			;;
	esac

	[[ $# -eq 0 ]] && die -q "You didn't specify any completions to disable."

	local bc target targets=( $(find_targets) ) changed=() need_bl=()

	for bc; do
		target=${bc}
		is_number "${target}" && target=${targets[target-1]}

		[[ -z ${target} || ${target} == */* ]] \
			&& die -q "Target \"${bc}\" doesn't appear to be valid!"

		bc=${target}

		# does it exist?
		if ! has "${bc}" "${targets[@]}"; then
			write_error_msg "${bc} doesn't exist"
			continue
		fi

		if ! is_enabled "${bc}"; then
			write_warning_msg "${bc} is disabled"

			# maybe it's whitelisted per-user?
			if USE_USER=1 is_enabled "${bc}"; then
				need_bl+=( "${bc}" )
			fi

			continue
		fi

		# first, handle blacklist requested (global or user)
		local blacklist
		[[ -n ${USE_GLOBAL} ]] \
			&& blacklist=${COMPLETIONS_GLOBAL_BLACKLIST} \
			|| blacklist=${COMPLETIONS_USER_BLACKLIST}
		echo "${bc}" >> "${blacklist}" || die

		# when doing user-wide changes, also clean up the whitelist
		if [[ -n ${USE_USER} ]]; then
			sed -i -e "/^${bc}\$/d" "${COMPLETIONS_USER_WHITELIST}" || die
		else
			# otherwise, check if the user didn't whitelist it
			if USE_USER=1 is_enabled "${bc}"; then
				# and warn about it
				need_bl+=( "${bc}" )
			fi
		fi

		changed+=( "${bc}" )
	done

	if [[ -n ${need_bl[@]} ]]; then
		write_warning_msg "Note: some of the listed modules are enabled for your user."
		write_warning_msg "You may want to disable them using:"
		write_warning_msg "  eselect bashcomp disable --user ${need_bl[*]}"
		echo
	fi

	if [[ -n ${changed[@]} ]]; then
		post_update "${changed[@]}"
	fi
}

### prune action ###

describe_prune() {
	echo "Prune stale blacklist and whitelist entries"
}

describe_prune_options() {
	echo "--global : Prune non-existent global completions"
	echo "--user : Prune non-existent and non-effective user completions"
}

do_prune() {
	local targets i do_global do_user
	targets=( $(find_targets) )

	# by default, do both
	do_global=1
	do_user=1

	case "${1}" in
		--global)
			do_user=
			shift
			;;
		--user)
			do_global=
			shift
			;;
	esac
	[[ ${#} -ne 0 ]] && die "Invalid options"

	local f files=()
	[[ -n ${do_global} ]] && files+=( "${COMPLETIONS_GLOBAL_BLACKLIST}" )
	[[ -n ${do_user} ]] && files+=(
		"${COMPLETIONS_USER_WHITELIST}"
		"${COMPLETIONS_USER_BLACKLIST}"
	)

	for f in "${files[@]}"; do
		local tmpfile=${f}.new

		# try to write it
		touch "${tmpfile}" || die

		while read; do
			# allow comments to pass-through
			if [[ ${REPLY} != '#'* ]]; then
				# prune non-existing files
				has "${REPLY}" "${targets[@]}" || continue

				if [[ ${f} == ${COMPLETIONS_USER_WHITELIST} ]]; then
					# remove stale whitelist entries when not on global bl
					USE_GLOBAL=1 is_enabled && continue

					# or if blacklisted by user
					USE_USER=1 is_enabled || continue
				elif [[ ${f} == ${COMPLETIONS_USER_BLACKLIST} ]]; then
					# remove redundant blacklist entries
					USE_GLOBAL=1 is_enabled || continue
				fi
			fi

			echo "${REPLY}" > "${tmpfile}"
		done < "${f}" || die

		if [[ ! -s ${tmpfile} ]]; then
			# empty, so remove both
			rm "${tmpfile}" "${f}" || die
		else
			# replace
			mv "${tmpfile}" "${f}" || die
		fi
	done
}