#
# Copyright (c) 2022-2023, Jesús Daniel Colmenares Oviedo <DtxdF@disroot.org>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# * Redistributions of source code must retain the above copyright notice, this
#   list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above copyright notice,
#   this list of conditions and the following disclaimer in the documentation
#   and/or other materials provided with the distribution.
#
# * Neither the name of the copyright holder nor the names of its
#   contributors may be used to endorse or promote products derived from
#   this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

lib_load "${LIBDIR}/log"
lib_load "${LIBDIR}/sysexits"
lib_load "${LIBDIR}/replace"

lib_list_mountpoints()
{
	local mountpoints
	local total
	local current_index=2
	local fs_spec fs_file

	local types="$1"

	if [ -n "${types}" ]; then
		mount_flags="-t ${types}"
	fi

	mountpoints=`mount ${mount_flags} | sed -Ee 's/^(.+) on (.+) \(.+/\1\n\2/'`

	total=`printf "%s\n" "${mountpoints}" | wc -l`

	while [ ${current_index} -le ${total} ]; do
		fs_spec=`printf "%s\n" "${mountpoints}" | head -${current_index} | tail -n 2 | head -1`
		fs_file=`printf "%s\n" "${mountpoints}" | head -${current_index} | tail -n 2 | tail -1`

		printf "%s\n" "<${fs_spec}> <${fs_file}>"

		current_index=$((current_index+2))
	done
}

lib_mountpoint_mounted()
{
	local entry
	local fs_spec fs_file
	local opt_use_fs_file=1
	local opt_use_fs_spec=0
	local opt_strict=0
	local format="%2 -> %1"
	local types=
	local mountpoint
	local cmp1 cmp2

	if [ $# -eq 0 ]; then
		lib_err ${EX_USAGE} "usage: lib_mountpoint_mounted [-f | -p] [-s] [-F format] [-t [no]type[,type ...]] mountpoint"
	fi

	while getopts ":fpsF:t:" _o; do
		case "${_o}" in
			f)
				opt_use_fs_file=1
				opt_use_fs_spec=0
				;;
			p)
				opt_use_fs_spec=1
				opt_use_fs_file=0
				;;
			s)
				opt_strict=1
				;;
			F)
				format="${OPTARG}"
				;;
			t)
				types="${OPTARG}"
				;;
			*)
				lib_mountpoint_mounted # usage
				;;
		esac
	done
	shift $((OPTIND-1))

	mountpoint="$1"
	if [ -z "${mountpoint}" ]; then
		lib_mountpoint_mounted # usage
	fi

	lib_list_mountpoints "${types}" | while IFS= read -r entry; do
		fs_spec=`printf "%s" "${entry}" | sed -Ee 's/<(.+)> .+/\1/'`
		fs_file=`printf "%s" "${entry}" | sed -Ee 's/.+ <(.+)>/\1/'`

		if [ ${opt_use_fs_file} -eq 1 ]; then
			cmp1="${fs_file}"
			cmp2="${fs_spec}"
		else
			cmp1="${fs_spec}"
			cmp2="${fs_file}"
		fi

		if [ ${opt_strict} -eq 1 ]; then
			if [ "${cmp1}" = "${mountpoint}" ]; then
				lib_multi_replace "${format}" 1 "${cmp1}" 2 "${cmp2}"
				break
			fi
		else
			case "${cmp1}" in
				${mountpoint}*)
					lib_multi_replace "${format}" 1 "${cmp1}" 2 "${cmp2}"
					;;
			esac
		fi
	done
}
