# shellcheck shell=bash
about-plugin 'OS X Time Machine functions'

if [[ "${OSTYPE}" != 'darwin'* ]]; then
	_log_warning "This plugin only works with Mac OS X"
	return 1
fi

function time-machine-destination() {
	group "osx-timemachine"
	about "Shows the OS X Time Machine destination/mount point"

	tmutil destinationinfo | grep "Mount Point" | sed -e 's/Mount Point   : \(.*\)/\1/g'
}

function time-machine-list-machines() {
	group "osx-timemachine"
	about "Lists the OS X Time Machine machines on the backup volume"

	local tmdest
	tmdest="$(time-machine-destination)/Backups.backupdb"

	find "$tmdest" -maxdepth 1 -mindepth 1 -type d | grep -v "/\." | while read -r line; do
		echo "${line##*/}"
	done
}

function time-machine-list-all-backups() {
	group "osx-timemachine"
	about "Shows all of the backups for the specified machine"
	param "1: Machine name (optional)"
	example "time-machine-list-all-backups my-laptop"

	# Use the local hostname if none provided
	local COMPUTERNAME BACKUP_LOCATION
	COMPUTERNAME=${1:-$(scutil --get ComputerName)}
	BACKUP_LOCATION="$(time-machine-destination)/Backups.backupdb/$COMPUTERNAME"

	find "$BACKUP_LOCATION" -maxdepth 1 -mindepth 1 -type d | while read -r line; do
		echo "$line"
	done
}

function time-machine-list-old-backups() {
	group "osx-timemachine"
	about "Shows all of the backups for the specified machine, except for the most recent backup"
	param "1: Machine name (optional)"
	example "time-machine-list-old-backups my-laptop"

	# Use the local hostname if none provided
	local COMPUTERNAME BACKUP_LOCATION
	COMPUTERNAME=${1:-$(scutil --get ComputerName)}
	BACKUP_LOCATION="$(time-machine-destination)/Backups.backupdb/$COMPUTERNAME"

	# List all but the most recent one
	find "$BACKUP_LOCATION" -maxdepth 1 -mindepth 1 -type d -name 2\* | sed \$d | while read -r line; do
		echo "$line"
	done
}

# Taken from here: http://stackoverflow.com/a/30547074/1228454
function _tm_startsudo() {
	local -x SUDO_COMMAND="plugin/osx-timemachine: keep 'sudo' token alive during long-run 'tmutil' commands"
	sudo "-${SUDO_ASKPASS:+A}v" # validate without running a command, using `ssh-askpass` if available.
	(while sudo "-${SUDO_ASKPASS:+A}v"; do
		sleep 50
	done) &
	SUDO_PID="$!"
	trap _tm_stopsudo SIGINT SIGTERM
}
function _tm_stopsudo() {
	kill "$SUDO_PID"
	trap - SIGINT SIGTERM
	sudo -k
}

function time-machine-delete-old-backups() {
	group "osx-timemachine"
	about "Deletes all of the backups for the specified machine, with the exception of the most recent one"
	param "1: Machine name (optional)"
	example "time-machine-delete-old-backups my-laptop"

	# Use the local hostname if none provided
	local COMPUTERNAME=${1:-$(scutil --get ComputerName)} _old_backup

	# Ask for sudo credentials only once
	_tm_startsudo

	while read -r _old_backup; do
		# Delete the backup
		sudo tmutil delete "$_old_backup"
	done <<< "$(time-machine-list-old-backups "$COMPUTERNAME")"

	_tm_stopsudo
}
