#!/bin/bash

### BEGIN INIT INFO
# Provides:	  msm
# Required-Start: $local_fs $remote_fs
# Required-Stop:  $local_fs $remote_fs
# Should-Start:	  $network
# Should-Stop:	  $network
# Default-Start:  2 3 4 5
# Default-Stop:	  0 1 6
# Short-Description:	
# Description:	  
### END INIT INFO


# See http://www.debian.org/doc/debian-policy/ch-opersys.html#s-sysvinit for
# more information on debain init.d scripts, which may help you understand
# this script.


### The configuration file

# Get the MSM_CONF environment variable or use the default location
CONF="${MSM_CONF:-/etc/msm.conf}"


### The Minecraft Server Manager version, use "msm version" to check yours.
VERSION="0.3.4"


### Config variables the user should not need/want to change

# Jar group file which contains the download target URL
declare -r JARGROUP_TARGET="target.txt"
# Jar group directory name to download new jars to, is deleted afterwards
declare -r JARGROUP_DOWNLOAD_DIR="downloads"
# The server configuration file name
declare -r SERVER_CONF_NAME="server.properties"
# The start of a regex to find a log line
declare -r LOG_REGEX="^[0-9]{4}-[0-9]{2}-[0-9]{2} [0-9]{2}:[0-9]{2}:[0-9]{2} \[.*\]"


### Script State Variables

# "true" whilst the script is counting down a delay to stop the server
declare STOP_COUNTDOWN

# "true" whilst the script is counting down a delay to restart the server
declare RESTART_COUNTDOWN


### Utility Functions

# Executes the command "$2" as user "$1"
# $1: The user to execute the command as
# $2: The command to execute
as_user() {
	local user="$(whoami)"
	if [ "$user" == "$1" ]; then
		bash -c "$2"
	else
		if [ "$user" == "root" ]; then
			su - "$1" -s /bin/bash -c "$2"
		else
			error_exit INVALID_USER "This command must be executed as the user \"$1\" or \"root\"."
		fi
	fi
}

# Executes the command "$1" as SERVER_USER but returns stderr instead
as_user_stderr() {
	as_user "$@"  > /dev/null 2>&1
}

# Echo to stderr
echoerr() {
	echo "$@" 1>&2
}

# Exit's the script 
error_exit() {
	case "$1" in
		INVALID_USER) code=64;;
		INVALID_COMMAND) code=65;;
		INVALID_ARGUMENT) code=66;;
		SERVER_STOPPED) code=67;;
		SERVER_RUNNING) code=68;;
		NAME_NOT_FOUND) code=69;;
		FILE_NOT_FOUND) code=70;;
		DUPLICATE_NAME) code=71;;
		LOGS_NOT_ROLLED) code=72;;
		CONF_ERROR) code=73;;
		FATAL_ERROR) code=74;;
	esac
	
	echo "${2:-"Unknown Error"}" 1>&2
	exit "${code:-$1}"
}

# A function used to print debug messages to stdout. Prevents messages from
# appearing unless in debug mode, and allows debug statements to be easily
# distinguished from necessary echo statements.
# $1: The message to output
debug() {
	if [[ "$DEBUG" == "true" ]]; then
		echoerr "$1"
	fi
}

# Determines whether "$1" is a valid name for a server or jar group directory
# It must only contain upper or lower case letters, digits, dashes or
# underscores.
# It must also not be one of a list of reserved names.
# $1: The name to check
is_valid_name() {
	local valid="^[a-zA-Z0-9\_\-]+$"
	local invalid="^(start|stop|restart|version|server|jargroup|all)$"
	
	if [[ "$1" =~ $valid ]]; then
		if [[ "$1" =~ $invalid ]]; then
			error_exit INVALID_ARGUMENT "Invalid name \"$1\": A name may not be any of the following reserved worlds \"start\", \"stop\", \"restart\", \"server\", \"version\", \"jargroup\" or \"all\"."
		else
			return 0
		fi
	else
		error_exit INVALID_ARGUMENT "Invalid name \"$1\": A name may only contain letters, numbers, dashes and unscores."
	fi
}

# Gets the latest jar from a jar group, based upon the date and time encoded
# in the file name.
# $1: The directory to search
get_latest_file() {
	local best_time=0
	local best_file=""
	
	while IFS= read -r -d $'\0' file; do
		# Remove the path, leaving just the file name
		local date_time="$(basename "$file" | awk -F '-' '{print $1 "-" $2 "-" $3 " " $4 ":" $5 ":" $6}')"
		
		# Get the time in seconds since 1970 from file name
		local seconds="$(date -d "$date_time" "+%s" 2> /dev/null)"
		
		# If that is newer than the current best, override variables
		if [[ "$seconds" -gt "$best_time" ]]; then
			best_time="$seconds"
			best_file="$file"
		fi
	done < <(find "$1" -maxdepth 1 -type f -print0)
	
	echo "$best_file"
}

# Returns the current time as a UNIX timestamp (in seconds since 1970)
now() {
	date +%s
}


### Log Utility Functions

# Gets the UNIX timestamp for a server log line
# $1: A server log line
# returns: Time in seconds since 1970-01-01 00:00:00 UTC
log_line_get_time() {
	time_string="$(echo "$1" | awk '{print $1 " " $2}')"
	date -d "$time_string" "+%s" 2> /dev/null
}


### World Utility Functions

# Moves a world to RAM
# $1: the ID of the world to move
world_to_ram() {
	if [ ! -z "$RAMDISK_STORAGE_PATH" ]; then
		as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "mkdir -p \"${WORLD_RAMDISK_PATH[$1]}\" && rsync -rt --exclude '$(basename "${WORLD_FLAG_INRAM[$1]}")' \"${WORLD_PATH[$1]}/\" \"${WORLD_RAMDISK_PATH[$1]}\""
	fi
}

# Moves a world in RAM to disk
# $1: the ID of the world to move
world_to_disk() {
	as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "rsync -rt --exclude '$(basename "${WORLD_FLAG_INRAM[$1]}")' \"${WORLD_RAMDISK_PATH[$1]}/\" \"${WORLD_PATH[$1]}\""
}

# Toggles a worlds ramdisk state
# $1: The ID of the world
world_toggle_ramdisk_state() {
	if [ -f "${WORLD_FLAG_INRAM[$1]}" ]; then
		echo -n "Removing RAM flag from world \"${WORLD_NAME[$1]}\"... "
		as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "rm -f \"${WORLD_FLAG_INRAM[$1]}\""
		echo "Done."
		
		echo -n "Removing world \"${WORLD_NAME[$1]}\" from RAM... "
		as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "rm -r \"${WORLD_RAMDISK_PATH[$1]}\""
		echo "Done."
	else
		echo -n "Adding RAM flag to world \"${WORLD_NAME[$1]}\"... "
		as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "touch \"${WORLD_FLAG_INRAM[$1]}\""
		echo "Done."
		
		echo -n "Copying world to RAM... "
		world_to_ram "$1"
		echo "Done."
	fi
	echo "Changes will only take effect after server is restarted."	
}

# Backs up a world
# $1: The ID of the world
world_backup() {
	echo -n "Backing up world \"${WORLD_NAME[$1]}\"... "
	
	file_name="$(date "+%F-%H-%M-%S").zip"
	local server_id="${WORLD_SERVER_ID[$1]}"
	local containing_dir="$(dirname "${WORLD_PATH[$1]}")"
	local dir_name="$(basename "${WORLD_PATH[$1]}")"
	as_user "${SERVER_USER_NAME[$server_id]}" "mkdir -p \"${WORLD_BACKUP_PATH[$1]}\" && cd \"$containing_dir\" && zip -rq \"${WORLD_BACKUP_PATH[$1]}/${file_name}\" \"${dir_name}\""

	echo "Done."
}

# Activates a world
# $1: The ID of the world
world_activate() {
	if [ -d "${WORLD_INACTIVE_PATH[$1]}" ]; then
		echo -n "Moving world \"${WORLD_NAME[$1]}\" to the active worldstorage directory... "
		local new_path="${WORLD_ACTIVE_PATH[$1]}"
		as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "mkdir -p \"$new_path\" && mv \"${WORLD_INACTIVE_PATH[$1]}\" \"$new_path\""
		echo "Done."
	else
		if [ -d "${WORLD_ACTIVE_PATH[$1]}" ]; then
			echo "World \"${WORLD_NAME[$1]}\" is already activate."
		else
			error_exit DIR_NOT_FOUND "Directory \"${WORLD_INACTIVE_PATH[$1]}\" could not be found."
		fi
	fi
}

# Deactivates a world
# $1: The ID of the world
world_deactivate() {
	if server_is_running "${WORLD_SERVER_ID[$1]}"; then
		exit_error 68 "Worlds cannot be deactivated whilst the server is running."
	else
		if [ -d "${WORLD_ACTIVE_PATH[$1]}" ]; then
			echo -n "Moving world \"${WORLD_NAME[$1]}\" to the inactive worldstorage directory... "
			local new_path="${WORLD_INACTIVE_PATH[$1]}"
			as_user "${SERVER_USER_NAME[${WORLD_SERVER_ID[$1]}]}" "mkdir -p \"$new_path\" && mv \"${WORLD_PATH[$1]}\" \"$new_path\""
			echo "Done."
		else
			if [ -d "${WORLD_INACTIVE_PATH[$1]}" ]; then
				echo "World \"${WORLD_NAME[$1]}\" is already deactivate."
			else
				exit_error DIR_NOT_FOUND "Directory \"${WORLD_ACTIVE_PATH[$1]}\" could not be found."
			fi
		fi
	fi
}

### Server Utility Functions

# Returns the ID for a server.
# An ID is given to a server when loaded into memory, and can be used to lookup
# config information for that server
# $1: The name of the server
server_get_id() {
	for ((i=0; i<$num_servers; i++)); do
		if [[ "${SERVER_NAME[$i]}" == "$1" ]]; then
			echo "$i"
			return 0
		fi
	done
	
	error_exit NAME_NOT_FOUND "Could not find id for server name \"$1\"."
}

# Returns the ID of a server's world.
# $1: The ID of the server
# $2: The name of the world
server_world_get_id() {
	if [ -d "${SERVER_WORLD_STORAGE[$1]}/$2" ] || [ -d "${SERVER_WORLD_STORAGE_INACTIVE[$1]}/$2" ]; then
		# If the directory exists
		
		local start="${SERVER_WORLD_OFFSET[$1]}"
		local max="$(( $i + ${SERVER_NUM_WORLDS[$1]} ))"
	
		# For each of the servers worlds:
		for ((i=$start; i<$max; i++)); do
			if [[ "${WORLD_NAME[$i]}" == "$2" ]]; then
				echo "$i"
				return 0
			fi
		done
	fi
	
	error_exit NAME_NOT_FOUND "Could not find id for world \"$2\" for server \"${SERVER_NAME[$1]}\"."
}

# Returns 0 if the server $1 is running and 1 if not
# $1: The ID of the server
server_is_running() {
	if ps ax | grep -v grep | grep "${SERVER_SCREEN_NAME[$1]} ${SERVER_INVOCATION[$1]}" > /dev/null
	then
		return 0
	else
		return 1
	fi
}

# Creates symbolic links in the server directory (SERVER_STORAGE_PATH) for each
# of the Minecraft worlds located in the world storage directory.
# $1: The id of the server for which links should be ensured
server_ensure_links() {
	echo -n "Maintaining world symbolic links... "
	local start="${SERVER_WORLD_OFFSET[$1]}"
	local max="$(( $start + ${SERVER_NUM_WORLDS[$1]} ))"
	local output="false"
	
	for ((i=$start; i<$max; i++)); do
		if [[ "${WORLD_STATUS[$i]}" != "active" ]]; then
			# Remove the symbolic link if it exists
			as_user "${SERVER_USER_NAME[$1]}" "rm -f \"${WORLD_LINK[$i]}\""
			continue
		fi
		
		# -L checks for the path being a link rather than a file
		# ! -a, since it is within double square brackets means: the negation of
		# the existence of the file. In other words: true if does not exist
		if [[ -L "${WORLD_LINK[$i]}" || ! -a "${WORLD_LINK[$i]}" ]]; then
			# If there is a symbolic link in the server direcotry to this world,
			# or there is not a directory in the server directory containing this world.
			
			# Get the original file path the symbolic link is pointing to
			# If there is no link, link_target will contain nothing
			link_target="$(readlink "${WORLD_LINK[$i]}")"
			
			if "${WORLD_INRAM[$i]}"; then
				# If this world is marked as loaded into RAM

				if [ "${link_target}" != "${WORLD_RAMDISK_PATH[$i]}" ]; then
					# If the symbolic link does not point to the RAM version of the world

					# Remove the symbolic link if it exists
					as_user "${SERVER_USER_NAME[$1]}" "rm -f \"${WORLD_LINK[$i]}\""

					# Create a new symbolic link pointing to the RAM version of the world
					as_user "${SERVER_USER_NAME[$1]}" "ln -s \"${WORLD_RAMDISK_PATH[$i]}\" \"${WORLD_LINK[$i]}\""
				fi
			else
				# Otherwise the world is not loaded into RAM, and is just on disk

				if [ "${link_target}" != "${WORLD_PATH[$i]}" ]; then
					# If the symbolic link does not point to the disk version of the world

					# Remove the symbolic link if it exists
					as_user "${SERVER_USER_NAME[$1]}" "rm -f \"${WORLD_LINK[$i]}\""

					# Create a new symbolic link pointing to the disk version of the world
					as_user "${SERVER_USER_NAME[$1]}" "ln -s \"${WORLD_PATH[$i]}\" \"${WORLD_LINK[$i]}\""
				fi
			fi
		else
			echoerr -en "\n    Error: Could not create link for world \"${WORLD_NAME[$i]}\". The file \"${WORLD_LINK[$i]}\" already exists, and should not be overwritten automatically. Either remove this file, or rename \"${WORLD_NAME[$i]}\"."
			output="true"
		fi
	done
	
	if [[ "$output" == "true" ]]; then
		echo -e "\nDone."
	else
		echo "Done."
	fi
}

# Moves a servers worlds into RAM
# $1: The ID of the server
server_worlds_to_ram() {
	# Only proceed if there is a ramdisk path set in config
	if [ ! -z "$RAMDISK_STORAGE_PATH" ]; then
		echo -n "Synchronising flagged worlds on disk to RAM... "
		local i="${SERVER_WORLD_OFFSET[$1]}"
		local max="$(( $i + ${SERVER_NUM_WORLDS[$1]} ))"
		
		# For each of the servers worlds:
		while [[ "$i" -lt "$max" ]]; do
			if "${WORLD_INRAM[$i]}" && [ -L "${WORLD_LINK[$i]}" ]; then
				world_to_ram "$i"
			fi
			
			i="$(( $i + 1 ))"
		done
		echo "Done."
	fi
}

# Moves a servers "in RAM" worlds back to disk
# $1: The ID of the server
server_worlds_to_disk() {
	if [ ! -z "$RAMDISK_STORAGE_PATH" ]; then
		echo -n "Synchronising worlds in RAM to disk... "
		local i="${SERVER_WORLD_OFFSET[$1]}"
		local max="$(( $i + ${SERVER_NUM_WORLDS[$1]} ))"
		
		# For each of the servers worlds:
		while [[ "$i" -lt "$max" ]]; do
			if [ -d "${WORLD_RAMDISK_PATH[$i]}" ]; then
				world_to_disk "$i"
			fi
			
			i="$(( $i + 1 ))"
		done
		echo "Done."
	fi
}

# Watches a server's log for a specific line
# $1: The ID for the server
# $2: A UNIX timestamp (seconds since 1970) which the $3 line must be after
# $3->: The line or lines in the log to wait for
# returns: When the line is found
server_log_get_line() {
    # Make sure there is a server log to check
    as_user "${SERVER_USER_NAME[$1]}" "touch ${SERVER_LOG[$1]}"

	while read line; do
		line_time="$(log_line_get_time "$line")"

		# If the entry is old enough
		if [[ "$line_time" -ge "$2" ]]; then
			for search_line in "${@:3}"; do
				local regex="${LOG_REGEX} ${search_line}"
				# and matches the regular expression
				if [[ "$line" =~ $regex ]]; then
					echo "${line}"
					return 0
				fi
			done
		fi
	done < <(as_user "${SERVER_USER_NAME[$1]}" "tail --pid=$$ --follow --lines=100 --sleep-interval=0.1 \"${SERVER_LOG[$1]}\"")
}

# The same as server_log_get_line, but does not print the line to stdout
# when found.
server_log_wait_for_line() {
	server_log_get_line "$@" > /dev/null
}

# Sends as string to a server for execution
# $1: The ID of the server
# $2: The line of text to enter into the server console
server_eval() {
	as_user "${SERVER_USER_NAME[$1]}" "screen -p 0 -S ${SERVER_SCREEN_NAME[$1]} -X eval 'stuff \"$2\"\015'"
}

# The same as server_eval, but also waits for a log entry before returning
# $1: The ID of the server
# $2: A line of text to enter into the server console
# $3->: The line or lines of text in the log to wait for
# stdout: The full entry found in the logs
server_eval_and_get_line() {
	time_now="$(now)"
	server_eval "$1" "$2"
	server_log_get_line "$1" "$time_now" "${@:3}"
}

# The same as server_eval_and_get_line, but does not print anything to stdout
server_eval_and_wait() {
	server_eval_and_get_line "$@" > /dev/null
}

# Gets the process ID for a server if running, otherwise it outputs nothing
# $1: The ID of the server
server_pid() {
	ps ax | grep -v grep | grep "${SERVER_SCREEN_NAME[$1]} ${SERVER_INVOCATION[$1]}" | awk '{print $1}'
}

# Waits for a server to stop by polling 10 times a second
# This approach is fairyl intensive, so only use when you are expecting the
# server to stop soon
# $1: The ID of the server to wait for
server_wait_for_stop() {
	local pid="$(server_pid "$1")"
	
	# if the process is still running, wait for it to stop
	if [ ! -z "$pid" ]; then
		while ps -p "$pid" > /dev/null; do
			sleep 0.1
		done
	fi
}

# Sets a server's active/inactive state
# $1: The ID of the server
# $2: A string containing "active" or "inactive"
server_set_active() {
	case "$2" in
		active)
			as_user "${SERVER_USER_NAME[$1]}" "touch \"${SERVER_FLAG_ACTIVE[$1]}\""
			SERVER_ACTIVE[$1]="true"
			;;
		inactive)
			as_user "${SERVER_USER_NAME[$1]}" "rm -f \"${SERVER_FLAG_ACTIVE[$1]}\""
			SERVER_ACTIVE[$1]="false"
			;;
		*)
			error_exit INVALID_ARGUMENT "Invalid argument."
			;;
	esac
}


### Jar Group Functions

# Lists the jar files grouped by jar groups.
jargroup_list() {
	if [[ -d "${JAR_STORAGE_PATH}" ]]; then
		local jargroup_name
		local jar_name
	
		while IFS= read -r -d $'\0' jargroup_path; do
			jargroup_name="$(basename "${jargroup_path}")"
			echo "$jargroup_name"
			while IFS= read -r -d $'\0' jar_path; do
				jar_name="$(basename "${jar_path}")"
				if [[ "$jar_name" =~ ^[0-9]{4}-[0-9]{2}-[0-9]{2}- ]]; then
					echo "    $jar_name"
				fi
			done < <(find "${JAR_STORAGE_PATH}/${jargroup_name}" -mindepth 1 -maxdepth 1 -type f -print0)
		done < <(find "${JAR_STORAGE_PATH}" -mindepth 1 -maxdepth 1 -type d -print0)
	fi
}

# Creates a new jargroup
# $1: The name for the jargroup
jargroup_create() {
	if is_valid_name "$1"; then
		if [[ ! -d "$JAR_STORAGE_PATH/$1" ]]; then
			printf "Creating jar group... "
			
			local error="$(as_user_stderr "$USERNAME" "mkdir -p \"$JAR_STORAGE_PATH/$1\"")"
			if [[ "$error" != "" ]]; then
				echo "Failed."
				error_exit FILE_NOT_FOUND "$error"
			fi
			
			error="$(as_user "$USERNAME" "echo \"$2\" > \"$JAR_STORAGE_PATH/$1/$JARGROUP_TARGET\"")"
			if [[ "$error" != "" ]]; then
				echo "Failed."
				error_exit FILE_NOT_FOUND "$error"
			fi
			
			echo "Done."
		else
			error_exit DUPLICATE_NAME "A jar group with that name already exists."
		fi
	fi
}

# Downloads the latest version for a jargroup, using the target URL for that
# group. Saves the download with the date and time encoded in the start of the
# file name, in the jar group directory in question. Removes the file if there
# is no difference between it and the current version.
# $1: The jargroup name to download the latest version for
jargroup_getlatest() {
	if is_valid_name "$1"; then
		if [[ -d "$JAR_STORAGE_PATH/$1" ]]; then
			if [[ -f "$JAR_STORAGE_PATH/$1/$JARGROUP_TARGET" ]]; then
				printf "Downloading latest version... "
			
				# Try and make 
				local error="$(as_user_stderr "$USERNAME" "mkdir -p '$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR'")"
				if [[ "$error" != "" ]]; then
					echo "Failed."
					error_exit FILE_NOT_FOUND "$error"
				fi
			
				as_user "$USERNAME" "wget --quiet --trust-server-names --no-check-certificate --input-file='$JAR_STORAGE_PATH/$1/$JARGROUP_TARGET' --directory-prefix='$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR'"
				echo "Done."
			
				local num_files="$(as_user "$USERNAME" "ls -1 '$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR' | wc -l")"
			
				if [[ "$num_files" == 1 ]]; then
					# There was 1 file downloaded
				
					local file_name="$(ls -1 "$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR")"
					local new_name="$(date +%F-%H-%M-%S)-$file_name"
					local most_recent_jar="$(get_latest_file "$JAR_STORAGE_PATH/$1")"
					
				
					if [[ ! -f "$most_recent_jar" ]] || ! diff "$most_recent_jar" "$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR/$file_name" > /dev/null; then
						# There is not a previous version to do a comparison against, or
						# The previous version is different:
						# Add it to the group
					
						[[ -f "$most_recent_jar" ]]
						local was_previous="$?"
					
						as_user "$USERNAME" "mv '$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR/$file_name' '$JAR_STORAGE_PATH/$1/$new_name'"
					
						if [[ ! -z "$most_recent_jar" ]]; then
							echo "Downloaded version was different to previous latest. Saved as \"$JAR_STORAGE_PATH/$1/$new_name\"."
						else
							echo "Saved as \"$JAR_STORAGE_PATH/$1/$new_name\"."
						fi
					else
						echo "Existing version \"$JAR_STORAGE_PATH/$1/$new_name\" was already up to date."
					fi
				
				elif [[ "$num_files" == 0 ]]; then
					# No file was downloaded
					echo "Failed. No files were downloaded."
				else
					# Multiple files were
					echo "Error. URL downloads multiple files."
				fi
			
				# Clean up the temp download folder
				as_user "$USERNAME" "rm -fr '$JAR_STORAGE_PATH/$1/$JARGROUP_DOWNLOAD_DIR'"
			else
				error_exit FILE_NOT_FOUND "Target URL not found, use $0 jargroup seturl <download-url>"
			fi
		else
			error_exit NAME_NOT_FOUND "There is no jar group with the name \"$1\"."
		fi
	fi
}

# Deletes an existing jargroup
# $1: The name of the existing jargroup
jargroup_delete() {
	if is_valid_name "$1"; then
		if [[ -d "$JAR_STORAGE_PATH/$1" ]]; then
			printf "Are you sure you want to delete this jar group [y/N]: "
		
			read answer
			if [[ "$answer" =~ ^y|Y|yes$ ]]; then
				as_user "$USERNAME" "rm -rf \"$JAR_STORAGE_PATH/$1\""
				echo "Jar group deleted."
			else
				echo "Jar group was NOT deleted."
			fi
		else
			error_exit NAME_NOT_FOUND "There is no jar group with the name \"$1\"."
		fi
	fi
}

# Renames an existing jargroup
# $1: The name of the existing jargroup
# $2: The new name
jargroup_rename() {
	if is_valid_name "$1"; then
		if [[ -d "$JAR_STORAGE_PATH/$1" ]]; then
			# If the jar group name is valid,
			# and there is no other jar group with the name $1
		
			if is_valid_name "$2"; then
				if [[ -e "$JAR_STORAGE_PATH/$2" ]]; then
					error_exit DUPLICATE_NAME "Could not be renamed, there is already a jar group with the name \"$2\"."
				else
					# TODO: Update any symbolic links which point to a jar in this directory
					as_user "$USERNAME" "mv '$JAR_STORAGE_PATH/$1' '$JAR_STORAGE_PATH/$2'"
					echo "Renamed jar group \"$1\" to \"$2\"."
				fi
			fi
		else
			error_exit NAME_NOT_FOUND "There is no jar group with the name \"$1\"."
		fi
	fi
}


### Server Functions

# Echos a list of servers in the SERVER_STORAGE_PATH
server_list() {
	if [ -d "$SERVER_STORAGE_PATH" ]; then
		ls -1 "$SERVER_STORAGE_PATH"
	else
		echo "[There are no servers]"
	fi	
}

# Creates a new server
# $1: The server name to create
server_create() {
	if is_valid_name "$1"; then
		if [[ -d "$SERVER_STORAGE_PATH/$1" ]]; then
			error_exit DUPLICATE_NAME "A server with that name already exists."
		else
			printf "Creating server directory... "
			as_user "$USERNAME" "mkdir -p '$SERVER_STORAGE_PATH/$1'"
			as_user "$USERNAME" "touch '$SERVER_STORAGE_PATH/$1/$DEFAULT_WHITELIST'"
			as_user "$USERNAME" "touch '$SERVER_STORAGE_PATH/$1/$DEFAULT_BANNED_IPS'"
			as_user "$USERNAME" "touch '$SERVER_STORAGE_PATH/$1/$DEFAULT_BANNED_PLAYERS'"
			as_user "$USERNAME" "touch '$SERVER_STORAGE_PATH/$1/$DEFAULT_OPS'"
			as_user "$USERNAME" "touch '$SERVER_STORAGE_PATH/$1/$DEFAULT_PROPERTIES'"
			echo "Done."
			
			# Now that the new server has been created, we must call init again
			# to ensure it is recognised.
			init
			
			# TODO: Handle server default setup stuff better than just using
			#       the "minecraft" jar group. And make it configurable.
			if [ -d "$JAR_STORAGE_PATH/minecraft" ]; then
				server_set_jar "$(server_get_id "$1")" "minecraft"
			fi
		fi
	fi
}

# Deletes an existing server
# $1: The server name to delete
server_delete() {
	if is_valid_name "$1"; then
		if [[ -d "$SERVER_STORAGE_PATH/$1" ]]; then
			printf "Are you sure you want to delete this server and its worlds (note: backups are preserved) [y/N]: "

			read answer
			if [[ "$answer" =~ ^(y|Y|yes)$ ]]; then
				# TODO: stop the server if running first
				as_user "$USERNAME" "rm -rf '$SERVER_STORAGE_PATH/$1'"
				echo "Server deleted."
			else
				echo "Server was NOT deleted."
			fi
		else
			error_exit NAME_NOT_FOUND "There is no server with the name \"$1\"."
		fi
	fi
}

# Renames an existing server
# $1: The server name to change
# $2: The new name for the server
server_rename() {
	if is_valid_name "$1"; then
		if [ -d "$SERVER_STORAGE_PATH/$1" ]; then
			# If the server name is valid and exists
			
			local existing_id="$(server_get_id "$1")"
			if server_is_running "$existing_id"; then
				error_exit SERVER_RUNNING "Can only rename a stopped server."
			else
				if is_valid_name "$2"; then
					# If the server name is valid
					if [[ -e "$SERVER_STORAGE_PATH/$2" ]]; then
						# and there is not already a server with the name $2
						error_exit DUPLICATE_NAME "Could not be renamed, there is already a server with the name \"$2\"."
					else
						as_user "$USERNAME" "mv '$SERVER_STORAGE_PATH/$1' '$SERVER_STORAGE_PATH/$2'"
						echo "Renamed server \"$1\" to \"$2\"."
					fi
				fi
			fi
		else
			error_exit NAME_NOT_FOUND "There is no server with the name \"$1\"."
		fi
	fi
}

# Starts a single server
# $1: The ID of the server
server_start() {
	if server_is_running "$1"; then
		echo "Server \"${SERVER_NAME[$1]}\" is already running!"
	else
		server_ensure_links "$1"
		server_worlds_to_ram "$1"

		local time_now="$(now)"
		
		printf "Starting server... "
		as_user "${SERVER_USER_NAME[$1]}" "cd \"${SERVER_PATH[$1]}\" && screen -dmS \"${SERVER_SCREEN_NAME[$1]}\" ${SERVER_INVOCATION[$1]}"
		server_log_wait_for_line "$1" "$time_now" "${SERVER_CONFIRM_START[$1]}"
		
		echo "Done."
	fi
}

# Sends the "save-all" command to a server
# $1: The ID of the server
server_save_all() {
	if server_is_running "$1"; then
		echo -n "Forcing save... "
		
		# Send the "save-all" command and wait for it to finish
		server_eval_and_wait "$1" "save-all" "${SERVER_CONFIRM_SAVE_ALL[$1]}"
		
		echo "Done."
	else
		echo "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Sends the "save-off" command to a server
# $1: The ID of the server
server_save_off() {
	if server_is_running "$1"; then
		echo -n "Disabling level saving... "
		
		# Send the "save-off" command and wait for it to finish
		server_eval_and_wait "$1" "save-off" "${SERVER_CONFIRM_SAVE_OFF[$1]}"
		
		echo "Done."
		
		# Writes any in-memory data manged by the kernel to disk
		sync
	else
		echo "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Sends the "save-on" command to a server
# $1: The ID of the server
server_save_on() {
	if server_is_running "$1"; then
		echo -n "Enabling level saving... "
		
		# Send the "save-on" command and wait for it to finish
		server_eval_and_wait "$1" "save-on" "${SERVER_CONFIRM_SAVE_ON[$1]}"
		
		echo "Done."
	else
		echo "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Stops a single server after a delay
# $1: The ID of the server
server_stop() {
	if server_is_running "$1"; then
		# Change the state of the script
		STOP_COUNTDOWN[$1]="true"
	
	    server_eval "$1" "say ${SERVER_STOP_MESSAGE[$1]}"
	    echo "Issued the warning \"${SERVER_STOP_MESSAGE[$1]}\" to players."
	
		echo -n "Shutting down... "
	
		for ((i="${SERVER_STOP_DELAY[$1]}"; i>0; i--)); do
			tput sc # Save cursor position
			echo -n "in $i seconds."
			sleep 1
		
			tput rc # Restore cursor to position of last `sc'
			tput el # Clear to end of line
		done
	
		echo -e "Now."
		server_stop_now "$1"
   	else
		echo "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Stops a single server right now
# $1: The ID of the server
server_stop_now() {
	if server_is_running "$1"; then
		server_save_all "$1"
		
		echo -n "Stopping the server... "
		
		server_eval "$1" "stop"
		STOP_COUNTDOWN[$1]="false"
		RESTART_COUNTDOWN[$1]="false"
		server_wait_for_stop "$1"
		
		echo "Done."
		
		# Synchronise all worlds in RAM to disk
		server_worlds_to_disk "$1"
	else
		echo "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Restarts a single server after a delay
# $1: The ID of the server 
server_restart() {
	# Restarts the server if it is already running
	if server_is_running "$1"; then
		# Change the state of the script
		RESTART_COUNTDOWN[$1]="true"
	
	    server_eval "$1" "say ${SERVER_RESTART_MESSAGE[$1]}"
	    echo "Issued the warning \"${SERVER_RESTART_MESSAGE[$1]}\" to players."
	
		echo -n "Restarting... "
	
		for ((i="${SERVER_STOP_DELAY[$1]}"; i>0; i--)); do
			tput sc # Save cursor position
			echo -n "in $i seconds."
			sleep 1
		
			tput rc # Restore cursor to position of last `sc'
			tput el # Clear to end of line
		done
	
		echo -e "Now."
		
		server_stop_now "$1"
	fi
	
	server_start "$1"
}

# Restarts a single server right away
# $1: The ID of the server
server_restart_now() {
	# Restarts the server if it is already running
	if server_is_running "$1"; then
		server_stop_now "$1"
	fi
	
	server_start "$1"
}

# List the worlds available for a server
# $1: The ID of the server
server_worlds_list() {
	local i="${SERVER_WORLD_OFFSET[$1]}"
	local max="$(( $i + ${SERVER_NUM_WORLDS[$1]} ))"
	
	# For each of the servers worlds:
	while [[ "$i" -lt "$max" ]]; do
		if "${WORLD_INRAM[$i]}"; then
			echo "[RAM] ${WORLD_NAME[$i]}"
		else
			echo "[DSK] ${WORLD_NAME[$i]}"
		fi
		
		i="$(( $i + 1 ))"
	done
}

# Backs up the worlds for a server
# $1: The ID of the server
server_worlds_backup() {
	local i="${SERVER_WORLD_OFFSET[$1]}"
	local max="$(( $i + ${SERVER_NUM_WORLDS[$1]} ))"

	# For each of the servers worlds:
	while [[ "$i" -lt "$max" ]]; do
		world_backup "$i"
		i="$(( $i + 1 ))"
	done
}

# Moves a servers log into another file, leaving the original log file empty
# $1: The ID of the server
server_log_roll() {
	# Moves and Gzips the logfile, a big log file slows down the
	# server A LOT (what was notch thinking?)

	printf "Rolling server logs... "
	
	if [ -e "${SERVER_LOG[$1]}" ]; then
		file_name="${SERVER_NAME[$1]}-$(date +%F-%H-%M-%S).log"
		as_user "${SERVER_USER_NAME[$1]}" "mkdir -p \"${SERVER_LOG_archive_path[$1]}\" && cp \"${SERVER_LOG[$1]}\" \"${SERVER_LOG_archive_path[$1]}/${file_name}\" && gzip \"${SERVER_LOG_archive_path[$1]}/${file_name}\""
		
		if [ -e "${SERVER_LOG_archive_path[$1]}/${file_name}.gz" ]; then
			as_user "${SERVER_USER_NAME[$1]}" "cp \"/dev/null\" \"${SERVER_LOG[$1]}\""
			as_user "${SERVER_USER_NAME[$1]}" "echo \"Previous logs can be found at \\\"${SERVER_LOG_archive_path[$1]}\\\"\" > \"${SERVER_LOG[$1]}\""
		else
			echo "Failed."
			error_exit LOGS_NOT_ROLLED "Logs were not rolled."
		fi
	fi
	
	echo "Done."
}

# Backups a server's directory
# $1: The ID of the server
server_backup() {
	echo -n "Backing up the entire server directory... "
	
	zip_flags="-rq"
	# Add the "y" flag if symbolic links should not be followed
	if [ "${SERVER_COMPLETE_BACKUP_FOLLOW_SYMLINKS[$1]}" != "true" ]; then
		zip_flags="${zip_flags}y"
	fi
	
	# Zip up the server directory
	file_name="${SERVER_BACKUP_PATH[$1]}/$(date "+%F-%H-%M-%S").zip"
	as_user "${SERVER_USER_NAME[$1]}" "mkdir -p \"${SERVER_BACKUP_PATH[$1]}\" && cd \"$SERVER_STORAGE_PATH\" && zip ${zip_flags} \"${file_name}\" \"${SERVER_NAME[$1]}\""
	
	echo "Done."
}

# Sets a server's jar file
# $1: The ID of the server
# $2: The name of the jar group
# $3: Optionally, a specific jar to use.
server_set_jar() {
	if [ -d "$JAR_STORAGE_PATH/$2" ]; then
		
		if [ -z "$3" ]; then
			# If a specific jar file is not mentioned
			
			# Download the latest version
			jargroup_getlatest "$2"
			local jar="$(get_latest_file "$JAR_STORAGE_PATH/$2")"
		else
			# If a specific jar IS mentioned use that
			local jar="$JAR_STORAGE_PATH/$2/$3"
			
			if [[ ! -e "$jar" ]]; then
				error_exit NAME_NOT_FOUND "There is no jar named \"$3\" in jargroup \"$2\"."
			fi
		fi
		
		if [[ ! -z "$jar" ]]; then
			as_user "${SERVER_USER[$1]}" "ln -sf \"$jar\" \"${SERVER_JAR[$1]}\""
			echo "Server \"${SERVER_NAME[$1]}\" is now using \"$jar\"."
		fi
	else
		error_exit NAME_NOT_FOUND "There is no jargorup named \"$2\"."
	fi
}

# Lists the players currently connected to a server
# $1: The ID of the server
server_connected() {
	if server_is_running "$1"; then
		local line="$(server_eval_and_get_line "$1" "list" "Connected players:")"
		
		# Cuts the start off the line, and the last three (invisible)
		# characters from the end.
		local players="${line:46}"
		
		if [ -z "$players" ]; then
			echo "No players are connected."
		else
			echo "$players"
		fi
	else
		echo "Server \"${SERVER_NAME[$1]}\" is not running. No users are connected."
	fi
}


### Manager Functions

# Stops all running servers after a servers specified delay
# $1: String containing "stop" or "restart". Represents whether the stop is 
#     with a mind to stop the server, or just to restart it. And effects
#     the message issued to players on a server.
manager_stop_all_servers() {
	# An array of true/false for each server
	local was_running
	# False if no servers were running at all
	local any_running="false"
	
	# For all running servers issue the stop warning
	local max_countdown=0
	
	for ((server=0; server<${num_servers}; server++)); do
		if server_is_running "$server"; then
			any_running="true"
			was_running[$server]="true"
			STOP_COUNTDOWN[$server]="true"
			if [[ "${SERVER_STOP_DELAY[$i]}" -gt "$max_countdown" ]]; then
				max_countdown="${SERVER_STOP_DELAY[$server]}"
			fi
			
			# Send a warning message to the server
			case "$1" in
				stop) server_eval "$server" "say ${SERVER_STOP_MESSAGE[$server]}";;
				restart) server_eval "$server" "say ${SERVER_RESTART_MESSAGE[$server]}";;
			esac
			
			# Send message to stdout
			echo "Server \"${SERVER_NAME[$server]}\" was running, now stopping:"
			
			case "$1" in
				stop) echo "    Issued the warning \"${SERVER_STOP_MESSAGE[$server]}\" to players.";;
				restart) echo "    Issued the warning \"${SERVER_RESTART_MESSAGE[$server]}\" to players.";;
			esac
			
			case "${SERVER_STOP_DELAY[$server]}" in
				0) echo "    Stopping without delay.";;
				1) echo "    Stopping after 1 second.";;
				*) echo "    Stopping after ${SERVER_STOP_DELAY[$server]} seconds.";;
			esac
		else
			echo "Server \"${SERVER_NAME[$server]}\" was NOT running."
			was_running[$server]="false"
		fi
	done
	
	if "$any_running"; then
		# Wait for the maximum possible delay, stopping servers
		# at the correct times
		echo -n "All servers will have been issued the stop command... "
		for ((tick="${max_countdown}"; tick>=0; tick--)); do
			tput sc # Save cursor position
		
			if [[ "$tick" -le 1 ]]; then
				echo -n "in $tick second."
			else
				echo -n "in $tick seconds."
			fi
		
			# Each second check all server, to see if its their time to
			# stop. If so issue the stop command, and don't hang.
			for ((server=0; server<${num_servers}; server++)); do
				if server_is_running "$server"; then
					stop_tick="$(( ${max_countdown} - ${SERVER_STOP_DELAY[$server]} ))"
					if [[ "$stop_tick" == "$tick" ]]; then
						server_eval "$server" "stop"
						STOP_COUNTDOWN[$server]="false"
					fi
				fi
			done
		
			if [[ "$tick" > 0 ]]; then
				sleep 1
			fi

			tput rc # Restore cursor to position of last `sc'
			tput el # Clear to end of line
		done
	
		# Start a new line
		echo "Now."
	
		# Finally check all servers have stopped
		for ((server=0; server<${num_servers}; server++)); do
			if "${was_running[$server]}"; then
				echo -n "Ensuring server \"${SERVER_NAME[$server]}\" has stopped... "
				server_wait_for_stop "$server"
				echo "Done."
			fi
		done
	else
		echo "No servers were running."
	fi
}

# Stops all running servers without delay
manager_stop_all_servers_now() {
	# An array of true/false for each server
	local was_running
	# False if no servers were running at all
	local any_running="false"
	
	# Stop all servers at the same time
	for ((server=0; server<${num_servers}; server++)); do
		if server_is_running "$server"; then
			was_running[$server]="true"
			any_running="true"
			echo "Server \"${SERVER_NAME[$server]}\" was running, now stopping."
			server_eval "$server" "stop"
		else
			echo "Server \"${SERVER_NAME[$server]}\" was NOT running."
			was_running[$server]="false"
		fi
	done
	
	if "$any_running"; then
		# Ensure all the servers have stopped
		for ((server=0; server<${num_servers}; server++)); do
			if "${was_running[$server]}"; then
				echo -n "Ensuring server \"${SERVER_NAME[$server]}\" has stopped... "
				server_wait_for_stop "$server"
				echo "Done."
			fi
		done
	else
		echo "No servers were running."
	fi
}


### Command Functions

# Starts all servers
command_start() {
	# Required start option, for debian init.d scripts
	for ((server=0; server<${num_servers}; server++)); do
		# Only starts active servers
		if "${SERVER_ACTIVE[$server]}"; then
			if server_is_running "$server"; then
				echo "[ACTIVE] Server \"${SERVER_NAME[$server]}\" already started."
			else
				echo "[ACTIVE] Server \"${SERVER_NAME[$server]}\" starting:"
				server_start "$server"
			fi
		else
			if server_is_running "$server"; then
				echo "[INACTIVE] Server \"${SERVER_NAME[$server]}\" already started. It should not be running! Use \"$0 ${SERVER_NAME[$server]} stop\" to stop this server."
			else
				echo "[INACTIVE] Server \"${SERVER_NAME[$server]}\" leaving stopped, as this server is inactive."
			fi
		fi
	done
}

# Stops all servers after a delay
command_stop() {
	manager_stop_all_servers "stop"
}

# Stops all servers without delay
command_stop_now() {
	manager_stop_all_servers_now
}

# Restarts all servers
command_restart() {
	echo "Stopping servers:"
	command_stop
	
	echo "Starting servers:"
	command_start
}

# Restarts all servers without delay
command_restart_now() {
	echo "Stopping servers:"
	command_stop_now
	
	echo "Starting servers:"
	command_start
}

# Displays the MSM version
command_version() {
	local version="$VERSION"

	if [ "${version:0:1}" -eq 0 ]; then
		version="$version Beta"
	fi

	echo "Minecraft Server Manager $version"
}

# Displays a list of servers
command_server_list() {
	server_list
}

# Creates a new server with name $1
# $1: The new (valid) server name
command_server_create() {
	server_create "$1"
}

# Deletes an existing server with name $1
# $1: The name of the existing server
command_server_delete() {
	server_delete "$1"
}

# Renames an existing server
# $1: The existing server name
# $2: The new (valid) server name
command_server_rename() {
	server_rename "$1" "$2"
}

# Displays a list of all jar's in jar groups
command_jargroup_list() {
	jargroup_list
}

# Creates a new jar group
# $1: The new (valid) jar group name
# $2: The URL to use as the jar group target
command_jargroup_create() {
	jargroup_create "$1" "$2"
}

# Deletes and existing jar group
# $1: The name of a jar group to delete
command_jargroup_delete() {
	jargroup_delete "$1"
}

# Renames an existing jar group
# $1: The name of the existing jar group
# $2: The new (valid) name for the jar group
command_jargroup_rename() {
	jargroup_rename "$1" "$2"
}

# Changes a jar group's target url for automatic downloads
# $1: The jar group name
# $2: The new URL to use
command_jargroup_changetarget() {
	jargroup_settarget "$1" "$2"
}

# Downloads the latest jar for a jar group
# $1: The name of the jar group
command_jargroup_getlatest() {
	jargroup_getlatest "$1"
}

# Displays a list of possible commands and help strings
command_help() {
	# Outputs a list of all commands
	echo -e "Usage: $0 command:"
	echo -e
	echo -e "--Setup Commands------------------------------------------------"
	echo -e "  server list                                   List servers"
	echo -e "  server create <name>                          Creates a new Minecraft server"
	echo -e "  server delete <name>                          Deletes an existing Minecraft server"
	echo -e "  server rename <name> <new-name>               Renames an existing Minecraft server"
	echo -e
	echo -e "--Server Mangement Commands-------------------------------------"
	echo -e "  <server> start                                Starts a server"
	echo -e "  <server> stop [now]                           Stops a server after warning players, or right now"
	echo -e "  <server> restart [now]                        Restarts a server after warning players, or right now"
	echo -e "  <server> status                               Show the running/stopped status of a server"
	echo -e "  <server> connected                            List a servers connected players"
	echo -e "  <server> worlds list                          Lists the worlds a server has"
	echo -e "  <server> worlds load                          Creates links to worlds in storage for a server"
	echo -e "  <server> worlds ram <world>                   Toggles a world's \"in RAM\" status"
	echo -e "  <server> worlds todisk                        Synchronises any \"in RAM\" worlds to disk a server has"
	echo -e "  <server> worlds backup                        Makes a backup of all worlds a server has"
	echo -e "  <server> worlds on|off <world>                Activate or deactivate a world, inactive worlds are not backed up"
	echo -e "  <server> logroll                              Move a server log to a gziped archive, to reduce lag"
	echo -e "  <server> backup                               Makes a backup of an entire server directory"
	echo -e "  <server> jar <jargroup> [<file>]              Sets a server's jar file"
	echo -e
	echo -e "--Server Pass Through Commands----------------------------------"
	echo -e "  <server> wl on|off                            Enables/disables server whitelist checking"
	echo -e "  <server> wl add|remove <player>               Add/remove a player to/from a server's whitelist"
	echo -e "  <server> wl list                              List the players whitelisted for a server"
	echo -e "  <server> bl player add|remove <player>        Ban/pardon a player from/for a server"
	echo -e "  <server> bl ip add|remove <ip address>        Ban/pardon an IP address from/for a server"
	echo -e "  <server> bl list                              Lists the banned players and IP address for a server"
	echo -e "  <server> op add|remove <player>               Add/remove operator status for a player on a server"
	echo -e "  <server> op list                              Lists the operator players for a server"
	echo -e "  <server> gm survival|creative <player>        Change the game mode for a player on a server"
	echo -e "  <server> kick <player>                        Forcibly disconnect a player from a server"
	echo -e "  <server> say <message>                        Broadcast a (pink) message to all players on a server"
	echo -e "  <server> time set|add <number>                Set/increment time on a server (0-24000)"
	echo -e "  <server> toggledownfall                       Toggles rain and snow on a server"
	echo -e "  <server> give <player> <item> [amount] [data] Gives an entity to a player"
	echo -e "  <server> xp <player> <amount>                 Gives XP to, or takes away (when negative) XP from, a player"
	echo -e "  <server> save on|off                          Enable/disable writing world changes to file"
	echo -e "  <server> save all                             Force the writing of all non-saved world changes to file"
	echo -e "  <server> cmd <command>                        Send a command string to the server and return"
	echo -e "  <server> cmdlog <command>                     Same as 'cmd' but shows log output afterwards (Ctrl+C to exit)"
	echo -e "  <server> console                              Connects to the interactive console. Access may be limited"
	echo -e
	echo -e "--Jar Commands--------------------------------------------------"
	echo -e "  jargroup list                                 List the stored jar files."
	echo -e "  jargroup create <name> <download-url>         Create a new jar group, with a URL for new downloads"
	echo -e "  jargroup delete <name>                        Delete a jar group"
	echo -e "  jargroup rename <name> <new-name>             Rename a jar group"
	echo -e "  jargroup changeurl <name> <download-url>      Change the download URL for a jar group"
	echo -e "  jargroup getlatest <name>                     Download the latest jar file for a jar group"
	echo -e
	echo -e "--Global Commands-----------------------------------------------"
	echo -e "  start                                         Starts all active servers"
	echo -e "  stop [now]                                    Stops all running servers"
	echo -e "  restart [now]                                 Restarts all active servers"
	echo -e "  version                                       Prints the Minecraft Server Manager version installed"
}

# Starts an individual server
# $1: The server ID
command_server_start() {
	server_set_active "$1" "active"
	server_start "$1"
}

# Stops an individual server after a delay
# $1: The server ID
command_server_stop() {
	server_set_active "$1" "inactive"
	server_stop "$1"
}

# Stops an individual server without delay
# $1: The server ID
command_server_stop_now() {
	server_set_active "$1" "inactive"
	server_stop_now "$1"
}

# Restarts an individual server after a delay
# $1: The server ID
command_server_restart() {
	server_set_active "$1" "active"
	server_restart "$1"
}

# Restarts an individual server without delay
# $1: The server ID
command_server_restart_now() {
	server_set_active "$1" "active"
	server_restart_now "$1"
}

# Displays the running/stopped status of an individual server
# $1: The server ID
command_server_status() {
	if server_is_running "$1"; then
		echo "Server \"${SERVER_NAME[$1]}\" is running."
	else
		echo "Server \"${SERVER_NAME[$1]}\" is stopped."
	fi
}

# Displays a list of connected players for an individual server
# $1: The server ID
command_server_connected() {
	server_connected "$1"
}

# Displays a list of worlds for an individual server
# $1: The server ID
command_server_worlds_list() {
	server_worlds_list "$1"
}

# Creates symlinks for all active worlds so they can be used by the Minecraft
# server when running
# $1: The server ID
command_server_worlds_load() {
	server_ensure_links "$1"
}

# Toggles a world's inram status
# $1: The server ID
# $2: The world ID
command_server_worlds_ram() {
	if server_is_running "$1"; then
		error_exit SERVER_RUNNING "Server \"${SERVER_NAME[$1]}\" is running. Please stop the server before altering a worlds in-ram status."
	else
		world_toggle_ramdisk_state "$2"
	fi
}

# Synchronises all inram worlds back to disk for an individual server
# $1: The server ID
command_server_worlds_todisk() {
	server_save_off "$1"
	server_save_all "$1"
	server_worlds_to_disk "$1"
	server_save_on "$1"
}

# Makes a backup of all worlds for an individual server
# $1: The server ID
command_server_worlds_backup() {
	if server_is_running "$1"; then
		server_eval "$1" "say ${SERVER_WORLD_BACKUP_STARTED[$1]}"
		server_save_off "$1"
		server_save_all "$1"
	fi

	server_worlds_to_disk "$1"
	server_worlds_backup "$1"

	if server_is_running "$1"; then
		server_save_on "$1"
		server_eval "$1" "say ${SERVER_WORLD_BACKUP_FINISHED[$1]}"
	fi

	echo "Backup took $SECONDS seconds".
}

# Enables a world to be used by its server
# $1: The server ID
# $2: The world ID
command_server_worlds_on() {
	world_activate "$2"
}

# Disables a world from being used by its server, also prevents it from being
# backed up with the other worlds.
# $1: The server ID
# $2: The world ID
command_server_worlds_off() {
	world_deactivate "$2"
}

# Moves an individual server's log text to another file, leaving it empty
# $1: The server ID
command_server_logroll() {
	server_log_roll "$1"
}

# Makes a backup of an entire server directory
# $1: The server ID
command_server_backup() {
	if server_is_running "$1"; then
		server_eval "$1" "say ${SERVER_COMPLETE_BACKUP_STARTED[$1]}"
		server_save_off "$1"
		server_save_all "$1"
	fi

	server_worlds_to_disk "$1"
	server_backup "$1"

	if server_is_running "$1"; then
		server_save_on "$1"
		server_eval "$1" "say ${SERVER_COMPLETE_BACKUP_FINISHED[$1]}"
	fi

	echo "Backup took $SECONDS seconds".
}

# Sets an individual server's jar file to use when starting up
# $1: The server ID
# $2: The jar group name
# $3: Optionally a specific jar file name which exists within that jargroup, if
#     not provided the latest version will be used.
command_server_jar() {
	server_set_jar "$1" "$2" "$3"
}

# Turns a server's whitelist protection on
# $1: The server ID
command_server_whitelist_on() {
	if server_is_running "$1"; then
		server_eval "$1" "whitelist on"
		echo "Whitelist enabled"
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Turns a server's whitelist protection off
# $1: The server ID
command_server_whitelist_off() {
	if server_is_running "$1"; then
		server_eval "$1" "whitelist off"
		echo "Whitelist disabled"
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Adds a player name to a server's whitelist
# $1: The server ID
# $2: The player name
command_server_whitelist_add() {
	# TODO: Support whitelisting multiple players (see blacklist player add)
	if server_is_running "$1"; then
		server_eval "$1" "whitelist add $2"
		echo "Added \"$2\" to the whitelist."
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Removes a player name from a server's whitelist
# $1: The server ID
# $2: The player name
command_server_whitelist_remove() {
	# TODO: Support multiple player names
	if server_is_running "$1"; then
		server_eval "$1" "whitelist remove $2"
		echo "Removed \"$2\" from the whitelist."
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Displays a list of whitelisted players for an individual server
# $1: The server ID
command_server_whitelist_list() {
	if [ -f "${SERVER_WHITELIST[$1]}" ]; then
		local players="$(cat "${SERVER_WHITELIST[$1]}")"

		if [ -z "$players" ]; then
			echo "No players are whitelisted."
		else
			echo "$players"
		fi
	else
		echo "No players are whitelisted."
	fi
}

# Adds player names to a server's ban list
# $1: The server ID
# $2->: The player names
command_server_blacklist_player_add() {
	for player in "${@:2}"; do
	 	server_eval "$1" "ban $player"
	done
	
	if [[ $# -gt 2 ]]; then
		echo -n "Blacklisted the following players: "
		echo -n "$2"
		for player in "${@:3}"; do
		 	echo -n ", $player"
		done
		echo "."
	else
		echo "Blacklisted \"$2\"."
	fi
}

# Removes player names from a server's ban list
# $1: The server ID
# $2->: The player names
command_server_blacklist_player_remove() {
	for player in "${@:2}"; do
	 	server_eval "$1" "pardon $player"
	done
	
	if [[ $# -gt 2 ]]; then
		echo -n "Removed the following players from the blacklist: "
		echo -n "$2"
		for player in "${@:3}"; do
		 	echo -n ", $player"
		done
		echo "."
	else
		echo "Removed \"$2\" from the blacklist."
	fi
}

# Adds ip addresses to a server's ban list
# $1: The server ID
# $2->: The ip addresses
command_server_blacklist_ip_add() {
	for address in "${@:2}"; do
	 	server_eval "$1" "ban-ip $address"
	done
	
	if [[ $# -gt 2 ]]; then
		echo -n "Blacklisted the following ip addresses: "
		echo -n "$2"
		for player in "${@:3}"; do
		 	echo -n ", $address"
		done
		echo "."
	else
		echo "Blacklisted \"$2\"."
	fi
}

# Removes ip addresses to a server's ban list
# $1: The server ID
# $2->: The ip addresses
command_server_blacklist_ip_remove() {
	for address in "${@:2}"; do
	 	server_eval "$1" "pardon-ip $address"
	done
	
	if [[ $# -gt 2 ]]; then
		echo -n "Removed the following ip addresses from the blacklist: "
		echo -n "$2"
		for player in "${@:3}"; do
		 	echo -n ", $address"
		done
		echo "."
	else
		echo "Removed \"$2\" from the ip blacklist."
	fi
}

# Displays a server's banned player names and ip addresses
# $1: The server ID
command_server_blacklist_list() {
	local players
	local ips

	if [ -f "${SERVER_BANNED_PLAYERS[$1]}" ]; then
		players="$(cat "${SERVER_BANNED_PLAYERS[$1]}")"
	fi

	if [ -f "${SERVER_BANNED_IPS[$1]}" ]; then
		ips="$(cat "${SERVER_BANNED_IPS[$1]}")"
	fi

	if [[ -z "$players" && -z "$ips" ]]; then
		echo "The blacklist is empty."
	else
		if [[ ! -z "$players" ]]; then
			echo "Players:"
			for name in $players; do
				echo "    $name"
			done
		fi

		if [[ ! -z "$ips" ]]; then
			echo "IP Addresses:"
			for address in $ips; do
				echo "    $address"
			done
		fi
	fi
}

# Adds a player name to a server's list of operators
# $1: The server ID
# $2: The player name
command_server_operator_add() {
	# TODO: Support multiple player names
	if server_is_running "$1"; then
		server_eval "$1" "op $2"
		echo "The player \"$2\" is now an operator for the server."
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Removes a player name to a server's list of operators
# $1: The server ID
# $2: The player name
command_server_operator_remove() {
	# TODO: Support multiple player names
	if server_is_running "$1"; then
		server_eval "$1" "deop $2"
		echo "The player \"$2\" is no longer an operator for the server."
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Displays a list of operators for an individual server
# $1: The server ID
command_server_operator_list() {
	# TODO: Protect against non-existent files
	local players="$(cat "${SERVER_OPS[$1]}")"

	if [ -z "$players" ]; then
		echo "No players are operators."
	else
		echo "$players"
	fi
}

# Sets the game mode for
# $1: The server ID
# $2: The game mode
# $3: The player name
command_server_gamemode() {
	# TODO: Support multiple player names
	if server_is_running "$1"; then
		local mode line regex
		case "$2" in
			creative|1) mode=1;;
			survival|0) mode=0;;
			*) error_exit INVALID_ARGUMENT "Invalid gamemode type \"$2\" options are \"survival\", \"creative\", \"0\" or \"1\".";;
		esac

		line="$(server_eval_and_get_line "$1" "gamemode $3 $mode" "${SERVER_CONFIRM_GAMEMODE[$1]}" "${SERVER_CONFIRM_GAMEMODE_FAIL_NO_USER[$1]}" "${SERVER_CONFIRM_GAMEMODE_FAIL_NO_CHANGE[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_GAMEMODE[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "Changed game mode of \"$3\" to \"$2\"."
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_GAMEMODE_FAIL_NO_USER[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "The player \"$3\" was not found to be logged on."
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_GAMEMODE_FAIL_NO_CHANGE[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "The player \"$3\" was already in mode \"$2\"."
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Kicks a connected player from a server
# $1: The server ID
# $2: The player name
command_server_kick() {
	# TODO: Support multiple player names
	if server_is_running "$1"; then
		local line regex
		line="$(server_eval_and_get_line "$1" "kick $2" "${SERVER_CONFIRM_KICK[$1]}" "${SERVER_CONFIRM_KICK_FAIL[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_KICK[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "Kicked \"$2\" from game."
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_KICK_FAIL[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "The player \"$2\" is not connected."
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Broadcasts a message to all connected players for a server
# $1: The server ID
# $2->: Words of the message, will be concatinated with spaces
command_server_say() {
	if server_is_running "$1"; then
		server_eval "$1" "say ${*:2}"
		echo "Message sent to players."
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Sets the time on an individual server
# $1: The server ID
# $2: The time
command_server_time_set() {
	if server_is_running "$1"; then
		local line regex
		line="$(server_eval_and_get_line "$1" "time set $2" "${SERVER_CONFIRM_TIME_SET[$1]}" "${SERVER_CONFIRM_TIME_SET_FAIL[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_TIME_SET[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "Set time to \"$2\"."
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_TIME_SET_FAIL[$1]}"
		if [[ "$line" =~ $regex ]]; then
			error_exit INVALID_ARGUMENT "Unable to convert \"$2\" to a time."
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Increments the time on an individual server
# $1: The server ID
# $2: The time to add
command_server_time_add() {
	if server_is_running "$1"; then
		local line regex
		line="$(server_eval_and_get_line "$1" "time add $2" "${SERVER_CONFIRM_TIME_ADD[$1]}" "${SERVER_CONFIRM_TIME_ADD_FAIL[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_TIME_ADD[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "Added \"$2\" to time."
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_TIME_ADD_FAIL[$1]}"
		if [[ "$line" =~ $regex ]]; then
			error_exit INVALID_ARGUMENT "Unable to convert \"$2\" to a time."
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Toggles the downfall of rain and snow on an individual server
# $1: The server ID
command_server_toggledownfall() {
	if server_is_running "$1"; then
		local line regex
		line="$(server_eval_and_get_line "$1" "toggledownfall" "${SERVER_CONFIRM_TOGGLEDOWNFALL[$1]}" "${SERVER_CONFIRM_TOGGLEDOWNFALL_FAIL[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_TOGGLEDOWNFALL[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:36}"
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_TOGGLEDOWNFALL_FAIL[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:34}"
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Gives entities to players in game
# $1: The server ID
# $2: The player name
# $3: The entity id/name
# $4: The amount to give
# $5: The entity damage value
command_server_give() {
	if server_is_running "$1"; then
		local line regex

		if [[ "$3" =~ ^\-[0-9]+$ ]]; then
			error_exit INVALID_ARGUMENT "Item ID \"$3\" must be a positive integer or string."
		fi

		line="$(server_eval_and_get_line "$1" "give $2 $3 $4 $5" "${SERVER_CONFIRM_GIVE[$1]}" "${SERVER_CONFIRM_GIVE_FAIL_NO_USER[$1]}" "${SERVER_CONFIRM_GIVE_FAIL_NO_ITEM[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_GIVE[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:36}"
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_GIVE_FAIL_NO_USER[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:27}"
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_GIVE_FAIL_NO_ITEM[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:27}"
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Gives XP to a player in game
# $1: The server ID
# $2: The player name
# $3: The amount of XP to give (can be negative)
command_server_xp() {
	if server_is_running "$1"; then
		local line regex
		line="$(server_eval_and_get_line "$1" "xp $2 $3" "${SERVER_CONFIRM_XP[$1]}" "${SERVER_CONFIRM_XP_FAIL_NO_USER[$1]}" "${SERVER_CONFIRM_XP_FAIL_INVALID_AMOUNT[$1]}")"

		regex="${LOG_REGEX} ${SERVER_CONFIRM_XP[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:36}"
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_XP_FAIL_NO_USER[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:27}"
		fi
		regex="${LOG_REGEX} ${SERVER_CONFIRM_XP_FAIL_INVALID_AMOUNT[$1]}"
		if [[ "$line" =~ $regex ]]; then
			echo "${line:27}"
		fi
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Turns world saving on for an individual server
# $1: The server ID
command_server_save_on() {
	server_save_on "$1"
}

# Turns world saving off for an individual server
# $1: The server ID
command_server_save_off() {
	server_save_off "$1"
}

# Forces the saving of all pending world saves
# $1: The server ID
command_server_save_all() {
	server_save_all "$1"
}

# Sends a command string to the server to be executed
# $1: The server ID
# $2->: A command, separate arguments are concatinated with spaces
command_server_cmd() {
	if server_is_running "$1"; then
		server_eval "$1" "${*:2}"
		echo "Command sent."
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Sends a command string to the server to be executed, and then tails the
# server logs to watch fro results.
# $1: The server ID
# $2->: A command, separate arguments are concatinated with spaces
command_server_cmdlog() {
	if server_is_running "$1"; then
		server_eval "$1" "${*:2}"
		echo "Now watching logs (press Ctrl+C to exit):"
		as_user "${SERVER_USER_NAME[$1]}" "tail --pid=$$ --follow --lines=0 --sleep-interval=0.1 ${SERVER_LOG[$1]}"
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}

# Resumes a server's screen session (requires ssh-ed in as server user, using
# the `su` command will not work.)
# $1: The server ID
command_server_console() {
	if server_is_running "$1"; then
		as_user "${SERVER_USER_NAME[$1]}" "screen -r ${SERVER_SCREEN_NAME[$1]}"
	else
		error_exit SERVER_STOPPED "Server \"${SERVER_NAME[$1]}\" is not running."
	fi
}


### Main Functions

# Initialises a server's world
# $1: The server id
# $2: The world id to use
# $3: The name of the world
server_world_init() {
	WORLD_SERVER_ID[$2]="$1"
	WORLD_NAME[$2]="$3"
	WORLD_ACTIVE_PATH[$2]="${SERVER_WORLD_STORAGE[$1]}/${WORLD_NAME[$2]}"
	WORLD_INACTIVE_PATH[$2]="${SERVER_WORLD_STORAGE_INACTIVE[$1]}/${WORLD_NAME[$2]}"
	
	# Set the status of this world (active/inactive)
	if [ -d "${WORLD_ACTIVE_PATH[$2]}" ]; then
		WORLD_STATUS[$2]="active"
		WORLD_PATH[$2]="${WORLD_ACTIVE_PATH[$2]}"
	else
		if [ -d "${WORLD_INACTIVE_PATH[$2]}" ]; then
			WORLD_STATUS[$2]="inactive"
			WORLD_PATH[$2]="${WORLD_INACTIVE_PATH[$2]}"
		else
			WORLD_STATUS[$2]="unknown"
			
			error_exit NAME_NOT_FOUND "World cannot be found in either \"${WORLD_ACTIVE_PATH[$2]}\" or \"${WORLD_INACTIVE_PATH[$2]}\"."
		fi
	fi
	
	# TODO: Allow the inram flag location to be overridable.
	WORLD_FLAG_INRAM[$2]="${WORLD_PATH[$2]}/inram"
	WORLD_LINK[$2]="${SERVER_PATH[$1]}/${WORLD_NAME[$2]}"
	WORLD_BACKUP_PATH[$2]="$WORLD_ARCHIVE_PATH/${SERVER_NAME[$1]}/${WORLD_NAME[$2]}"

	# If the ramdisk path is set, get the path for this world
	if [ ! -z "$RAMDISK_STORAGE_PATH" ]; then
		WORLD_RAMDISK_PATH[$2]="${RAMDISK_STORAGE_PATH}/${SERVER_NAME[$1]}/${WORLD_NAME[$2]}"
	fi

	# Detect whether this world should be in ram
	if [[ -e "${WORLD_FLAG_INRAM[$2]}" ]]; then
		WORLD_INRAM[$2]="true"
	else
		WORLD_INRAM[$2]="false"
	fi
}

# Load a config file for a server
# $1: The id of the server to laod
server_load_config() {
	local name value
	
	if [[ -f "${SERVER_CONF[$1]}" ]]; then
		while read line; do 
		 	# ignore comment lines
			echo "$line" | grep "^#" >/dev/null 2>&1 && continue

		   	# if not empty, set the property using declare
		   	if [ ! -z "$line" ]; then
			 	name="$(echo $line | awk -F '=' '{print $1}')"
				value="$(echo $line | awk -F '=' '{print $2}')"
			fi

			case "$name" in
				# Minecraft settings:
				allow-flight) SERVER_PROPERTIES_ALLOW_FLIGHT="$value";;
				allow-nether) SERVER_PROPERTIES_ALLOW_NETHER="$value";;
				difficulty) SERVER_PROPERTIES_DIFFICULTY="$value";;
				enable-query) SERVER_PROPERTIES_ENABLE_QUERY="$value";;
				enable-rcon) SERVER_PROPERTIES_ENABLE_RCON="$value";;
				gamemode) SERVER_PROPERTIES_GAMEMODE="$value";;
				generate-structures) SERVER_PROPERTIES_GENERATE_STRUCTURES="$value";;
				level-name) SERVER_PROPERTIES_LEVEL_NAME="$value";;
				level-seed) SERVER_PROPERTIES_LEVEL_SEED="$value";;
				level-type) SERVER_PROPERTIES_LEVEL_TYPE="$value";;
				max-build-height) SERVER_PROPERTIES_MAX_BUILD_HEIGHT="$value";;
				max-players) SERVER_PROPERTIES_MAX_PLAYERS="$value";;
				motd) SERVER_PROPERTIES_MOTD="$value";;
				texture-pack) SERVER_PROPERTIES_TEXTURE_PACK="$value";;
				online-mode) SERVER_PROPERTIES_ONLINE_MODE="$value";;
				pvp) SERVER_PROPERTIES_PVP="$value";;
				query.port) SERVER_PROPERTIES_QUERY_PORT="$value";;
				rcon.password) SERVER_PROPERTIES_RCON_PASSWORD="$value";;
				rcon.port) SERVER_PROPERTIES_RCON_PORT="$value";;
				server-ip) SERVER_PROPERTIES_SERVER_IP="$value";;
				server-port) SERVER_PROPERTIES_SERVER_PORT="$value";;
				spawn-animals) SERVER_PROPERTIES_SPAWN_ANIMALS="$value";;
				spawn-monsters) SERVER_PROPERTIES_SPAWN_MONSTERS="$value";;
				spawn-npcs) SERVER_PROPERTIES_SPAWN_NPCS="$value";;
				view-distance) SERVER_PROPERTIES_VIEW_DISTANCE="$value";;
				white-list) SERVER_PROPERTIES_WHITE_LIST="$value";;

				# MSM setttings:
				msm-server-user) SERVER_USER_NAME[$1]="$value";;
				msm-screen-name) SERVER_SCREEN_NAME[$1]="$value";;
				msm-world-storage-path) SERVER_WORLD_STORAGE[$1]="${SERVER_PATH[$1]}/$value";;
				msm-world-storage-inactive-path) SERVER_WORLD_STORAGE_INACTIVE[$1]="${SERVER_PATH[$1]}/$value";;

				msm-log) SERVER_LOG[$1]="${SERVER_PATH[$1]}/$value";;
				msm-whitelist) SERVER_WHITELIST[$1]="${SERVER_PATH[$1]}/$value";;
				msm-banned-players) SERVER_BANNED_PLAYERS[$1]="${SERVER_PATH[$1]}/$value";;
				msm-banned-ips) SERVER_BANNED_IPS[$1]="${SERVER_PATH[$1]}/$value";;

				msm-ops) SERVER_OPS[$1]="${SERVER_PATH[$1]}/$value";;
				msm-jar) SERVER_JAR[$1]="${SERVER_PATH[$1]}/$value";;
				msm-ram) SERVER_RAM[$1]="$value";;
				msm-invocation) SERVER_INVOCATION[$1]="$value";;

				msm-stop-delay) SERVER_STOP_DELAY[$1]="$value";;
				msm-restart-delay) SERVER_RESTART_DELAY[$1]="$value";;
				
				msm-stop-message) SERVER_STOP_MESSAGE[$1]="$value";;
				msm-stop-abort) SERVER_STOP_ABORT[$1]="$value";;
				msm-restart-message) SERVER_RESTART_MESSAGE[$1]="$value";;
				msm-restart-abort) SERVER_RESTART_ABORT[$1]="$value";;
				msm-world-backup-started) SERVER_WORLD_BACKUP_STARTED[$1]="$value";;
				msm-world-backup-finished) SERVER_WORLD_BACKUP_FINISHED[$1]="$value";;
				msm-complete-backup-started) SERVER_COMPLETE_BACKUP_STARTED[$1]="$value";;
				msm-complete-backup-finished) SERVER_COMPLETE_BACKUP_FINISHED[$1]="$value";;
				msm-complete-backup-follow-symlinks) SERVER_COMPLETE_BACKUP_FOLLOW_SYMLINKS[$1]="$value";;

				msm-confirm-save-on) SERVER_CONFIRM_SAVE_ON[$1]="$value";;
				msm-confirm-save-off) SERVER_CONFIRM_SAVE_OFF[$1]="$value";;
				msm-confirm-save-all) SERVER_CONFIRM_SAVE_ALL[$1]="$value";;
				msm-confirm-start) SERVER_CONFIRM_START[$1]="$value";;
				msm-confirm-whitelist-list) SERVER_CONFIRM_WHITELIST_LIST[$1]="$value";;
				msm-confirm-kick) SERVER_CONFIRM_CONFIRM_KICK[$1]="$value";;
				msm-confirm-kick-fail) SERVER_CONFIRM_KICK_FAIL[$1]="$value";;
				msm-confirm-time-set) SERVER_CONFIRM_TIME_SET[$1]="$value";;
				msm-confirm-time-set-fail) SERVER_CONFIRM_TIME_SET_FAIL[$1]="$value";;
				msm-confirm-time-add) SERVER_CONFIRM_TIME_ADD[$1]="$value";;
				msm-confirm-time-add-fail) SERVER_CONFIRM_TIME_ADD_FAIL[$1]="$value";;
				msm-confirm-toggledownfall) SERVER_CONFIRM_TOGGLEDOWNFALL[$1]="$value";;
				msm-confirm-toggledownfall-fail) SERVER_CONFIRM_TOGGLEDOWNFALL_FAIL[$1]="$value";;
				msm-confirm-gamemode) SERVER_CONFIRM_GAMEMODE[$1]="$value";;
				msm-confirm-gamemode-fail-no-user) SERVER_CONFIRM_GAMEMODE_FAIL_NO_USER[$1]="$value";;
				msm-confirm-gamemode-fail-no-change) SERVER_CONFIRM_GAMEMODE_FAIL_NO_CHANGE[$1]="$value";;
				msm-confirm-give) SERVER_CONFIRM_GIVE[$1]="$value";;
				msm-confirm-give-fail-no-user) SERVER_CONFIRM_GIVE_FAIL_NO_USER[$1]="$value";;
				msm-confirm-give-fail-no-item) SERVER_CONFIRM_GIVE_FAIL_NO_ITEM[$1]="$value";;
				msm-confirm-xp) SERVER_CONFIRM_XP[$1]="$value";;
				msm-confirm-xp-fail-no-user) SERVER_CONFIRM_XP_FAIL_NO_USER[$1]="$value";;
				msm-confirm-xp-fail-invalid-amount) SERVER_CONFIRM_XP_FAIL_INVALID_AMOUNT[$1]="$value";;
			esac
		done < "${SERVER_CONF[$1]}"
	fi
}

# Initialise a server's variables
# $1: The id to use for this server
# $2: The name of the server
server_init() {
	SERVER_NAME[$1]="$2"
	SERVER_PATH[$1]="$SERVER_STORAGE_PATH/$2"
	SERVER_CONF[$1]="${SERVER_PATH[$1]}/$SERVER_CONF_NAME"
	SERVER_FLAG_ACTIVE[$1]="${SERVER_PATH[$1]}/active"
	SERVER_BACKUP_PATH[$1]="$BACKUP_ARCHIVE_PATH/${SERVER_NAME[$1]}"
	SERVER_LOG_archive_path[$1]="$LOG_ARCHIVE_PATH/${SERVER_NAME[$1]}"
	
	if [[ -e "${SERVER_FLAG_ACTIVE[$1]}" ]]; then
		SERVER_ACTIVE[$1]="true"
	else
		SERVER_ACTIVE[$1]="false"
	fi
	
	# Setup defaults
	# Note: screen_name will at this stage have the {SERVER_NAME} tag in it
	# which needs to be replaced.
	# Invocation may also the {RAM} and {JAR} tags.
	
	SERVER_USER_NAME[$1]="$DEFAULT_SERVER_USER"
	SERVER_SCREEN_NAME[$1]="${DEFAULT_SCREEN_NAME//\{SERVER_NAME\}/${SERVER_NAME[$1]}}" # Replace tags now, they cannot change
	SERVER_WORLD_STORAGE[$1]="${SERVER_PATH[$1]}/$DEFAULT_WORLD_STORAGE_PATH"
	SERVER_WORLD_STORAGE_INACTIVE[$1]="${SERVER_PATH[$1]}/$DEFAULT_WORLD_STORAGE_INACTIVE_PATH"
	SERVER_LOG[$1]="${SERVER_PATH[$1]}/$DEFAULT_LOG"
	SERVER_WHITELIST[$1]="${SERVER_PATH[$1]}/$DEFAULT_WHITELIST"
	SERVER_BANNED_PLAYERS[$1]="${SERVER_PATH[$1]}/$DEFAULT_BANNED_PLAYERS"
	SERVER_BANNED_IPS[$1]="${SERVER_PATH[$1]}/$DEFAULT_BANNED_IPS"
	SERVER_OPS[$1]="${SERVER_PATH[$1]}/$DEFAULT_OPS"
	SERVER_JAR[$1]="${SERVER_PATH[$1]}/$DEFAULT_JAR"
	SERVER_RAM[$1]="$DEFAULT_RAM"
	SERVER_INVOCATION[$1]="$DEFAULT_INVOCATION" # Don't replace tags yet, they may change
	SERVER_STOP_DELAY[$1]="$DEFAULT_STOP_DELAY"
	SERVER_RESTART_DELAY[$1]="$DEFAULT_RESTART_DELAY"
	SERVER_STOP_MESSAGE[$1]="$DEFAULT_STOP_MESSAGE"
	SERVER_STOP_ABORT[$1]="$DEFAULT_STOP_ABORT"
	SERVER_RESTART_MESSAGE[$1]="$DEFAULT_RESTART_MESSAGE"
	SERVER_RESTART_ABORT[$1]="$DEFAULT_RESTART_ABORT"
	SERVER_WORLD_BACKUP_STARTED[$1]="$DEFAULT_WORLD_BACKUP_STARTED"
	SERVER_WORLD_BACKUP_FINISHED[$1]="$DEFAULT_WORLD_BACKUP_FINISHED"
	SERVER_COMPLETE_BACKUP_STARTED[$1]="$DEFAULT_COMPLETE_BACKUP_STARTED"
	SERVER_COMPLETE_BACKUP_FINISHED[$1]="$DEFAULT_COMPLETE_BACKUP_FINISHED"
	SERVER_COMPLETE_BACKUP_FOLLOW_SYMLINKS[$1]="$DEFAULT_COMPLETE_BACKUP_FOLLOW_SYMLINKS"
	SERVER_CONFIRM_SAVE_ON[$1]="$DEFAULT_CONFIRM_SAVE_ON"
	SERVER_CONFIRM_SAVE_OFF[$1]="$DEFAULT_CONFIRM_SAVE_OFF"
	SERVER_CONFIRM_SAVE_ALL[$1]="$DEFAULT_CONFIRM_SAVE_ALL"
	SERVER_CONFIRM_START[$1]="$DEFAULT_CONFIRM_START"
	SERVER_CONFIRM_KICK[$1]="$DEFAULT_CONFIRM_KICK"
	SERVER_CONFIRM_KICK_FAIL[$1]="$DEFAULT_CONFIRM_KICK_FAIL"
	SERVER_CONFIRM_TIME_SET[$1]="$DEFAULT_CONFIRM_TIME_SET"
	SERVER_CONFIRM_TIME_SET_FAIL[$1]="$DEFAULT_CONFIRM_TIME_SET_FAIL"
	SERVER_CONFIRM_TIME_ADD[$1]="$DEFAULT_CONFIRM_TIME_ADD"
	SERVER_CONFIRM_TIME_ADD_FAIL[$1]="$DEFAULT_CONFIRM_TIME_ADD_FAIL"
	SERVER_CONFIRM_TOGGLEDOWNFALL[$1]="$DEFAULT_CONFIRM_TOGGLEDOWNFALL"
	SERVER_CONFIRM_TOGGLEDOWNFALL_FAIL[$1]="$DEFAULT_CONFIRM_TOGGLEDOWNFALL_FAIL"
	SERVER_CONFIRM_GAMEMODE[$1]="$DEFAULT_CONFIRM_GAMEMODE"
	SERVER_CONFIRM_GAMEMODE_FAIL_NO_USER[$1]="$DEFAULT_CONFIRM_GAMEMODE_FAIL_NO_USER"
	SERVER_CONFIRM_GAMEMODE_FAIL_NO_CHANGE[$1]="$DEFAULT_CONFIRM_GAMEMODE_FAIL_NO_CHANGE"
	SERVER_CONFIRM_GIVE[$1]="$DEFAULT_CONFIRM_GIVE"
	SERVER_CONFIRM_GIVE_FAIL_NO_USER[$1]="$DEFAULT_CONFIRM_GIVE_FAIL_NO_USER"
	SERVER_CONFIRM_GIVE_FAIL_NO_ITEM[$1]="$DEFAULT_CONFIRM_GIVE_FAIL_NO_ITEM"
	SERVER_CONFIRM_XP[$1]="$DEFAULT_CONFIRM_XP"
	SERVER_CONFIRM_XP_FAIL_NO_USER[$1]="$DEFAULT_CONFIRM_XP_FAIL_NO_USER"
	SERVER_CONFIRM_XP_FAIL_INVALID_AMOUNT[$1]="$DEFAULT_CONFIRM_XP_FAIL_INVALID_AMOUNT"
	
	
	# Load config overrides from server config file if present
	server_load_config "$1"
	
	
	# Replace tags in delay messages
	SERVER_STOP_MESSAGE[$1]="${SERVER_STOP_MESSAGE[$1]//\{DELAY\}/${SERVER_STOP_DELAY[$1]}}"
	SERVER_RESTART_MESSAGE[$1]="${SERVER_RESTART_MESSAGE[$1]//\{DELAY\}/${SERVER_RESTART_DELAY[$1]}}"
	
	# Replace tags in server invocation
	SERVER_INVOCATION[$1]="${SERVER_INVOCATION[$1]//\{RAM\}/${SERVER_RAM[$1]}}"
	SERVER_INVOCATION[$1]="${SERVER_INVOCATION[$1]//\{JAR\}/${SERVER_JAR[$1]}}"
	
	
	# Load worlds if there is a world storage directory present
	SERVER_WORLD_OFFSET[$1]=0
	SERVER_NUM_WORLDS[$1]=0
	
	# Start world id's for this server's worlds at the end of the array
	local id="$num_worlds"
	
	# Record the index at which worlds for this server start
	SERVER_WORLD_OFFSET[$1]="$id"
	
	if [[ -d "${SERVER_WORLD_STORAGE[$1]}" ]]; then
		# Load active worlds
		while IFS= read -r -d $'\0' path; do
			local name="$(basename "$path")"
			server_world_init "$1" "$id" "$name"
			
			# Build the server_worlds comma separated list
			if [[ "$id" == "${SERVER_WORLD_OFFSET[$1]}" ]]; then
				SERVER_WORLDS[$1]="$name"
			else
				SERVER_WORLDS[$1]="${SERVER_WORLDS[$1]}, $name"
			fi
			
			id="$(($id+1))"
			num_worlds="$id"
		done < <(find "${SERVER_WORLD_STORAGE[$1]}" -mindepth 1 -maxdepth 1 -type d -print0)
	fi
	
	if [[ -d "${SERVER_WORLD_STORAGE_INACTIVE[$1]}" ]]; then
		# Load inactive worlds
		while IFS= read -r -d $'\0' path; do
			local name="$(basename "$path")"
			server_world_init "$1" "$id" "$name"
			
			# Build the server_worlds_inactive comma separated list
			if [[ "$id" == "${SERVER_WORLD_OFFSET[$1]}" ]]; then
				SERVER_WORLDS[$1]="$name"
			else
				SERVER_WORLDS[$1]="${SERVER_WORLDS[$1]}, $name"
			fi
			
			id="$(($id+1))"
			num_worlds="$id"
		done < <(find "${SERVER_WORLD_STORAGE_INACTIVE[$1]}" -mindepth 1 -maxdepth 1 -type d -print0)
	fi
	
	# Record the number of worlds this server has
	SERVER_NUM_WORLDS[$1]="$(( $id - ${SERVER_WORLD_OFFSET[$1]} ))"
}

# Asserts that a variable has been set in the config file
# $1: The name of the variable to test
assert_is_set_in_config() {
    [[ ! ${!1} && ${!1-_} ]] && {
        error_exit CONF_ERROR "Have you recently upgraded? \"$1\" is a new required setting, and must be set in $CONF. See https://raw.github.com/marcuswhybrow/minecraft-server-manager/${VERSION}/msm.conf and look for the line starting with \"$1\". Add this line to your settings. Sorry about this... A better sollution for upgrading is being worked on."
    }
}

# Ensures all non-optional settings have been set
init_ensure_settings() {
	assert_is_set_in_config USERNAME
	assert_is_set_in_config SERVER_STORAGE_PATH
	assert_is_set_in_config JAR_STORAGE_PATH
	assert_is_set_in_config RAMDISK_STORAGE_PATH
	
	assert_is_set_in_config WORLD_ARCHIVE_PATH
	assert_is_set_in_config LOG_ARCHIVE_PATH
	assert_is_set_in_config BACKUP_ARCHIVE_PATH
	
	assert_is_set_in_config DEFAULT_SERVER_USER
	assert_is_set_in_config DEFAULT_SCREEN_NAME
	assert_is_set_in_config DEFAULT_WORLD_STORAGE_PATH
	assert_is_set_in_config DEFAULT_WORLD_STORAGE_INACTIVE_PATH
	assert_is_set_in_config DEFAULT_COMPLETE_BACKUP_FOLLOW_SYMLINKS
	
	assert_is_set_in_config DEFAULT_LOG
	assert_is_set_in_config DEFAULT_PROPERTIES
	assert_is_set_in_config DEFAULT_WHITELIST
	assert_is_set_in_config DEFAULT_BANNED_PLAYERS
	assert_is_set_in_config DEFAULT_BANNED_IPS
	assert_is_set_in_config DEFAULT_OPS

	assert_is_set_in_config DEFAULT_JAR
	assert_is_set_in_config DEFAULT_RAM
	assert_is_set_in_config DEFAULT_INVOCATION
	
	assert_is_set_in_config DEFAULT_STOP_DELAY
	assert_is_set_in_config DEFAULT_RESTART_DELAY
	assert_is_set_in_config DEFAULT_STOP_MESSAGE
	assert_is_set_in_config DEFAULT_STOP_ABORT
	assert_is_set_in_config DEFAULT_RESTART_MESSAGE
	assert_is_set_in_config DEFAULT_RESTART_ABORT
	assert_is_set_in_config DEFAULT_WORLD_BACKUP_STARTED
	assert_is_set_in_config DEFAULT_WORLD_BACKUP_FINISHED
	assert_is_set_in_config DEFAULT_COMPLETE_BACKUP_STARTED
	assert_is_set_in_config DEFAULT_COMPLETE_BACKUP_FINISHED
	assert_is_set_in_config DEFAULT_CONFIRM_SAVE_ON
	assert_is_set_in_config DEFAULT_CONFIRM_SAVE_OFF
	assert_is_set_in_config DEFAULT_CONFIRM_SAVE_ALL
	assert_is_set_in_config DEFAULT_CONFIRM_START
	assert_is_set_in_config DEFAULT_CONFIRM_KICK
	assert_is_set_in_config DEFAULT_CONFIRM_KICK_FAIL
	assert_is_set_in_config DEFAULT_CONFIRM_TIME_SET
	assert_is_set_in_config DEFAULT_CONFIRM_TIME_SET_FAIL
	assert_is_set_in_config DEFAULT_CONFIRM_TIME_ADD
	assert_is_set_in_config DEFAULT_CONFIRM_TIME_ADD_FAIL
	assert_is_set_in_config DEFAULT_CONFIRM_TOGGLEDOWNFALL
	assert_is_set_in_config DEFAULT_CONFIRM_TOGGLEDOWNFALL_FAIL
	assert_is_set_in_config DEFAULT_CONFIRM_GAMEMODE
	assert_is_set_in_config DEFAULT_CONFIRM_GAMEMODE_FAIL_NO_USER
	assert_is_set_in_config DEFAULT_CONFIRM_GAMEMODE_FAIL_NO_CHANGE
	assert_is_set_in_config DEFAULT_CONFIRM_GIVE
	assert_is_set_in_config DEFAULT_CONFIRM_GIVE_FAIL_NO_USER
	assert_is_set_in_config DEFAULT_CONFIRM_GIVE_FAIL_NO_ITEM
	assert_is_set_in_config DEFAULT_CONFIRM_XP
	assert_is_set_in_config DEFAULT_CONFIRM_XP_FAIL_NO_USER
	assert_is_set_in_config DEFAULT_CONFIRM_XP_FAIL_INVALID_AMOUNT
}

init() {
	# Sourcing $CONF will override the previous defaults, with new values
	source "$CONF"
	
	init_ensure_settings
	
	num_worlds=0
	num_servers=0
	
	if [ -d "$SERVER_STORAGE_PATH" ]; then
		local id=0
		while IFS= read -r -d $'\0' path; do
			local name="$(basename "$path")"
			server_init "$id" "$name"
			id="$(($id+1))"
			num_servers="$id"
		done < <(find "$SERVER_STORAGE_PATH" -mindepth 1 -maxdepth 1 -type d -print0)
	fi
}

# Called if the script is interrupted before exiting naturally
interrupt() {
	local exit_message="false"
	for ((i=0; $i<$num_servers; i++)); do
		if [[ "${STOP_COUNTDOWN[$i]}" == "true" ]] && server_is_running "$i"; then
			if [[ "$exit_message" == "false" ]]; then
				echo -e "\nInterrupted..."
				exit_message="true"
			fi
			server_eval "$i" "say ${SERVER_STOP_ABORT[$i]}"
			echo "Server \"${SERVER_NAME[$i]}\" shutdown was aborted."
		fi
		
		if [[ "${RESTART_COUNTDOWN[$i]}" == "true" ]] && server_is_running "$i"; then
			if [[ "$exit_message" == "false" ]]; then
				echo -e "\nInterrupted..."
				exit_message="true"
			fi
			server_eval "$i" "say ${SERVER_RESTART_ABORT[$i]}"
			echo "Server \"${SERVER_NAME[$i]}\" restart was aborted."
		fi
	done
	exit
}

COMMAND_COUNT=0

# Adds a command to the list, allowing it to be called from the command line.
# $1: The command signature, a coded string describing the structure of the
#     command.
# $2: The handler function to call, if this command is identified.
register_command() {
	# Here we build a regular expression which will match any user input
	# that could be passed to the given handler function. It is derrived
	# automatically from the given command signature.
	
	local regex="^"
	
	# Iterate over each element in the command signature
	for word in $1; do
		# Variables are denoted by angle brackets (e.g. "<variable>") and can
		# at this stage be accepted as any non-zero string
		if [[ "$word" =~ ^\<.*\>$ ]]; then
			if [[ "$word" == "<strings>" ]]; then
				regex="${regex}([^ ]+|\\\"[^\\\"]*\\\")( [^ ]+|\\\"[^\\\"]*\\\")+ "
			else
				regex="${regex}([^ ]+|\\\"[^\\\"]*\\\") "
			fi
			continue
		fi
		
		# Sometimes different worlds may be used to call the same command, in
		# these cases, the different words may be written contiguously,
		# separated by the pipe character (i.e. "|") and any of the options
		# provided will be allowed as a match.
		if [[ "$word" =~ \| ]]; then
			regex="${regex}($word) "
			continue
		fi
		
		# Anything else found in the command signature will be taken to mean
		# a fixed string, which must be provided to match this command.
		regex="${regex}$word "
	done
	
	if [ ${#regex} -ge 1 ]; then
		regex="${regex:0:${#regex}-1}\$"
		
		# Sets the global command varibales in order to register this command
		COMMAND_SIGNATURE[$COMMAND_COUNT]="$1"
		COMMAND_REGEX[$COMMAND_COUNT]="$regex"
		COMMAND_HANDLER[$COMMAND_COUNT]="$2"
		
		COMMAND_COUNT=$(( $COMMAND_COUNT + 1 ))
	else
		error_exit FATAL_ERROR "Fatal error: Sorry about this, would you be so kind as to file a bug at http://git.io/2f_x-A and cite: \"Erroneous command regex '${regex}' for signature '${1}'\""
	fi
}

# Match and call a command from user input
# $*: User input
call_command() {

	local args
	local space="\ "
	for arg in "$@"; do
		if [[ "$arg" =~ $space ]]; then
			args="$args\"$arg\" "
		else
			args="$args$arg "
		fi
	done

	if [ ${#args} -ge 1 ]; then
		args="${args:0:${#args}-1}"
	fi

	for ((i=0; i<$COMMAND_COUNT; i++)); do
		if [[ "$args" =~ ${COMMAND_REGEX[$i]} ]]; then
			unset args
			local word_offset=1
			local args
			local arg_offset=0
			local sid=-1
			local wid=-1

			# Helper function to build the argument list
			# $1: The argument to push onto the list
			push_arg() {
				args[$arg_offset]="$1"
				arg_offset="$(( $arg_offset + 1 ))"
			}
			
			# The following loop builds a set of arguments to pass to the
			# matched command handler function. Rather than passing all args
			# given to the script, to the handler (which may contain constant
			# strings), it only includes variables.
			for word in ${COMMAND_SIGNATURE[$i]}; do
				# Whether a positional argument is a varibale or not is
				# determined by the respective element in the command signature
				# given when registering.
				#
				# This case statement handles each possible type of signature
				# token, and pushes the respective user input onto the stack of
				# arguments.
				case "$word" in
					# The "<string>" token expects any type of string argument,
					# accepting spaces, limited to one argument.
					"<string>")
						# Do no checks, just push the argument onto the stack
						push_arg "${!word_offset}"
						;;
					
					
					# The "<strings>" token must only be placed at the end of a
					# commadn signature, and allows an arbitrary amount of
					# arguments to be passed to the command handler function.
					"<strings>")
						# Put all remaining user input onto the argument stack
						for input_arg in "${@:$word_offset}"; do
							push_arg "$input_arg"
						done
						# Break from analysing the rest of the input
						break
						;;
					
					
					# The "<name>" token is similar to "<string>" but adds an
					# extra assurance that the string is a valid name, as used
					# for creating servers and other things.
					"<name>")
						# Check the argument is a valid name and then add push it onto the argument stack
						local specified_name="${!word_offset}"

						if is_valid_name "$specified_name"; then
							push_arg "$specified_name"
						fi
						;;
					
					
					# The "<name:server>" token improves on "<name>" by also
					# checking that the server exists, and passing the argument
					# on as the server id, instead of the server name to
					# command handler functions.
					"<name:server>")
						local specified_name="${!word_offset}"
						if [[ "$specified_name" == "all" ]]; then
							# Do for all servers
							sid="server:all"
						else
							if is_valid_name "$specified_name"; then
								if [ -d "$SERVER_STORAGE_PATH/$specified_name" ]; then
									sid="$(server_get_id "$specified_name")"
								fi
							fi

							if [[ "$sid" -eq "-1" ]]; then
								error_exit NAME_NOT_FOUND "There is no server with the name \"$specified_name\"."
							fi
						fi

						push_arg "$sid"
						;;
						
					
					# The "<name:world>" token also improves upon "<name>" by
					# ensuring that the world actually exists, and passes the
					# argument on to command handlers as the world ID, rather
					# than the original world name input by the user.
					"<name:world>")
						local specified_name="${!word_offset}"

						if [[ "$sid" -eq "-1" ]]; then
							# Server id not set yet
							exit_error 1 "Ill-defined command $*. Please file an issue by opening the following link: https://github.com/marcuswhybrow/minecraft-server-manager/issues"
						fi

						if [[ "$sid" -eq "-2" ]]; then
							if [[ "$specified_name" == "all" ]]; then
								wid="world:all"
							else
								exit_error INVALID_ARGUMENT "When specifying \"all\" servers, \"all\" worlds must be specified also."
							fi
						fi

						if [[ "$sid" -ge "0" ]]; then
							if is_valid_name "$specified_name"; then
								if [ -d "${SERVER_WORLD_ACTIVE_PATH[$sid]}/$specified_name" ] || [ -d "${SERVER_WORLD_INACTIVE_PATH[$sid]}/$specified_name" ]; then
									wid="$(server_world_get_id "$sid" "$specified_name")"
								fi
							fi

							if [ -z "$wid" ]; then
								error_exit NAME_NOT_FOUND "There is no world with the name \"$specified_name\"."
							fi

							push_arg "$wid"
						fi
						;;
				esac

				word_offset=$(( $word_offset + 1 ))
			done

			# The argument list for the call to the command handler has been
			# built. But there are several ways to call a handler. Either just
			# once, or multiple times based upon if multiple servers or worlds
			# were specified.
			

			# This code block calls the handler for all possible servers and
			# all possible worlds.
			if [[ "$sid" == "server:all" ]] && [[ "$wid" == "world:all" ]]; then
				for ((j=0; j<$num_worlds; j++)); do
					# Replace server and world id placeholders with actual id's
					local replaced_args
					for k in ${!args[@]}; do
						replaced_args[$k]="${args[$k]//server:all/${WORLD_SERVER_ID[$j]}}"
						replaced_args[$k]="${args[$k]//world:all/$j}"
					done
					
					# Call the function with the specific replaced args
					${COMMAND_HANDLER[$i]} "${replaced_args[@]}"
				done
				
				# Prevent the default singular call later on.
				return
			fi
			
			# This calls the handler for all possible servers, and preserves 
			# all other arguments.
			if [[ "$sid" == "server:all" ]]; then
				for ((j=0; j<$num_servers; j++)); do
					local replaced_args
					for k in ${!args[@]}; do
						replaced_args[$k]="${args[$k]//server\:all/$j}"
					done
					
					${COMMAND_HANDLER[$i]} "${replaced_args[@]}"
				done
				
				return
			fi
			
			# This calls the handlers for all possible worlds for a specific
			# server.
			if [[ "$sid" != "server:all" ]] && [[ "$wid" == "world:all" ]]; then
				for ((j=${SERVER_WORLD_OFFSET[$sid]}; j<${SERVER_NUM_WORLDS[$sid]}; j++)); do
					local replaced_args
					for k in ${!args[@]}; do
						replaced_args[$k]="${args[$k]//world:all/$j}"
					done
					
					${COMMAND_HANDLER[$i]} "${replaced_args[@]}"
				done
				
				return
			fi
			
			# Otherwise it's a simple single call of the handler.
			${COMMAND_HANDLER[$i]} "${args[@]}"
			return
		fi
	done
	
	echo "No such command. See $0 help"
}

# The main function which starts the script
main() {
	# Initialises variables that represent system state
	init
	
	# Trap interrupts to the script by calling the interrupt function
	trap interrupt EXIT
	
	# The following section registers commands to be available for use. The
	# register_command function accepts a command_signature and a
	# command_handler_function_name as positional arguments 1 and 2
	# respectively.
	#
	# A command signature consists of multiple elements separated by spaces,
	# the available options are as follows:
	#
	#     fixedstring    Matches an argument containing the specified
	#                    characters, in this case the characters "fixedstring"
	#
	#     <string>       Same as "fixedstring", but is variable and the value
	#                    is passed to the handler function as a positional
	#                    argument
	#
	#     <strings>      Same as "<string>", but matches multiple arguments,
	#                    must be final element
	#
	#     <name>         Same as "<string>", also ensures it's a valid name
	#                    using the is_valid_name function
	#
	#     <name:server>  Same as "<name>", also converts value to server id or
	#                    fails if the server does not exist
	#
	#     <name:world>   Same as "<name>", also converts value to world id or
	#                    fails if the world does not exist. Must only be
	#                    included after a "<name:server>" element.
	#     
	# Elements listed above encapsulated within angle brackets must be included
	# within a signature verbatim, as apposed to the "fixedstring" element
	# which is arbitrary.
	#
	# Variables passed to handler functions are of course positional and there
	# position matches the position of that element in the command signature.
	
	register_command "start" "command_start"
	register_command "stop" "command_stop"
	register_command "stop now" "command_stop_now"
	register_command "restart" "command_restart"
	register_command "restart now" "command_restart_now"
	register_command "version" "command_version"
	register_command "server list" "command_server_list"
	register_command "server create <name>" "command_server_create"
	register_command "server delete <name>" "command_server_delete"
	register_command "server rename <name> <name>" "command_server_rename"
	register_command "jargroup list" "command_jargroup_list"
	register_command "jargroup create <name> <string>" "command_jargroup_create"
	register_command "jargroup delete <name>" "command_jargroup_delete"
	register_command "jargroup rename <name> <name>" "command_jargroup_rename"
	register_command "jargroup changetarget <name> <string>" "command_jargroup_changetarget"
	register_command "jargroup getlatest <name>" "command_jargroup_getlatest"
	register_command "help" "command_help"
	register_command "<name:server> start" "command_server_start"
	register_command "<name:server> stop" "command_server_stop"
	register_command "<name:server> stop now" "command_server_stop_now"
	register_command "<name:server> restart" "command_server_restart"
	register_command "<name:server> restart now" "command_server_restart_now"
	register_command "<name:server> status" "command_server_status"
	register_command "<name:server> connected" "command_server_connected"
	register_command "<name:server> worlds list" "command_server_worlds_list"
	register_command "<name:server> worlds load" "command_server_worlds_load"
	register_command "<name:server> worlds ram <name:world>" "command_server_worlds_ram"
	register_command "<name:server> worlds todisk" "command_server_worlds_todisk"
	register_command "<name:server> worlds backup" "command_server_worlds_backup"
	register_command "<name:server> worlds on <name:world>" "command_server_worlds_on"
	register_command "<name:server> worlds off <name:world>" "command_server_worlds_off"
	register_command "<name:server> logroll" "command_server_logroll"
	register_command "<name:server> backup" "command_server_backup"
	register_command "<name:server> jar <name>" "command_server_jar"
	register_command "<name:server> jar <name> <name>" "command_server_jar"
	register_command "<name:server> whitelist|wl on" "command_server_whitelist_on"
	register_command "<name:server> whitelist|wl off" "command_server_whitelist_off"
	register_command "<name:server> whitelist|wl add <string>" "command_server_whitelist_add"
	register_command "<name:server> whitelist|wl remove <string>" "command_server_whitelist_remove"
	register_command "<name:server> whitelist|wl list" "command_server_whitelist_list"
	register_command "<name:server> blacklist|bl player add <string>" "command_server_blacklist_player_add"
	register_command "<name:server> blacklist|bl player remove <string>" "command_server_blacklist_player_remove"
	register_command "<name:server> blacklist|bl ip add <string>" "command_server_blacklist_ip_add"
	register_command "<name:server> blacklist|bl ip remove <string>" "command_server_blacklist_ip_remove"
	register_command "<name:server> blacklist|bl list" "command_server_blacklist_list"
	register_command "<name:server> operator|op add <string>" "command_server_operator_add"
	register_command "<name:server> operator|op remove <string>" "command_server_operator_remove"
	register_command "<name:server> operator|op list" "command_server_operator_list"
	register_command "<name:server> gamemode|gm <string> <string>" "command_server_gamemode"
	register_command "<name:server> kick <string>" "command_server_kick"
	register_command "<name:server> say <strings>" "command_server_say"
	register_command "<name:server> time set <string>" "command_server_time_set"
	register_command "<name:server> time add <string>" "command_server_time_add"
	register_command "<name:server> toggledownfall|tdf" "command_server_toggledownfall"
	register_command "<name:server> give <string> <string>" "command_server_give"
	register_command "<name:server> give <string> <string> <string>" "command_server_give"
	register_command "<name:server> give <string> <string> <string> <string>" "command_server_give"
	register_command "<name:server> xp <string> <string>" "command_server_xp"
	register_command "<name:server> save on" "command_server_save_on"
	register_command "<name:server> save off" "command_server_save_off"
	register_command "<name:server> save all" "command_server_save_all"
	register_command "<name:server> cmd <strings>" "command_server_cmd"
	register_command "<name:server> cmdlog <strings>" "command_server_cmdlog"
	register_command "<name:server> console" "command_server_console"
	
	# This function call matches the user input to a registered command
	# signature, and then calls that commands handler function with positional
	# arguments containing any variable strings.
	call_command "$@"
}


### Start point

main "$@"
exit 0