#!/bin/bash
#
# @(#) Create a new user in OSX. V1.1
#
# xaos@xm5design.com - July 14, 2010
#
DSCLLIST="/tmp/dsclist.txt"
DSCLLISTS="/tmp/dsclists.txt"
DRURUN=0
NUSER="newuser"
FIND_NEXT_UID=0
#
#
usage() {
	echo "Usage: $0 [ -l [user] | -h | -a | -d ] User_Name { UID | . } GID"
	echo -e "\nWhere:\n"
	echo -e "\t-a\t\tWill create the user as an administrator"
	echo -e "\t-d\t\tWill do a \"Dry Run\". It will check everything but not run any commands"
	echo -e "\t-h\t\tWill print this help message"
	echo -e "\t-l [user]\tWill list a user or all users and quit"
	echo -e "\nSpecifying a \".\" (dot) for a UID means find the next available one."
	echo -e "If the GID does not exist, the necessary commands to create it will be printed out." 
	echo -e "A default password (made of random numbers) will be created along with the userid."
}

#
# This only works for Darwin
	if [[ "$(uname -s)" != "Darwin" ]]
	then
		echo "This script will only work for OSX"
		exit 1
	fi
#
#
	NUSER=$1
	NUID=$2
	NGID=$3
	NADMIN=0
#
# Get help ?
	if [[ "${NUSER}" = "-h"* ||  "${NUSER}" = "--h"* ]]
	then
		usage
		exit 1
	fi
#
# Show a list of users?
	if [[ "${NUSER}" = "-l" ]]
	then
		shift
		MUSER=$1
		if [[ "${MUSER}" == "" ]]
		then
			GENULIST=$(dscl "." list /users | sort -k 1)
		else
			GENULIST=${MUSER}
		fi
		#
		DSCGLIST=$(dscl . list /Groups)
		#
		for ii in ${GENULIST}
		do
			echo "${ii}"
			dscl . read /Users/${ii} | egrep "PrimaryGroupID|NFSHomeDirectory|RealName|UniqueID|UserShell" >${DSCLLIST}
			while read line
			do
				if [[ "${line}" = *PrimaryGroupID* ]]
				then
					set $line
					gtext=$1;gnumid=$2
					foundid=0
					#
					for kk in ${DSCGLIST}
					do
						GIDTEXT=$(dscl . read /Groups/$kk | grep PrimaryGroupID)
						set $GIDTEXT
						gtextg=$1; gnumidg=$2
						#
						# now, compare the two
						if (( gnumid == gnumidg ))
						then
							foundid=1
							foundname=$kk
							break
						fi
					done
					if (( foundid ))
					then
						echo -e "\tPrimaryGroupID:\n\t\tName   : ${foundname}\n\t\tNumber : ${gnumid}\n\t\tExists : Yes"
					else
						echo -e "\tPrimaryGroupID:\n\t\tName   : ${foundname}\n\t\tNumber : ${gnumid}\n\t\tExists : No"
					fi
				else
					set $line
					key=$1
					shift
					keytext=$*
					echo -e "\t${key}\n\t\t\"${keytext}\""
				fi
			done < ${DSCLLIST}
		done
		rm -f ${DSCLLIST}
		exit 0
	fi
#
# Does he need to be admin or dry run?
	while :
	do
		if [[ "${NUSER}" = "-"* ]]
		then
			if [[ "${NUSER}" = "-a" ]]
			then
				NADMIN=1
			elif [[ "${NUSER}" = "-d" ]]
			then
				DRYRUN=1
			else
				echo "Error: Unknown option: \"${NUSER}\". Bye."
				exit
			fi
			shift
			NUSER=$1
			NUID=$2
			NGID=$3
		else
			break
		fi
	done
#
# Check for no parms
	if [[ "${NGID}" = "" ]]
	then
		usage
		exit 1
	fi
#
# Check if the user exists
	if dscl "." read /Users/${NUSER} >/dev/null 2>&1
	then
		echo -e "User: \"${NUSER}\",  already exists. Bye."
		exit 1
	fi
#
#
if [[ "${NUID}" = "." ]]
then
	FIND_NEXT_UID=1
fi

#
#
if (( FIND_NEXT_UID ))
then
	#
	# Go through every id
		GENULIST=$(dscl "." list /Users | sort -k 1)
		rm -rf ${DSCLLIST}
		for ii in ${GENULIST}
		do
			dscl . read /Users/${ii} | egrep "UniqueID" >>${DSCLLIST}
		done
		cat ${DSCLLIST} | awk '{print $2}' | sort -n > ${DSCLLISTS}
		vim  ${DSCLLISTS}
		NUID=$(tail -1 ${DSCLLISTS})
		let NUID=$NUID+1
		echo -e "New UID found: \"${NUID}\""
		rm -f ${DSCLLIST} ${DSCLLISTS}
fi
#
# Check if the UID exists
	GENULIST=$(dscl "." list /Users | sort -k 1)
	#
	foundid=0
	for ii in ${GENULIST}
	do
		dscl . read /Users/${ii} | egrep "UniqueID" >${DSCLLIST}
		while read line
		do
			set $line
			text=$1;numid=$2
			if (( numid == NUID ))
			then
				foundid=1
				break
			fi
		done < ${DSCLLIST}
	done
	rm -f ${DSCLLIST}
	#
	# Check it
	if (( foundid ))
	then
		echo -e "UID: \"${NUID}\", already exists. Bye."
		exit 1
	else
		echo -e "UID: \"${NUID}\", does not exist. Cool."
	fi
#
# Check if the GID exists
	GENULIST=$(dscl "." list /Groups | sort -k 1)
	#
	foundid=0
	for ii in ${GENULIST}
	do
		dscl . read /Groups/${ii} | egrep "PrimaryGroupID" >${DSCLLIST}
		while read line
		do
			set $line
			text=$1;numid=$2
			if (( numid == NGID ))
			then
				foundid=1
				break
			fi
		done < ${DSCLLIST}
	done
	rm -f ${DSCLLIST}
	#
	# Check it
	if (( foundid ))
	then
		echo -e "GID: \"${NGID}\", exists. Cool."
	else
		echo -e "GID: \"${NGID}\", does not exist.\n\tYou must create with commands:"
		echo -e "\t\tdscl . create /Groups/${NUSER}"
		echo -e "\t\tdscl . create /Groups/${NUSER} name ${NUSER}"
		echo -e "\t\tdscl . create /Groups/${NUSER} passwd \"*\""
		echo -e "\t\tdscl . create /Groups/${NUSER} gid ${NGID}"
		echo -e "\t\tdscl . create /Groups/${NUSER} users  ${NUSER}"
	fi
#
#
	MYNAME="Dr. Maximvs ${NUSER}"
	MYPASS=$(printf "%d\n" "${RANDOM}${RANDOM}${RANDOM}")
#
	if (( DRYRUN ))
	then
		echo -e "Preparing New Account\n\tUser: \"${NUSER}\"\n\tName: \"${MYNAME}\"\n\tUID: \"${NUID}\"\n\tGID: \"${NGID}\"\n\tPassword: \"${MYPASS}\""
		exit
	fi
#
# Process request
	dscl "." -create /Users/${NUSER} || exit 1

	#
	# Create and set the shell property to bash.
	dscl "." -create /Users/${NUSER} UserShell /bin/bash || { echo "Error Creating User Shell. Account was never created"; exit 1; }

	#
	# Create and set the user’s full name.
	dscl "." -create /Users/${NUSER} RealName "${MYNAME}" || { echo -e "Error Creating User Real Name. Account Will be deleted"; dscl . delete /Users/${NUSER}; exit 1; }

	#
	# Create and set the user’s ID.
	dscl "." -create /Users/${NUSER} UniqueID ${NUID} || { echo -e "Error Creating UID. Account Will be deleted"; dscl . delete /Users/${NUSER}; exit 1; }

	#
	# Create and set the user’s group ID property.
	dscl "." -create /Users/${NUSER} PrimaryGroupID ${NGID} || { echo -e "Error Creating GID. Account Will be deleted"; dscl . delete /Users/${NUSER}; exit 1; }

	#
	# Create and set the user home directory.
	dscl "." -create /Users/${NUSER} NFSHomeDirectory /Users/${NUSER} || { echo -e "Error Creating Home Directory. Account Will be deleted"; dscl . delete /Users/${NUSER}; exit 1; }

	#
	# Set the password.
	dscl "." passwd /Users/${NUSER} ${MYPASS} || { echo -e "\nError Creating User Password. Continuing"; dscl . delete /Users/${NUSER}; exit 1; }

	echo -e "New User created.\n\tUser: \"${NUSER}\"\n\tName: \"${MYNAME}\"\n\tDUID: \"${NUID}\"\n\tGID: \"${NGID}\"\n\tPassword: \"${MYPASS}\""

	if (( NADMIN ))
	then
		#
		# If you would like Dr. Maximus to be able to perform administrative functions:
		dscl "." -append /Groups/admin GroupMembership ${NUSER} || exit 1
		echo -e "\tAdministrator: \"Yes\""
	else
		echo -e "\tAdministrator: \"No\""
	fi
	#
	# Create the home dir
		createhomedir -c > /dev/null || exit 1
		chmod 700 /Users/${NUSER}
	#
	# Now, check with Dscl
		echo "Now Checking with dscl:"
		dscl . read /Users/${NUSER} | sed 's/^/	/'
	#
	echo -e "\nTo Delete the user do:\n\tdscl \".\" delete /Users/${NUSER}"
#
exit 0