#!/usr/bin/ruby
#
# adduser - Unix-like adduser script. Prompts for parameters and uses dscl internally to create
#           new NetInfo users and groups.
#
# Chetan Sarva <csarva@pixelcop.net>

def next_user_id(start = 700)
    ids = `dscl . -list /Users UniqueID`.split("\n").map{|s| s =~ /(\d+)$/; $1 }.sort.uniq
    n = start
    while ids.include? n.to_s do
        n += 1
    end
    n
end

def next_group_id(start = 700)
    ids = `dscl . -list /Groups PrimaryGroupID`.split("\n").map{|s| s =~ /(\d+)$/; $1 }.sort.uniq
    n = start
    while ids.include? n.to_s do
        n += 1
    end
    n
end

puts "adduser!"
puts

print "username: "
username = STDIN.gets
username.strip!
if username.empty? then
    puts "must enter a username!"
    exit
end
dusername = "_#{username}"

print "home dir [default=/var/empty]: "
home = STDIN.gets
home = "/var/empty" if home.strip.empty?
home.strip!

password = "*"

def_group_id = next_group_id()
print "group id (default=#{def_group_id}): "
group_id = STDIN.gets
group_id = def_group_id if group_id.strip.empty?
group_id.strip! if group_id.kind_of? String

def_user_id = next_user_id()
print "user id (default=#{def_user_id}): "
user_id = STDIN.gets
user_id = def_user_id if user_id.strip.empty?
user_id.strip! if user_id.kind_of? String

print "real name (default=daemon): "
realname = STDIN.gets
realname = "daemon" if realname.strip.empty?
realname.strip!

print "shell: (default=/usr/bin/false): "
shell = STDIN.gets
shell = "/usr/bin/false" if shell.strip.empty?
shell.strip!


cmd = "sudo dscl localhost -create /Local/Default/Groups/#{dusername}"
system("#{cmd}")
system("#{cmd} PrimaryGroupID #{group_id}")
system("sudo dscl localhost -append /Local/Default/Groups/#{dusername} RecordName #{username}")

cmd = "sudo dscl localhost -create /Local/Default/Users/#{dusername}"

system("#{cmd}")
system("#{cmd} UniqueID #{user_id}")
system("#{cmd} PrimaryGroupID #{group_id}")
system("#{cmd} UserShell #{shell}")
system("#{cmd} RealName '#{realname}'")
system("#{cmd} NFSHomeDirectory #{home}")
system("#{cmd} Password '#{password}'")
system("sudo dscl localhost -append /Local/Default/Users/#{dusername} RecordName #{username}")