require 'fileutils'

POSIX_NAME_PREFIX = "emacs"


$user_count = 0
$users = []
$id_map = {}


## User manipulation

class User
  attr_accessor :id, :path, :posixname

  def to_s
    "#{@id}, #{@path}"
  end
end

def get_user(id)
  $id_map[id]
end

def add_user(id)
  if not system("useradd -m #{POSIX_NAME_PREFIX}#{id}") then
    raise "User creation failed"
  end
  
  user = User.new
  user.id = id
  user.path = "/home/#{POSIX_NAME_PREFIX}#{id}"
  user.posixname = "#{POSIX_NAME_PREFIX}#{id}"
  $user_count += 1
  $users << user
  $id_map[id] = user

  FileUtils.mkdir "#{user.path}/.ssh"
  FileUtils.touch "#{user.path}/.ssh/authorized_keys"
  FileUtils.chown_R user.id, user.id, "#{user.path}/.ssh"
  
  user
end

def remove_user(id)
  system("userdel -r #{POSIX_NAME_PREFIX}#{id}")
  $user_count -= 1
end

## Key manipulation

class SSHKey
  attr_accessor :cipher, :pubkey, :comment

  def initialize(cipher,pubkey,comment="")
    @cipher  = cipher
    @pubkey  = pubkey
    @comment = comment
  end
end

def get_ssh_keys(id)
  user = get_user(id)
  extract_ssh_keys("#{user.path}/.ssh/authorized_keys").each do |k|
    puts k.comment
  end
end

def extract_ssh_keys(file)
  File.open(file,"r") do |f|
    f.read.split("\n").select{ |line| line[0..2] == "ssh" }.map{ |ks| k = ks.split(" "); SSHKey.new(k[0][4..6], k[1], k[2]) }
  end
end