require 'fileutils'
require 'scrypt'
require_relative 'user'
require_relative 'project'
require_relative 'sshkey'

POSIX_NAME_PREFIX = "emacs"
USER_LOCATION = "./users/"
DATA_PATH = "/home/christoffermadsen/git/emacs-collab/data"


require_relative 'database/sqlite'
$db = EmacsCollab::Database::SQLite.new "test"

module EmacsCollab

  # TODO: Fix this weird definition
  
  #####################
  # User manipulation #
  #####################

  def self.create_user(id)
    user = User.new(id)
    add_user(user)
  end

  def self.add_user(user)
    $db.add_user(user)
  end

  def self.get_user_by_id(id)
    $db.get_user(id)
  end

  def self.change_user_password(id,password)
    user = get_user_by_id(id)

    hash, salt = salthash_password(password)
    $db.change_user_password(user, hash, salt)
  end

  def self.check_password(id, password)
    user = get_user_by_id(id)

    hash = salthash_password(password, user.salt)[0]

    user.pw_hash == hash
  end

  def self.salthash_password(password, salt = SCrypt::Engine.generate_salt)
    hash = SCrypt::Engine.hash_secret(password,salt)
    return hash, salt
  end

  ########################
  # Project manipulation #
  ########################

  def self.get_project(id)
    $db.get_project(id)
  end

  def self.add_project(project)
    $db.add_project(project)
  end

  def self.create_project(id)
    if get_project(id) then
      raise DuplicateProjectError, "Project with id #{id} already exists"
    end
    
    if not system("useradd -m #{POSIX_NAME_PREFIX}#{id} -s /usr/bin/eshell") then
      raise "Project creation failed"
    end 
    
    project = Project.new
    project.id = id
    project.path = "/home/#{POSIX_NAME_PREFIX}#{id}"
    project.posixname = "#{POSIX_NAME_PREFIX}#{id}"

    FileUtils.mkdir "#{project.path}/.ssh"
    FileUtils.touch "#{project.path}/.ssh/authorized_keys"
    FileUtils.touch "#{project.path}/.ssh/users"
    FileUtils.chown_R project.posixname, project.posixname, "#{project.path}/.ssh"

    add_project(project)
    
    project
  end

  def self.remove_project(project)
    system("userdel -r #{project.posixname}")
    $db.remove_project(project)
  end

  def self.load_project_from_posix_name(posix_name)
    project = Project.new
    project.id = posix_name[POSIX_NAME_PREFIX.length..-1]
    project.path = "/home/#{posix_name}"
    project.posixname = posix_name
    project
  end

  ####################
  # Key manipulation #
  ####################

  def self.get_ssh_keyfile(project,mode,&block)
    file = File.open("#{project.path}/.ssh/authorized_keys",mode)
    return file unless block_given?
    yield(file)
  ensure
    file.close
  end

  def self.get_ssh_pubkeys(project)
    extract_ssh_pubkeys("#{project.path}/.ssh/authorized_keys")
  end

  def self.valid_pubkey?(key)
    IO.popen("ssh-keygen -qlf -","r+") do |io|
      io.write key.to_s
      io.close_write
      io.read
    end
    if $?.to_i == 0
      true
    else
      false
    end
  end

  def self.extract_ssh_pubkeys(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

  ################


  ###########
  # Project $DB #
  ###########

  def self.reload_projects_from_passwd
    $projects = []
    `cut -d: -f1 /etc/passwd`.split("\n").
      select{|u| u.start_with? POSIX_NAME_PREFIX}.
      map{|u| load_project_from_posix_name(u)}.
      each{|u| add_project(u)}
    $projects.each{|p| p.refresh}
  end

  def self.reload_users_from_dir
    `ls -1 #{USER_LOCATION}`.split("\n").
      map{|u| User.new(u)}.
      each{|u| add_user(u.id)}
  end

  def self.flush_all_to_disk
    $users.each {|u| u.flush}
    $projects.each {|p| p.flush}
  end
  
  def self.flush_projects_with_user(user)
    $projects.select{|p| p.users.include? user}.each do |p|
      p.flush
    end
  end

  ################################################

end
  
  #reload_users_from_dir
  #reload_projects_from_passwd

  #remove_project 5
  #create_project 3
  #add_ssh_pubkey(get_project(3), "ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQC7ZKN2fKcUQUaQqDjNCQQBSdqBVGX7lprNCJmceDBfybhbnuZJ8KvzJJIJIIbzqheW5BVCfkWJY6OgkpAumLWSRCS5n2+AnDHwQgpKDS93OeV+9/kattVtsVUBZaghymyJ2UfA0r918dkxcT9SZbNSl9raiDUUmj3JY8UM219BQP7BRqoZ6e/YZz9lO7ORy6yQT6fIMaVOaZcoDPr6oyNJfadm9POvS/Wl63onoRI9dzpHQG9RuHCcUhHJhkGtzY7GeRWc85WqA9Q4vYo0SK5Je9BG1cvAAVTfV+eYEJEiSDMwWj60roH0C3/ipmzxD/kWqg6YBJWL+XAyQkDnmbuD christoffermadsen@strawberry.thedevcave.net")