# frozen_string_literal: true

class Client < ApplicationRecord

  def self.new_client(params)
    perm_string = params[:permission] || 'w' # create write client by default
    perm_rwx = Client.parse_perm_string(perm_string)

    new(params.except(:permission)).tap do |client|
      client.name_id = Digest::SHA1.hexdigest(client.name + SecureRandom.base64(8))[0, 8]
      client.perm_r = perm_rwx[:r]
      client.perm_w = perm_rwx[:w]
      client.perm_x = perm_rwx[:x]
    end
  end

  def update_client(params)
    perm_rwx = Client.parse_perm_string(params[:permission])

    update(params.except(:permission))
    return unless perm_rwx

    self.perm_r = perm_rwx[:r]
    self.perm_w = perm_rwx[:w]
    self.perm_x = perm_rwx[:x]
  end

  def gen_api_key
    api_key = SecureRandom.hex(32)
    self.api_key = api_key
    "#{RynDNS::Application::API_KEY_PREFIX}.#{self.name_id}.#{api_key}"
  end

  def api_key
    @api_key ||= BCrypt::Password.new(api_key_hash)
  end

  def api_key=(new_api_key)
    @api_key = BCrypt::Password.create(new_api_key) # TODO: benchmark cost on target hw
    self.api_key_hash = @api_key
  end

  def permission
    "#{'r' if perm_r}#{'w' if perm_w}#{'x' if perm_x}"
  end

  def read?
    perm_r
  end

  def write?
    perm_w
  end

  def admin?
    perm_x
  end

  def self.number_of_admins
    Client.where({ perm_x: true }).count
  end

  def self.admins?
    Client.number_of_admins >= 1
  end

  # helper functions
  def self.parse_perm_string(perm_string)
    return nil unless perm_string.is_a?(String)

    perm_rwx = { r: false, w: false, x: false }
    return perm_rwx unless perm_string

    perm_string.each_char { |c| perm_rwx[c.to_sym] = true unless perm_rwx[c.to_sym].nil? }
    perm_rwx
  end

  # validations
  validates_presence_of :name, :name_id, :api_key_hash
  validates :name, length: { in: 3..20 }, uniqueness: true
  validates :name_id, length: { is: 8 }, uniqueness: true
  validates :description, length: { maximum: 200 }
  validates :ipv4, length: { maximum: 15 }
  validates_format_of :name, with: /\A([0-9a-zA-z_\-.@]){3,20}\z/i

end