module Devise

def self.add_mapping(resource, options)

Small method that adds a mapping to Devise. 
def self.add_mapping(resource, options)
  mapping = Devise::Mapping.new(resource, options)
  @@mappings[mapping.name] = mapping
  @@default_scope ||= mapping.name
  @@helpers.each { |h| h.define_helpers(mapping) }
  mapping
end

def self.add_module(module_name, options = {})


Devise.add_module(:party_module, :model => 'party_module/model')
Devise.add_module(:party_module, :strategy => true, :controller => :sessions)
Devise.add_module(:party_module)

== Examples:

name.
All values, except :model, accept also a boolean and will have the same name as the given module

+strategy+ - Symbol representing if this module got a custom *strategy*.
+route+ - Symbol representing the named *route* helper for this module.
+controller+ - Symbol representing the name of an exisiting or custom *controller* for this module.
+model+ - String representing the load path to a custom *model* for this module (to autoload.)

== Options:

Make Devise aware of an 3rd party Devise-module (like invitable). For convenience. 
def self.add_module(module_name, options = {})
  ALL << module_name
  options.assert_valid_keys(:strategy, :model, :controller, :route, :no_input)
  if strategy = options[:strategy]
    strategy = (strategy == true ? module_name : strategy)
    STRATEGIES[module_name] = strategy
  end
  if controller = options[:controller]
    controller = (controller == true ? module_name : controller)
    CONTROLLERS[module_name] = controller
  end
  NO_INPUT << strategy if options[:no_input]
  if route = options[:route]
    case route
    when TrueClass
      key, value = module_name, []
    when Symbol
      key, value = route, []
    when Hash
      key, value = route.keys.first, route.values.flatten
    else
      raise ArgumentError, ":route should be true, a Symbol or a Hash"
    end
    URL_HELPERS[key] ||= []
    URL_HELPERS[key].concat(value)
    URL_HELPERS[key].uniq!
    ROUTES[module_name] = key
  end
  if options[:model]
    path = (options[:model] == true ? "devise/models/#{module_name}" : options[:model])
    camelized = ActiveSupport::Inflector.camelize(module_name.to_s)
    Devise::Models.send(:autoload, camelized.to_sym, path)
  end
  Devise::Mapping.add_module module_name
end

def self.apply_schema=(value) 

def self.apply_schema=(value)
  warn "\n[DEVISE] Devise.apply_schema is deprecated and has no effect. Please remove it.\n"
end

def self.available_router_name 

def self.available_router_name
  router_name || :main_app
end

def self.configure_warden! #:nodoc:

:nodoc:
block.
A method used internally to setup warden manager from the Rails initialize 
def self.configure_warden! #:nodoc:
  @@warden_configured ||= begin
    warden_config.failure_app   = Devise::Delegator.new
    warden_config.default_scope = Devise.default_scope
    warden_config.intercept_401 = false
    Devise.mappings.each_value do |mapping|
      warden_config.scope_defaults mapping.name, :strategies => mapping.strategies
    end
    @@warden_config_block.try :call, Devise.warden_config
    true
  end
end

def self.encryptor=(value) 

def self.encryptor=(value)
  warn "\n[DEVISE] To select a encryption which isn't bcrypt, you should use devise-encryptable gem.\n"
end

def self.friendly_token

Generate a friendly string randomically to be used as token. 
def self.friendly_token
  SecureRandom.base64(15).tr('+/=lIO0', 'pqrsxyz')
end

def self.include_helpers(scope)

Include helpers in the given scope to AC and AV. 
def self.include_helpers(scope)
  ActiveSupport.on_load(:action_controller) do
    include scope::Helpers if defined?(scope::Helpers)
    include scope::UrlHelpers
  end
  ActiveSupport.on_load(:action_view) do
    include scope::UrlHelpers
  end
end

def self.mailer

Get the mailer class from the mailer reference object. 
def self.mailer
  @@mailer_ref.get
end

def self.mailer=(class_name)

Set the mailer reference object to access the mailer. 
def self.mailer=(class_name)
  @@mailer_ref = ref(class_name)
end

def self.omniauth(provider, *args)


config.omniauth :github, APP_ID, APP_SECRET

Specify an omniauth provider. 
def self.omniauth(provider, *args)
  @@helpers << Devise::OmniAuth::UrlHelpers
  config = Devise::OmniAuth::Config.new(provider, args)
  @@omniauth_configs[config.strategy_name.to_sym] = config
end

def self.omniauth_providers 

def self.omniauth_providers
  omniauth_configs.keys
end

def self.ref(arg) 

def self.ref(arg)
  if defined?(ActiveSupport::Dependencies::ClassCache)
    ActiveSupport::Dependencies::reference(arg)
    Getter.new(arg)
  else
    ActiveSupport::Dependencies.ref(arg)
  end
end

def self.regenerate_helpers!

Regenerates url helpers considering Devise.mapping 
def self.regenerate_helpers!
  Devise::Controllers::UrlHelpers.remove_helpers!
  Devise::Controllers::UrlHelpers.generate_helpers!
end

def self.secure_compare(a, b)

constant-time comparison algorithm to prevent timing attacks 
def self.secure_compare(a, b)
  return false if a.blank? || b.blank? || a.bytesize != b.bytesize
  l = a.unpack "C#{a.bytesize}"
  res = 0
  b.each_byte { |byte| res |= byte ^ l.shift }
  res == 0
end

def self.setup

a fresh initializer with all configuration values.
Default way to setup Devise. Run rails generate devise_install to create 
def self.setup
  yield self
end

def self.use_salt_as_remember_token=(value) 

def self.use_salt_as_remember_token=(value)
  warn "\n[DEVISE] Devise.use_salt_as_remember_token is deprecated and has no effect. Please remove it.\n"
end

def self.warden(&block)

end
end
manager.oauth(:twitter)
# Configure warden to use other strategies, like oauth.
config.warden do |manager|

config.allow_unconfirmed_access_for = 2.days
Devise.initialize do |config|

initialization.
Sets warden configuration using a block that will be invoked on warden 
def self.warden(&block)
  @@warden_config_block = block
end