module Devise::Models::Recoverable

def self.required_fields(klass) 

def self.required_fields(klass)
  [:reset_password_sent_at, :reset_password_token]
end

def after_password_reset 

def after_password_reset
end

def clear_reset_password_token

Removes reset_password token 
def clear_reset_password_token
  self.reset_password_token = nil
  self.reset_password_sent_at = nil
end

def generate_reset_password_token

Generates a new random token for reset password 
def generate_reset_password_token
  self.reset_password_token = self.class.reset_password_token
  self.reset_password_sent_at = Time.now.utc
  self.reset_password_token
end

def generate_reset_password_token!

validating
Resets the reset password token with and save the record without 
def generate_reset_password_token!
  generate_reset_password_token && save(:validate => false)
end

def reset_password!(new_password, new_password_confirmation)

the passwords are valid and the record was saved, false otherwise.
Update password saving the record and clearing token. Returns true if 
def reset_password!(new_password, new_password_confirmation)
  self.password = new_password
  self.password_confirmation = new_password_confirmation
  if valid?
    clear_reset_password_token
    after_password_reset
  end
  save
end

def reset_password_period_valid?


reset_password_period_valid? # will always return false
# reset_password_within = 0.days

reset_password_period_valid? # returns false
# reset_password_within = 5.days and reset_password_sent_at = 5.days.ago

reset_password_period_valid? # returns true
# reset_password_within = 5.days and reset_password_sent_at = 4.days.ago

reset_password_period_valid? # returns true
# reset_password_within = 1.day and reset_password_sent_at = today

Example:

reset_password_within is a model configuration, must always be an integer value.
Returns true if the resource is not responding to reset_password_sent_at at all.
sending date does not exceed the confirm in time configured.
We do this by calculating if the difference between today and the
Checks if the reset password token sent is within the limit time. 
def reset_password_period_valid?
  reset_password_sent_at && reset_password_sent_at.utc >= self.class.reset_password_within.ago
end

def send_reset_password_instructions

Resets reset password token and send reset password instructions by email 
def send_reset_password_instructions
  generate_reset_password_token! if should_generate_reset_token?
  send_devise_notification(:reset_password_instructions)
end

def should_generate_reset_token? 

def should_generate_reset_token?
  reset_password_token.nil? || !reset_password_period_valid?
end