# -*- coding: utf-8 -*-
        
      
        

          
          
          =begin rdoc
        
      
        

          
          
          Please see README
        
      
        

          
          
          =end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

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          if !defined?(SecureRandom)
        
      
        

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            begin
        
      
        

          
          
              # First we will try to load the Ruby standard library
        
      
        

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              require 'securerandom'
        
      
        

          
          
            rescue
        
      
        

          
          
              # Second we will try to load our own SecureRandom gem library
        
      
        

          
          
              require 'sixarm_ruby_secure_random'
        
      
        

          
          
            end
        
      
        

          
          
          end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

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          class PasswordText < String
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Default characters
        
      
        

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           DEFAULT_CHARS=['a','b','c','d','e','f','g','h','j','k','m','n','p','q','r','s','t','u','v','w','x','y','z']
        
      
        

          
          
          
        
      
        

          
          
           # Default length
        
      
        

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           DEFAULT_LEN=12
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Return a new secure random password.
        
      
        

          
          
           #
        
      
        

          
          
           # The password has a given length (or the default)
        
      
        

          
          
           # and is picked from a given character array (or the default).
        
      
        

          
          
           #
        
      
        

          
          
           # To set the default length, see #length
        
      
        

          
          
           #
        
      
        

          
          
           # To set the default character array, see #chars
        
      
        

          
          
           #
        
      
        

          
          
           # ==Examples
        
      
        

          
          
           #   password = PasswordText.new => "avzwbnxremcd"
        
      
        

          
          
           #   password = PasswordText.new(4) => "avzw"
        
      
        

          
          
           #   password = PasswordText.new(4,['x','y','z']) => "yzyx"
        
      
        

          
          
          
        
      
        

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           def initialize(opts={})
        
      
        

          
          
             self.chars= opts[:chars] || DEFAULT_CHARS
        
      
        

          
          
             self.len= opts[:len] || DEFAULT_LEN
        
      
        

          
          
             super(Array.new(len){chars[SecureRandom.random_number(chars.size)]}.join)
        
      
        

          
          
           end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Get the default character array.
        
      
        

          
          
           #
        
      
        

          
          
           # To improve usability, the passwords only use lowercase letters.
        
      
        

          
          
           # This helps people who use mobile phones and also helps people
        
      
        

          
          
           # who have some kinds disabilities related to manual dexterity.
        
      
        

          
          
           # We also omit letters that may be confused with numbers: "i", "l", "o".
        
      
        

          
          
           #
        
      
        

          
          
           # We choose this as a valuable tradeoff between usability and complexity.
        
      
        

          
          
          
        
      
        

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           def chars
        
      
        

          
          
            @chars || DEFAULT_CHARS
        
      
        

          
          
           end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Set the default character array
        
      
        

          
          
          
        
      
        

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           def chars=(chars)
        
      
        

          
          
            @chars=chars
        
      
        

          
          
           end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Get the default length
        
      
        

          
          
           #
        
      
        

          
          
           # We choose 12 characters to make a sufficiently strong password.
        
      
        

          
          
           # for usual web applications. You can make this stronger as needed.
        
      
        

          
          
          
        
      
        

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           def len
        
      
        

          
          
            @len || DEFAULT_LEN
        
      
        

          
          
           end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Set the default length
        
      
        

          
          
          
        
      
        

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           def len=(length)
        
      
        

          
          
            @len=length
        
      
        

          
          
           end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
           # Return the next random password of the same length and character array
        
      
        

          
          
          
        
      
        

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           def next
        
      
        

          
          
             PasswordText.new(:chars => chars, :len => len)
        
      
        

          
          
           end
        
      
        

          
          
          
        
      
        

          
          
          
        
      
        

          
          
          end