Class: EAN13

Inherits:
Object
  • Object
show all
Defined in:
lib/ean13.rb

Defined Under Namespace

Classes: Version

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(str) ⇒ EAN13

Returns a new instance of EAN13.



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# File 'lib/ean13.rb', line 13

def initialize(str)
  @number = str.to_s
end

Class Method Details

.complete(twelve) ⇒ Object

Purely for generating new ean numbers



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# File 'lib/ean13.rb', line 31

def self.complete(twelve)
  twelve = twelve.to_s
  return nil unless twelve.length == 12 && twelve.match(/\d{11}/)

  arr = (0..11).to_a.collect do |i|
    if (i+1) % 2 == 0
      twelve[i,1].to_i * 3
    else
      twelve[i,1].to_i
    end
  end
  sum = arr.inject { |sum, n| sum + n }
  remainder = sum % 10
  if remainder == 0
    check = 0
  else
    check = 10 - remainder
  end

  twelve + check.to_s
end

.valid?(ean) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ean13.rb', line 25

def self.valid?(ean)
  ean = ean.to_s
  ean.length == 13 && ean == EAN13.complete(ean[0,12])
end

Instance Method Details

#bookland? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ean13.rb', line 21

def bookland?
  valid? && (@number[0,3] == "978" || @number[0,3] == "979")
end

#san? ⇒ Boolean

Returns true if this EAN has an embedded SAN

For more info on SANs, see www.bowker.com/index.php/component/content/article/3

Returns:

  • (Boolean) 


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# File 'lib/ean13.rb', line 58

def san?
  return nil unless valid?

  prefix = @number.to_s[0,6]
  if prefix == "079999" || prefix == "503067"
    true
  else
    false
  end
end

#to_gtin ⇒ Object 



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# File 'lib/ean13.rb', line 88

def to_gtin
  return nil unless self.valid?
  "0#{@number}"
end

#to_san ⇒ Object

convert this EAN to a SAN. returns nil if the EAN doesn’t contain an embedded SAN.

requires the SAN library to be loaded or available. Will raise an error if it’s not



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# File 'lib/ean13.rb', line 75

def to_san
  unless Kernel.const_defined?("SAN")
    begin
      gem 'san'
      require 'san'
    rescue Exception => e
      raise LoadError, "Could not load require SAN library. Try installing the san rubygem."
    end
  end
  return nil unless san?
  SAN.complete(@number[6,6])
end

#to_upc ⇒ Object 



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# File 'lib/ean13.rb', line 93

def to_upc
  return nil unless self.valid?
  return nil unless @number[0,1] == "0"
  @number[1,12]
end

#valid? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ean13.rb', line 17

def valid?
  EAN13.valid? @number
end