Module: Petrarca::Helpers

Extended by:
Helpers
Included in:
Helpers
Defined in:
lib/petrarca/helpers.rb

Instance Method Summary collapse

Instance Method Details

#split(isbn) ⇒ Object 



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# File 'lib/petrarca/helpers.rb', line 10

def split(isbn)
  isbn = Petrarca.dehyphenate(isbn)
  ean_prefix = isbn[0, 3]
  unless ean_prefix == "978" || ean_prefix == "979"
    raise InvalidEANPrefixError.new("Invalid EAN prefix: #{ean_prefix}")
  end
  body = isbn[3, 9]
  check_digit = isbn[12, 1]
  begin
    registration_group, body = Helpers.split_to_parts(body, REGISTRATION_GROUP_RANGES[ean_prefix])
  rescue InvalidRangeError
    raise InvalidRangeError.new("Registration group is not defined: #{body} (under #{ean_prefix})")
  end
  prefix = "#{ean_prefix}-#{registration_group}"
  begin
    registrant, publication = Helpers.split_to_parts(body, REGISTRANT_RANGES[prefix])
  rescue InvalidRangeError
    raise InvalidRangeError.new("Registrant is not defined: #{body} (under #{prefix})")
  end
  [ean_prefix, registration_group, registrant, publication, check_digit]
end

#split_to_parts(body, ranges) ⇒ Object 



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# File 'lib/petrarca/helpers.rb', line 33

def split_to_parts(body, ranges)
  parts = ranges.map do |range|
    s, e = range
    prefix = body[0, s.size]
    if Range.new(s, e).cover?(prefix)
      [prefix, body[(prefix.size)..]]
    else
      nil
    end
  end.compact
  unless parts.empty?
    parts.first
  else
    raise InvalidRangeError.new(body)
  end
end