Class: BitMask::Field

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(name, opts) ⇒ Field

Returns a new instance of Field.



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# File 'lib/bit_mask/field.rb', line 5

def initialize(name, opts)
  @name = name
  @options = opts
  if !values.is_a?(Integer) && !values.is_a?(Array)
    raise "#{values.class} is an invalid class for values."
  end
end

Instance Attribute Details

#name ⇒ Object (readonly)

Returns the value of attribute name.



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# File 'lib/bit_mask/field.rb', line 2

def name
  @name
end

#options ⇒ Object (readonly)

Returns the value of attribute options.



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# File 'lib/bit_mask/field.rb', line 3

def options
  @options
end

Instance Method Details

#bits ⇒ Object 



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# File 'lib/bit_mask/field.rb', line 13

def bits
  @bits ||=
    if options[:bits]
      options[:bits]
    elsif values.kind_of?(Integer) && values < 0
      -1
    else
      if options[:limit]
        max_number = options[:limit]
      elsif values.is_a?(Integer)
        max_number = values
      elsif values.is_a?(Array)
        max_number = values.size
      end

      max_number += 1 if null

      (Math.log(max_number) / Math.log(2)).ceil
    end
end

#default ⇒ Object 



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# File 'lib/bit_mask/field.rb', line 42

def default
  @default ||=
    if null
      nil
    elsif values.kind_of? Integer
      0
    elsif values.respond_to? :first
      values.first
    elsif values.respond_to? :defaults
      values.defaults
    end
end

#from_i(value) ⇒ Object 



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# File 'lib/bit_mask/field.rb', line 67

def from_i(value)
  value -= 1 if self.null

  if self.null && value == -1
    value = nil
  elsif self.values.respond_to?(:at)
    value = self.values.at(value)
  end
  value
end

#null ⇒ Object 



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# File 'lib/bit_mask/field.rb', line 38

def null
  options[:null]
end

#to_bin(value) ⇒ Object 



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# File 'lib/bit_mask/field.rb', line 55

def to_bin(value)
  if self.null && value.nil?
    value = 0
  elsif self.values.respond_to? :index
    value = self.values.index(value)
    value += 1 if self.null
  end
  value = value.to_s(2)
  value = value.rjust(self.bits,'0') if self.bits > 0
  value
end

#values ⇒ Object 



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# File 'lib/bit_mask/field.rb', line 34

def values
  options[:values]
end