Module: Nostalgic::NostalgicAttr::ClassMethods

Defined in:
lib/nostalgic/nostalgic_attr.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#nostalgic_attrs ⇒ Object

Returns the value of attribute nostalgic_attrs.



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# File 'lib/nostalgic/nostalgic_attr.rb', line 39

def nostalgic_attrs
  @nostalgic_attrs
end

Instance Method Details

#belongs_to(name, scope = nil, options = {}) ⇒ Object 



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# File 'lib/nostalgic/nostalgic_attr.rb', line 41

def belongs_to(name, scope = nil, options = {})
  scope ||= {}
  super(name, scope.except(:nostalgic), options)

  if scope.fetch(:nostalgic, false)
    foreign_key = options.fetch(:foreign_key, "#{name}_id")
    nostalgic_attr foreign_key

    class_eval <<-METHODS, __FILE__, __LINE__ + 1
      def #{name}_on(date)
        return self.#{name} unless date.present?

        '#{name}'.classify.constantize.find_by_id(#{foreign_key}_on(date))
      end

      alias_method :#{name}_at, :#{name}_on
    METHODS
  end
end

#nostalgic_attr(*attrs) ⇒ Object 



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# File 'lib/nostalgic/nostalgic_attr.rb', line 61

def nostalgic_attr(*attrs)
  self.nostalgic_attrs ||= []

  attrs.each do |attr|
    next if self.nostalgic_attrs.include?(attr.to_sym)
    self.nostalgic_attrs << attr.to_sym

    model_type = self.model_name.to_s

    class_eval <<-METHODS, __FILE__, __LINE__ + 1
      has_many :#{attr.to_s.pluralize}, -> {where(:model_type => model_type, :name => '#{attr}').order('effective_at desc')}, :class_name => 'Nostalgic::Attr', :foreign_key => 'model_id'
      accepts_nested_attributes_for :#{attr.to_s.pluralize}, :allow_destroy => true

      attr_accessor :#{attr}_effective_at

      def #{attr}_on(date)
        return self.#{attr} unless date.present?

        na = Nostalgic::Attr.where(:model_type => self.class.name, :model_id => self.id, :name => '#{attr}')
        na = na.where('effective_at <= ?', date).order('effective_at desc').first
        na ? na.value : self.#{attr}
      end

      alias_method :#{attr}_at, :#{attr}_on
    METHODS
  end
end