Contents

module HoboFields
  
  class FieldSpec
    
    class UnknownSqlTypeError < RuntimeError; end
  
    def initialize(model, name, type, options={})
      raise ArgumentError, "you cannot provide a field spec for the primary key" if name == model.primary_key
      self.model = model
      self.name = name.to_sym
      self.type = type.is_a?(String) ? type.to_sym : type
      self.options = options
      self.position = model.field_specs.length
    end
    
    attr_accessor :model, :name, :type, :position, :options
    
    def sql_type
      options[:sql_type] or begin
                              if native_type?(type)
                                type
                              else
                                field_class = HoboFields.to_class(type)
                                field_class && field_class::COLUMN_TYPE or raise UnknownSqlTypeError, "#{model}.#{name}::#{type}"
                              end
                            end
    end
    
    def limit
      options[:limit] || native_types[sql_type][:limit]
    end
    
    def precision
      options[:precision]
    end
    
    def scale
      options[:scale]
    end
    
    def null
      :null.in?(options) ? options[:null] : true
    end
    
    def default
      options[:default]
    end
    
    def different_to?(col_spec)
      sql_type != col_spec.type ||
        begin
          check_cols = [:null, :default]
          check_cols += [:precision, :scale] if sql_type == :decimal
          check_cols << :limit if sql_type.in?([:string, :text, :binary, :integer])
          check_cols.any? { |k| col_spec.send(k) != self.send(k) }
        end
    end
    
    
    private
    
    def native_type?(type)
      type.in?(native_types.keys - [:primary_key])
    end
    
    def native_types
      model.connection.native_database_types
    end
    
  end
  
end

Version data entries

1 entries across 1 versions & 1 rubygems

Version	Path
hobofields-0.7.5	lib/hobo_fields/field_spec.rb