# Defines the relations between ActiveRepository objects.
#
# Author::    Caio Torres  (mailto:efreesen@gmail.com)
# License::   GPL

module ActiveRepository
  module Associations
    def self.included(base)
      base.extend Methods
    end

    module Methods
      # Defines "has many" type relation between ActiveRepository objects
      def has_many(association_id, options = {})
        define_method(association_id) do
          options = {
            class_name:  association_id.to_s.classify,
            foreign_key: self.class.to_s.foreign_key
          }.merge(options)

          klass = options[:class_name].constantize
          objects = []

          klass.where(options[:foreign_key] => id)
        end
      end

      # Defines "has one" type relation between ActiveRepository objects
      def has_one(association_id, options = {})
        define_method(association_id) do
          options = {
            class_name:  association_id.to_s.classify,
            foreign_key: self.class.to_s.foreign_key
          }.merge(options)

          scope = options[:class_name].constantize

          scope = scope.where(options[:conditions]) if options[:conditions]

          send_params = scope.respond_to?(:find_by) ? ["find_by", id: id] : ["find_by_id", id]

          scope.send(*send_params)
        end
      end

      # Defines "belongs to" type relation between ActiveRepository objects
      def belongs_to(association_id, options = {})
        options = {
          class_name:  association_id.to_s.classify,
          foreign_key: association_id.to_s.foreign_key
        }.merge(options)

        field options[:foreign_key].to_sym

        define_method(association_id) do
          klass = options[:class_name].constantize
          id    = send(options[:foreign_key])

          if id.present?
            object = klass.respond_to?(:find_by) ? klass.find_by(id: id) : klass.find_by_id(id)
          else
            nil
          end
        end

        define_method("#{association_id}=") do |new_value|
          attributes.delete(association_id.to_sym)
          send("#{options[:foreign_key]}=", (new_value.try(:id) ? new_value.id : new_value))
        end
      end
    end
  end
end