SpeciesFileGroup/taxonworks

module Vendor

  # Functions for Papertrail
  module Papertrail 

    # @Return [Hash, false] a summary of the differences in two versions of the object
    # @param object [Obect] any instance of an IsData class
    # @param verstion_a [String|Integer] papertrail index of a version to compare
    # @param verstion_b [String|Integer] papertrail index of a version to compare
    def self.compare(object, opts = {} )
      r = {
        object: object,
        comparing_current: false,
        version_a: opts[:version_a].to_i,
        version_b: opts[:version_b].to_i,
        attributes_new: {},
        attributes_old: {},
        user_new: nil,
        user_old: nil
      }

      version_index_a = r[:version_a] # version_a.to_i #params.require(:version_a).to_i
      version_index_b = r[:version_b] # version_b.to_i #params.require(:version_b).to_i

      # The version at index 0 is the version created before something is made,
      # as in the state of the obj before it was created, aka all attributes null
      # thus why index of 1 (when it actually has attributes) is the smallest
      # an index can be for a proper version
      if version_index_a < 0 || version_index_a >= object.versions.length
        return false
      end

      # If version_b index is outside the range treat it as if it means that
      # we should compare the current version to an older version, thus set it
      # equal to version_a index for simplicity for later on
      if version_index_b <= 0 || version_index_b >= object.versions.length
        version_index_b = version_index_a;
      end

      # Make version_index_a be an index to the newer version
      # thus if version_index_b is greater than version_index_a
      # we must swap the two values to make version_index_a
      # an index to the newer version
      if version_index_b > version_index_a
        tmp_version_index = version_index_b
        version_index_b = version_index_a
        version_index_a = tmp_version_index
      end

      # version_a will point to the newer version
      # version_b will pointvto the older version
      version_a = object.versions[version_index_a]
      version_b = object.versions[version_index_b]

      r[:attributes_new] = version_a.reify.attributes
      r[:attributes_old] = version_b.reify.attributes
      r[:comparing_current] = false

      # If the index for version_a and version_b match it means
      # we're comparing the current version against an older one
      if(version_index_a == version_index_b)
#         r[:user_new] = User.find(object['updated_by_id']).name  # wrong!
#         r[:user_old] = User.find(r[:attributes_old]['updated_by_id']).name  # wrong!
        r[:attributes_new] = object.attributes
        r[:comparing_current] = true
      end

      r[:user_new] = User.find(version_a.whodunnit).name
      r[:user_old] = User.find(version_b.whodunnit).name

      r[:index_old] = version_index_a
      r[:index_new] = version_index_b

  #   r[:attributes_new] = view_context.filter_out_attributes(r[:attributes_new])
  #   r[:attributes_old] = view_context.filter_out_attributes(r[:attributes_old])

      r


    end

  end
end