diffo

# SPDX-FileCopyrightText: 2025 diffo contributors <https://github.com/diffo-dev/diffo/graphs.contributors>
#
# SPDX-License-Identifier: MIT

defmodule Diffo.Provider.Feature do
  @moduledoc """
  Diffo - TMF Service and Resource Management with a difference

  Feature - Ash Resource for a TMF Feature
  """
  use Ash.Resource,
    otp_app: :diffo,
    domain: Diffo.Provider,
    data_layer: AshNeo4j.DataLayer,
    extensions: [AshOutstanding.Resource, AshJason.Resource]

  resource do
    description "An Ash Resource for a TMF Feature"
    plural_name :features
  end

  neo4j do
    relate [
      {:instance, :HAS, :incoming, :Instance},
      {:characteristics, :HAS, :outgoing, :Characteristic}
    ]

    guard [
      {:HAS, :incoming, :Instance}
    ]
  end

  jason do
    pick [:name, :isEnabled, :characteristics]

    customize fn result, _record ->
      result
      |> Diffo.Util.suppress_rename(:characteristics, :featureCharacteristic)
    end
  end

  outstanding do
    expect [:name, :isEnabled, :characteristics]
  end

  actions do
    defaults [:read, :destroy]

    create :create do
      description "creates a feature, optionally with related characteristic"
      accept [:name, :isEnabled]
      argument :characteristics, {:array, :uuid}

      change manage_relationship(:characteristics, type: :append)
    end

    read :find_by_name do
      description "finds features by name"
      get? false

      argument :query, :ci_string do
        description "Return only features with names including the given value."
      end

      filter expr(contains(name, ^arg(:query)))
    end

    read :list do
      description "lists all features"
    end

    update :update do
      primary? true
      description "updates the feature isEnabled or instance relationship"
      accept [:isEnabled]
      argument :instance_id, :uuid

      change manage_relationship(:instance_id, :instance, type: :append_and_remove)
    end

    update :relate_characteristics do
      description "relates characteristics to the feature"
      argument :characteristics, {:array, :uuid}
      change manage_relationship(:characteristics, type: :append)
    end

    update :unrelate_characteristics do
      description "unrelates characteristics from the feature"
      argument :characteristics, {:array, :uuid}
      change manage_relationship(:characteristics, type: :remove)
    end
  end

  attributes do
    uuid_primary_key :id do
      description "a uuid4, unique to this feature, generated by default"
      public? false
    end

    attribute :name, :atom do
      description "the name of this feature"
      allow_nil? false
      public? true
    end

    attribute :isEnabled, :boolean do
      description "indicates whether the feature is enabled"
      public? true
      default true
    end

    create_timestamp :created_at

    update_timestamp :updated_at
  end

  relationships do
    belongs_to :instance, Diffo.Provider.Instance do
      description "the instance the feature defines"
      allow_nil? true
      public? true
    end

    has_many :characteristics, Diffo.Provider.Characteristic do
      description "the feature's collection of defining characteristics"
      public? true
    end
  end

  identities do
    identity :instance_feature_uniqueness, [:instance_id, :name] do
      message "instance has duplicate feature"
      pre_check? true
    end
  end

  preparations do
    prepare build(load: [:characteristics], sort: [name: :asc])
  end

  @doc """
  Compares two feature, by ascending name
  ## Examples
    iex> Diffo.Provider.Feature.compare(%{name: "a"}, %{name: "a"})
    :eq
    iex> Diffo.Provider.Feature.compare(%{name: "b"}, %{name: "a"})
    :gt
    iex> Diffo.Provider.Feature.compare(%{name: "a"}, %{name: "b"})
    :lt

  """
  def compare(%{name: name0}, %{name: name1}), do: Diffo.Util.compare(name0, name1)
end