defmodule Mv.Accounts.User do
  @moduledoc """
  The ressource for keeping user-specific data related to the login process. It is used by AshAuthentication to handle the Authentication strategies like SSO.
  """
  use Ash.Resource,
    domain: Mv.Accounts,
    data_layer: AshPostgres.DataLayer,
    extensions: [AshAuthentication]

  # authorizers: [Ash.Policy.Authorizer]

  postgres do
    table "users"
    repo Mv.Repo
  end

  @doc """
  AshAuthentication specific: Defines the strategies we want to use for authentication.
  Currently password and SSO with Rauthy as OIDC provider
  """
  authentication do
    session_identifier Application.get_env(:mv, :session_identifier)

    tokens do
      enabled? true
      token_resource Mv.Accounts.Token

      require_token_presence_for_authentication? Application.get_env(
                                                   :mv,
                                                   :require_token_presence_for_authentication
                                                 )

      store_all_tokens? true

      # signing_algorithm "EdDSA" -> https://git.local-it.org/local-it/mitgliederverwaltung/issues/87

      signing_secret fn _, _ ->
        {:ok, Application.get_env(:mv, :token_signing_secret)}
      end
    end

    strategies do
      oidc :rauthy do
        client_id Mv.Secrets
        base_url Mv.Secrets
        redirect_uri Mv.Secrets
        client_secret Mv.Secrets
        auth_method :client_secret_jwt
        code_verifier true

        # id_token_signed_response_alg "EdDSA" #-> https://git.local-it.org/local-it/mitgliederverwaltung/issues/87
      end

      password :password do
        identity_field :email
        hash_provider AshAuthentication.BcryptProvider
        confirmation_required? false
      end
    end
  end

  actions do
    defaults [:read, :create, :destroy, :update]

    read :get_by_subject do
      description "Get a user by the subject claim in a JWT"
      argument :subject, :string, allow_nil?: false
      get? true
      prepare AshAuthentication.Preparations.FilterBySubject
    end

    read :sign_in_with_rauthy do
      argument :user_info, :map, allow_nil?: false
      argument :oauth_tokens, :map, allow_nil?: false
      prepare AshAuthentication.Strategy.OAuth2.SignInPreparation

      filter expr(email == get_path(^arg(:user_info), [:email]))
    end

    create :register_with_rauthy do
      argument :user_info, :map, allow_nil?: false
      argument :oauth_tokens, :map, allow_nil?: false
      upsert? true
      upsert_identity :unique_email

      change AshAuthentication.GenerateTokenChange

      change fn changeset, _ctx ->
        user_info = Ash.Changeset.get_argument(changeset, :user_info)

        changeset
        |> Ash.Changeset.change_attribute(:email, user_info["preferred_username"])
        |> Ash.Changeset.change_attribute(:oidc_id, user_info["id"])
      end
    end
  end

  attributes do
    uuid_primary_key :id

    attribute :email, :ci_string, allow_nil?: false, public?: true
    attribute :hashed_password, :string, sensitive?: true, allow_nil?: true
    attribute :oidc_id, :string, allow_nil?: true
  end

  relationships do
    belongs_to :member, Mv.Membership.Member
  end

  identities do
    identity :unique_email, [:email]
    identity :unique_oidc_id, [:oidc_id]
  end

  # You can customize this if you wish, but this is a safe default that
  # only allows user data to be interacted with via AshAuthentication.
  # policies do
  #   bypass AshAuthentication.Checks.AshAuthenticationInteraction do
  #     authorize_if(always())
  #   end

  #   policy always() do
  #     forbid_if(always())
  #   end
  # end
end