ash_dispatch

defmodule AshDispatch.Setup do
  @moduledoc """
  Automatically sets up DeliveryReceipt resource in your consuming app.

  Similar to ash_paper_trail, this creates the necessary resources for you with
  zero manual module creation needed.

  ## Usage

  In your Deliveries domain module:

      defmodule MyApp.Deliveries do
        use AshDispatch.Setup,
          repo: MyApp.Repo,
          user_resource: MyApp.Accounts.User

        # Your domain definition continues here...
        use Ash.Domain
        # ... rest of domain config
      end

  This will automatically create `MyApp.Deliveries.DeliveryReceipt` with the
  user relationship - completely frictionless!
  """

  defmacro __using__(opts) do
    repo = Keyword.fetch!(opts, :repo)
    user_resource = Keyword.fetch!(opts, :user_resource)

    # Build the complete resource module AST
    delivery_receipt_ast = build_delivery_receipt_ast(repo, user_resource)

    quote do
      # Get the calling module to namespace the DeliveryReceipt
      caller_module = __MODULE__
      receipt_module = Module.concat(caller_module, DeliveryReceipt)

      # Dynamically create the DeliveryReceipt resource
      Module.create(receipt_module, unquote(delivery_receipt_ast), Macro.Env.location(__ENV__))
    end
  end

  defp build_delivery_receipt_ast(repo, user_resource) do
    # `ash_typescript` is optional, and this used to name `AshTypescript.Resource`
    # unconditionally — so `use AshDispatch.Setup` failed to compile in any app
    # without it, whatever `--no-typescript` said (#31). Checked here, at macro
    # expansion in the consuming app, so the extension follows *that* app's
    # deps. Apps that do have it keep a TypeScript-enabled receipt, as before.
    extensions =
      if Code.ensure_loaded?(AshTypescript.Resource),
        do: [AshStateMachine, AshTypescript.Resource],
        else: [AshStateMachine]

    quote do
      @moduledoc """
      Delivery receipt tracking resource.

      Auto-generated by AshDispatch.Setup - tracks all message deliveries
      (email, in-app, Discord, SMS, etc.) with full audit trail.
      """

      use Ash.Resource,
        data_layer: AshPostgres.DataLayer,
        authorizers: [Ash.Policy.Authorizer],
        extensions: unquote(extensions)

      postgres do
        table "delivery_receipts"
        repo(unquote(repo))

        references do
          reference(:notification, on_delete: :nilify)
          reference(:user, on_delete: :nilify)
        end
      end

      state_machine do
        initial_states([:pending])
        default_initial_state(:pending)
        state_attribute(:status)
        extra_states([:sending, :sent, :failed_permanent, :skipped, :scheduled, :failed])

        transitions do
          transition(:schedule, from: :pending, to: :scheduled)
          transition(:mark_sending, from: [:scheduled, :pending], to: :sending)
          transition(:mark_sent, from: [:sending, :scheduled, :pending], to: :sent)
          transition(:mark_failed, from: [:sending, :scheduled, :pending], to: :failed)

          transition(:mark_failed_permanent,
            from: [:sending, :scheduled, :failed],
            to: :failed_permanent
          )

          transition(:skip, from: [:pending, :scheduled, :sending], to: :skipped)
          transition(:retry, from: :failed, to: :scheduled)
        end
      end

      relationships do
        belongs_to :notification, AshDispatch.Resources.Notification do
          source_attribute :notification_id
          destination_attribute :id
          allow_nil? true
          public? true
          define_attribute? false
        end

        # User relationship - works because we're compiling in the consuming app!
        belongs_to :user, unquote(user_resource) do
          source_attribute :user_id
          destination_attribute :id
          allow_nil? true
          public? true
          define_attribute? false
        end
      end

      attributes do
        uuid_primary_key :id

        attribute :event_id, :string, allow_nil?: false, public?: true

        # Derived from the transport registry rather than hardcoded: this list
        # and the one in DeliveryReceipt.Base had already drifted apart (this
        # one was missing `:slack`), so a new transport could produce receipts
        # the resource refused to accept.
        attribute :transport, :atom,
          allow_nil?: false,
          public?: true,
          constraints: [one_of: AshDispatch.Transport.Registry.receipted_atoms()]

        attribute :user_id, :uuid, allow_nil?: true, public?: true
        attribute :notification_id, :uuid, allow_nil?: true, public?: true

        attribute :audience, :atom,
          allow_nil?: false,
          public?: true,
          constraints: [one_of: [:user, :admin, :system]]

        attribute :status, :atom,
          default: :pending,
          allow_nil?: false,
          public?: true,
          constraints: [
            one_of: [:pending, :scheduled, :sending, :sent, :failed, :failed_permanent, :skipped]
          ]

        attribute :recipient, :string, allow_nil?: false, public?: true
        attribute :provider_id, :string, allow_nil?: true, public?: true
        attribute :provider_response, :map, default: %{}, allow_nil?: false, public?: true
        attribute :subject, :string, allow_nil?: true, public?: true
        attribute :body_text, :string, allow_nil?: true, public?: true
        attribute :body_html, :string, allow_nil?: true, public?: true
        attribute :content, :map, default: %{}, allow_nil?: false, public?: true
        attribute :oban_job_id, :integer, allow_nil?: true, public?: true
        attribute :error_message, :string, allow_nil?: true, public?: true
        attribute :retry_count, :integer, default: 0, allow_nil?: false, public?: true
        attribute :last_retry_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :sent_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :delivered_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :delivery_delayed_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :failed_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :opened_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :clicked_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :bounced_at, :utc_datetime_usec, allow_nil?: true, public?: true
        attribute :complained_at, :utc_datetime_usec, allow_nil?: true, public?: true

        create_timestamp :inserted_at
        update_timestamp :updated_at
      end

      calculations do
        calculate :oban_job, :map, {AshDispatch.Calculations.ObanJob, []} do
          public? true
        end
      end

      actions do
        default_accept :*
        defaults [:read, :destroy]

        create :create do
          accept [
            :event_id,
            :transport,
            :user_id,
            :notification_id,
            :audience,
            :recipient,
            :subject,
            :body_text,
            :body_html,
            :content,
            :oban_job_id,
            :provider_id,
            :provider_response
          ]
        end

        read :list_all do
          pagination offset?: true, keyset?: true, required?: false
        end

        read :list_for_user do
          argument :user_id, :uuid, allow_nil?: false
          filter expr(user_id == ^arg(:user_id))
          pagination offset?: true, keyset?: true, required?: false
        end

        read :get do
          argument :id, :uuid, allow_nil?: false
          get? true
          filter expr(id == ^arg(:id))
        end

        update :schedule do
          accept [:oban_job_id]
          change transition_state(:scheduled)
        end

        update :mark_sending do
          change transition_state(:sending)
        end

        update :mark_sent do
          accept [:sent_at]
          change transition_state(:sent)
        end

        update :mark_failed do
          accept [:error_message]
          change transition_state(:failed)
          change increment(:retry_count, amount: 1)
        end

        update :mark_failed_permanent do
          accept [:error_message]
          change transition_state(:failed_permanent)
        end

        update :skip do
          change transition_state(:skipped)
        end

        update :retry do
          accept [:oban_job_id]
          change transition_state(:scheduled)
        end
      end

      policies do
        policy always() do
          authorize_if always()
        end
      end

      identities do
        identity :oban_job, [:oban_job_id]
        identity :notification, [:notification_id]
      end
    end
  end
end