neiam /gitgud

defmodule GitGud.Accounts.PersonalAccessToken do
  @moduledoc """
  A user-scoped API token (`ggp_…`) for the REST API. Only the SHA-256
  `token_hash` is stored; the plaintext is shown once at creation.

  `scopes` is a subset of the extensible vocabulary in `scopes/0`. The
  API authorizes each request against the required scope, so new scopes
  can be added here over time without changing existing tokens. Today:

    * `repo` — create / manage repositories
  """
  use Ecto.Schema

  import Ecto.Changeset

  alias GitGud.Accounts.User

  # Extend this list to add scopes; tokens are validated against it.
  @scopes ~w(repo)

  schema "personal_access_tokens" do
    field :name, :string
    field :token_hash, :binary, redact: true
    field :scopes, {:array, :string}, default: []
    field :last_used_at, :utc_datetime

    belongs_to :user, User

    timestamps(type: :utc_datetime)
  end

  @doc false
  def changeset(token, attrs) do
    token
    |> cast(attrs, [:name, :token_hash, :scopes, :user_id])
    |> validate_required([:name, :token_hash, :user_id])
    |> validate_length(:name, min: 1, max: 100)
    |> validate_subset(:scopes, @scopes)
    |> validate_length(:scopes, min: 1)
    |> unique_constraint(:name, name: :personal_access_tokens_user_id_name_index)
    |> unique_constraint(:token_hash)
  end

  @doc "The set of scopes a token may carry."
  def scopes, do: @scopes
end