# Pleroma: A lightweight social networking server
# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
# SPDX-License-Identifier: AGPL-3.0-only

defmodule Pleroma.PasswordResetToken do
  use Ecto.Schema

  import Ecto.Changeset

  alias Pleroma.PasswordResetToken
  alias Pleroma.Repo
  alias Pleroma.User

  schema "password_reset_tokens" do
    belongs_to(:user, User, type: FlakeId.Ecto.CompatType)
    field(:token, :string)
    field(:used, :boolean, default: false)

    timestamps()
  end

  def create_token(%User{} = user) do
    token = :crypto.strong_rand_bytes(32) |> Base.url_encode64()

    token = %PasswordResetToken{
      user_id: user.id,
      used: false,
      token: token
    }

    Repo.insert(token)
  end

  def used_changeset(struct) do
    struct
    |> cast(%{}, [])
    |> put_change(:used, true)
  end

  @spec reset_password(binary(), map()) :: {:ok, User.t()} | {:error, binary()}
  def reset_password(token, data) do
    with %{used: false} = token <- Repo.get_by(PasswordResetToken, %{token: token}),
         false <- expired?(token),
         %User{} = user <- User.get_cached_by_id(token.user_id),
         {:ok, _user} <- User.reset_password(user, data),
         {:ok, token} <- Repo.update(used_changeset(token)) do
      {:ok, token}
    else
      _e -> {:error, token}
    end
  end

  def expired?(%__MODULE__{inserted_at: inserted_at}) do
    validity = Pleroma.Config.get([:instance, :password_reset_token_validity], 0)

    now = NaiveDateTime.utc_now()

    difference = NaiveDateTime.diff(now, inserted_at)

    difference > validity
  end
end
