defmodule AI do
  @moduledoc """
  AI is a behavior module that defines the interface for interacting with
  OpenAI's API. It provides a common interface for the various OpenAI-powered
  operations used by the application.
  """

  defstruct [
    :client,
    :api_key
  ]

  @type t :: %__MODULE__{
          client: %OpenaiEx{}
        }

  @api_timeout 45_000

  @callback new() :: struct()
  @callback get_embeddings(struct(), String.t()) :: {:ok, [String.t()]} | {:error, term()}
  @callback get_summary(struct(), String.t(), String.t()) :: {:ok, String.t()} | {:error, term()}

  @behaviour AI

  @impl AI
  @doc """
  Create a new AI instance. Instances share the same client connection.
  """
  def new() do
    api_key = System.get_env("OPENAI_API_KEY")

    if is_nil(api_key) do
      raise "Missing OpenAI API key. Please set the OPENAI_API_KEY environment variable."
    end

    openai =
      api_key
      |> OpenaiEx.new()
      |> OpenaiEx.with_receive_timeout(@api_timeout)

    %AI{client: openai}
  end

  # -----------------------------------------------------------------------------
  # Embeddings
  # -----------------------------------------------------------------------------
  @impl AI
  @doc """
  See `AI.EmbeddingsAgent.get_embeddings/2`.
  """
  defdelegate get_embeddings(ai, text), to: AI.Agent.Embeddings

  # -----------------------------------------------------------------------------
  # Summaries
  # -----------------------------------------------------------------------------
  @impl AI
  @doc """
  See `AI.FileSummaryAgent.get_summary/3`.
  """
  defdelegate get_summary(ai, file, text), to: AI.Agent.FileSummary
end