defmodule Bumblebee.Text.Gpt2Test do
  use ExUnit.Case, async: true

  import Bumblebee.TestHelpers

  @moduletag model_test_tags()

  test ":base" do
    assert {:ok, %{model: model, params: params, spec: spec}} =
             Bumblebee.load_model({:hf, "hf-internal-testing/tiny-random-GPT2Model"})

    assert %Bumblebee.Text.Gpt2{architecture: :base} = spec

    inputs = %{
      "input_ids" => Nx.tensor([[10, 20, 30, 40, 50, 60, 70, 80, 0, 0]]),
      "attention_mask" => Nx.tensor([[1, 1, 1, 1, 1, 1, 1, 1, 0, 0]])
    }

    outputs = Axon.predict(model, params, inputs)

    assert Nx.shape(outputs.hidden_state) == {1, 10, 32}

    assert_all_close(
      outputs.hidden_state[[.., 1..3, 1..3]],
      Nx.tensor([
        [[-0.8136, -0.2392, 0.2378], [0.9714, -0.4651, 0.8788], [-0.0980, 0.2294, -1.1416]]
      ])
    )
  end

  test ":for_causal_language_modeling" do
    assert {:ok, %{model: model, params: params, spec: spec}} =
             Bumblebee.load_model({:hf, "hf-internal-testing/tiny-random-GPT2LMHeadModel"})

    assert %Bumblebee.Text.Gpt2{architecture: :for_causal_language_modeling} = spec

    inputs = %{
      "input_ids" => Nx.tensor([[10, 20, 30, 40, 50, 60, 70, 80, 0, 0]]),
      "attention_mask" => Nx.tensor([[1, 1, 1, 1, 1, 1, 1, 1, 0, 0]])
    }

    outputs = Axon.predict(model, params, inputs)

    assert Nx.shape(outputs.logits) == {1, 10, 1024}

    assert_all_close(
      outputs.logits[[.., 1..3, 1..3]],
      Nx.tensor([
        [[0.1184, -0.0259, 0.1688], [0.1064, 0.1412, 0.1120], [0.1421, -0.2010, 0.3757]]
      ])
    )
  end

  test ":for_token_classification" do
    assert {:ok, %{model: model, params: params, spec: spec}} =
             Bumblebee.load_model(
               {:hf, "hf-internal-testing/tiny-random-GPT2ForTokenClassification"}
             )

    assert %Bumblebee.Text.Gpt2{architecture: :for_token_classification} = spec

    inputs = %{
      "input_ids" => Nx.tensor([[10, 20, 30, 40, 50, 60, 70, 80, 0, 0]]),
      "attention_mask" => Nx.tensor([[1, 1, 1, 1, 1, 1, 1, 1, 0, 0]])
    }

    outputs = Axon.predict(model, params, inputs)

    assert Nx.shape(outputs.logits) == {1, 10, 2}

    assert_all_close(
      outputs.logits[[.., 1..3//1, ..]],
      Nx.tensor([[[0.0207, 0.1338], [-0.1582, -0.0384], [-0.2225, -0.0400]]])
    )
  end

  test ":for_sequence_classification" do
    assert {:ok, %{model: model, params: params, spec: spec}} =
             Bumblebee.load_model(
               {:hf, "hf-internal-testing/tiny-random-GPT2ForSequenceClassification"}
             )

    assert %Bumblebee.Text.Gpt2{architecture: :for_sequence_classification} = spec

    inputs = %{
      "input_ids" => Nx.tensor([[10, 20, 30, 40, 50, 60, 70, 80, 1023, 1023]]),
      "attention_mask" => Nx.tensor([[1, 1, 1, 1, 1, 1, 1, 1, 0, 0]])
    }

    outputs = Axon.predict(model, params, inputs)

    assert Nx.shape(outputs.logits) == {1, 2}

    assert_all_close(
      outputs.logits,
      Nx.tensor([[-0.0098, -0.0456]])
    )
  end
end
