# Copyright 2021 The HuggingFace Team. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import inspect
import math
import multiprocessing
import unittest

import numpy as np
from datasets import load_dataset

from transformers import Wav2Vec2Config, is_flax_available
from transformers.testing_utils import (
    CaptureLogger,
    is_flaky,
    is_librosa_available,
    is_pt_flax_cross_test,
    is_pyctcdecode_available,
    require_flax,
    require_librosa,
    require_pyctcdecode,
    require_soundfile,
    slow,
)

from ...test_modeling_flax_common import FlaxModelTesterMixin, floats_tensor, random_attention_mask


if is_flax_available():
    import jax
    import jax.numpy as jnp
    import optax
    from flax.traverse_util import flatten_dict
    from transformers import Wav2Vec2FeatureExtractor, Wav2Vec2Processor
    from transformers.models.wav2vec2.modeling_flax_wav2vec2 import (
        FlaxWav2Vec2ForCTC,
        FlaxWav2Vec2ForPreTraining,
        FlaxWav2Vec2GumbelVectorQuantizer,
        FlaxWav2Vec2Model,
        _compute_mask_indices,
        _sample_negative_indices,
    )


if is_pyctcdecode_available():
    from transformers import Wav2Vec2ProcessorWithLM
    from transformers.models.wav2vec2_with_lm import processing_wav2vec2_with_lm


if is_librosa_available():
    import librosa


class FlaxWav2Vec2ModelTester:
    def __init__(
        self,
        parent,
        batch_size=13,
        seq_length=1024,  # speech is longer
        is_training=False,
        hidden_size=24,
        feat_extract_norm="layer",
        feat_extract_dropout=0.0,
        feat_extract_activation="gelu",
        conv_dim=(32, 32, 32),
        conv_stride=(4, 4, 4),
        conv_kernel=(8, 8, 8),
        conv_bias=False,
        num_conv_pos_embeddings=16,
        num_conv_pos_embedding_groups=2,
        num_hidden_layers=4,
        num_attention_heads=2,
        hidden_dropout_prob=0.1,  # this is most likely not correctly set yet
        intermediate_size=20,
        layer_norm_eps=1e-5,
        hidden_act="gelu",
        initializer_range=0.02,
        vocab_size=32,
        do_stable_layer_norm=True,
        scope=None,
    ):
        self.parent = parent
        self.batch_size = batch_size
        self.seq_length = seq_length
        self.is_training = is_training
        self.hidden_size = hidden_size
        self.feat_extract_norm = feat_extract_norm
        self.feat_extract_dropout = feat_extract_dropout
        self.feat_extract_activation = feat_extract_activation
        self.conv_dim = conv_dim
        self.conv_stride = conv_stride
        self.conv_kernel = conv_kernel
        self.conv_bias = conv_bias
        self.num_conv_pos_embeddings = num_conv_pos_embeddings
        self.num_conv_pos_embedding_groups = num_conv_pos_embedding_groups
        self.num_hidden_layers = num_hidden_layers
        self.num_attention_heads = num_attention_heads
        self.hidden_dropout_prob = hidden_dropout_prob
        self.intermediate_size = intermediate_size
        self.layer_norm_eps = layer_norm_eps
        self.hidden_act = hidden_act
        self.initializer_range = initializer_range
        self.vocab_size = vocab_size
        self.do_stable_layer_norm = do_stable_layer_norm
        self.scope = scope

        output_seq_length = self.seq_length
        for kernel, stride in zip(self.conv_kernel, self.conv_stride):
            output_seq_length = (output_seq_length - (kernel - 1)) / stride
        self.output_seq_length = int(math.ceil(output_seq_length))
        self.encoder_seq_length = self.output_seq_length

    def prepare_config_and_inputs(self):
        input_values = floats_tensor([self.batch_size, self.seq_length], scale=1.0)
        attention_mask = random_attention_mask([self.batch_size, self.seq_length])

        config = Wav2Vec2Config(
            do_stable_layer_norm=self.do_stable_layer_norm,
            hidden_size=self.hidden_size,
            feat_extract_norm=self.feat_extract_norm,
            feat_extract_dropout=self.feat_extract_dropout,
            feat_extract_activation=self.feat_extract_activation,
            conv_dim=self.conv_dim,
            conv_stride=self.conv_stride,
            conv_kernel=self.conv_kernel,
            conv_bias=self.conv_bias,
            num_conv_pos_embeddings=self.num_conv_pos_embeddings,
            num_conv_pos_embedding_groups=self.num_conv_pos_embedding_groups,
            num_hidden_layers=self.num_hidden_layers,
            num_attention_heads=self.num_attention_heads,
            hidden_dropout_prob=self.hidden_dropout_prob,
            intermediate_size=self.intermediate_size,
            layer_norm_eps=self.layer_norm_eps,
            hidden_act=self.hidden_act,
            initializer_range=self.initializer_range,
            vocab_size=self.vocab_size,
        )

        return config, input_values, attention_mask

    def prepare_config_and_inputs_for_common(self):
        config_and_inputs = self.prepare_config_and_inputs()
        config, input_values, attention_mask = config_and_inputs
        inputs_dict = {"input_values": input_values, "attention_mask": attention_mask}
        return config, inputs_dict


@require_flax
class FlaxWav2Vec2ModelTest(FlaxModelTesterMixin, unittest.TestCase):
    all_model_classes = (
        (FlaxWav2Vec2Model, FlaxWav2Vec2ForCTC, FlaxWav2Vec2ForPreTraining) if is_flax_available() else ()
    )

    def setUp(self):
        self.model_tester = FlaxWav2Vec2ModelTester(self)

    def test_train(self):
        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()

        input_values = inputs_dict["input_values"]
        attention_mask = inputs_dict["attention_mask"]

        model = FlaxWav2Vec2ForPreTraining(config)

        features_shape = (
            input_values.shape[0],
            model._get_feat_extract_output_lengths(np.array(input_values.shape[1])),
        )

        batch_size, sequence_length = features_shape[:2]

        mask_prob = 0.5
        mask_length = 4
        mask_time_indices = _compute_mask_indices((batch_size, sequence_length), mask_prob, mask_length)

        dropout_rng, gumbel_rng = jax.random.split(jax.random.PRNGKey(0))

        output = model(
            input_values,
            attention_mask=attention_mask,
            mask_time_indices=mask_time_indices,
            train=True,
            dropout_rng=dropout_rng,
            gumbel_rng=gumbel_rng,
        )[0]

        self.assertTrue(output.shape == (batch_size, sequence_length, model.config.proj_codevector_dim))

    # overwrite because of `input_values`
    def test_forward_signature(self):
        config, _ = self.model_tester.prepare_config_and_inputs_for_common()

        for model_class in self.all_model_classes:
            model = model_class(config)
            signature = inspect.signature(model.__call__)
            # signature.parameters is an OrderedDict => so arg_names order is deterministic
            arg_names = [*signature.parameters.keys()]

            expected_arg_names = ["input_values", "attention_mask"]
            self.assertListEqual(arg_names[:2], expected_arg_names)

    # overwrite because of `input_values`
    def test_jit_compilation(self):
        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()

        for model_class in self.all_model_classes:
            with self.subTest(model_class.__name__):
                prepared_inputs_dict = self._prepare_for_class(inputs_dict, model_class)
                model = model_class(config)

                @jax.jit
                def model_jitted(input_values, attention_mask=None, **kwargs):
                    return model(input_values=input_values, attention_mask=attention_mask, **kwargs)

                with self.subTest("JIT Enabled"):
                    jitted_outputs = model_jitted(**prepared_inputs_dict).to_tuple()

                with self.subTest("JIT Disabled"):
                    with jax.disable_jit():
                        outputs = model_jitted(**prepared_inputs_dict).to_tuple()

                self.assertEqual(len(outputs), len(jitted_outputs))
                for jitted_output, output in zip(jitted_outputs, outputs):

                    self.assertEqual(jitted_output.shape, output.shape)

    def test_freeze_feature_encoder(self):
        config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()

        input_values = inputs_dict["input_values"]
        attention_mask = inputs_dict["attention_mask"]

        model = FlaxWav2Vec2ForPreTraining(config)
        params = model.params

        # dummy loss function
        def compute_loss(
            params, input_values, attention_mask, freeze_feature_encoder: bool = False, epsilon: float = 1e-8
        ):
            outputs = model(
                input_values,
                attention_mask=attention_mask,
                freeze_feature_encoder=freeze_feature_encoder,
                params=params,
            )
            # compute cosine similarity of projected and projected_quantized states
            cosine_sim = optax.cosine_similarity(
                outputs.projected_states, outputs.projected_quantized_states, epsilon=epsilon
            )
            loss = cosine_sim.sum()
            return loss, outputs.to_tuple()

        # transform the loss function to get the gradients
        grad_fn = jax.value_and_grad(compute_loss, has_aux=True)

        # compute loss, outputs and gradients for unfrozen model
        (loss, outputs), grads = grad_fn(params, input_values, attention_mask, freeze_feature_encoder=False)

        # compare to loss, outputs and gradients for frozen model
        (loss_frozen, outputs_frozen), grads_frozen = grad_fn(
            params, input_values, attention_mask, freeze_feature_encoder=True
        )

        # ensure that the outputs and losses remain precisely equal
        for output, output_frozen in zip(outputs, outputs_frozen):
            self.assertTrue((output == output_frozen).all())
        self.assertEqual(loss, loss_frozen)

        grads = flatten_dict(grads)
        grads_frozen = flatten_dict(grads_frozen)

        # ensure that the dicts of gradients contain the same keys
        self.assertEqual(grads.keys(), grads_frozen.keys())

        # ensure that the gradients of the feature extractor layers are precisely zero when frozen and contain non-zero entries when unfrozen
        feature_extractor_grads = tuple(grads[k] for k in grads if "feature_extractor" in k)
        feature_extractor_grads_frozen = tuple(grads_frozen[k] for k in grads_frozen if "feature_extractor" in k)

        for feature_extractor_grad, feature_extractor_grad_frozen in zip(
            feature_extractor_grads, feature_extractor_grads_frozen
        ):
            self.assertTrue((feature_extractor_grad_frozen == 0.0).all())
            self.assertTrue((feature_extractor_grad > 0.0).any())

        # ensure that the gradients of all unfrozen layers remain equal, i.e. all layers excluding the frozen 'feature_extractor'
        grads = tuple(grads[k] for k in grads if "feature_extractor" not in k)
        grads_frozen = tuple(grads_frozen[k] for k in grads_frozen if "feature_extractor" not in k)

        for grad, grad_frozen in zip(grads, grads_frozen):
            self.assertTrue((grad == grad_frozen).all())

    @slow
    def test_model_from_pretrained(self):
        for model_class_name in self.all_model_classes:
            model = model_class_name.from_pretrained("facebook/wav2vec2-large-960h-lv60-self", from_pt=True)
            outputs = model(np.ones((1, 1024), dtype="f4"))
            self.assertIsNotNone(outputs)

    @is_pt_flax_cross_test
    @is_flaky()
    def test_equivalence_pt_to_flax(self):
        super().test_equivalence_pt_to_flax()


@require_flax
class FlaxWav2Vec2UtilsTest(unittest.TestCase):
    def test_compute_mask_indices(self):
        batch_size = 4
        sequence_length = 60
        mask_prob = 0.5
        mask_length = 1

        mask = _compute_mask_indices((batch_size, sequence_length), mask_prob, mask_length)

        self.assertListEqual(mask.sum(axis=-1).tolist(), [mask_prob * sequence_length for _ in range(batch_size)])

    def test_compute_mask_indices_overlap(self):
        batch_size = 4
        sequence_length = 80
        mask_prob = 0.5
        mask_length = 4

        mask = _compute_mask_indices((batch_size, sequence_length), mask_prob, mask_length)

        # because of overlap mask don't have to add up exactly to `mask_prob * sequence_length`, but have to be smaller or equal
        for batch_sum in mask.sum(axis=-1):
            self.assertTrue(int(batch_sum) <= mask_prob * sequence_length)

    def test_compute_mask_indices_attn_mask_overlap(self):
        batch_size = 4
        sequence_length = 80
        mask_prob = 0.5
        mask_length = 4

        attention_mask = np.ones((batch_size, sequence_length), dtype=np.int32)
        attention_mask[:2, sequence_length // 2 :] = 0

        mask = _compute_mask_indices(
            (batch_size, sequence_length), mask_prob, mask_length, attention_mask=attention_mask
        )

        for batch_sum in mask.sum(axis=-1):
            self.assertTrue(int(batch_sum) <= mask_prob * sequence_length)

        self.assertTrue(mask[:2, sequence_length // 2 :].sum() == 0)

    def test_compute_perplexity(self):
        probs = np.arange(100).reshape(2, 5, 10) / 100

        ppl = FlaxWav2Vec2GumbelVectorQuantizer._compute_perplexity(probs)
        self.assertTrue(abs(ppl.item() - 141.4291) < 1e-3)

        # mask half of the input
        mask = np.ones((2,), dtype=np.bool)
        mask[0] = 0

        ppl = FlaxWav2Vec2GumbelVectorQuantizer._compute_perplexity(probs, mask)
        self.assertTrue(abs(ppl.item() - 58.6757) < 1e-3)

    def test_sample_negatives(self):
        batch_size = 2
        sequence_length = 10
        hidden_size = 4
        num_negatives = 3

        features = (np.arange(sequence_length * hidden_size) // hidden_size).reshape(
            sequence_length, hidden_size
        )  # each value in vector consits of same value
        features = np.broadcast_to(features[None, :], (batch_size, sequence_length, hidden_size))

        negative_indices = _sample_negative_indices(features.shape, num_negatives)

        features = features.reshape(-1, hidden_size)  # BTC => (BxT)C
        # take negative vectors from sampled indices
        sampled_negatives = features[negative_indices.reshape(-1)]
        negatives = sampled_negatives.reshape(batch_size, sequence_length, num_negatives, hidden_size).transpose(
            2, 0, 1, 3
        )

        self.assertTrue(negatives.shape == (num_negatives, batch_size, sequence_length, hidden_size))

        # make sure no negatively sampled vector is actually a positive one
        for negative in negatives:
            self.assertTrue(((negative - features.reshape(negative.shape)) == 0).sum() == 0.0)

        # make sure that full vectors are sampled and not values of vectors
        # => this means that `unique()` yields a single value for `hidden_size` dim
        self.assertEqual(np.unique(negatives, axis=-1).shape, (num_negatives, batch_size, sequence_length, 1))

    def test_sample_negatives_with_attn_mask(self):
        batch_size = 2
        sequence_length = 10
        hidden_size = 4
        num_negatives = 3

        features = (np.arange(sequence_length * hidden_size) // hidden_size).reshape(
            sequence_length, hidden_size
        )  # each value in vector consits of same value

        # second half of last input tensor is padded
        attention_mask = np.ones((batch_size, sequence_length), dtype=np.int8)
        attention_mask[-1, sequence_length // 2 :] = 0

        forbidden_indices = (
            np.arange(sequence_length // 2, sequence_length, dtype=np.int32) + (batch_size - 1) * sequence_length
        ).tolist()

        features = np.broadcast_to(features[None, :], (batch_size, sequence_length, hidden_size))

        negative_indices = _sample_negative_indices(features.shape, num_negatives, attention_mask=attention_mask)

        # make sure that no padding tokens are sampled
        self.assertTrue(all([idx not in negative_indices for idx in forbidden_indices]))

        features = features.reshape(-1, hidden_size)  # BTC => (BxT)C
        # take negative vectors from sampled indices
        sampled_negatives = features[negative_indices.reshape(-1)]
        negatives = sampled_negatives.reshape(batch_size, sequence_length, num_negatives, hidden_size).transpose(
            2, 0, 1, 3
        )

        self.assertTrue(negatives.shape == (num_negatives, batch_size, sequence_length, hidden_size))

        # make sure no negatively sampled vector is actually a positive one
        for negative in negatives:
            self.assertTrue(((negative - features.reshape(negative.shape)) == 0).sum() == 0.0)

        # make sure that full vectors are sampled and not just slices of vectors
        # => this means that `unique()` yields a single value for `hidden_size` dim
        self.assertEqual(np.unique(negatives, axis=-1).shape, (num_negatives, batch_size, sequence_length, 1))


@require_flax
@require_soundfile
@slow
class FlaxWav2Vec2ModelIntegrationTest(unittest.TestCase):
    def _load_datasamples(self, num_samples):
        ds = load_dataset("hf-internal-testing/librispeech_asr_dummy", "clean", split="validation")
        # automatic decoding with librispeech
        speech_samples = ds.sort("id").filter(
            lambda x: x["id"] in [f"1272-141231-000{i}" for i in range(num_samples)]
        )[:num_samples]["audio"]

        return [x["array"] for x in speech_samples]

    def test_inference_ctc_robust_batched(self):
        model = FlaxWav2Vec2ForCTC.from_pretrained("facebook/wav2vec2-large-960h-lv60-self", from_pt=True)
        processor = Wav2Vec2Processor.from_pretrained("facebook/wav2vec2-large-960h-lv60-self", do_lower_case=True)

        input_speech = self._load_datasamples(4)

        inputs = processor(input_speech, return_tensors="np", padding=True)

        input_values = inputs.input_values
        attention_mask = inputs.attention_mask

        logits = model(input_values, attention_mask=attention_mask).logits

        predicted_ids = jnp.argmax(logits, axis=-1)
        predicted_trans = processor.batch_decode(predicted_ids)

        EXPECTED_TRANSCRIPTIONS = [
            "a man said to the universe sir i exist",
            "sweat covered brion's body trickling into the tight loin cloth that was the only garment he wore",
            "the cut on his chest still dripping blood the ache of his overstrained eyes even the soaring arena around"
            " him with the thousands of spectators were trivialities not worth thinking about",
            "his instant panic was followed by a small sharp blow high on his chest",
        ]
        self.assertListEqual(predicted_trans, EXPECTED_TRANSCRIPTIONS)

    def test_inference_pretrained(self):
        model = FlaxWav2Vec2ForPreTraining.from_pretrained("facebook/wav2vec2-large-lv60", from_pt=True)
        feature_extractor = Wav2Vec2FeatureExtractor.from_pretrained(
            "facebook/wav2vec2-large-lv60", return_attention_mask=True
        )
        input_speech = self._load_datasamples(2)

        inputs_dict = feature_extractor(input_speech, return_tensors="np", padding=True)

        features_shape = (
            inputs_dict["input_values"].shape[0],
            model._get_feat_extract_output_lengths(np.array(inputs_dict["input_values"].shape[1])),
        )

        mask_time_indices = _compute_mask_indices(
            features_shape,
            model.config.mask_time_prob,
            model.config.mask_time_length,
            min_masks=2,
        )

        outputs = model(
            inputs_dict.input_values,
            attention_mask=inputs_dict.attention_mask,
            mask_time_indices=mask_time_indices,
        )

        # compute cosine similarity
        cosine_sim = optax.cosine_similarity(
            outputs.projected_states, outputs.projected_quantized_states, epsilon=1e-8
        )

        # retrieve cosine sim of masked features
        cosine_sim_masked = cosine_sim[mask_time_indices]

        # ... now compare to randomly initialized model

        config = Wav2Vec2Config.from_pretrained("facebook/wav2vec2-large-lv60")
        model_rand = FlaxWav2Vec2ForPreTraining(config)

        outputs_rand = model_rand(
            inputs_dict.input_values,
            attention_mask=inputs_dict.attention_mask,
            mask_time_indices=mask_time_indices,
        )

        # compute cosine similarity
        cosine_sim_rand = optax.cosine_similarity(
            outputs_rand.projected_states, outputs_rand.projected_quantized_states
        )

        # retrieve cosine sim of masked features
        cosine_sim_masked_rand = cosine_sim_rand[mask_time_indices]

        # a pretrained wav2vec2 model has learned to predict the quantized latent states
        # => the cosine similarity between quantized states and predicted states > 0.5
        # a random wav2vec2 model has not learned to predict the quantized latent states
        # => the cosine similarity between quantized states and predicted states is very likely < 0.1
        self.assertTrue(cosine_sim_masked.mean().item() - 5 * cosine_sim_masked_rand.mean().item() > 0)

    @require_pyctcdecode
    @require_librosa
    def test_wav2vec2_with_lm(self):
        ds = load_dataset("common_voice", "es", split="test", streaming=True)
        sample = next(iter(ds))

        resampled_audio = librosa.resample(sample["audio"]["array"], 48_000, 16_000)

        model = FlaxWav2Vec2ForCTC.from_pretrained("patrickvonplaten/wav2vec2-large-xlsr-53-spanish-with-lm")
        processor = Wav2Vec2ProcessorWithLM.from_pretrained("patrickvonplaten/wav2vec2-large-xlsr-53-spanish-with-lm")

        input_values = processor(resampled_audio, return_tensors="np").input_values

        logits = model(input_values).logits

        transcription = processor.batch_decode(np.array(logits)).text

        self.assertEqual(transcription[0], "bien y qué regalo vas a abrir primero")

    @require_pyctcdecode
    @require_librosa
    def test_wav2vec2_with_lm_pool(self):
        ds = load_dataset("common_voice", "es", split="test", streaming=True)
        sample = next(iter(ds))

        resampled_audio = librosa.resample(sample["audio"]["array"], 48_000, 16_000)

        model = FlaxWav2Vec2ForCTC.from_pretrained("patrickvonplaten/wav2vec2-large-xlsr-53-spanish-with-lm")
        processor = Wav2Vec2ProcessorWithLM.from_pretrained("patrickvonplaten/wav2vec2-large-xlsr-53-spanish-with-lm")

        input_values = processor(resampled_audio, return_tensors="np").input_values

        logits = model(input_values).logits

        # test user-managed pool
        with multiprocessing.get_context("fork").Pool(2) as pool:
            transcription = processor.batch_decode(logits.numpy(), pool).text

        self.assertEqual(transcription[0], "bien y qué regalo vas a abrir primero")

        # user-managed pool + num_processes should trigger a warning
        with CaptureLogger(processing_wav2vec2_with_lm.logger) as cl, multiprocessing.get_context("fork").Pool(
            2
        ) as pool:
            transcription = processor.batch_decode(logits.numpy(), pool, num_processes=2).text

        self.assertIn("num_process", cl.out)
        self.assertIn("it will be ignored", cl.out)

        self.assertEqual(transcription[0], "bien y qué regalo vas a abrir primero")

    @require_pyctcdecode
    @require_librosa
    def test_wav2vec2_with_lm_invalid_pool(self):
        ds = load_dataset("common_voice", "es", split="test", streaming=True)
        sample = next(iter(ds))

        resampled_audio = librosa.resample(sample["audio"]["array"], 48_000, 16_000)

        model = FlaxWav2Vec2ForCTC.from_pretrained("patrickvonplaten/wav2vec2-large-xlsr-53-spanish-with-lm")
        processor = Wav2Vec2ProcessorWithLM.from_pretrained("patrickvonplaten/wav2vec2-large-xlsr-53-spanish-with-lm")

        input_values = processor(resampled_audio, return_tensors="np").input_values

        logits = model(input_values).logits

        # change default start method, which should trigger a warning if different than fork
        multiprocessing.set_start_method("spawn")
        with CaptureLogger(processing_wav2vec2_with_lm.logger) as cl:
            transcription = processor.batch_decode(logits.numpy()).text

        self.assertIn("Falling back to sequential decoding.", cl.out)
        self.assertEqual(transcription[0], "bien y qué regalo vas a abrir primero")
